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Fiber optic temperature sensors for small-scale heat sources have an urgent need in many industrial fields, for example, the temperature field of the laser heat source, mini LED, microchip, and so on. To the best our knowledge, we first propose and demonstrate an ultrashort fiber optic temperature sensor based on a Fabry–Perot (FP) interferometer which combines a low reflection fiber Bragg grating (FBG) with Fresnel reflection (i.e., ~4%) on the fiber end face. This unique FBG exhibits a broad Gaussian spectrum with a full-width at half-maximum (FWHM) bandwidth of 12.4 nm. This FBG-FP cavity structure was fabricated by a femtosecond laser line-by-line (LbL) scanning technology, and it has stronger mechanical strength due to no damage to the fiber material compared to other fiber optic FP interferometers. The free spectrum range (FSR) of the FBG-FP cavity is about 1.56 nm, corresponding to the cavity length can be calculated to be about $530 \mu \text{m}$ . The selected dip wavelength of the FBG-FP cavity sensor changes linearly with the temperature increase, corresponding to the temperature sensitivity of 10.8 pm/°C. Moreover, the FBG-FP cavity sensor exhibits a high spatial resolution of $580 \mu \text{m}$ and it can be used to measure the temperature of the small-scale laser spot due to its compact structure. The experimental results show the temperatures at different positions of 1064 nm laser exposure area are 138.4 °C, 111.5 °C, and 74.4 °C, respectively.

The amorphous oxide semiconductor (AOS) thin-film transistors (TFTs) are of great interest due to their high mobility, excellent homogeneity, and low processing temperature. With energy conservation and flexible electronics emerging, further reducing post-processing temperatures has become a primary concern. $\text{O}_{{2}}$ plasma treatment has received much attention because it can supply oxygen atoms directly and enhance the performance of AOS thin films at low temperatures. In this study, we provide a combined post-treatment incorporating low-temperature annealing and $\text{O}_{{2}}$ plasma treatment to improve the performance of praseodymium-doped indium zinc oxide (PrIZO) thin films and TFTs. With the increase of $\text{O}_{{2}}$ plasma treatment power, the density of PrIZO thin films first increases and then decreases, reaching a maximum of 6.3 $\text{g}\cdot $ cm $^{-{3}}$ at 40 W. With the increasing $\text{O}_{{2}}$ plasma treatment power, the surface roughness of PrIZO thin films first decreases and then increases, achieving a minimum of 0.49 nm at 40 W. The optimized PrIZO TFT exhibits good electric performance with a $\mu _{\text {sat}}$ of 17.9 cm $^{{2}} \cdot \text{V}^{-{1}} \cdot \text{s}^{-{1}}$ , a subthreshold swing (SS) of 0.40 $\text{V}\cdot $ dec $^{-1}$ , a threshold voltage ( ${V}_{\text {TH}}$ ) of −1.1 V, and an ${I}_{ \mathrm{\scriptscriptstyle ON}}/{I}_{ \mathrm{\scriptscriptstyle OFF}}$ ratio of 7.4 $\times \,\,10^{{7}}$ ultimately. A novel combined posttreatment incorporating low-temperature annealing and $\text{O}_{\mathbf {2}}$ plasma treatment is proposed and proved promising.

A printable, flexible display panel is an important trend in the field of information display, which requires better mechanical and electrical properties of device materials. Polymer–metal oxide composite materials are promising in the functional layer of a thin-film transistor (TFT) and can be sufficiently fabricated by polymer–metal salt solution systems through the sol–gel process. For the development of polymer–metal oxide composite ink, it is necessary to study the film-forming mechanism of the composite film during solidification, which is an important reference in ink component design. However, the evolution of the composite structure is quite complex, which brings a challenge to characterization and analyzation. We applied a series of characterization methods to study the film-forming process of composite ink from sol to gel and to solid, and an emerging testing technology, nano-infrared spectroscopy (nano-IR), was applied to characterize the gel film. The research conclusion showed that the type of functional group can significantly affect the morphology of the initial particle and can finally determine the microstructure of the composite film. The study provides references for the development of composite ink as well as the characterization method for ink and film with complex composition.

• The structure and properties of different kinds of 2D Xenes are presented. • The synthesis methods of 2D Xenes are summarized, including bottom-up and top-down approaches. • The photoelectronic properties of 2D Xenes is described, and some devices based on 2D Xenes are listed. • It provides an outlook of direction, challenges, and opportunities for future research on devices based on 2D Xenes. Two-dimensional materials, especially graphene-like emerging single-element materials two-dimensional (2D) Xenes, have attracted great research interest since the advent of the graphene. In this review paper, 12 kinds of different Xenes were introduced according to the group and element quality, and their main synthesis methods are outlined. The advantages and limitations of the synthesis methods are analyzed in detail. By summarizing the current photoelectronic properties of 2D Xenes materials, it is found that Xenes in the same group have similar properties, such as the buckling properties of the fourth group and the anisotropy of the fifth group. In addition, the performance of photoelectronic applications based on 2D Xenes materials are summarized, and some possible methods are proposed to improve the performance of future 2D Xenes material photoelectronic devices. [ABSTRACT FROM AUTHOR]

We present a low-cost clinically viable ventilator design, AmbuBox, using a controllable pneumatic enclosure and standard manual resuscitators that are readily available (AmbuBag), which can be rapidly deployed during pandemic and mass-casualty events with a minimal set of components to manufacture and assemble. The AmbuBox is designed to address the existing challenges presented in the existing low-cost ventilator designs by offering an easy-to-install and simple-to-operate apparatus while maintaining a long lifespan with high-precision flow control. As an outcome, a mass-producible prototype of the AmbuBox has been devised, characterized, and validated in a bench test setup using a lung simulator. This prototype will be further investigated through clinical testing. Given the potentially urgent need for inexpensive and rapidly deployable ventilators globally, the overall design, operational principle, and device characterization of the AmbuBox system have been described in detail with open access online. Moreover, the fabrication and assembly methods have been incorporated to enable short-term producibility by a generic local manufacturing facility. In addition, a full list of all components used in the AmbuBox has been included to reflect its low-cost nature.

We present a low-cost clinically viable ventilator design, AmbuBox, using a controllable pneumatic enclosure and standard manual resuscitators that are readily available (AmbuBag), which can be rapidly deployed during pandemic and mass-casualty events with a minimal set of components to manufacture and assemble. The AmbuBox is designed to address the existing challenges presented in the existing low-cost ventilator designs by offering an easy-to-install and simple-to-operate apparatus while maintaining a long lifespan with high-precision flow control. As an outcome, a mass-producible prototype of the AmbuBox has been devised, characterized, and validated in a bench test setup using a lung simulator. This prototype will be further investigated through clinical testing. Given the potentially urgent need for inexpensive and rapidly deployable ventilators globally, the overall design, operational principle, and device characterization of the AmbuBox system have been described in detail with open access online. Moreover, the fabrication and assembly methods have been incorporated to enable short-term producibility by a generic local manufacturing facility. In addition, a full list of all components used in the AmbuBox has been included to reflect its low-cost nature.

The propagation of a truncated Airy beam with spatial phase modulation (SPM) is investigated in Kerr nonlinearity with an optical lattice. Before the truncated Airy beam enters the optical lattice, a sinusoidal phase is introduced on the wave-front of the beam. The effect of the spatial phase modulation and optical lattice on propagation behavior is analyzed by direct numerical simulation. It is found that the propagation direction of a truncated Airy beam can be effectively controlled by adjusting the values of phase shift. The effects of optical amplitude, truncation factor, spatial modulation frequency, lattice period and lattice depth on the propagation are discussed in detail. By choosing a high modulation depth, the finite-energy Airy beam can be deflected with a large deflection angle in an optical lattice.

The digital twins concept enhances modeling and simulation through the integration of real-time data and feedback. This review elucidates the foundational elements of digital twins, covering their concept, entities, domains, and key technologies. More specifically, we investigate the transformative potential of digital twins for the wastewater treatment engineering sector. Our discussion highlights the application of digital twins to wastewater treatment plants (WWTPs) and sewage networks, hardware (i.e., facilities and pipes, sensors for water quality and activated sludge, hydrodynamics, and power consumption), and software (i.e., knowledge-based and data-driven models, mechanistic models, hybrid twins, control methods, and the Internet of Things). Furthermore, two cases are provided, followed by an assessment of current challenges in and perspectives on the application of digital twins in WWTPs. This review serves as an essential primer for wastewater engineers navigating the digital paradigm shift.

Encapsulation of few cells into monodisperse picolitre droplets is an extremely critical step in the process of the droplet based single cell analysis. This paper presents a novel approach, not based on micro-fluidic chips fabricated by standard soft lithography technique, for encapsulating cells into droplets actuated by microfluidic pulse inertia force. The principle of the encapsulating process is to actuate a hollow PZT stack by a signal generator and a voltage amplification to provide an enough pulse inertia force for a tapered glass capillary and the cell suspension inside to eject droplets in mineral oil and a certain number of the cells will be randomly encapsulated in monodisperse picolitre droplets. The tapered glass capillary was fabricated by a glass heating process without complicated microfabrication technology. Therefore, it has the advantages of good chemical resistance, low friction, easy to manufacture and low cost. The minimum size of the spherical cell droplets that can be reached is 20 μm in diameter and about 4 picolitres in volume. The percentage of the droplets with single HL60 cell can reach 42% when the droplet size is 40 μm and the concentration of the cell suspension is 1 × 108cells per milliliter since the alternate changed pulse inertia force can make the cells well dispersed in the tapered capillary. The percentage of viable cells that can be reached is 82% as determined by trypan blue staining, when the cell droplet size is 120 μm. The experiment results present a novel strategy for droplet-based single cell analysis.

Tb0.29(Dy1-xPrx)0.71Fe1.97(x=0, 0.1, 0.2 and 0.3) alloys prepared by the directional solidification method were treated at 1073, 1123, 1173, 1223 and 1273 K for 4 h for homogenization, respectively. The magnetostriction, micro-morphology and composition distribution were studied by the standard resistance strain gauge technique, optical microscopy and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS). The results indicated that heat treatment could make the microstructure of alloys homogeneous effectively and improve the magnetostriction significantly. The optimum temperature was 1223 K. Compared to the as-cast ones, the increase amplitudes of magnetostriction of the corresponding samples were 39.5%, 64.9%, 95.3% and 50.8% when x=0, 0.1, 0.2 and 0.3, respectively at the compressive stress of 2 MPa and a magnetic field of 80 kA/m. The compressive stress could also improve the magnetostriction. However, further Pr element addition and over high heat treatment temperature would lead to the excessive decomposition of PrFe2and destroy the homogeneity, resulting in the decline of magnetostriction of alloys.

We present an optical steering method in optical lattice with Kerr nonlinearity based on spatial phase modulation. By choosing proper phase modulation parameters, we can easily realize optical deflection, optical switching, and splitting of optical beams. The effect of lattice depth and lattice period on the optical steering is also discussed in detail.

An athermal design for the KTP electro-optical modulator is presented. By using the wave coupling theory of linear electro-optic effect and taking account of thermal expansion, the more accurate athermal static phase retardation (ASPR) directions in potassium titanyl phosphate (KTP) are found, and the optimized design for a transverse amplitude modulator at ASPR orientation is obtained. The numerical results show that the modulator with an athermal Soleil-Babinet compensator is of excellent thermal stability, and the acceptable error of the ASPR direction is less than 0.1°.

Abstract: This paper introduces strategies to detect software bugs in earlier life cycle stage in order to improve test efficiency. Static analysis tool is one of the effective methods to reveal software bugs during software development. Three popular static analysis tools are introduced, two of which, PolySpace and Splint, are compared with each other by analyzing a set of test cases generatedd by the authors. PolySpace can reveal 60% bugs with 100%R/W ratio (ratio of real bugs and total warnings), while Splint reveal 73.3% bugs with 44%R/W ratio. And they are good at finding different categories of bugs. Two strategies are concluded to improve test efficiency, under the guideline that static analysis tools should be used in finding different categories of bugs according to their features. The first one aims at finding bugs as many as possible, while the second concentrates to reduce the average time on bug revelation. Experimental data shows the first strategy can find 100% bugs with 60%R/W ratio, the second one find 80% bugs with 66.7%R/W ratio. Experiment results prove that these two strategies can improve the test efficiency in both fault coverage and testing time. [Copyright &y& Elsevier]

Abstract: This paper proposes a new framework for video editing in gradient domain. The spatio-temporal gradient fields of target videos are modified and/or mixed to generate a new gradient field which is usually not integrable. We compare two methods to solve this “mixed gradient problem”, i.e., the variational method and loopy belief propagation. We propose a 3D video integration algorithm, which uses the variational method to find the potential function whose gradient field is closest to the mixed gradient field in the sense of least squares. The video is reconstructed by solving a 3D Poisson equation. The main contributions of our framework lie in three aspects: first, we derive a straightforward extension of current 2D gradient technique to 3D space, thus resulting in a novel video editing framework, which is very different from all current video editing software; secondly, we propose using a fast and accurate 3D discrete Poisson solver which uses diagonal multigrids to solve the 3D Poisson equation, which is up to twice as fast as a simple conventional multigrid algorithm; finally, we introduce a set of new applications, such as face replacement and painting, high dynamic range video compression and graphcut based video compositing. A set of gradient operators is also provided to the user for editing purposes. We evaluate our algorithm using a variety of examples for image/video or video/video pairs. The resulting video can be seamlessly reconstructed. [Copyright &y& Elsevier]

The effect of the polarization state on electro-optic coupling is studied by using the wave coupling theory of the linear electro-optic effect. The numerical results show that the polarization state obviously influences the electro-optic coupling. The conditions for realizing perfect coupling are emphasized. As an application of perfect coupling, a novel polarization rotator, which can rotate the polarization of a light beam with an arbitrary angle but keep the output intensity unchanged, is presented.

This paper presents a method to make vanadium dioxide (VO2) crystallites on silicon substrates by reactive ion beam sputtering. The thickness of the thin film is about 100nm. The phase transition temperature of VO2is 65°C. The transmittance of the semiconducting phase VO2is about 50% and it is reduced to as low as 3% in metal phase at the infrared wavelenghth spectrum. The extinction ratio of the optical switches is 12dB. and the insertion loss is of 1-2dB. The switching time is about 1ms.

A new triterpenoid saponin, named segetoside C (1), and two known saponins, vaccaroid A (vaccaroside A) (2) and dianoside G (3), have been isolated from the seeds of Vaccaria segetalis. On the basis of chemical reaction and spectral data, the structure of segetoside C (1) has been established as: gypsogenic acid-28-O-[β-D-glucopyranosyl-(1 → 3)]-[6-O-acetyl-β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranosyl-(1 → 6)]-β-D-glucopyranoside.

The modulation instability of quasi-plane-wave optical beams is investigated in the frame of generalized Schrodinger equation with the nonlinear term of a general form. General expressions are derived for the dispersion relation, the critical transverse spatial frequency, as well as the instability growth rate. The analysis generalizes the known results reported previously. A detailed discussion on the modulation instability in biased centrosymmetric photorefractive media is also given.

A new phenylpropanoid glycoside, segetoside A, has been isolated from the seeds of Vaccaria segetalis, and shown to be α-d-(6-O-dihydroferuloyl)glucopyranosyl(1 → 2)-β-d- fructofuranoside.

The low radical surgery rate of pancreatic cancer leads to increased local recurrence and poor prognosis. Gemcitabine (GEM) is the preferred chemotherapeutic for pancreatic cancer. However, systemic chemotherapy with GEM has reached a bottleneck due to its serious side effects after frequent injections. In this study, GEM is successfully enwrapped into electrospun fibers via microsol electrospinning technology to form a stable core–shell fibrous structure. The GEM release rate can be adjusted by altering the thickness of the hyaluronan‐sol inner fiber and the quantity of loaded GEM, and the release can be sustained for as long as three weeks. In vitro assays show that these electrospun fibers effectively inhibit pancreatic cancer cells and promote apoptosis. In vivo studies show that the fibrous membranes are better for inhibiting the growth of residual tumors than that of integrated tumors. Furthermore, immunohistochemistry results show that GEM‐loaded fibers promote a higher cell apoptosis rate than does systemically injected GEM in residual tumors. In addition, the local delivery of GEM with fibers significantly reduces liver toxicity. In summary, a core–shell electrospun fiber for the controlled and localized delivery of GEM, which greatly improves the treatment of residual tumors and prevents pancreatic tumor recurrence, is developed. A typical water‐soluble drug, gemcitabine, is successfully enwrapped into electrospun fibers via micro‐sol electrospinning technology to prevent pancreatic cancer recurrence.