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Quantitative detections of proteins for single cells have made great contributions to tumor heterogeneity and immune variance while effective tools of measuring single-cell intracellular proteins are under developments. This study reported a flow cytometer based on constriction microchannel and light modulation, which was capable of quantifying intracellular proteins for single cells with high resolution. Cells tagged with fluorescein labelled antibodies were squeezed into the constriction microchannel as either the calibration or detection structure where a light source with a carrier wave was used for fluorescent modulation, which was further demodulated into the low-frequency domain and translated into numbers of single-cell proteins. In platform characterization, the inclusion of light modulation was shown to effectively improve the detection resolution from ~1000 intracellular proteins per cell without modulation to ~100 intracellular proteins per cells with modulation. As demonstrations, expressions of mutant p53 or phosphorylated p53 from tens of thousands of single T47D and/or A431 cells were quantitatively measured by the microfluidic quantitative flow cytometer, which were 1.78 ± $0.96 \times10$ 5 mutant p53 per cell for T47D cells (${N}_{c} =10\,315$), 1.99 ± $1.49\times10$ 5 mutant p53 per cell for A431 cells (${N}_{c} =15\,665$), and 6.34 ± $7.50\times10$ 3 phosphorylated p53 per cell for A431 cells treated with doxorubicin (${N}_{c} =12\,812$). In conclusion, the inclusion of light modulation can effectively decrease electrical and optical noises and therefore improve detection resolution in microfluidic quantitative flow cytometry. [ABSTRACT FROM AUTHOR]

We synthesized Mn-doped core/shell quantum dots (QDs) with the structure of Mn:ZnS/ZnxCd $_{(1-x)}\text{S}$ /ZnS to sensitize silicon-based CCDs for ultraviolet (UV) image detection. Taking the advantage of QD’s long fluorescence lifetime in the timescale of microsecond, a single-channel time-separated UV/visible (VIS) dual-band panoramic detector was designed. The evolutions of the microscopic properties (i.e., particle diameter and lattice constant) and the fluorescence properties (i.e., absorption, photoluminescence (PL), quantum yield, and lifetime) of the QDs with the shell growth were studied. A SiO2 layer is encapsulated on the surface to mix with SiO2 Sol to form a QDs@SiO2 film, which further improves the stability of QDs. Meanwhile, the SiO2 layer has limited absorption to deep UV light, effectively expanding the detector’s applicable band onto UV-C (200–280 nm). The device prepared by this is stable in performance, and the external quantum efficiency (EQE) in the UV-C band can reach as high as 18.26% in such devices with similar structures. Overall, this study could provide new insights into the panoramic detector with high features of UV-C sensitivity and stability. [ABSTRACT FROM AUTHOR]

The two underlying requirements of face age progression, i.e., aging accuracy and identity permanence, are not well studied in the literature. This paper presents a novel generative adversarial network based approach to address the issues in a coupled manner. It separately models the constraints for the intrinsic subject-specific characteristics and the age-specific facial changes with respect to the elapsed time, ensuring that the generated faces present desired aging effects while keeping personalized properties stable. To render photo-realistic facial details, high-level age-specific features conveyed by the synthesized face are estimated by a pyramidal adversarial discriminator at multiple scales, which simulates the aging effects in a finer way. Further, an adversarial learning scheme is introduced to simultaneously train a single generator and multiple parallel discriminators, resulting in smooth continuous face aging sequences. The proposed method is applicable even in the presence of variations in pose, expression, makeup, etc., achieving remarkably vivid aging effects. Quantitative evaluations by a COTS face recognition system demonstrate that the target age distributions are accurately recovered, and 99.88 and 99.98 percent age progressed faces can be correctly verified at 0.001 percent FAR after age transformations of approximately 28 and 23 years elapsed time on the MORPH and CACD databases, respectively. Both visual and quantitative assessments show that the approach advances the state-of-the-art. [ABSTRACT FROM AUTHOR]

Illumination normalization for face recognition is very important when a face is captured under harsh lighting conditions. Instead of designing hand-crafted features, in this paper we formulate face illumination normalization as an image-to-image translation task. A great challenge of face normalization is that human facial structures are particularly sensitive to image structure distortion, which frequently occurs in traditional image-to-image translation tasks. Unfortunately, sometimes even slight facial structure distortions may prohibit human eyes and machine face recognition methods from identifying face identities. To address this issue, a novel GAN-based network architecture called the asymmetric joint generative adversarial network (AJGAN) is developed to normalize face images under arbitrary illumination conditions, without known face geometry and albedo information. In addition, an illumination normalization GAN $G_1$ and an asymmetric relighting GAN $G_2$ that maps a frontal-illuminated image to images with various lighting conditions are incorporated in AJGAN to maintain personalized facial structures. To avoid image blurring caused by the under-constrained relighting mapping, we introduce a scheme of one-hot lighting labels into $G_2$ and enforce label classification loss. Furthermore, the number of training images starting from a very limited number of labels is dynamically extended by the combination of different lighting labels. Qualitative and quantitative experiments on three databases validate that AJGAN significantly outperforms the state-of-the-art methods. [ABSTRACT FROM AUTHOR]

Electromagnetic flowmeter (EMF) is a widely used flow measurement instrument in the 20th century. It is based on the Faraday’s law and developed rapidly in recent decades. It plays an important role in our daily life such as water treatment, food production and chemical industry. An improved excitation structure with E-type frame made by permeable material added in the traditional Helmholtz coil is proposed in this paper to simulate the distribution of the magnetic field. The optimal coil width is obtained which can ensure the uniformity of magnetic field with minimum physical size. A compensate method is discussed to improve the switch speed of the magnetic field so that the EMF can be used to measure fast flow. [ABSTRACT FROM AUTHOR]

A cross-layer design methodology that jointly optimizes the link-layer network flow rate and the physical layer transmission power wherein rate is developed for energy-constrained underwater wireless sensor networks. The objective of the design is to maximize the lifetime of the network operation for a given network topology and a bound of the total transmission time of all links. Initially, each node is set to transmit at the most energy-efficient transmission rate, which is derived using an underwater acoustic channel model. A constrained least square problem then is formulated which yields an analytical solution of the optimal network flow at each link that maximizes the network lifetime. If the timing constraint is not met, a new iteration will begin with the restriction on per-node energy consumption incrementally relaxed. Usually, the algorithm converges within a couple of iterations. Two design examples, a linear configured network, and a rhombus configured network are used to demonstrate the design procedures. Extensive simulations have been performed and superior performance (longer network lifetime) of this proposed design has been observed. [ABSTRACT FROM AUTHOR]