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Few studies on the factors associated with multiloculated breast abscesses during lactation have been performed. We collected data on 1805 patients with breast abscesses during lactation, who were divided into single-cavity breast abscess (N = 1298) and multiloculated breast abscess groups (N = 507). Fifteen variables were compared between the groups. The results showed significant differences between the two groups in (1) whether in the puerperium, (2) separated from the baby > 12 h in the last week, (3) exclusively breastfeeding or not in the last 2 weeks, (4) inverted nipple on the affected side or not, (5) history of fever or not, (6) breast skin redness and swelling on the affected side or not, (7) nipple pain or not in the last 2 weeks, and (8) whether the breasts had been massaged by non-medical staff in the last month, with (1), (5), (6), and (8) being independent risk factors. Patients in the puerperium, separated from the baby, not exclusively breastfeeding, having an inverted nipple on the affected side, accompanied by fever, with breast skin redness and swelling on the affected side, nipple pain, and having undergone a breast massage by non-medical staff are more likely to develop multiloculated breast abscesses.

An ultrasensitive label-free electrochemical sensor based on a homemade imprinted polypyrrole (PPy) polymer film was prepared to achieve quantitative determination of Lactobacillus rhamnosus GG (LGG). The LGG-imprinted polymer (LIP) film was deposited on a portable screen-printed electrode (SPE) via electropolymerization, which constituted an independent integrated system. The main preparation parameters of the LIP sensor were investigated to obtain optimal performance. Under optimized conditions, the peak current response of the LIP sensor showed a linear relationship with the logarithmic value of LGG concentration in the range from 10

Manipulating the polarization state of light is essential for on-chip photonics and quantum information processing. We demonstrate the generation of different polarization states via a single metasurface based on geometrical-scaling-induced phase modulations.

Photonic quantum information processing relies on operating the quantum state of photons, which usually involves bulky optical components unfavorable for system miniaturization and integration. Here, we report on the transformation and distribution of polarization-entangled photon pairs with multichannel dielectric metasurfaces. The entangled photon pairs interact with metasurface building blocks, where the geometrical-scaling-induced phase gradients are imposed, and are transformed into two-photon entangled states with the desired polarization. Two metasurfaces, each simultaneously distributing polarization-entangled photons to spatially separated multiple channels M (N), may accomplish M×N channels of entanglement distribution and transformation. Experimentally we demonstrate 2×2 and 4×4 distributed entanglement states, including Bell states and superposition of Bell states, with high fidelity and strong polarization correlation. We expect this approach paves the way for future integration of quantum information networks.

Various multi-drug-resistant microorganisms have appeared while a single antibacterial agent is increasingly no longer adequate for dealing with these resistant microorganisms. Herein, commercially purchased 50 nm-average-diameter silver nanoparticles (AgNPs) and Lactobacillus buchneri-isolated surface-layer proteins (SLPs) as a capping agent were used to fabricate a hybrid antibacterial agent (SLP-AgNPs) with enhanced antibacterial activity, and the possible synergistic antibacterial mechanism was explored. Characterization results revealed that SLP-AgNPs were uniformly surrounded by protein corona provided from SLP, and the formulations were mainly mediated by the electrostatic interactions and hydrogen bonding, which was evidenced by the results of Fourier transform infrared spectroscopy. According to the antibacterial tests, the minimum inhibitory concentration of SLP-AgNPs against Salmonella enterica (0.010 mg/mL) and Staphylococcus aureus (0.005 mg/mL) was 5-10 times lower than that of bare AgNPs, and while SLP-AgNPs showed a higher antibiofilm activity. Furthermore, bacterial cells exposed to SLP-AgNPs exhibited higher cell membrane permeability and stronger inhibition of respiratory-chain dehydrogenase activity, resulting in more severe cell death compared with bare AgNPs. The synergistic effect of SLP on AgNPs was probably carried out by enhanced function of adhesion to bacteria and antibacterial ability of SLP and SLP's supramolecular lattice structure on the sustained release of silver ion.

In this paper, based on the inverse of block companion matrix pencils associated with matrix polynomials, a first-order state-space realization in descriptor system form for a general high-order linear system is derived. An important feature of the proposed realization is that it allows the high-order linear system to be singular. While in the case that the high-order system is nonsingular, two realizations in normal state-space system forms are directly deduced. With the help of the proposed realization, a generalized Popov Belevitch Hautus (PBH) criterion for high-order systems is then established in terms of the original system matrix polynomials. Examples are studied which well demonstrate the proposed theories.

Rough surfaces lead to diffused light in both reflection and transmission, thereby blurring the reflected and transmitted images. Here, we merge the traditionally incompatible diffuse reflection and undistorted transmission by introducing the concept of random-flip metasurfaces made of randomly flipped components. These metasurfaces have a globally random phase in reflection that leads to diffuse reflection, while the local space inversion and reciprocity principle ensure distortion-free transmission. Notably, the metasurface reflects like a rough surface yet transmits like a smooth one in a broad spectrum. On the basis of complementary random arrays of gold nanorods, we verified this functionality by both optical spectroscopy and imaging experiments over a broad range of frequencies from the visible to the infrared regime. This feature, which originates from breaking the phase correlation between reflection and transmission by the metasurface, could enable a range of new optical materials and display technology.

Manipulation of polarization states with metasurfaces is a compelling approach for on-chip photonics and portable information processing. Yet it remains challenging to generate different types of polarization states with a single piece of a metasurface. This paper demonstrates a metasurface to resolve this issue, which is made of L-shaped resonators with different geometrical sizes. Each resonator diffracts a right- or left-handed circularly polarized state with an additional geometrical-scaling-induced phase. The type of polarization state of each diffracted beam is determined by the enantiomorphism, size, and spatial sequence of the resonators in the unit cell. The number of the beams is modulated by the geometry and separation of the resonators. We provide examples to illustrate how to achieve the specific number of diffracted beams with the desired polarization states in experiments. We suggest that this strategy can be applied for integrated photonics and portable quantum information processing.

By introducing geometrical-scaling-induced phase modulations, we demonstrate in this work that an assembly of circularly polarized and linearly polarized states can be simultaneously generated by a single metasurface made of L-shaped resonators with different geometrical features. Each resonator of the metasurface diffracts either a right-handed or left-handed circular polarized states, with an additional phase modulation determined by its geometry features. The interaction of the diffracted fields leads to the desired output beams, where the polarization state and the propagation direction can be accurately controlled. As an example of potential applications, we show that an image can be encoded with different polarization profiles at different diffraction orders and decoded with a polarization analyzer. This approach resolves a challenging problem in integrated optics and is inspiring for on-chip quantum information processing.

Traditional optical elements, such as waveplates and polarization beam splitters, are essential for quantum state tomography (QST). Yet, their bulky size and heavy weight are prejudicial for miniaturizing quantum information systems. Here, we introduce nondiffractive silicon metasurfaces with high transmission efficiency to replace the traditional optical elements for QST of polarization-entangled states. Two identical silicon metasurfaces are employed, and each metasurface comprises four independent districts on a micrometer scale. The unit cell of each district consists of two silicon nanopillars with different geometrical sizes and orientation angles, and the interference of the scattered waves from the nanopillars leads to a single output beam from the district with a specific polarization state with a transmission efficiency above 92%. When the two-photon polarization-entangled state shines on different districts of two metasurfaces, each photon of the photon pair interacts with the local nanopillars within the district, and the two-photon state is projected onto 16 polarization bases for state reconstruction. We experimentally demonstrate the reconstruction of four input Bell states with high fidelities. This approach significantly reduces the number of conventional optical components in the QST process and is inspiring for advancing quantum information technology.

Excessive application of phosphorus fertilizer leads to high soil available phosphorus content but low phosphorus use efficiency in the main production areas of spring rape in eastern Qinghai. Understanding the effects of phosphorous application rates on the growth, phosphorus absorption, soil phosphorus balance in the field of spring rape could improve nutrient management of spring rape, and benefit for the sustainable development of agriculture in Qinghai-Tibet Plateau. A field experiment was carried out in Huzhu County of Qinghai Province from 2017 to 2018. We mea-sured seed yield, phosphorus uptake and oil content of spring rape under five phosphorous fertilizer rates (0, 30, 60, 90 and 120 kg P青海省东部春油菜主产区的土壤速效磷含量高、磷肥施用量大、磷肥利用率低。研究不同施磷量对春油菜的生长、磷素吸收和利用、土壤磷素平衡的影响,可为该地区春油菜田养分高效管理提供科学依据,对保障青藏高原农业可持续发展具有重要意义。本研究于2017和2018年在青海省互助县开展了田间试验,设置0、30、60、90、120 kg P

Manipulating the polarization state of light is essential for integrated photonics and quantum information technology. By introducing geometrical-scaling-induced phase modulations, we report here the simultaneous generation of different types of polarization states with a single metasurface.

In this talk, we present our recent work on tuning the polarization states of light wave with 2D or 3D metastructures. First, we illustrate an approach to tune the phase difference of light via time retardation in a microstructured surface. Second, we demonstrate a general mechanism to construct the dispersion-free metastructure. Third, we present a freely tunable polarization rotator for broadband terahertz waves using a metastructure, and also an example on dynamically-switching the polarization state based on the phase transition of vanadium dioxide. The investigations provide some guidelines to control the polarization state of light at subwavelength scale.

Manipulating the polarization of light on the microscale or nanoscale is essential for integrated photonics and quantum optical devices. Nowadays, the metasurface allows one to build on-chip devices that efficiently manipulate the polarization states. However, it remains challenging to generate different types of polarization states simultaneously, which is required to encode information for quantum computing and quantum cryptography applications. By introducing geometrical-scaling-induced (GSI) phase modulations, we demonstrate that an assembly of circularly polarized (CP) and linearly polarized (LP) states can be simultaneously generated by a single metasurface made of L-shaped resonators with different geometrical features. Upon illumination, each resonator diffracts the CP state with a certain GSI phase. The interaction of these diffractions leads to the desired output beams, where the polarization state and the propagation direction can be accurately tuned by selecting the geometrical shape, size, and spatial sequence of each resonator in the unit cell. As an example of potential applications, we show that an image can be encoded with different polarization profiles at different diffraction orders and decoded with a polarization analyzer. This approach resolves a challenging problem in integrated optics and is inspiring for on-chip quantum information processing., 10pages, 6figures, to be published in Physical Review X

Background: Several Chinese mothers experience problems related to their breasts during breastfeeding and are referred to hospitals for treatment after a massage by a "cuirushi." Some of these patients develop large breast abscesses. Notably, the treatment of residual milk cavities is difficult after pus aspiration. Lactational residual milk cavities in the breast hinder effortless breastfeeding, but no solution has been reported thus far. This study aims to explore the use of a simple and minimally invasive method for treating lactational residual milk cavities and enabling mothers to breastfeed effortlessly. Materials and Methods: We retrospectively analyzed clinical data of 28 patients with lactational residual milk cavities treated using negative-pressure suction cannula and drainage at our department from December 2016 to May 2019. The success rate, safety, and feasibility of this technique are summarized. Results: Among the 28 patients, the first catheterization was successful in 7 (25%) patients, the second in 13 (46.4%) patients, and the third or subsequent catheterizations in 8 (28.6%) patients. The intubation time was 20 days in 13 patients. During and after treatment, 21 patients (75%) continued breastfeeding with the affected breast. Conclusions: Ultrasound-guided negative-pressure suction cannula is a new method to treat lactational residual milk cavities that may remain after initial therapy for lactational breast abscess. The treatment of lactational residual milk cavities offers significant advantages in supporting mothers during breastfeeding.

The quantum Toffoli gate can be utilized as a fundamental building block for translating more complicated classical operations into quantum algorithms, so its efficient construction is more conducive to the realization of quantum computation in large-scale than two-qubit universal quantum logic gates. Assisted by the spatial degree of freedom based on weak cross-Kerr nonlinearities, a construction scheme of the nearly deterministic Toffoli gate is presented. After the measurement on the coherent state, the required swap transformations and single-photon transformations are performed by the classical feed-forward to complete the construction task if nonzero phase shifts are displayed. The scheme proposed here is more efficient than those based on the standard model of linear optics and more feasible than those fulfilled by a variety of two-qubit universal quantum logic gates and one-qubit gates. Moreover, with mature measurement methods and simple optical elements and operations, this scheme enhances the feasibility of experiments to construct the Toffoli gate.

A quantum logic gate is an indispensable fundamental element for completing tasks of quantum information processing, such as quantum computation and scalable quantum networks. With the help of weak cross-Kerr nonlinearities, we propose an efficient optical one-photon controlled two-photon not gate, where polarization modes of photons act as quantum bits, aiming to construct the practical and scalable quantum logic circuits. By adopting one-time nondestructive measurement, this gate can realize the function of two two-photon controlled-not gates, where the polarization bits of two target photons will be flipped when the controlled photon is in the vertical polarization state. After measuring on the coherent state, the suitable operations including swapping of photon states and single-photon transformations are carried out by classical feed forward, conditioned on the measurement outcomes. Simple linear optical elements, and mature techniques containing Homodyne measurement and classical feed forward are applied to enhance the feasibility of the scheme presented here and other scalable logic gates.

Driven by the development of nanophotonics and integrated optics, manipulating polarization of light with metastructures has been extensively studied in recent decades. So far there is still a high demand for more efficient ways to control the polarization state of light with extraordinary performance. In this Letter, we report on constructing multifunctional wave plates with stereo-metastructure arrays (SMAs) by two-photon absorption polymerization. In one frequency range, the SMA can turn the polarization direction of incident linearly polarized (LP) light to its orthogonal direction, acting as a half-wave plate (HWP). In the other frequency range, it converts the LP incident light to circularly polarized (CP) light, acting as a quarter-wave plate (QWP). Such a multifunctional element is expected to possess an energy efficiency as high as 75%. By encoding SMAs with different rotation angles at different spatial areas, we show that SMAs can be applied in imaging and sensing, where the focal-plane-array (FPA) imaging demonstrates patterned contrast following different structural distribution.

The incidence of granulomatous mastitis (GLM) in multiparae as seriously affected the quality of life and breastfeeding of pregnant women after delivery, but the treatment is rarely reported. In this article, the development, healing, and lactation of 13 cases were reported and a retrospective analysis was performed. 10 cases of GLM were treated at the Breast Disease Prevention and Treatment Center of Haidian Maternal & Child Health Hospital of Beijing and 3 cases of GLM were treated in the Breast Department of Weihai Municipal Hospital of Shandong province from February 2017 to May 2019. Among the 13 patients, conservative symptomatic treatment was adopted during pregnancy and lactation: anti-infective therapy consisting of oral cephalosporin antibiotic for patients; ultrasound-guided puncture and drainage of pus or incision and drainage after abscess formation. Observation continued during the sinus tract phase. Postpartum breastfeeding was encouraged, especially on the affected side. In this study, the median healing time was 20 months and the average healing time was 30.4 months in 5 healthy breast lactation cases. In 8 cases of bilateral breast lactation, the median healing time was 30 months and the average healing time was 26.5 months. Linear regression test analysis: whether the affected breast was breast-fed after delivery had no effect on the postpartum wound healing time, P = .792. The wounds of 13 patients healed well after lactation, and none of them recurred since the last follow-up visit. There were no adverse events in all infants. Conservative symptomatic treatment for GLM of multiparous women during pregnancy and lactation and encouraging breastfeeding after delivery have no effect on infant health and the recovery time of patients.

We present a generation proposal of three-photon polarization-entangled decoherence-free states, which are immune to the collective decoherence. Based on weak cross-Kerr nonlinearities, the polarization and spacial entanglement gates are realized, and thus three-photon polarization-entangled decoherence-free states can be produced. According to the outcomes of Homodyne measurement performed in the spacial entanglement gate, one Swap gate is inserted into two paths of the photon 1 to swap its spacial modes, by means of classical feed forward. In addition, in the process for realizing two entanglement gates, unitary transformation operations are performed on the appropriate photons conditioned on the different phase shifts occurred on the coherent states, aiming to obtain the same state under two scenarios of the different path compositions of photons. At the output ports of the circuit, three-photon polarization-entangled decoherence-free states which can be utilized to represent two logical qubits, | 0 〉 L and | 1 〉 L are achieved. Apart from Kerr media, only simple linear optical elements and the classical feed forward techniques are necessary in this proposal, facilitating its practical implementation.

Metalenses possess the extraordinary capability to tailor the wavefront of light with compact metastructures. However, it remains challenging to eliminate chromatic aberration and realize multifunctionality. Here we report an achromatic bifocal metalens (ABM) made of three-dimensional standing nano blocks (SNBs). By introducing a height gradient to SNBs, the ABM can achieve achromatic focusing in the wavelength range of 760–1550 nm with two different focal lengths by merely orthogonally switching the linear polarization of the incident beam. Such an achromatic multi-functional element may have applications in polarization sensing/display and shared-aperture optics design, among many others.

Manipulating the polarization state of light is important in numerous applications in photonics and electromagnetism. Among many possible approaches, plasmonic polarizers have attracted widespread attention, due to their flexibility in structural design and convenience in on-chip integration. The authors demonstrate a VO${}_{2}$-based composite plasmonic nanostructure that can dynamically modulate the polarization of reflected light, via the thermally induced insulator-metal transition of the oxide. The composite structure can also be applied to realize switchable infrared imaging.

Surface plasmons (SPs), the resonance of free electrons on the metal-air interface, may strongly interact with light and generate some extraordinary optical effects. Instead of using conventional planar light excitation, here we excite SPs with a focused electron beam on metallic nanostructures with different geometrical symmetries. With the help of a polarizer and filter in the detection system, we obtain cathodoluminescence (CL) images with different polarizations at certain wavelengths. The maxima in the CL images show that the focused electron beam may efficiently excite luminescence with different polarizations at different spots. Comparing the data collected on the structures with specific geometrical symmetry, we demonstrate that the polarization of the emitted light depends on both the structural symmetry and the excitation location. We suggest that this Letter is enlightening to understand the relationship between the SP resonance on the structure and the emission of CL with different polarizations.

A continuous variable quantum key distribution protocol with entanglement swapping of quasi-Bell entangled coherent states is proposed. As the preliminary step, a sender shares quasi-Bell entangled coherent states with a receiver. After their measurements to distinguish the cases of a zero response, a nonzero even-photon response and an odd-photon response, two legitimate participants fulfill the task of key distribution. The correlations resulting from entanglement swapping of quasi-Bell entangled coherent states and the order rearrangement of transmitted states provide the possibility to protect secret key distribution. In the ideal channel, the success probability increases with the amplitude of the coherent state, and approaches unity when the amplitude of the coherent state is larger than two. However, in the loss channel, the decoherence will introduce error in the generated key, and the error rate increases with the amplitude of the coherent state. When the amplitude of the coherent state is smaller than 0.2 (or so), the error rate approaches zero, although the success probability is less than 0.5 in this case.

In order to improve the forecast accuracy and reliability of wind speed with strong randomness, this paper suggests a method. First, apply square root transformation to the wind speed time series, which is different from familiar normalization. Second, BP neural network is employed to forecast the future wind speed time series. Finally, invert the forecasted time series by the inverse square root transformation. The experiment result shows the effectiveness of the proposed method.

A quantum entanglement distribution protocol of a four-photon χ - type polarization-entangled state is presented by exploiting spatial degree of freedom, which is immune to an arbitrary collective noise. This protocol can be fulfilled with nearly unitary probability by the assistance of Homodyne measurement (Y quadrature measurement) that determines the polarization part of the four photons in the transmitted process. Transforming the polarization entanglement mode to spatial entanglement mode and back, the distribution of this entangled state can overcome the influence of collective noise. Moreover, the combination of currently available optical elements is exploited in this protocol, which includes polarization beam splitters, reflection mirrors, optical detectors, and half wave plates functioning as the NOT gates, etc.