Real-time channel selection in multi-mode multiplexing optical interconnection implemented by hybrid algorithm and material system.

Multi-mode multiplexing optical interconnection (MMOI) has been widely used as a new technology that can significantly expand communication bandwidth. However, the constant-on state of each channel in the existing MMOI systems leads to serious interference for receivers when extracting and processing information, necessitating introducing real-time selective-on function for each channel in MMOI systems. To achieve this goal, combining several practical requirements, we propose a real-time selective mode switch based on phase-change materials, which can individually tune the passing/blocking of different modes in the bus waveguide. We utilize our proposed particle swarm optimization algorithm with embedded neural network surrogate models (NN-in-PSO) to design this mode switch. The proposed NN-in-PSO significantly reduces the optimization cost, enabling multi-dimensional simultaneous optimization. The resulting mode switch offers several advantages, including ultra-compactness, rapid tuning, nonvolatility, and large extinction ratio. Then, we demonstrate the real-time channel selection function by integrating the mode switch into the MMOI system. Finally, we prove the fabricating robustness of the proposed mode switch, which paves the way for its large-scale application.

Multifunctional emitter based on inverse design for infrared stealth, thermal imaging and radiative cooling.

In contrast to conventional emitters fashioned from traditional materials, tunable thermal emitters exhibit a distinct propensity to fulfill the demands of diverse scenarios, thereby engendering an array of prospects within the realms of communications, military applications, and control systems. In this paper, a tunable thermal emitter without continuous external excitation is introduced using Ge2Sb2Te5 (GST) and high-temperature-resistant material Mo. It is automatically optimized by inverse design with genetic algorithm (GA) to switch between different functions according to the object temperature to adapt to diverse scenarios. In "off" mode, the emitter orchestrates a blend of infrared (IR) stealth and thermal management. This is evidenced by average absorptivity values of 0.08 for mid-wave infrared (MIR, 3-5 µm), 0.19 for long-wave infrared (LIR, 8-14 µm), and 0.68 for the non-atmospheric window (NAW, 5-8 µm). Conversely, when confronted with high-temperature entities, the emitter seamlessly transitions to "on" mode, instigating a process of radiative cooling. This transformation is reflected in the augmented emissivity of the dual-band atmospheric window including MIR and LIR, attaining peak values of 0.96 and 0.97. This transition yields a cooling potential, quantified at 64 W/m2 at the ambient temperature of 25°C. In addition, our design employs a layered structure, which avoids complex patterned resonators and facilitates large-area fabrication. The emitter in this paper evinces robust insensitivity to polarization variations and the angle of incidence. We believe that this work will contribute to the development in the fields of dynamic tunability for IR stealth, dynamic radiative cooling systems, and thermal imaging.

The extracellular polysaccharide inhibit porcine epidemic diarrhea virus with extract and gene editing Lacticaseibacillus.

Lacticaseibacillus is one of the predominant microorganisms in gut from human and animal, and the lacticaseibacillus have effective applications against the viral diarrhea of piglets in the farm. However, the function and the concrete cell single pathways of the active ingredient from lacticaseibacillus was not clear within anti-infection in the postbiotics research. Here, we compared the biological function of extracellular polysaccharides (EPS) purified from lacticaseibacillus casei (L. casei) and gene editing lacticaseibacillus casei with the CRISPER-Cas9 technology, which were with the ability of antioxidation and anti-inflammation, and the EPS could also inhibit the ROS production within the Porcine Small Intestinal Epithelial Cells-J2 (IPEC-J2). Interestingly, we found that both of EPS and genome editing lacticaseibacillus casei could specifically target the IFN-λ expression in the IPEC-J2, which was beneficial against the PEDV infection in the virus replication and production with the qRT-PCR and indirect immunofluorescence methods. Finally, the STAT3 cell single pathway was stimulated to transcribe IFN-λ with the EPS to elucidate the detailed mechanism of activating type III IFN signals receptor of IL-10R2, which play the function between anti-inflammation and anti-virus in the PEDV infection. Taken together, our research linked a postbiotics of EPS with the antiviral infection of PEDV, which suggest that the lacticaseibacillus itself still have displayed the potential immunomodulatory activities, and highlight the immunomodulatory potential of EPS-producing microbes.

Optical transparent metamaterial with multi-band compatible camouflage based on inverse design.

Infrared (IR) thermal camouflage and management are deeply desirable in the field of military and astronomy. While IR compatible with laser camouflage technology is extensively studied to counter modern detection systems, most existing strategies for visible light camouflage focus on color matching, which is not suitable for scenarios requiring transparency. In this work, we propose an optically transparent metamaterial with multi-band compatible camouflage capability based on the inverse design. The metamaterial consists of Ag grating, Si3N4 dielectric spacer layer, Ag reflection layer, and Si3N4 anti-reflective layer. An ideal multi-band compatible spectrum is involved in the inverse design algorithm. Calculated results demonstrate high transmittance (T0.38-0.78µm = 0.70) in the visible region, low reflectance (R1.55µm = 0.01) in laser working wavelength, high reflectance (R3-5µm = 0.86 and R8-14µm = 0.92) in the dual-band atmospheric window, and high emissivity (ɛ5-8µm = 0.61) for the non-atmospheric window. The radiative heat flux in the detected band is 31W/m2 and 201W/m2 respectively. Furthermore, the incident and polarized insensitivity of the proposed metamaterial supports applicability for practical situations. This work, emphasizes an effective strategy for conducting optically transparent design with compatible IR-laser camouflage as well as radiative cooling properties by an automated design approach.

Loss in the Antibacterial Ability of a PyrR Gene Regulating Pyrimidine Biosynthesis after Using CRISPR/Cas9-Mediated Knockout for Metabolic Engineering in Lactobacillus casei.

Lactobacillus casei (L. casei) has four possible mechanisms: antimicrobial antagonism, competitional adhesion, immunoregulation, and the inhibition of bacterial toxins. To delineate the metabolic reactions of nucleotides from L. casei that are associated with mechanisms of inhibiting pathogens and immunoregulation, we report that a PyrR-deficient L. casei strain was constructed using the CRISPR-Cas9D10A tool. Furthermore, there were some changes in its basic biological characterization, such as its growth curve, auxotroph, and morphological damage. The metabolic profiles of the supernatant between the PyrR-deficient and wild strains revealed the regulation of the synthesis of genetic material and of certain targeting pathways and metabolites. In addition, the characteristics of the PyrR-deficient strain were significantly altered as it lost the ability to inhibit the growth of pathogens. Moreover, we identified PyrR-regulating pyrimidine biosynthesis, which further improved its internalization and colocalization with macrophages. Evidence shows that the PyrR gene is a key active component in L. casei supernatants for the regulation of pyrimidine biosynthesis against a wide range of pathogens.

Inverse-designed ultra-compact multi-channel and multi-mode waveguide crossings.

In this work, we use the inverse design method to design three-channel and four-channel dual-mode waveguide crossings with the design regions of 4.32 µm-wide regular hexagon and 6.68 µm-wide regular octagon, respectively. Based on the highly-symmetric structures, the fundamental transverse electric (TE0) and TE1 modes propagate through the waveguide crossings efficiently. Moreover, the devices are practically fabricated and experimentally characterized. The measured insertion losses and crosstalks of the three-channel and dual-mode waveguide crossing for both the TE0 and TE1 modes are less than 1.8 dB and lower than -18.4 dB from 1540 nm to 1560 nm, respectively. The measured insertion losses of the four-channel and dual-mode waveguide crossing for the TE0 and TE1 modes are less than 1.8 dB and 2.5 dB from 1540 nm to 1560 nm, respectively, and the measured crosstalks are lower than -17.0 dB. In principle, our proposed scheme can be extended to waveguide crossing with more channels and modes.

Different-mode power splitters based on a multi-dimension direct-binary-search algorithm.

In this work, we design, fabricate, and characterize a different-mode (waveguide-connected) power splitter ((W)PS) by what we believe to be a novel multi-dimension direct-binary-search algorithm that can significantly balance the device performance, time cost, and fabrication robustness by searching the state-dimension, rotation-dimension, shape-dimension, and size-dimension parameters. The (W)PS can simultaneously generate the fundamental transverse electric (TE0) and TE1 mode with the 1:1 output balance. Compared with the PS, the WPS can greatly shorten the adiabatic taper length between the single-mode waveguide and the grating coupler. The measured results of the different-mode (W)PS indicate that the insertion loss and crosstalk are less than 0.9 (1.3) dB and lower than -17.8 (-14.9) dB from 1540 nm to 1560 nm. In addition, based on the tunable tap couplers, the different-mode (W)PS can be extended to multiple output ports with different modes and different transmittances.

Biogenic Imaging Contrast Agents.

Imaging contrast agents are widely investigated in preclinical and clinical studies, among which biogenic imaging contrast agents (BICAs) are developing rapidly and playing an increasingly important role in biomedical research ranging from subcellular level to individual level. The unique properties of BICAs, including expression by cells as reporters and specific genetic modification, facilitate various in vitro and in vivo studies, such as quantification of gene expression, observation of protein interactions, visualization of cellular proliferation, monitoring of metabolism, and detection of dysfunctions. Furthermore, in human body, BICAs are remarkably helpful for disease diagnosis when the dysregulation of these agents occurs and can be detected through imaging techniques. There are various BICAs matched with a set of imaging techniques, including fluorescent proteins for fluorescence imaging, gas vesicles for ultrasound imaging, and ferritin for magnetic resonance imaging. In addition, bimodal and multimodal imaging can be realized through combining the functions of different BICAs, which helps overcome the limitations of monomodal imaging. In this review, the focus is on the properties, mechanisms, applications, and future directions of BICAs.

Three-dimensional mode-division multiplexing system.

Blindly increasing the channels of the mode (de)multiplexer on the single-layer chip can cause the device structure to be too complex to optimize. The three-dimensional (3D) mode division multiplexing (MDM) technology is a potential solution to extend the data capacity of the photonic integrated circuit by assembling the simple devices in the 3D space. In our work, we propose a 16 × 16 3D MDM system with a compact footprint of about 100 µm × 5.0 µm × 3.7 µm. It can realize 256 mode routes by converting the fundamental transverse electric (TE0) modes in arbitrary input waveguides into the expected modes in arbitrary output waveguides. To illustrate its mode-routing principle, the TE0 mode is launched in one of the sixteen input waveguides, and converted into corresponding modes in four output waveguides. The simulated results indicate that the ILs and CTs of the 16 × 16 3D MDM system are less than 3.5 dB and lower than -14.2 dB at 1550 nm, respectively. In principle, the 3D design architecture can be scaled to realize arbitrary network complexity levels.

Photocatalytic Three-Component Synthesis of 3-Heteroarylbicyclo[1.1.1]pentane-1-acetates.

Herein, we report a visible-light-induced three-component reaction involving [1.1.1]propellane, diazoates, and various heterocycles for the synthesis of 3-heteroarylbicyclo[1.1.1]pentane-1-acetates. Throughout this reaction, the radicals generated from diazoate species react with [1.1.1]propellane in an addition reaction to form bicyclo[1.1.1]pentane (BCP) radicals that subsequently react with heterocycles, leading to the formation of 1,3-disubstituted BCP acetates. Notably, this methodology exhibits excellent functional group compatibility, high atom economy, and mild reaction conditions, thus facilitating suitable synthetic access to 1,3-disubstituted BCP acetates.

Synthesis of C3-halo substituted bicyclo[1.1.1]pentylamines via halosulfoamidation of [1.1.1]propellane with sodium hypohalites and sulfonamides.

Herein, we report a catalyst-free synthesis of C3-halo substituted bicyclo[1.1.1]pentylamines under mild conditions. The reaction involves the use of sodium hypohalites and sulfonamides to generate N-halosulfonamides in situ, which subsequently undergo radical addition with [1.1.1]propellane to yield the desired products with suitable functional group tolerance.

Visible light-induced gem-difluoroallylation of [1.1.1]propellane to access gem-difluoroallylic bicyclo[1.1.1]pentanes.

Bicyclo[1.1.1]pentanes (BCPs) represent an important compound class often used as linear spacer units to enhance pharmacokinetic profiles in modern drug design. Herein, we report a cascade multicomponent reaction to synthesize gem-difluoroallylic bicyclo[1.1.1]pentanes via visible light-induced defluorinative gem-difluoroallylation of [1.1.1]propellane. In this methodology, sulfonyl radicals generated from sodium arylsulfinates added to [1.1.1]propellane to form BCP radicals were then trapped by α-trifluoromethyl alkenes to form gem-difluoroallylic bicyclo[1.1.1]pentanes. Importantly, our methodology is characterized by mild reaction conditions, wide reactant scope, and suitable functional group tolerance.

Characterization of Growth Secondary Hair in Min Pig Activated by Follicle Stem Cell Stimulated by Wnt and BMP Signaling Pathway.

In China, the national-level protected pig, the Min pig, is characterized by the development of secondary hairs and hair follicles in winter. Factors that dominate the genotype in the growth of secondary hairs are not clear through the concrete cell signaling pathways. This study compared hair phenotypes based on morphological structure, transcriptomics, and potential targeting molecules in the breeds of Min, Berkshire, and Yorkshire pigs. The results indicated that Min pigs have specific characteristics for the growth of secondary hairs compared with the Berkshire and Yorkshire pigs. The transcriptome analyses and quantitative reverse transcription-polymerase chain reaction results revealed that secondary hair growth was activated by follicle stem cells. The specific inhibitors of Wnt and BMP were studied using respective signals. The density of follicles, activity of follicle stem cells, and relative gene expression results have shown that Wnt and BMP stimulate the activity of follicle stem cells, and the Wnt signaling molecule has a significantly better effect than the BMP signaling molecule on stem cells. Wnt and BMP can promote the growth of local secondary hair and gene expression. Therefore, this study was conducted to verify the development mechanisms of secondary hairs, which have potential applications in laboratory animals and comparative medicine.

The Oral Inactivated Porcine Epidemic Diarrhea Virus Presenting in the Intestine Induces Mucosal Immunity in Mice with Alginate-Chitosan Microcapsules.

The porcine epidemic diarrhea virus, PEDV, which causes diarrhea, vomiting and death in piglets, causes huge economic losses. Therefore, understanding how to induce mucosal immune responses in piglets is essential in the mechanism and application against PEDV infection with mucosal immunity. A method of treatment in our research was used to make an oral vaccine that packaged the inactive PEDV with microencapsulation, which consisted of sodium alginate and chitosan, and adapted the condition of the gut in mice. The in vitro release experiment of microcapsules showed that inactive PEDV was not only easily released in saline and acid solutions but also had an excellent storage tolerance, and was suitable for use as an oral vaccine. Interestingly, both experimental groups with different doses of inactive virus enhanced the secretion of specific antibodies in the serum and intestinal mucus, which caused the effective neutralization against PEDV in the Vero cell by both IgG and IgA, respectively. Moreover, the microencapsulation could stimulate the differentiation of CD11b+ and CD11c+ dendritic cells, which means that the microencapsulation was also identified as an oral adjuvant to help phagocytosis of dendritic cells in mice. Flow cytometry revealed that the B220+ and CD23+ of the B cells could significantly increase antibody production with the stimulation from the antigens' PEDV groups, and the microencapsulation could also increase the cell viability of B cells, stimulating the secretion of antibodies such as IgG and IgA in mice. In addition, the microencapsulation promoted the expression of anti-inflammatory cytokines, such as IL-10 and TGF-ß. Moreover, proinflammatory cytokines, such as IL-1, TNF-α, and IL-17, were inhibited by alginate and chitosan in the microencapsulation groups compared with the inactivated PEDV group. Taken together, our results demonstrate that the microparticle could play the role of mucosal adjuvant, and release inactivated PEDV in the gut, which can effectively stimulate mucosal and systemic immune responses in mice.

Multispectral camouflage nanostructure design based on a particle swarm optimization algorithm for color camouflage, infrared camouflage, laser stealth, and heat dissipation.

With the development of camouflage technology, single camouflage technology can no longer adapt to existing environments, and multispectral camouflage has attracted much research focus. However, achieving camouflage compatibility across different bands remains challenging. This study proposes a multispectral camouflage metamaterial structure using a particle swarm optimization algorithm, which exhibits multifunctional compatibility in the visible and infrared bands. In the visible band, the light absorption rate of the metamaterial structure exceeds 90%. In addition, color camouflage can be achieved by modifying the top cylindrical nanostructure to display different colors. In the infrared band, the metamaterial structure can achieve three functions: dual-band infrared camouflage (3-5 µm and 8-14 µm), laser stealth (1.06, 1.55, and 10.6 µm), and heat dissipation (5-8 µm). This structure exhibits lower emissivity in both the 3-5-µm (ɛ=0.18) and 8-14-µm (ɛ=0.27) bands, effectively reducing the emissivity in the atmospheric window band. The structure has an absorption rate of 99.7%, 95.5%, and 95% for 1.06, 1.55, and 10.6 µm laser wavelengths, respectively. Owing to its high absorptivity, laser stealth is achieved. Simultaneously, considering the heat dissipation requirements of metamaterial structures, the structural emissivity is 0.7 in the non-atmospheric window (5-8 µm), and the heat can be dissipated through air convection. Therefore, the designed metamaterial structure can be used in military camouflage and industrial applications.

Tunable mid-infrared selective emitter based on inverse design metasurface for infrared stealth with thermal management.

Infrared (IR) stealth with thermal management is highly desirable in military applications and astronomy. However, developing selective IR emitters with properties suitable for IR stealth and thermal management is challenging. In this study, we present the theoretical framework for a selective emitter based on an inverse-designed metasurface for IR stealth with thermal management. The emitter comprises an inverse-designed gold grating, a Ge2Sb2Te5 (GST) dielectric layer, and a gold reflective layer. The hat-like function, which describes an ideal thermal selective emitter, is involved in the inverse design algorithm. The emitter exhibits high performance in IR stealth with thermal management, with the low emissivity (ɛ3-5 µm =0.17; ɛ8-14 µm =0.16) for dual-band atmospheric transmission windows and high emissivity (ɛ5-8 µm =0.85) for non-atmospheric windows. Moreover, the proposed selective emitter can realize tunable control of thermal radiation in the wavelength range of 3-14 µm by changing the crystallization fraction of GST. In addition, the polarization-insensitive structure supports strong selective emission at large angles (60°). Thus, the selective emitter has potential for IR stealth, thermal imaging, and mid-infrared multifunctional equipment.

Synthesis of Imidized Cyclobutene Derivatives by Strain Release of [1.1.1]Propellane.

Herein, we report the metal-free synthesis of imidized methylene cyclobutane derivatives via a strain-release driven addition reaction of [1.1.1]propellane. Using this strategy, the methylene cyclobutyl cation intermediate generated by protonation of [1.1.1]propellane was found to be trapped by nitriles to form a nitrilium ion intermediate, which subsequently reacted with carboxylic acids to produce imidized methylene cyclobutene derivatives via a Mumm-type rearrangement.

Tunable Infrared Detection, Radiative Cooling and Infrared-Laser Compatible Camouflage Based on a Multifunctional Nanostructure with Phase-Change Material.

The nanostructure composed of nanomaterials and subwavelength units offers flexible design freedom and outstanding advantages over conventional devices. In this paper, a multifunctional nanostructure with phase-change material (PCM) is proposed to achieve tunable infrared detection, radiation cooling and infrared (IR)-laser compatible camouflage. The structure is very simple and is modified from the classic metal-dielectric-metal (MIM) multilayer film structure. We innovatively composed the top layer of metals with slits, and introduced a non-volatile PCM Ge2Sb2Te5 (GST) for selective absorption/radiation regulation. According to the simulation results, wide-angle and polarization-insensitive dual-band infrared detection is realized in the four-layer structure. The transformation from infrared detection to infrared stealth is realized in the five-layer structure, and laser stealth is realized in the atmospheric window by electromagnetic absorption. Moreover, better radiation cooling is realized in the non-atmospheric window. The proposed device can achieve more than a 50% laser absorption rate at 10.6 µm while ensuring an average infrared emissivity below 20%. Compared with previous works, our proposed multifunctional nanostructures can realize multiple applications with a compact structure only by changing the temperature. Such ultra-thin, integratable and multifunctional nanostructures have great application prospects extending to various fields such as electromagnetic shielding, optical communication and sensing.

Tunable Color-Variable Solar Absorber Based on Phase Change Material Sb2Se3.

In this paper, a dynamic color-variable solar absorber is designed based on the phase change material Sb2Se3. High absorption is maintained under both amorphous Sb2Se3 (aSb2Se3) and crystalline Sb2Se3 (cSb2Se3). Before and after the phase transition leading to the peak change, the structure shows a clear color contrast. Due to peak displacement, the color change is also evident for different crystalline fractions during the phase transition. Different incident angles irradiate the structure, which can also cause the structure to show rich color variations. The structure is insensitive to the polarization angle because of the high symmetry. At the same time, different geometric parameters enable different color displays, so the structure can have good application prospects.

Photoredox/Iron Dual-Catalyzed Insertion of Acyl Nitrenes into C-H Bonds.

In this work, the use of N-acyloxybenzamides as efficient acyl nitrene precursors under photoredox/iron dual catalysis is reported. The resulting acyl nitrenes could be captured by various types of C-H bonds and S- or P-containing molecules. Mechanism investigations suggested that the formation of the acyl nitrene from the N-acyloxybenzamide occurs by a photoredox process, and it is believed that in this redox process oxidative N-H bond cleavage of the N-acyloxybenzamide occurs prior to reductive N-O bond cleavage of the N-acyloxybenzamide.