Search

Up to an estimated 10% of women experience miscarriage in their lifetimes. Embryonic aneuploidy is a leading cause for miscarriage, infertility and congenital defects. Here we identify variants of ELL3, a gene encoding a transcription elongation factor, in couples who experienced consecutive early miscarriages due to embryonic aneuploidy. Maternal ELL3 knockout leads to mouse oocyte aneuploidy, subfertility and miscellaneous embryonic defects. Mechanistically, we find that ELL3 localizes to the spindle during meiosis, and that ELL3 depletion in both mouse and human oocytes increases the incidence of meiotic spindle abnormality. ELL3 coordinates with TPX2 to ensure the proper function of the microtubule motor KIF11. Live imaging analysis shows that ELL3 is paramount for promoting spindle assembly and driving chromosome movement. Together, our findings implicate maternal ELL3 deficiency in causing oocyte aneuploidy and early miscarriage.

Objective: The Jiangmen Underground Neutrino Observatory, which is currently being constructed in South China, will be a cutting-edge liquid scintillator detector for neutrino physics in the coming decade. The read-out electronics will be installed in close proximity to the large photomultipliers and directly inside the water pool surrounding the detector. Once installed, these electronics will not be accessible for repair or replacement; therefore, ensuring their reliability is of utmost importance. A crucial aspect of this reliability analysis involves evaluating the failure rate of custom-designed analog-to-digital converter and front-end chips used in underwater read-out electronics. Methods: The Arrhenius model shall be utilized to compute the reliability failure rate value. During ageing, the ambient temperature of the setup system was set at 115 °C. The high-gain and low-gain output channels were chosen as references for detecting failures in the tested sample for front-end chips of Jiangmen Underground Neutrino Observatory, while for analog-to-digital converters, effective number of bits are considered as reference parameters. Results: After ageing, all chips were re-measured. The ADC and FEC tests revealed no failures. As a result, the upper limit for the failure rate of front-end chips is 0.43 failures in time, and the upper limit for analog-to-digital converters is 0.42 failures in time at 30 °C. Conclusion: The reliability test result shows that custom-designed chips can be used in underwater read-out electronics of Jiangmen Underground Neutrino Observatory.

Improving the supply-demand balance of ecosystem services (SDBES) from the perspective of land use is essential for managing regional ecosystem and realizing sustainable development. By combining land use with the supply and demand of ecosystem services (SDES), a technical framework for defining land use threshold and optimizing its structure to improve the SDBES state was constructed and applied to a practical case. The spatial pattern of supply and demand of each ES in Lancang county was distinctly heterogeneous, with significant differences in SDES across different land use types. Strong spatial heterogeneity existed in the ESDR of each ES at the grid scale, and the areas of deficit were ranked as carbon sequestration > water conservation > habitat quality > food production. The structure of dry land, paddy field, tea, evergreen broad-leaved forest, grassland, urban construction land, and industrial and mining construction land were the focus of land use optimization. Based on the land use area thresholds under the SDBES, the optimal land use structure for maximizing comprehensive benefits contributed to a balanced relationship between SDES and promoted sustainable regional development. The study provides a new perspective and method for improving the SDBES state, alleviating land conflicts, and managing ecological environment.

The electrochemical reduction of carbon dioxide to useful chemicals and fuels is a new strategy to utilize large amounts of carbon dioxide. However, the lack of efficient catalysts has hindered the development of this technology. Herein, a machine learning (ML)-assisted screening model is developed to explore efficient trimetallic electrocatalysts for the CO2reduction reaction by combining with density functional theory (DFT) and electrochemical experiments. The group of doped elements in the periodic table is the most important descriptor of Cu-based trimetallic electrocatalysts and the support vector regression algorithm has the best predictive performance. Based on ML predictions, the overpotential of PdPt@Cu is successfully predicted to be 0.11 V, and it shows the best electrocatalytic performance for the CO2reduction reaction (CO2RR). DFT calculation results show that CO2→ COOH* is the potential-limiting step of CO2RR-to-CO for PdPt@Cu and its overpotential is 0.09 V, which is consistent with the ML-predicted results. The electrochemical experiments show that the Faraday efficiency of CO is 82.12% at −0.8 V vs RHE for PdPt@Cu. After 12 h of electrolysis in the H-cell, the catalyst still maintains good catalytic performance. This work provides an efficient method for screening catalysts.

Aneuploidy, the presence of a chromosomal anomaly, is a major cause of spontaneous abortions and recurrent pregnancy loss in humans. However, the underlying molecular mechanisms still remain poorly understood. Here, we report that ARHGAP26, a putative tumor suppressor gene, is a newly identified regulator of oocyte quality to maintain mitochondrial integrity and chromosome euploidy, thus ensuring normal embryonic development and fertility. Taking advantage of knockout mouse model, we revealed that genetic ablation of Arhgap26caused the oocyte death at GV stage due to the mitochondrial dysfunction-induced ROS accumulation. Lack of Arhgap26 also impaired both in vitro and in vivo maturation of survived oocytes which results in maturation arrest and aneuploidy, and consequently leading to early embryonic development defects and subfertility. These observations were further verified by transcriptome analysis. Mechanistically, we discovered that Arhgap26 interacted with Cofilin1 to maintain the mitochondrial integrity by regulating Drp1 dynamics, and restoration of Arhgap26 protein level recovered the quality of Arhgap26-null oocytes. Importantly, we found an ARHGAP26mutation in a patient with history of recurrent miscarriage by chromosomal microarray analysis. Altogether, our findings uncover a novel function of ARHGAP26 in the oocyte quality control and prevention of aneuploidy and provide a potential treatment strategy for infertile women caused by ARHGAP26mutation.

Multi-robot cooperative navigation is an important task, which has been widely studied in many fields like logistics, transportation, and disaster rescue. However, most of the existing methods either require some strong assumptions or are validated in simple scenarios, which greatly hinders their implementation in the real world. In this paper, more complex environments are considered in which robots can only acquire local observations from their own sensors and have only limited communication capabilities for mapless collaborative navigation. To address this challenging task, we propose a hierarchical framework, by fusing both Sensor-wise and Agent-wise features for Perception-Improving (SAPI), which can adaptively integrate features from different information sources to improve perception capabilities. Specifically, to facilitate scene understanding, we assign prior knowledge to the visual coder to generate efficient embeddings. For effective feature representation, an attention-based sensor fusion network is designed to fuse sensor-level information of visual and LiDAR sensors, while graph convolution with multi-head attention mechanism is applied to aggregate agent-level information from an arbitrary number of neighbors. In addition, reinforcement learning is used to optimize the policy, where a novel compound reward function is introduced to guide training. Extensive experiments demonstrate that our method has excellent generalization ability in different scenarios and scalability for large-scale systems.

Cover crop cultivation is a soil management practice to increase orchard sustainability. This study aimed to clarify the effects of eight cover crop treatments on weed control and soil qualities in the citrus orchard. The present study used coverage, soil physical properties, nutrient contents, enzyme activities, and soil bacterial community of eight cover crop species (February orchid, Chinese milk vetch, white clover, common vetch, perennial ryegrass, rattail fescue, white clover + perennial ryegrass, perennial ryegrass + tall fescue + orchardgrass + annual meadow grass) and a control (clean tillage) to characterize the impact of treatment on soil for 1 year. White clover, common vetch, rattail fescue, and the white clover + perennial grass mixture showed the high percentage coverage to control weeds. The rattail fescue treatment allowed significantly increased soil porosity. Fabaceae showed a distinct effect to increased soil organic matter content, which was reduced in soil planted with cereal species. In all cover crop treatments, bacterial and fungal diversity generally increased compared to the control treatment. Redundancy analysis indicated that soil organic matter content and available nitrogen, phosphorus, and potassium contents were the most important environmental factors that influence microbial communities. Among the different cover crop species, white clover, common vetch, rattail fescue, and mixed-species treatment comprising white clover plus perennial ryegrass showed promise for weed control. Compared with the clean tillage applied herbicide, soil qualities in cover crop soil generally showed increasing trends especially soil physical properties and microbial diversity.

The concept of metamaterials offers a flexible pathway to manipulate the macroscopic behavior of light by delicately designed microscopic subwavelength structures, which has been recently introduced to integrated photonics to create devices with ultra-compact footprint, excellent performance or versatile functionalities. However, the conventional design approach of metamaterials, including two separated steps of subwavelength structure design and the assembly of unit cells, often encounters challenges when facing extreme design targets. In this work, we propose a hierarchical inverse design approach by cascading a conventional unit-cell-based design with a holistic topology optimization. As a proof-of-concept, we demonstrate ultra-short-range light focusing and mode-size conversion enabled by on-chip meta-lenses. The shortening of tapering region pushes higher numerical aperture of on-chip lenses, leading to the violation of locally periodic approximation used in meta-lens design and thus poor device performance, which fortunately, can be well compensated by the follow-up holistic optimization step. We experimentally realize mode-size squeezing by almost 20 times in a tapering region as short as 8 μm and 5 μm with low insertion loss and broadband performance. The proposed design scheme provides practical guidelines to design metamaterials as flexible on-chip wavefront control and light routing devices for various applications in fiber communication, sensing and optical computing.

This article presents observational results of the vertical structural evolution of ionospheric holes during two rocket launches. A combination of observations from the newly built Sanya incoherent scatter radar (SYISR) and Global Navigation Satellite System networks was employed. The vertical structural evolution of two rocket‐induced ionospheric holes over the SYISR could be divided into three stages. Firstly, 10–11 min after launch, the holes initially appeared in the topside ionosphere. Then, the holes expanded rapidly toward higher and lower altitudes. At ∼30 min after launch, the holes extended to an altitudinal range of ∼200 km to over 700 km. The maximum depletion altitude was 425 km for the afternoon event and 283 km for the midnight event. Finally, the holes recovered slowly, with faster recovery at higher altitudes. Our work contributes to further understanding the vertical structural evolutionary mechanisms of the ionospheric holes and relevant ionospheric processes. When rockets fly in the ionosphere, numerous H2O or H2molecules in the rocket exhaust rapidly react with the O+in the background ionosphere and produce positive ions, which then react with electrons and lead to a large electron depletion known as ionospheric holes. The vertical structure of these holes has rarely been observed before. In this study, we observed the full vertical profile and the complete vertical structural evolution of two rocket‐induced ionospheric holes, using the newly built Sanya incoherent scatter radar (SYISR), combined with the Global Navigation Satellite System networks for their horizontal features. These two ionospheric holes occurred in the afternoon and around midnight in local time, with maximum electron depletion of 15% and 83% relative to the background ionosphere, and altitudinal distribution of 255–775 km and 202–535 km over SYISR, respectively. The vertical structural evolution of the holes displays the vertical variations of ionospheric characteristics and crucial ionospheric processes like plasma transport and chemistry. Our study contributes to a deeper understanding of the dynamics process of ionospheric holes as an artificial space weather process, which is of potential significance for monitoring space objects such as rockets. Observations of the full vertical profile of the rocket‐induced ionospheric holes were presentedThe holes first appeared in topside ionosphere and then expanded both upwards and downwards to an altitude range of ∼200–∼700 kmThe recovery of electron density is faster for the midnight hole than the daytime one and is faster at high altitude than at low altitude Observations of the full vertical profile of the rocket‐induced ionospheric holes were presented The holes first appeared in topside ionosphere and then expanded both upwards and downwards to an altitude range of ∼200–∼700 km The recovery of electron density is faster for the midnight hole than the daytime one and is faster at high altitude than at low altitude

Many leading countries are boosting renewables, especially solar energy, as a major way to mitigate future energy crises and climate change. Particularly, in China, the number and scale of photovoltaic (PV) power stations have grown unprecedentedly in the last decade. There is an urgent need to monitor the PV power development in order to accurately estimate national renewable potentials and understand the ecological impacts. However, there are few efforts towards providing spatially explicit and time-series datasets of PV development at the regional and national scales. To fill the gap, this study proposes an integrated remote sensing approach for PV power stations mapping by combining image segmentation and object-based classification (ISOC) techniques. We took five northwestern provinces of China as an illustration and produced 30-m medium-resolution PV power station distribution maps from 2007 to 2019. Our analysis shows that the total area of PV power stations in the five provinces increased to 722 km 2in 2019, with producer, user and overall accuracies of 86%, 100% and 93%. Of the 309 PV station clusters (hereafter, PV parks), the top 7% largest ones account for 61% of the total area of PV power stations, indicating that PV power stations in the Northwest tend to be developed in the form of large-scale centralized PV parks. The land used for PV power stations was mainly converted from four land cover types: Gobi Desert, sandy land, sparse grassland, and moderate grassland. The central government policy on facilitating clean energy played a major role in driving the rapid expansion of PV parks across the country. The methodology and results of this study will help policymakers, researchers, and practitioners to develop corresponding industrial standards and environmental regulations to mitigate the potential environmental impacts, and promote more sustainable development of solar energy in China and beyond.

AbstractCorporate social responsibility (CSR) has been widely accepted as essential for sustainable development and, with the occurrence of such disasters as food quality scandals and building collapses, its importance has been increasingly recognised in China over the past decade. At the same time, despite property development being frequently linked in the mass media with unaffordable housing prices, bribery, and poor construction quality, many large developers have instituted programmes to improve their CSR presence. However, the perceptions of property development organisations of what CSR means to them are as yet unclear. The aim of this paper, therefore, is to better understand the way CSR is seemingly perceived by property developers in China. This is undertaken by analysing CSR disclosure and prioritising information from CSR corporate reports by developers in the housing sector. Three attributes of CSR disclosure information type, responsibility type, and stakeholder type are used to construct an analytical framework for testing of 44 published company reports by content analysis. The findings indicate a greater emphasis on management approaches and ethical responsibilities than commercial goals, with industry and ownership differences pointing to the need to be recognised by the public and future decision-makers.

Under the requirements of China's strategic goal of "carbon peaking and carbon neutrality", as a renewable, clean and efficient secondary energy source, hydrogen benefits from abundant resources, a wide variety of sources, a high combustion calorific value, clean and non-polluting, various forms of utilization, energy storage mediums and good security, etc. It will become a realistic way to help energy, transportation, petrochemical and other fields to achieve deep decarbonization, and will turn into an important replacement energy source for China to build a modern clean energy system. It is clear that accelerating the development of hydrogen energy has become a global consensus. In order to provide a theoretical support for the accelerated transformation of hydrogen-related industries and energy companies, and provide a basis and reference for the construction of "Hydrogen Energy China", this paper describes main key technological progresses in the hydrogen industry chain such as hydrogen production, storage, transportation, and application. The status and development trends of hydrogen industrialization are analyzed, and then the challenges faced by the development of the hydrogen industry are discussed. At last, the development and future of the hydrogen industry are prospected. The following conclusions are achieved. (1) Hydrogen technologies of our country will become mature and enter the road of industrialization. The whole industry chain system of the hydrogen industry is gradually being formed, and will realize the leap-forward development from gray hydrogen, blue hydrogen to green hydrogen. (2) The overall development of the entire hydrogen industry chain such as hydrogen production, storage and transportation, fuel cells, hydrogen refueling stations and other scenarios should be accelerated. Besides, in-depth integration and coordination with the oil and gas industry needs more attention, which will rapidly promote the high-quality development of the hydrogen industry system. (3) The promotion and implementation of major projects such as "north-east hydrogen transmission", "west-east hydrogen transmission", "sea hydrogen landing", and utilization of infrastructures such as gas filling stations, can give full play to the innate advantages of oil and gas companies in industrial chain nodes such as hydrogen production and refueling, etc., which can help to achieve the application of "oil, gas, hydrogen, and electricity" four-station joint construction, form a nationwide hydrogen resource guarantee system, and accelerate the planning and promotion of the "Hydrogen Energy China" strategy.

AbstractThe architecture, engineering, and construction (AEC) industry is well known for low productivity, with a critical obstacle being the difficulties associated with understanding the mechanism of job performance. This due to established theories being incapable of capturing and dealing with the complexities associated with construction projects, with extant performance studies falling short in the context of complex projects by not grounding the factors involved in a common conceptual model that articulates the mechanics of job performance. In response, this study builds on person-environment (P-E) fit theory using a stimulus-organism-response paradigm, to develop a foundational conceptual model of the performance-related working behaviors of construction professionals. This study emphasizes the mediating role of P-E fit assessment and integrates key P-E relationships in a simplified framework, with a common layer based on P-E fit assessment factors that both accommodates previous studies and lays a coherent foundation for future studies. The model can also be applied in a reverse, diagnostic, capacity to identify corrective approaches and appropriate management strategies, and is easily adaptable to more general situations beyond the construction industry. Concluding remarks concern the major contributions made and prospects for future development.

Soon after fertilization, the block mechanisms are developed in the zona pellucida (ZP) and plasma membrane of the egg to prevent any additional sperm from binding, penetration, and fusion. However, the molecular basis and underlying mechanism for the post-fertilization block to sperm penetration through ZP has not yet been determined. Here, we find that transglutaminase 2 (Tgm2), an enzyme that catalyzes proteins by the formation of an isopeptide bond within or between polypeptide chains, crosslinks zona pellucida glycoprotein 3 (ZP3) to result in the ZP hardening after fertilization and thus prevents polyspermy. Tgm2 abundantly accumulates in the subcortical region of the oocytes and vanishes upon fertilization. Both inhibition of Tgm2 activity in oocytes by the specific inhibitor in vitro and genetic ablation of Tgm2 in vivo cause the presence of additional sperm in the perivitelline space of fertilized eggs, consequently leading to the polyploid embryos. Biochemically, recombinant Tgm2 binds to and crosslinks ZP3 proteins in vitro, and incubation of oocytes with recombinant Tgm2 protein inhibits the polyspermy. Altogether, our data identify Tgm2 as a participant of zona block to the post-fertilization sperm penetration viahardening ZP surrounding fertilized eggs, extending our current understanding about the molecular basis of block to polyspermy.

Monitoring the generation and movement of equatorial plasma bubbles (EPBs) in a large longitude region is crucial important for better understanding their day‐to‐day variability. Using the newly developed Low lAtitude long Range Ionospheric raDar (LARID) at Dongfang (19.2°N, 108.8°E, dip lat. 13.8°N), China, an extremely long‐range experiment for observing EPB irregularities in a range of ±9,600 km to the radar site was first carried out. The results show that EPB irregularities with ranges up to 7,000 and 9,500 km were observed by the east and west beams of LARID, respectively. By incorporating simultaneous observations from GNSS receiver and ionosonde networks, it is demonstrated that the EPBs generated from post‐sunset to sunrise over a very wide longitude of ∼140°, from Pacific to Africa could be observed by LARID. The results, for the first time, demonstrate the possibility for tracing global EPBs in real time using a few low latitude over‐the‐horizon radars. Equatorial plasma bubble (EPB), which can cause severe ionospheric scintillation, is an important space weather phenomenon. The occurrence of EPBs exhibits complex longitude variation characteristics. Due to the fact that most of the equatorial and low latitude region is covered by ocean, it is challenging to monitor the generation and movement of global EPBs. Recently, an over‐the‐horizon (OTH) radar at low latitude, that is, the LARID, has been built for observing EPB irregularities. However, it is not clear that how far an OTH radar at low latitude can observe irregularities. This would be very important in the design of a low latitude OTH radar network for tracing global EPB irregularities. To address this issue, an extremely long‐range experiment covering a wide longitude of about 180° was performed for the first time with LARID. The successful observation of EPB irregularities from Pacific to Africa sectors demonstrates the possibility of monitoring the complex longitudinal variations of EPBs by an OTH radar, even during geomagnetic storms. The results provide meaningful insight for building a low latitude OTH radar network in future, that consists of three to four OTH radars could have the capability to obtain global EPBs in real time. First extremely long‐range experiment for observing equatorial plasma bubbles over a large longitude was conductedEquatorial plasma bubbles with ranges as far as 9,500 km were successfully observed by an over‐the‐horizon radarThe results demonstrate the capability for tracing global equatorial plasma bubbles using a few low latitude over‐the‐horizon radars First extremely long‐range experiment for observing equatorial plasma bubbles over a large longitude was conducted Equatorial plasma bubbles with ranges as far as 9,500 km were successfully observed by an over‐the‐horizon radar The results demonstrate the capability for tracing global equatorial plasma bubbles using a few low latitude over‐the‐horizon radars

Nanoelectrospray ionization (nESI) mass spectrometry (MS) is an ideal detection method for microfluidic chips, and its performances depend on nESI emitters. However, the fabrication of monolithic nESI emitters in chips was difficult. Herein, we propose a three-dimensional (3D) printing method to develop a microfluidic nanoelectrospray ionization source (NIS), composed of a nESI emitter and other components. Firstly, the NIS was compatible with a 50 – 500 nL min−1nanoflows by imposing 3D hydrodynamic focusing to compensate for the total flow rate, achieving a 7.2% best relative standard deviation in the total ion current (TIC) profiles. Additionally, it was applied to probe thirteen organic chemicals, insulin, and lysozyme with adequate signal-to-noise ratios and an accuracy of m/zbetween 9.02 × 10−1and 1.48 × 103ppm. Finally, the NIS achieved comparable limits of detection compared with its commercial counterpart. Considering the standardized preparation of NIS, it would be a potential option to develop 3D-printed customized Chip-MS platforms.

The newly released Donghong kiwifruit is a promising commercial cultivar. The dynamic changes of major phenolic compounds (flavonols, flavanols, phenolic acids, and anthocyanins) during the representative stages of fruit development and ripening of the Donghong kiwifruit were determined by high-performance liquid chromatography. The corresponding time-course transcriptional changes were evaluated using the combined analysis of RNA-Seq and qRT-PCR. The most predominant phenolic compound in the Donghong kiwifruit was epicatechin. Cyanidin 3-O-[2-O-(β-xylosyl)-β-galactoside] and cyanidin 3-O-β-galactoside were two essential anthocyanins detected. Candidate genes and pathways involved in phenolic compounds biosynthesis were highlighted. The structural genes (AcLDOX2, Ac5GGT1, and Ac5AT2) and the transcription factor (bHLH74-2) were strongly associated with anthocyanin biosynthesis. AcMYB4-1 may be a novel transcription factor that reduces anthocyanin accumulation. Results from the study may be a very useful supplement to current knowledge of molecular mechanisms to elucidate coloration in the red-fleshed kiwifruit and could help breeders modify the kiwifruit germplasm.

ABSTRACTThe role of exogenous methyl jasmonate (MeJA) in alleviating drought stress was investigated on Huangguogan. Except for intercellular CO2concentration, MeJA had little effect on net photosynthetic rate, stomatal conductance, and transpiration rate under drought stress. Compared with drought stress, MeJA significantly alleviated the decrease of chlorophyll content. However, chlorophyll a/bratio was significantly increased. MeJA significantly increased proline and soluble sugar contents, significantly decreased the O2−·and H2O2levels, and increased SOD and POD activities. In addition, the MDA content of drought stress was the highest of all treatments. MeJA significantly reduced MDA content in drought-stressed Huangguoganleaves. Although the Ascorbic acid (AsA) contents of 500 and 1000 mg L−1MeJA treatments were lower than that of 250 mg L−1MeJA, but all concentration of MeJA treatments delayed the decline of AsA content. Therefore, MeJA could induce drought stress tolerance by increasing the osmotic adjustment substances and antioxidant activities.

Dielectric metamaterials with high refractive indices may have an incredible capability to manipulate the phase, amplitude, and polarization of the incident light. Combining the high refractive index and the excellent electrical characteristics of the hybrid organic-inorganic perovskites (HOIPs), for the first time we experimentally demonstrate that metamaterial made of HOIPs can trap visible light and realize effective photon-to-electron conversion. The HOIP metamaterials are fabricated by focused ion beam milling on a solution-grown single-crystalline HOIP film. The optical absorption is significantly enhanced at the visible regime compared to that of the flat HOIP film, which originates from the excited Mie resonances and transverse cavity modes with inhibited interface reflection. Furthermore, compared to the flat film, the HOIP metamaterial shows increased photocurrent of up to ~40%, where the effective photocarrier generation efficiency increases by ~40% and the related internal efficiency by ~20%. Our data point to the potential application of HOIP metamaterials for high-efficiency light trapping and photon-to-electron conversion.

Integrating light field microscopy techniques with existing miniscope architectures has allowed for volumetric imaging of targeted brain regions in freely moving animals. However, the current design of light field miniscopes is limited by non-uniform resolution and long imaging path length. In an effort to overcome these limitations, this paper proposes an optimized Galilean-mode light field miniscope (Gali-MiniLFM), which achieves a more consistent resolution and a significantly shorter imaging path than its conventional counterparts. In addition, this paper provides a novel framework that incorporates the anticipated aberrations of the proposed Gali-MiniLFM into the point spread function (PSF) modeling. This more accurate PSF model can then be used in 3D reconstruction algorithms to further improve the resolution of the platform. Volumetric imaging in the brain necessitates the consideration of the effects of scattering. We conduct Monte Carlo simulations to demonstrate the robustness of the proposed Gali-MiniLFM for volumetric imaging in scattering tissue.

Luminescence lifetime imaging systems are typically complex and expensive instruments targeting bench-top applications. We present a low-cost approach for video frame rate luminescence lifetime imaging on the microsecond scale based on a cellphone camera. The luminescence lifetime is mapped by measuring the phase shift of optical fringes captured by a camera with an electronic rolling shutter at 30 frames per second. Luminescence lifetime imaging is validated by observing a platinum(II)-5,10,15,20-tetrakis-(2,3,4,5,6-pentafluorphenyl)-porphyrin (PtTFPP)/polystyrene film with a non-uniform lifetime distribution. The experimental results indicate a lifetime resolution of 580 ns when a lifetime of 22 µs is measured. This device is portable, low in cost, and shows potential in point-of-care diagnostic and environment applications that measure long-lifetime luminescence.

ABSTRACTIn mammalian cells, cohesin acetyltransferases Esco1 and Esco2 acetylate cohesin subunit Smc3 to establish chromosome cohesion, ensuring the accurate chromosome segregation. However, we have previously documented that both Esco1 and Esco2 have unique substrates and roles in mouse oocyte meiosis I to orchestrate the meiotic progression, but whether these functions are conserved among species is still not determined. Here, we used porcine oocytes as a model to illustrate that Esco1 and Esco2 exerted conserved functions during oocyte meiosis. We observed that Esco1 and Esco2 exhibited different localization patterns in porcine oocytes. Esco1 was localized to the spindle apparatus while Esco2 was distributed on the chromosomes. Depletion of Esco1 by siRNA microinjection caused the meiotic arrest by showing the reduced frequency of first polar body extrusion and defective spindle/chromosome structure. In addition, Esco1 bound to α-tubulin and was required for its acetylation level to maintain the microtubule dynamics. By contrast, depletion of Esco2 by siRNA microinjection resulted in the accelerated meiotic progression by displaying the precocious polar body extrusion and inactivation of spindle assembly checkpoint. Notably, Esco2 was shown to be associated with histone H4 for the acetylation of H4K16 to modulate the kinetochore function. Collectively, our data reveal that Esco1 and Esco2 perform distinct and conserved functions in oocytes to drive the meiotic progression beyond their canonical roles in the cohesion establishment.

With the concept of metamaterials introduced into integrated photonics, subwavelength structures have gained popularity for their ability to create devices with ultra-compact size, high performance, and versatile functionalities. However, traditional metamaterial design methods are usually based on empirical templates and physical approximations, lacking the ability to design free-form metamaterial structures and optimize entire devices globally. In this work, we propose a hierarchical inverse design approach that combines a conventional effective refractive index based metamaterial structures design with a follow-up global topology optimization. The empirical metamaterial grating coupler design based on effective refractive index engineering faces inaccurate index extraction and insufficient approximation of wavevector matching conditions, which deteriorates coupling efficiency, especially for fully-etched devices with the decreased tapering region. Fortunately, a subsequent overall topology optimization step can well compensate for the negative effect of the shrinking device footprint to increase the efficiency of the metamaterial grating coupler. We demonstrate a 23 μm×10 μm ultra-compact metamaterial grating coupler with single-step-etched to couple light between a fiber and a 500 nm single-mode silicon waveguide in the O-band. Experimental measurement shows an insertion loss of 3.17 dB and a 3 dB bandwidth of 77 nm, making it the smallest footprint device ever reported.

Deep learning–reconstructed turbo spin-echo (TSE) MRI led to reduced examination time and improved image quality with similar diagnostic confidence compared with standard TSE MRI in the shoulder.

Magnetic polariton (MP) that couples electromagnetic waves with magnetic excitation can be predicted by equivalent inductor-capacitor (LC) circuit model. However, when the resonance frequencies of MP and surface phonon polariton (SPhP) is close, the absorption and transmission peak predicted by LC circuit model are far different from solving electromagnetic field calculation results. In this work, absorption and transmission enhancement with a SiC slit array are theoretically demonstrated within the SiC phonon absorption band with Finite-difference time-domain (FDTD) method. The interactions between SPhP and MP are confirmed by electromagnetic field distributions. Mutual inductor-inductor-capacitor (MLC) circuit model is employed to predict the multi-order MP resonance conditions and the coupling between MP and SPhP is treated as a mutual inductor in MLC model. The geometric effects of SiC slit arrays are investigated and MLC circuit model works well. This study may contribute to the design and prediction of thermal radiative properties and micro/nanostructures metamaterials thermal radiative properties database building.

By combining a pulsed laser ablation vanadium atom (V) beam source with the two-color laser sequential electric field pulse scheme for pulse field ionization-photoion (PFI-PI) detection, we have developed a quantum spin–orbit state selected transition metal ion source for ion–molecule reaction studies. As a demonstration, we show that the V+ion can be prepared in the single spin–orbit levels of its three lowest quantum electronic states, V+[a5DJ(J= 0–4), a5FJ(J= 1–5), and a3FJ(J= 2–4)], achieving laboratory kinetic energy (Elab) resolutions of ≤0.2 eV. The precursor V atom beam is first excited to high-nRydberg states by resonance-enhanced visible–ultraviolet laser photoexcitation via the V*[3d3(4F) 4s4p (3P°)] neutral intermediate state. The total photon energy is tuned in the regions from 54 380 to 63 520 cm–1to cover the photoionization energies for the formation of these spin–orbit states. Sharp Rydberg transitions converging to the V+[a5DJ(J= 1 and 2)] spin–orbit levels are identified in the respective PFI-PI spectra for the V+[a5DJ(J= 0 and 1)] states. The analysis of these Rydberg members observed yields an ionization energy of 54 412.65 ± 0.15 cm–1for V atom, which is in excellent accord with the literature value of 54 413 ± 1 cm–1eV. In order to understand the profile for the PFI-PI spectrum of V+ion observed and thus obtain reliable Stark shift corrections by using the sequential PFI-PI detection scheme, we have also examined the PFI-PI spectrum for Ar+(2P3/2) in detail by varying the retarding as well as the PFI electric field pulses.