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Abstract Atomic clocks with higher frequency stability and accuracy than traditional space-borne atomic clocks are the cornerstone of long-term autonomous operation of space-time-frequency systems. We proposed a space cold atoms clock based on an intracavity cooling scheme, which captures cold atoms at the center of a microwave cavity and then executes in situ interactions between the cold atoms and microwaves. As a result of the microgravity environment in space, the cold atoms can interact with the microwaves for a longer time, which aids in realizing a high-precision atomic clock in space. This paper presents the overall design, operational characteristics, and reliability test results of the space atomic clock based on the intracavity cooling scheme designed for the operation onboard the China space station. In addition, the engineering prototype performance of the space cold atoms microwave clock is also presented. The ground test results for the clock show a fractional frequency stability of 1.1 × 10−12 τ−1/2 reaching 2.5 × 10−15 at 200,000 s, providing solid technical and data support for its future operation in orbit.

Objectives: This study aimed to explore and visualize the relationships among multiple symptoms in patients with Meniere’s disease (MD) and aid clinical nurses in the design of accurate, individualized interventions. Methods: This study included 790 patients with MD at the Eye and ENT Hospital of Fudan University from October 2014 to December 2021. A self-designed symptom checklist was used to assess 15 MD-related symptoms and construct contemporaneous networks with all 15 symptoms in R software. Qgraph package and Fruchterman-Reingold layout were used for network visualization. Bootstrapping methods were performed to assess network accuracy and stability, and three centrality indices were adopted to describe relationships among symptoms. Results: Symptom networks showed good accuracy and stability. “Anxiety and nervousness”(98.2%), “aural fullness”(84.4%) and “tinnitus”(82.7%) were the common symptom in MD patients, while “tinnitus”, “aural fullness” and “decline in word recognition”, were more serious. MD patients with longer disease duration had higher prevalence and severity for all symptoms (P < 0.05). Symptom networks showed good accuracy and stability. “Decline in word recognition,” “fatigue,” and “anxiety and nervousness” were at the center of the symptom networks, which had the largest strength values and closeness. “Decline in word recognition,” “headache,” and “spatial discrimination and poor orientation” were the symptoms with the highest betweenness with the strongest bridging effect. The ≥1-year disease group exhibited higher centralities for “drop attack” and “anxiety and nervousness,” and a lower centrality for “headache” compared with the

Abstract Theobroma cacao, the chocolate tree, is indigenous to the Amazon basin, the greatest biodiversity hotspot on earth. Recent advancement in plant genomics highlights the importance of de novo sequencing of multiple reference genomes to capture the genome diversity present in different cacao populations. In this study, three high-quality chromosome-level genomes of wild cacao were constructed, de novo assembled with HiFi long reads sequencing, and scaffolded using a reference-free strategy. These genomes represent the three most important genetic clusters of cacao trees from the Upper Amazon region. The three wild cacao genomes were compared with two reference genomes of domesticated cacao. The five cacao genetic clusters were inferred to have diverged in the early and middle Pleistocene period, approximately 1.83–0.69 million years ago. The results shown here serve as an example of understanding how the Amazonian biodiversity was developed. The three wild cacao genomes provide valuable resources for studying genetic diversity and advancing genetic improvement of this species.

This article explores the experiences of male and female academics in China's higher education system concerning career progression and examines how they perceive the challenges faced by the opposite gender. Our analysis of interviews with 40 academics from a research university revealed that academics' experience of career progression is informed by gendered divisions of labour at home and work and by gendered role expectations that are prevalent in Chinese culture. Female academics reported performing a disproportionate amount of household work: some felt satisfied with having moderately successful academic careers, whereas others aspired to do more but grappled with the difficulties of doing so. In contrast, male academics mentioned great pressure to pursue promotion and career progression: they reported feeling less work-family stress but were fearful of failing in their role as breadwinners. Male and female academics showed mixed comprehension of each other's plight, but in general, female academics recognised that male academics faced higher career expectations but lower household burdens, and male academics felt that female academics had lower career expectations and many more burdens and constraints. Male academics tended to stress biological and societal reasons for gender differences in Chinese academia, whereas female academics highlighted the power of cultural and social beliefs. We argue that the challenges faced by Chinese academics can only be mitigated if gender-specific promotion paths that recognise men's and women's social roles and obligations are made available.

Abstract Hard X‐rays are needed for non‐destructive nano‐imaging of solid matter. Synchrotron radiation facilities (SRF) provide the highest‐quality images with single‐digit nm resolution using advanced techniques such as X‐ray ptychography. However, the resolution or field of view is ultimately constrained by the available coherent flux. To address this, the beam's incoherent fraction can be exploited using multiple parallel beams in an X‐ray multibeam ptychography (MBP) approach. This expands the domain of X‐ray ptychography to larger samples or more rapid measurements. Both qualities favor the study of complex composite or functional samples, such as catalysts, energy materials, or electronic devices. The challenge of performing ptychography at high energy and with many parallel beams must be overcome to extract the full advantages for extended samples while minimizing beam attenuation. Here, that challenge is overcome by creating a lens array using cutting‐edge laser printing technology and applying it to perform scanning with MBP with up to 12 beams and at photon energies of 13 and 20 keV. This exceeds the measurement limits of conventional hard X‐ray ptychography without compromising image quality for various samples: Siemens star test pattern, Ni/Al2O3 catalyst, microchip, and gold nano‐crystal clusters.

Summary: Fish cells, such as grass carp (Ctenopharyngodon idella) kidney (CIK) cells, are harder to transfect than mammalian cells. There is a need for an efficient gene delivery system for fish cells. Here, we used CIK cell line as a model to develop a strategy to enhance RNA and plasmid DNA transfection efficiency using a nanocarrier generated from α-lactalbumin (α-NC). α-NC absorbed nucleic acid cargo efficiently and exhibited low cytotoxicity. Plasmid transfection was more efficient with α-NC than with liposomal transfection reagents. We used α-NC to co-transfect Tol2 transposase mRNA and a plasmid containing Cas9 and GFP, generating a stable transgenic CIK cell line. Genome and RNA sequencing revealed that the Cas9 and GFP fragments were successfully inserted into the genome of CIK cells and efficiently transcribed. In this study, we established an efficient transfection system for fish cells using α-NC, simplifying the process of generating stable transgenic fish cell lines.

BackgroundThe highly pathogenic avian influenza H5N1 viruses and the low pathogenic H9N2 viruses are enzootic in Egyptian poultry. Several cases of human infection with H5N1 were reported in Egypt. We previously determined that the seroprevalence of H5N1 antibodies in Egyptians exposed to poultry is 2.1% (15/708), suggesting that mild or subclinical infections with this virus occur. We aim to measure the incidence of avian influenza infection in Egyptians exposed to poultry, study risk factors of infection, study the resulting immune response, study household transmission rates, and characterize the viruses causing infections. ObjectiveThe objective of the study is to design a 7-year, prospective, household-based cohort investigation to determine incidence and household transmission of avian influenza viruses in humans exposed to poultry. MethodsAt baseline, we will collect sera to measure antibodies against influenza A. Field nurses will visit enrolled subjects at least weekly to check for influenza-like illness symptoms and verify influenza infection by a point of care rapid test. From subjects with influenza infection and their household contacts, we will collect nasal swabs, throat swabs, and nasal washes to characterize the antigenic and genetic makeup of influenza viruses infecting humans. The nurse will also obtain 2x 3-ml blood samples, one for serology, and another for isolating peripheral blood mononuclear cells. ResultsResults from this cohort will enhance our understanding of the transmission of avian influenza viruses to humans in a country where such viruses are enzootic. ConclusionsThis may enhance public health efforts aimed at reducing this burden.

ObjectiveTo investigate the current status of microbial contamination in domestic freezers and evaluate the microbial improvement effects of professional refrigerator cleaning.MethodsSamples were collected aseptically from the food dividers， vegetable frames， and door seals of 15 household refrigerators before and after cleaning in Chengdu City. A total of 90 samples were obtained. The total number of bacteria， fungi， and coliforms in the samples was determined to reflect the sanitary conditions of the refrigerator. Coliform bacteria， Staphylococcus aureus， Salmonella， Listeria monocytogenes and Yersinia enterocolitica were isolated and cultured to determine the contamination status of these pathogenic bacteria. The effect of refrigerator cleaning was analyzed comprehensively according to microorganism detection and clearance rates before and after cleaning.ResultsBefore cleaning， the total number of bacteria in the refrigerator ranged from 2.4×103 to 1.4×105 CFU/cm2. After cleaning， the total number of bacteria ranged from 0 to 230 CFU/cm2. The bacterial clearance rates of the food dividers， vegetable frames， and door seals were 99.90%， 99.89%， and 99.81%， respectively. Before cleaning， the total number of fungi in the refrigerator ranged from 0 to 750 CFU/cm2. After cleaning， the total number of fungi in the refrigerator ranged from 0 to 58 CFU/cm2. The fungal clearance rates for the partition， vegetable frame， and door seal were 99.40%， 96.99%， and 99.41%， respectively. Before cleaning， the average detection rates of coliform bacteria， Staphylococcus aureus and Salmonella， were 64.44%， 13.33%， and 2.22%， respectively； Listeria monocytogenes and Yersinia enterocolitica were not detected. After washing， the average coliform bacteria detection rate was 13.33%； Staphylococcus aureus， Salmonella， Listeria monocytogenes， and Yersinia enterocolitica were not detected.ConclusionThis study revealed the presence of a high number of bacteria and fungi in the freezers of domestic refrigerators before cleaning， with S. aureus and Salmonella contamination. After professional cleaning， their sterility significantly improved， notably reducing potential food safety risks.

Cisplatin (CDDP) is a widely used chemotherapeutic agent that has remarkable antineoplastic effects. However, CDDP can cause severe acute kidney injury (AKI), which limits its clinical application. Agrimol B is the main active ingredient found in Agrimonia pilosa Ledeb and has a variety of pharmacological activities. The effect of agrimol B on CDDP-induced renal toxicity has not been determined. To investigate whether agrimol B has a protective effect against CDDP-induced AKI, we first identify Sirtuin 1 (Sirt1) as a critical target protein of agrimol B in regulating AKI through network pharmacology analysis. Subsequently, the AKI mouse model is induced by administering a single dose of CDDP via intraperitoneal injection. By detecting the serum urea nitrogen and creatinine levels, as well as the histopathological changes, we confirm that agrimol B effectively reduces CDDP-induced AKI. In addition, treatment with agrimol B counteracts the increase in renal malondialdehyde level and the decrease in superoxide dismutase (SOD), catalase and glutathione levels induced by CDDP. Moreover, western blot results reveal that agrimol B upregulates the expressions of Sirt1, SOD2, nuclear factor erythroid2-related factor 2, and downstream molecules, including heme oxygenase 1 and NAD(P)H quinone dehydrogenase 1. However, administration of the Sirt1 inhibitor EX527 abolishes the effects of agrimol B. Finally, we establish a tumor-bearing mouse model and find that agrimol B has a synergistic antitumor effect with CDDP. Overall, agrimol B attenuates CDDP-induced AKI by activating the Sirt1/Nrf2 signaling pathway to counteract oxidative stress, suggesting that this compound is a potential therapeutic agent for the treatment of CDDP-induced AKI.

Abstract Background Lung cancer is a malignant tumor with the highest mortality worldwide. Abnormalities in the ubiquitin proteasome system are considered to be contributed to lung cancer progression with deleterious effects. DDB1 and CUL4 associated factor 13 (DCAF13) is a substrate receptor of the E3 ubiquitin ligase CRL4, but its role in lung cancer remains unknown. In this study, we aimed to investigate the regulatory mechanisms of DCAF13 in lung adenocarcinoma (LUAD). Methods So as to investigate the effect of DCAF13 on lung adenocarcinoma cell function using in vivo and in vitro. Mechanistically, we have identified the downstream targets of DCAF13 by using RNA-sequencing, as well as ubiquitination assays, co-immunoprecipitation, immunofluorescence, immunohistochemistry and chromatin immunoprecipitation - qPCR experiments. Results Our findings reveal that DCAF13 is a carcinogenic factor in LUAD, as it is highly expressed and negatively correlated with clinical outcomes in LUAD patients. Through RNA-sequencing, it has been shown that DCAF13 negatively regulates the p53 signaling pathway and inhibits p53 downstream targets including p21, BAX, FAS, and PIDD1. We also demonstrate that DCAF13 can bind to p53 protein, leading to K48-linked ubiquitination and degradation of p53. Functionally, we have shown that DCAF13 knockdown inhibits cell proliferation and migration. Our results highlight the significant role of DCAF13 in promoting LUAD progression by inhibiting p53 protein stabilization and the p53 signaling pathway. Furthermore, our findings suggest that high DCAF13 expression is a poor prognostic indicator in LUAD, and DCAF13 may be a potential therapeutic target for treating with this aggressive cancer. Conclusions The DCAF13 as a novel negative regulator of p53 to promote LUAD progression via facilitating p53 ubiquitination and degradation, suggesting that DCAF13 might be a novel biomarker and therapeutical target for LUAD.

The breeding of flax and industrial hemp in China began in the 1950s. After the end of the 20th century, the development of related breeding technologies has been accelerating. The current main breeding techniques include cross breeding, mutagenesis, distant hybridization, utilization of male sterile flax, haploid breeding, hybrid breeding, tissue culture, transgene, gene editing, molecular marker assisted selection, and other technologies. Despite many new breeding techniques, cross breeding still are the main breeding method for flax and industrial hemp now. This paper introduced the production status, breeding history, germplasm collection, standard formulation, breeding methods, and new varieties of flax and industrial hemp. Analyzed some problems in flax and industrial hemp breeding, and put forward some suggestions.

The current advanced neural network models are expanding in size and complexity to achieve improved detection accuracy. This study designs a lightweight fabric defect detection algorithm based on YOLOv7-tiny, called YOLOv7-tiny-MGCK. Its objectives are to improve the performance of fabric defect detection against complex backgrounds and to find a balance between the algorithm’s lightweight nature and its accuracy. The algorithm utilizes the Mish activation function, known for its superior nonlinear performance capability and smoother curve, enabling the neural network to manage more complex challenges. The Ghost convolution module is also incorporated to reduce computation and model parameters. The lightweight upsampling technique CARAFE facilitates the flexible extraction of deep features, coupled with their integration with shallow features. In addition, an improved K-Means clustering algorithm, KMMP, is employed to select appropriate anchor box for fabric defects. The experimental results show: a reduction in the number of parameters by 45.5% and computational volume by 41.0%, along with increases in precision by 3.9%, recall by 7.0%, and mAP by 3.0%. These results indicated that the improved algorithm achieves a more effective balance between detection performance and the requirement for a lightweight solution.

Gender inequality and bias persists in academia worldwide despite remarkable progress in recent decades. This issue is underexplored in the context of Chinese academia. Drawing on 40 semi-structured interviews with male and female academics at a Chinese research university, this paper assesses the extent and manifestations of gender inequality, bias, and discrimination in the Chinese academic profession. The findings show that most of the male academics had gender-blind perspectives and believed that Chinese academia has an egalitarian structure that is fairer to women than other sectors of activity, and allows them to attain career success. Concurrently, some were suspicious of female academics' success and explained it based on sexual innuendo. Nonetheless, a considerable number of male academics felt privileged compared to women, explaining this privilege in terms of social and biological factors. The female academics mostly perceived no overt discrimination in academia but described subtle discrimination and biases in which gender could shape opportunities and career advancement. Our findings highlight differences in the perceptions of male and female academics, the prevalence of male power in academia, and micropolitical practices that (re)produce gender inequality.

The composition and content of fatty acids (FAs) and amino acids (AAs) are important nutritional and sensory traits in aquaculture fish. To meet increasing demand while retaining quality, genetic selection in breeding programs is urgently needed to improve these traits. In this study, we performed the genome-wide association study (GWAS) to identify genetic variants and candidate genes potentially linked to FA and AA compositions in grass carp muscle. We focused on key dietary components, including unsaturated FAs and essential AAs. Through profiling of total FA and AA contents, we identified strong positive correlations among the compositions of most FAs and AAs. From our GWAS panel, 4,913,199 high-quality single nucleotide polymorphisms (SNPs) were identified across the genome, of which 32 SNPs linked to 18 candidate genes were significantly associated with FA levels, and 202 SNPs linked to 115 candidate genes associated with AA contents. In addition, we categorized our sequencing population by region and detected allele frequencies of SNPs across four geographic locations. Notably, four FA-associated SNPs and 28 AA-associated SNPs exhibited geographic specificity. These results offered valuable insights into the complex genetic basis of FA and AA metabolism and deposition. Furthermore, this work provides potential genetic markers for selective breeding aimed at enhancing flesh quality in the economically important fish species, grass carp.

Transport-energy transitions pose complex challenges that have been extensively studied in high-income countries in response to national mandates for climate action. Low- and middle-income countries, however, have low but rapidly growing motorisation rates and face very different challenges in adopting new technologies to foster economic development and ensure equitable access to clean transportation. Here, we present a set of narrative scenarios for the future of the Kenyan transport-energy system co-developed through engagement with 41 local experts and decision-makers. Through the co-development of a Kenyan transport-energy system model, we present a decision-support tool, populated with those scenarios, to assist policymakers at regional, national and international levels in building policy and investment pipelines to support low-carbon economic growth. We find that Kenya’s transport-energy system can meet both development and climate goals, but this demands strong policy support for efficient public transport and targeted support for road vehicle electrification. Increased support for non-motorised transport is essential to provide equitable access to services and economic opportunities. Favourable pathways result in significant e-mobility uptake, which is anticipated to increase electricity demand by 5%–56% from 2023 to 2040, relative to the IEA Kenya Energy Outlook’s Stated Policies scenario, representing a 2.7–3.9x increase in Kenya’s total electricity demand over the same period. From a macro-fiscal perspective, results show that e-mobility has two important consequences for Kenya. Firstly, under high e-mobility scenarios, there is a negative fiscal impact that taxation revenues from the sale of transport fuels reduce by up to 41% relative to the low e-mobility scenario (though, notably, they still increase marginally from the 2023 level because of increasing transport demand). Secondly, high e-mobility scenarios have a positive impact on balance of payments by reducing the fuel import bill by up to 69% relative to the low e-mobility baseline. This corresponds to a reduction in foreign exchange requirement of up to $4.2bn annually by 2050.