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Although the so-called magnetic geometrical factor, Bl, of a Kibble balance does not appear in the Kibble equations, it offers the precision link between electrical and mechanical quantities and furthers a quasiquantum traceability path for mass metrology. This feature makes the magnet system, supplying the Bl in Kibble equations, play a core role in Kibble balances. Following the open-hardware idea, we report here on the design, manufacture, assembly, optimization, and finally performance of a compact magnet system for the Tsinghua tabletop Kibble balance. Notably, the magnet system showcased in this study facilitates a straightforward upper levitation of splitting through a streamlined mechanism guide, substantially enhancing the ease of open and close operations. Experimental tests show the realized magnet systems can yield a high Bl value (e.g., 400 Tm for a bifilar coil and 800 Tm for a single coil with a wire gauge of 0.2 mm) meanwhile a low volume/weight (40 kg), thanks to the uniformity improvement of magnetic profiles. Furthermore, important parameters related to systematic effects, such as the current effect, are checked, aiming for a final mass-realization accuracy at the $10^{-8}$ level.

The southern spread of rice agriculture is of great academic interest. Although it already has a broad chronological framework, newly introduced rice use and its impact on local subsistence and ecological systems are still unclear. In this study, we explore these issues by analysing phytoliths recovered from continuous sediments of Cave No. 4 at the Nanshan site in Fujian Province, together with evidence from surrounding sites. The results show that rice was introduced into southeast China at 7,500 cal. yr BP, but the dominance of the hunting-gathering system was not challenged until later, between 5,000 and 3,500 cal. yr BP, when cultivation of rice, together with foxtail and broomcorn millets, was widely practiced in the region. This suggests that mixed farming in Southeast China, likely originating around the middle Yangtze River, became widespread and gradually systematic during the previous two-millennium adoption. This rice-millet mixed agricultural system changed the former hunting-gathering subsistence system, promoting the agriculturalization process, cultural prosperity and population growth, thus providing a solid basis for rice expansion and cultural migration to Southeast Asia.

Real-time quantitative analysis of tetracyclines is urgently needed to provide consumers with early warning of potential risks. Herein, we report a dual-mode green emissive fluorescent probe, which refers to the liquid mode and the solid mode of electrospun films doped with nitride-doped carbon nanosheets (NCNSs) for real-time detection of doxycycline (DOX). Highly fluorescent NCNSs were prepared by low-temperature solid treatment of urea and sodium citrate. With the addition of DOX, the green emission intensity of NCNSs at 475 nm can be obviously reduced. Method validation exhibited a good linear relationship in 0.05–150 μM between the fluorescence quenching of NCNSs and the concentration of DOX with a limit of detection (LOD) of 0.0127 μM. Furthermore, the immobilization of NCNSs in PAN carriers forming electrospun films stabilizes the green fluorescence of NCNSs. Additionally, electrospun films integrated into a smartphone were developed for real-time detection of DOX with LOD of 0.285 μM. Additionally, DOX in milk was monitored with satisfactory recoveries. Therefore, the integration of the smartphone and electrospun film provides a promising and convenient method for real-time identification of DOX in food analysis.

The Kibble balance is a precision instrument for realizing the mass unit, the kilogram, in the new international system of units (SI). In recent years, an important trend for Kibble balance experiments is to go tabletop, in which the instrument’s size is notably reduced while retaining a measurement accuracy of $10^{-8}$ . In this article, we report a new design of a tabletop Kibble balance to be built at Tsinghua University. The Tsinghua Kibble balance aims to deliver a compact instrument for robust mass calibrations from 10 g to 1 kg with a targeted measurement accuracy of $50 \mu \text{g}$ or less. Some major features of the Tsinghua Kibble balance system, including the design of a new magnet, one-mode measurement scheme, the spring-compensated magnet moving mechanism, and magnetic shielding considerations, are discussed.

•The archaeobotanical findings indicated that Guye people have heavily relied on arboreal foodstuffs in south China, 5900–5400 BP.•The subsistence system presents a schedule centred on summer and autumn, according to the fruiting seasonality of recovered plant remains.•Well-scheduled subsistence and affluent resources in South China may delay the adoption process of exotic cereal cultivation.

Due to the bidirectional power transmission, high power density, and high efficiency, bidirectional CLLC resonant converters are attracting more and more research attention in electric vehicles and energy storage systems. However, the existing models are difficult to unify the bidirectional circuits to analyze and design the circuit factors, and thus the parameter design approach and bidirectional synchronous rectification (SR) become rather complex and cumbersome. Especially in asymmetric parameter design, a lot of calculations or iterations are needed, which seriously increase the difficulty of design. To address this concern, a bidirectional unified modeling, analysis, and design method is proposed in this article. By selecting appropriate and quantitative bidirectional circuit factors, this model unifies the forward and reverse circuits and establishes the relationship between them, which greatly simplifies the calculation or iteration of the parameter design and the complexity of bidirectional SR. In addition, this parameter design method makes the bidirectional gain reach a higher range and reduces the range of bidirectional switching frequency. Finally, this unified modeling, analysis, and design method is verified in bidirectional CLLC resonant converters including symmetrical full-bridge, asymmetrical full-bridge, symmetrical half-bridge, and asymmetrical half-bridge CLLC, respectively.

Although carbon nitride (g-C3N4) is a common photoconversion material, its photocatalytic activity is constrained by fast carrier recombination and weak light absorption. Here, a precursor reforming strategy is developed to construct melamine precursor rods with an etched surface. After being calcinated, the morphology of the melamine precursor is transformed to interconnected vesicles with open characteristics. In addition, XPS analysis and DFT calculations demonstrate the formation of oxygen-containing groups in the open vesicles, thereby boosting charge separation for surface photocatalytic H2production. Such a synergistic regulation strategy produces superior visible-light photocatalytic activity (608.3 μmol h−1g−1), and the H2production rate is 4.43-times higher than that of bulk g-C3N4. These findings suggest an accessible way to construct effective photocatalysts viaa precursor reforming strategy that can efficiently boost carrier production and spatial separation.

Three-dimensional (3D) photocatalysts can overcome the serious aggregation exhibited by two-dimensional (2D) nanosheets caused by unavoidable van der Waals forces. However, the water splitting efficiency needs further improvement, which can be achieved by boosting the exciton dissociation and charge transfer. Herein, a gelatin-confined strategy is developed to construct 3D tube-assembled g-C3N4open frameworks. The gelatin plays multiple roles in the thermal polymerization. It not only engineers the grain growth of g-C3N4, but also supplies in situexternal C and O sources. Experimental and density functional theory (DFT) calculation results indicate that the self-integration effects of the unique 3D architecture and bridging electron delocalization channels lead to prompt exciton production and dissociation, and subsequent carrier transfer. Consequently, the g-C3N4open framework achieves a hydrogen evolution rate of 99.4 μmol h−1and an apparent quantum efficiency of 7.43% at 450 nm, significantly superior to previously reported C and (or) O-doped 2D g-C3N4and other 3D g-C3N4materials. These findings provide promising guidance for designing efficient 3D architectures to drive photocatalysis and support the broader application of cost-effective biopolymers.

Safety management of the process industry plays a significant role in protecting life and property. Fault diagnosis techniques have been widely utilized for safety management of the process industry. However, an acceptable fault diagnosis accuracy is difficult to achieve due to the large scale and the high integration of modern industrial processes. To deal with this issue, in this paper a novel class-specific distributed monitoring weighted naı̈ve Bayes (CDMWNB) method is proposed to improve the fault diagnosis performance of complex processes. In the proposed CDMWNB method, first, the whole process should be divided into subblocks by decomposition; second, dynamic independent component analysis (DICA) is used to obtain the I2statistic and the control limits (CLs) in each subblock; and finally, the proposed CDMWNB method can be developed for fault diagnosis. To prove the effectiveness of the proposed CDMWNB method, case studies of fault diagnosis using the Tennessee Eastman (TE) benchmark process are carried out. The effectiveness and feasibility of the proposed CDMWNB method are proven by simulation results.

Despite tremendous improvements in the photovoltaic performance of perovskite solar cells through diverse strategies, there is still a significant gap in terms of consistency and efficiency with respect to conventional structures. The widely accepted methods for passivating perovskite imperfections as well as the controlled growth of perovskite grains continue to create challenges for further improving the performance of devices for practical application. In this work, we designed and developed multifunctional oxyl-terminated melem nanoparticles (OMN) modifiers (containing C-N, CO, and -OH passivation functional groups) which we incorporated in the perovskite via anti-solvent engineering. The large surface area of OMN ensured that high-quality perovskite films were produced by modulating the crystallization process and thoroughly passivating numerous defects via the anti-solvent. Unlike the charge-transport limiting effect of conventional carbon nitride (CN) nanosheets, our nanoparticles enhanced the photovoltaic performance of the PSCs. The power conversion efficiency (PCE) of the inverted MAPbI3-based device with OMN demonstrates a notable improvement in power conversion efficiency (PCE), achieving a value of 19.31% compared to the 16.75% for the pristine device. The PCE of triple-cation perovskite device also increased, rising from 19.58% to 22.65%. Furthermore, the stability of the devices was improved by the combination of high-quality perovskite films and exceptional defect passivation.

High power conversion efficiency (PCE) and long-term stability are inevitable issues faced in practical device applications of perovskite solar cells. In this paper, significant enhancements in the device efficiency and stability are achieved by using a surface-active lead acetate (Pb(OAc)2) at the top or bottom of CH3NH3PbI3(MAPbI3)-based perovskite. When a saturated Pb(OAc)2solution is introduced on the top of the MAPbI3perovskite precursor, the OAc–in Pb(OAc)2participates in lattice restructuring of MAPbI3to form MAPbI3–x(OAc)x, thereby producing a high-quality perovskite film with high crystallinity, large grain sizes, and uniform and pinhole-free morphology. Moreover, when Pb(OAc)2solution is mixed in the poly(3,4-ethylenedioxythiophene)–poly(styrenesulfonate) (PEDOT–PSS) solution in the bottom way, the OAc–in Pb(OAc)2improves the water resistance of PEDOT–PSS. As the OAc–easily bonds with the Pb2+, the deposition of MAPbI3precursor onto the Pb(OAc)2mixed with PEDOT–PSS results in a reduction of the uncoordinated Pb, leading to strong stabilization of the perovskite layer. Both the top- and bottom-treated devices exhibit enhanced PCE values of 18.93% and 18.28%, respectively, compared to the conventional device with a PCE of 16.47%, which originates from decreased trap sites and reduced energy barriers. In particular, the bottom-treated device exhibits long-term stability, with more than 84% of its initial PCE over 800 h in an ambient environment.

Field investigations have revealed the ability of the climbing perch Anabas testudineusto survive in highly contaminated water bodies. The aryl hydrocarbon receptor (AhR) pathway is vital in mediating the toxicity of aromatic hydrocarbon contaminants, and genotypic variation in the AhR can confer resistance to these contaminants. Thus, we characterized the AhR pathway in A. testudineusin order to understand the mechanism(s) underlying the resistance of this species to contaminants and to broaden current knowledge on teleost AhR. In A. testudineus, four AhRs, two AhR nuclear translocators (ARNTs), and one AhR repressor (AhRR) were found. Transient transfection assays revealed that AhR1a, AhR1b, and AhR2b were functional, whereas AhR2a was poorly activated by the potent agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Two ARNTs (partner of AhR) and one AhRR (repressor of AhR) all were functional with each of the active AhR. As a major form, the insensitivity of AhR2a might serve as a potential mechanism for A. testudineus’ reduced sensitivity to severe contamination. We explored the key residues that may account for AhR2a’s insensitivity in silico and then functionally validated them in vitro. Two sites (VCS322–324, M370) in its ligand-binding domain (LBD) were proved critical for its sensitivity to TCDD. This systematic exploration of the AhR pathway showed that most members have maintained their traditional functions as expected, whereas a nonfunctionalization event has occurred for AhR2a.

ABSTRACTA key step in pre-mRNA splicing is the recognition of 3ʹ splicing sites by the U2AF large and small subunits, a process regulated by numerous trans-acting splicing factors. How these trans-acting factors interact with U2AF in vivois unclear. From a screen for suppressors of the temperature-sensitive (ts) lethality of the C. elegansU2AF large subunit gene uaf-1(n4588)mutants, we identified mutations in the RNA binding motif gene rbm-5, a homolog of the tumor suppressor gene RBM5. rbm-5mutations can suppress uaf-1(n4588)ts-lethality by loss of function and neuronal expression of rbm-5was sufficient to rescue the suppression. Transcriptome analyses indicate that uaf-1(n4588)affected the expression of numerous genes and rbm-5mutations can partially reverse the abnormal gene expression to levels similar to that of wild type. Though rbm-5mutations did not obviously affect alternative splicing per se, they can suppress or enhance, in a gene-specific manner, the altered splicing of genes in uaf-1(n4588)mutants. Specifically, the recognition of a weak 3ʹ splice site was more susceptible to the effect of rbm-5. Our findings provide novel in vivoevidence that RBM-5 can modulate UAF-1-dependent RNA splicing and suggest that RBM5 might interact with U2AF large subunit to affect tumor formation.

Perovskite optoelectronic devices are being regarded as future candidates for next-generation optoelectronic devices. Device performance has been shown to be influenced by the perovskite film, which is determined by the grain size, surface roughness, and film coverage; therefore, developing controllable and highly crystalline perovskite films is pivotal for highly efficient devices. In this work, an innovative bulk heterojunction (BHJ)-assisted grain growth (BAGG) technique was developed to accurately control the quality of perovskite films. By a simple modulation of the polymer-to-PC61BM ratio in the BHJ film, the transition to a complete film phase from the perovskite precursor was accurately regulated, resulting in a controllable perovskite grain growth and high-quality final perovskite film. Moreover, because the BHJ layer could seep deeply into the perovskite active layer through the grain boundaries in the BAGG process, it facilitated the interface engineering and charge transport. The perovskite solar cells containing an optimized CH3NH3PbI3film presented a high efficiency of 18.38% and fill factor of 83.71%. The perovskite light-emitting diode that contained a nanoscale and uniform CH3NH3PbBr3film with full coverage presented enhanced emission properties with a brightness value of 1600 cd/m2at 6.0 V and a luminous efficiency of 0.56 cd/A.

Pediatric patients with a neurogenic urinary bladder, caused by developmental abnormalities including spina bifida, exhibit chronic urological problems. Surgical management in the form of enterocystoplasty is used to enlarge the bladder, but is associated with significant clinical complications. Thus, alternative methods to enterocystoplasty have been explored through the incorporation of stem cells with tissue engineering strategies. Within the context of this review, we will examine the use of bone marrow stem cells and induced pluripotent stem cells (iPSCs), as they relate to bladder regeneration at the anatomic and molecular levels. The use of bone marrow stem cells has demonstrated significant advances in bladder tissue regeneration as multiple aspects of bladder tissue have been recapitulated including the urothelium, bladder smooth muscle, vasculature, and peripheral nerves. iPSCs, on the other hand, have been well characterized and used in multiple tissue-regenerative settings, yet iPSC research is still in its infancy with regards to bladder tissue regeneration with recent studies describing the differentiation of iPSCs to the bladder urothelium. Finally, we examine the role of the Sonic Hedgehog signaling cascade that mediates the proliferative response during regeneration between bladder smooth muscle and urothelium. Taken together, this review provides a current, comprehensive perspective on bladder regeneration.

The fundamental mechanism of grain growth evolution in the fabrication process from the precursor phase to the perovskite phase is not fully understood despite its importance in achieving high-quality grains in organic–inorganic hybrid perovskites, which are strongly affected by processing parameters. In this work, we investigate the fundamental conversion mechanism from the precursor phase of perovskite to the complete perovskite phase and how the intermediate phase promotes growth of the perovskite grains during the fabrication process. By monitoring the morphological evolution of the perovskite during the film fabrication process, we observed a clear rod-shaped intermediate phase in the highly crystalline perovskite and investigated the role of the nanorod intermediate phase on the growth of the grains of the perovskite film. Furthermore, on the basis of these findings, we developed a simple and effective method to tailor grain properties including the crystallinity, size, and number of grain boundaries, and then utilized the film with the tailored grains to develop perovskite solar cells.

•Xianrendong and Diaotonghuan sites (30,000–12,000 cal Y BP) are well-known for the earliest pottery and the earliest cultivated rice micro-remains in the world.•Meta-analysis of the usage traces and plant micro-remain analysis were used in this study.•Multiple functions of perforated shells tools were revealed, such as, harvesting grasses, processing acorns and digging up and scraping tubers and roots.

Centromeres are known to cluster around nucleoli in drosophila and mammalian cells, but the significance of the nucleoli-centromere interaction remains underexplored. To determine if the interaction is dynamic under different physiological and pathological conditions, we examined nucleolar structure and centromeres at various differentiation stages using cell culture models and the results showed dynamic changes in nucleolar characteristics and nucleoli-centromere interactions through differentiation and in cancer cells. Embryonic stem cells usually have a single large nucleolus, which is clustered with a high percentage of centromeres. As cells differentiate into intermediate states, nucleolar number increases and the centromere association decreases. In terminally differentiated cells, including myotubes, neurons and keratinocytes, the number of nucleoli and their association with centromeres are at the lowest. Cancer cells demonstrate the pattern of nucleoli number and nucleoli-centromere association that is akin to proliferative cell types, suggesting that nucleolar reorganization and changes in nucleoli-centromere interactions may play a role in facilitating malignant transformation. This idea is supported in a case of pediatric rhabdomyosarcoma, in which induced differentiation reduces nucleolar number and centromere association. These findings suggest active roles of nucleolar structure in centromere function and genome organization critical for cellular function in both normal development and cancer.

Immunosenescence is described as a decline in the normal functioning of the immune system associated with physiologic ageing. Immunosenescence contributes to reduced efficacy to vaccination and increased susceptibility to infectious diseases in the elderly. Extensive studies of laboratory animal models of ageing or donor lymphocyte analysis have identified changes in immunity caused by the ageing process. Most of these studies have identified phenotypic and functional changes in innate and adaptive immunity. However, it is unclear which of these defects are critical for impaired immune defense against infection. This review describes the changes that occur in innate and adaptive immunity with ageing and some age-related viral diseases where defects in a key component of immunity contribute to the high mortality rate in mouse models of ageing.

Dopamine (DA) neurons in the ventral tier of the substantia nigra pars compacta (SNc) degenerate prominently in Parkinson’s disease, while those in the dorsal tier are relatively spared. Defining the molecular, functional, and developmental characteristics of each SNc tier is crucial to understand their distinct susceptibility. We demonstrate that Sox6expression distinguishes ventrally and dorsally biased DA neuron populations in the SNc. The Sox6+population in the ventral SNc includes an Aldh1a1+subset and is enriched in gene pathways that underpin vulnerability. Sox6+neurons project to the dorsal striatum and show activity correlated with acceleration. Sox6−neurons project to the medial, ventral, and caudal striatum and respond to rewards. Moreover, we show that this adult division is encoded early in development. Overall, our work demonstrates a dual origin of the SNc that results in DA neuron cohorts with distinct molecular profiles, projections, and functions.