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The large hadron collider (LHC) plans a series of upgrades to enter a higher luminosity phase in which the particle experiments are going to be more efficient. However, higher luminosity will introduce a lot of out-of-interest interactions, regarded as pile-up interactions, which are going to be a great challenge to the event reconstruction. To meet the challenges of the pile-up, in toroidal LHC apparatus (ATLAS) and compact muon solenoid (CMS) of the LHC, a new particle detection technique was proposed, which combines high resolution time measurement with position information. This technique will enhance the capability in event discrimination for pile-up mitigation, to make the event reconstruction more accuracy. Under this background, a novel silicon-based semiconductor detector called low-gain avalanche detector (LGAD), was expected to satisfy the requirements on high time precision and spatial resolution of millimeter pitch size, which also has application potentials in other particle physics experiment complexities. Considering the spatial density of the LGAD channels, an application specific integrated circuit (ASIC) with high granularity, instead of discreet component electronics, is indispensable for the high time precision readout. The ASIC was expected to integrate amplification, discrimination and time-to-digital conversion (TDC), to conduct high precision time measurement with digitized output in the front-end close to the detectors. As one of the collaborators of the ATLAS, a research group in University of Science and Technology of China (USTC) has been working on the LGAD study and testing. Meanwhile, a prototype ASIC for the LGAD readout has been designed and tested in the fast electronics laboratory of USTC. The analog part (including amplifier and discriminator) and the TDC part of the ASIC were researched, designed and tested independently, which will be integrated in one ASIC later after the verification. To meet the requirement of the time precision, the TDC was expected to reach a minimum bin size smaller than 20 ps and an RMS resolution better than 10 ps. And considering the minimum interval between two hit events in one channel, the conversion time (defined as the digitizing time consumption after the arrival of stop signal) of TDC should be smaller than 20 ns. For these design indexes, a dual-ring vernier structure was proposed for coarse-fine time measurement with “locked delay difference” in the vernier line, so that the requirements of TDC bin size, measurement range and conversion time were reached. Additionally, the ring structure largely optimizes the circuit area. During the TDC design, the structure of the delay cell, phase detector (and also the TDC arbiter), DLL and its charge pump were studied and optimized for better performance. The test results indicate that the TDC successfully reaches a bin size around 15 ps and an RMS resolution better than 10 ps, which meets the design indexes well.

Objectives: The purpose of this research was to study the impact of histone acetylation on glioblastoma multiforme (GBM) and lower‐grade gliomas (LGG) and its potential implications for patient prognosis. We aimed to assess the histone acetylation score (HAs) and its relationship with key genes involved in histone acetylation regulation. Method: The TCGA‐GBMLGG dataset, which provides comprehensive genomic and clinical information, was utilized for this study. We calculated the HAs by analyzing the expression levels of histone acetylation‐related genes, including histone acetyltransferases and histone deacetylases, in GBM and LGG patients. Kaplan–Meier survival analysis was performed to evaluate the prognostic value of the HAs. Furthermore, correlation analysis and differential expression analysis were conducted to assess the relationship between the HAs and key genes involved in histone acetylation regulation, as well as the expression differences of immune checkpoint genes. Results: Our analysis revealed a significant association between the HAs and patient prognosis, with higher HAs correlating to poorer outcomes in GBM and LGG patients. We observed a positive correlation between the HAs and key genes involved in histone acetylation regulation, indicating their potential role in modulating histone acetylation levels. Moreover, we found significant expression differences for immune checkpoint genes between high and low HAs groups, suggesting a potential impact of histone acetylation on the immune response in GBM and LGG. Conclusion: This study highlights the significance of histone acetylation in GBM and LGG. The HAs demonstrated prognostic value, indicating its potential as a clinically relevant biomarker. The correlation between the HAs and key genes involved in histone acetylation regulation provides insights into the underlying mechanisms driving histone acetylation dysregulation in GBM and LGG. Furthermore, the observed expression differences of immune checkpoint genes suggest a potential link between histone acetylation and the immune response. These findings contribute to our understanding of the molecular basis of GBM and LGG and have implications for personalized treatment approaches targeting histone acetylation and the immune microenvironment. Further validation and functional studies are needed to confirm these findings and explore potential therapeutic strategies. [ABSTRACT FROM AUTHOR]

Jiangxi Province is a biodiversity hotspot in the People's Republic of China and has abundant land-snail species (247). Beta diversity is a key concept for understanding the functioning of ecosystems, the conservation of biodiversity, and the management of ecosystems. Here, the pattern of beta diversity for land snails in Jiangxi Province was analyzed. The results showed that the spatial turnover component was the main contributor to beta diversity, indicating that additional conservation efforts must target an increase in the number of protected areas, which should be spread across each one of the areas, to maximize the protection of species diversity. The nestedness component of diversity was always low, but there was a marked difference between microsnails, in which zero values occurred in 41.3% of all cases, and macrosnails, in which zero values occurred in only 2.7% of cases. There was a difference in the pattern of beta diversity between the two. The principal coordinate analysis showed a clear pattern with four groups in Jiangxi Province. In addition, we found significant effects of precipitation and altitude on overall beta diversity. These results will provide important basic information for the conservation of biodiversity in land snails. Key words: Jiangxi Province, beta diversity, biodiversity, land snails, conservation. La province du Jiangxi est un centre de biodiversite en Republique populaire de Chine qui compte de nombreuses especes d'escargots (247). La diversite beta est une notion cle pour la comprehension du fonctionnement des ecosystemes, la conservation de la biodiversite et la gestion des ecosystemes. La distribution de la diversite beta d'escargots terrestres dans la province du Jiangxi a ete analysee. Les resultats montrent que la composante de renouvellement spatial est le principal facteur expliquant la diversite beta, ce qui indique que les nouveaux efforts de conservation devraient viser une augmentation du nombre d'aires protegees, qui devraient etre reparties dans toutes les regions, pour maximiser la protection de la diversite specifique. La composante d'emboitement de la diversite est toujours faible, mais il y a une difference marquee entre les escargots microscopiques, pour lesquels une valeur de zero est observee dans 41,3% de tous les cas, et les escargots macroscopiques, pour lesquels une valeur de zero est observee dans 2,7% des cas. Une difference est observee dans le motif de diversite beta entre les deux groupes. L'analyse en coordonnees principales fait ressortir un motif clair comptant quatre groupes dans la province du Jiangxi. Nous avons en outre releve des effets significatifs des precipitations et de l'altitude sur la diversite beta globale. Ces resultats fournissent d'importants renseignements de base pour la conservation de la biodiversite des escargots terrestres. [Traduit par la Redaction] Mots-cles: province du Jiangxi, diversite beta, biodiversite, escargots terrestres, conservation., Introduction Biodiversity patterns and the mechanisms of their formation have become an important topic (Kennedy and Norman 2005; Sutherland et al. 2009). In the past, studies have focused mainly on [...]

Osteosarcoma (OS) is the most common primary bone tumor that affects adolescents and young adults. Disruption of microRNA (miRNA) regulation is well established in the pathophysiology of different cancers, including OS. Increased expression of miR-9 in OS positively correlates with the tumor size, clinical stage, and distant metastasis. In the present study, we used two different OS cell lines, MG-63 and Saos-2, as in vitro models. miR-9 inhibitor and miR-9 mimics were used to study the function of miR-9 in these two cell lines. We determined the effect of miR-9 inhibition on cell proliferation, cell cycle, apoptosis, and the protein expression of different genes. Our results demonstrated that miR-9 inhibition in the human OS cell lines suppresses their metastatic potential, as determined by decreased cell proliferation and cell cycle arrest, decreased invasion, and increased apoptosis. The Western blot analysis showed that E-cadherin, matrix metalloproteinase 13, forkhead box O3, Bcl-2-like protein 11, and β-catenin are involved in miR-9 signaling. Moreover, miR-9 mimics rescued the effects caused by the inhibition of miR-9 in the OS cell lines. Our findings suggest that miR-9 is important for mediating OS cell migration, invasion, metastasis, and apoptosis. Inhibition of miR-9 could be further explored as a therapeutic target to treat OS.

Waveform digitization at sampling rates up to several giga-samples per second is one of the approaches to achieve high-precision time measurements. In recent years, achieving high precision at lower sampling rates has emerged as a significant research topic. In this article, we focus on time measurement electronics, in which the bandpass sampling method is applied to obtain high precision at a sampling rate of roughly 100 MSps. An analog front-end circuit is designed, in which the input pulse signal is bandpass-filtered and amplified before sampling. A pipelined real-time time extraction algorithm is designed using the techniques of interpolation and cross correlation. A 1024-point fast Fourier transform algorithm is adopted to implement the cross correlation operation. Four time measurement channels are implemented in a mid-range field-programmable gate array, and the measurement rate of 116 kHz is achieved. Tests are conducted to evaluate the performance of the timing system. The typical RMS precision is better than 0.4 ps. [ABSTRACT FROM AUTHOR]

The development of perovskite light‐emitting diodes (PeLEDs) with both high efficiency and excellent stability remains challenging. Herein, a strong correlation between the lattice strain in perovskite films and the stability of resulting PeLEDs is revealed. Based on high‐efficiency PeLEDs, the device lifetime is optimized by rationally tailoring the lattice strain in perovskite films. A PeLED with a high peak external quantum efficiency of 18.2% and a long lifetime of 151 h (T70, under a current density of 20 mA cm−2) is realized with a minimized lattice strain in the perovskite film. In addition, an increase in the lattice strain is found during the long‐time device stability test, indicating that the degradation of the local perovskite lattice structure could be one of the degradation mechanisms for long‐term stable PeLEDs. [ABSTRACT FROM AUTHOR]

Manganese-based organic–inorganic metal halide composites have been considered as promising candidates for lead-free emitters. However, in spite of their excellent luminescence properties in green and red regions, blue emission—a critical component for white light generation—from pristine manganese-based composites is currently missing. In this work, we successfully achieve blue luminescence center in manganese-based composites through selecting specific organic component methylbenzylamine (MBA). Our approach is fundamentally different from green and red emission in manganese-based composites, which result from manganese-halide frameworks. The coexistence of different luminescence centers in our manganese-based composites is confirmed by photoluminescence (PL) and photoluminescence excitation (PLE) results. As a result of different photoluminescence excitation responses of different emission centers, the resulting emission color can be tuned with selecting different excitation wavelengths. Specifically, a white light emission can be obtained with Commission Internationale de l'éclairage coordinates of (0.33, 0.35) upon the 330 nm excitation. We further demonstrate the promise of our manganese-based composites in the anti-counterfeiting technology and multicolor lighting. Our results provide a novel strategy for full-spectral emission in manganese-based organic–inorganic metal halide composites and lay a solid foundation for a range of new applications. [ABSTRACT FROM AUTHOR]

This article presents the design and test results of a waveform sampling application-specific integrated circuit (ASIC) based on the switched capacitor array (SCA). It integrates eight differential-input channels, and each channel consists of a 256-cell capacitor array, 256 12-bit Wilkinson analog-to-digital converters (ADCs), and a serial data readout. A sampling rate of up to 5 Gsps is achieved with a low-jitter delay-locked loop (DLL). Two shared coarse counters running at the rising and falling edges of the reference clock are used to extend the time measurement range. Several crosstalk reduction strategies were adopted in the circuit design, especially in the clock generation circuit and the digitization circuit. The ASIC has been fabricated in 180-nm CMOS process. The test results show that the random noise is approximately 0.7-mV rms after the fixed-pattern noise correction and that the precision of waveform timing is better than 7-ps rms with the sampling interval correction. [ABSTRACT FROM AUTHOR]

The crisscross progress of transportation and energy carries the migrating track of human society development and the evolution of civilization, among which the decarbonization strategy is a key issue. Traffic carbon emissions account for 16.2% of total energy carbon emissions, while road traffic carbon emissions account for 11.8% of total energy carbon emissions. Therefore, road traffic is a vital battlefield in attaining the goal of decarbonization. Employing clean energy as an alternative fuel is of great significance to the transformation of the energy consumption structure in road transportation. Hydrogen and ammonia are renewable energy with the characteristics of being widely distributed and clean. Both exist naturally in nature, and the products of complete combustion are substances (water and nitrogen) that do not pollute the atmosphere. Because it can promote agricultural production, ammonia has a long history in human society. Both have the potential to replace traditional fossil fuel energy. An overview of the advantages of hydrogen and ammonia, as well as their development in different countries such as the United States, the European Union, Japan, and other major development regions is presented in this paper. Related research topics of hydrogen and ammonia's production, storage and transferring technology have also been analyzed and collated to stimulate the energy production chain for road transportation. The current cost of green hydrogen is between $2.70–$8.80 globally, which is expected to approach $2–$6 by 2030. Furthermore, the technical development of hydrogen and ammonia as a fuel for engines and fuel cells in road transportation is compared in detail, and the tests, practical applications and commercial popularization of these technologies are summarized, respectively. Opportunities and challenges coexist in the era of the renewable energy. Based on the characteristics and development track of hydrogen and ammonia, the joint development of these two types of energy is meant to be imperative. The collaborative development mode of hydrogen and ammonia, together with the obstacles to their development of them are both compared and discussed. Finally, referring to the efforts and experiences of different countries in promoting hydrogen and ammonia in road transportation, corresponding constructive suggestions have been put forward for reference. At the end of the paper, a framework diagram of hydrogen and ammonia industry chains is provided, and the mutual promotion development relationship of the two energy sources is systematically summarized. [ABSTRACT FROM AUTHOR]

Incorporating chiral organic compounds into metal halide frames is a common and useful method to introduce chirality in metal halide composites. The structures of resulting racemic and chiral composites are usually considered to be nearly identical owing to similar chemical bonding. In this work, by incorporating chiral MBABr (bromide methylbenzylamine) into an inorganic frame, a significant crystallization difference between the resulting racemic and chiral metal halide composites is observed, as confirmed by both structural and spectroscopic measurements. In addition, the structural transformation in the chiral composites can also be induced by moisture, ascribed to the asymmetric hydrogen bonding in chiral materials. These results provide new insights for the future synthesis of chiral materials and open up new possibilities to advance the materials functionalities. [ABSTRACT FROM AUTHOR]

Background: Arthroscopic techniques have gradually become popular for anterior talofibular ligament (ATFL) repair. However, the reliability of the repair and the risk of nerve injuries are of concern. The aim of this study was to evaluate the fully intra-articular lasso-loop stitch technique for arthroscopic ATFL repair. Methods: From October 2018 to December 2019, 43 cases with chronic lateral ankle instability were treated with this fully intra-articular lasso-loop stitch technique using the Arthro-Pierce instrument. The Karlsson-Peterson score, Cumberland Ankle Instability Tool (CAIT) score, visual analog scale (VAS) score, anterior drawer and talar tilt stress fluoroscopy were evaluated at the preoperative and final follow-up appointments, respectively. All surgical complications were also recorded. Results: A total of 39 cases were followed up for a mean of 28.23 ± 3.64 months (range, 23-34 months). At the final follow-up, the averages of the Karlsson-Peterson, CAIT and VAS scores were 90.26 ± 6.58, 88.56 ± 7.21 and 0.79 ± 1.06, respectively. During surgery, 2 cases were modified with augmentation of the inferior extensor retinaculum. No nerve injuries were encountered. Only 1 female complained about mild knot irritation. A 25-year-old solider required revision surgery due to an accidental injury. Conclusion: We found the fully intra-articular lasso-loop stitch technique for ATFL repair using the Arthro-Pierce instrument to be reliable and safe with a sufficient and good-quality ligament remnant. Level of Evidence: Level IV, retrospective case series. [ABSTRACT FROM AUTHOR]

Orientational manipulation of transition dipole moment (TDM) plays an important role in controlling the polarization of excited states in light emission as well as lasing actions. The present work discovers vertically aligned TDMs in hybrid perovskite films through angle‐resolved photoluminescence (PL) measurements, which show enhanced emission through the film edge. With increasing excitation intensity, the edge emission induced by these vertically aligned TDMs becomes dominant and eventually leads to amplified spontaneous emission (ASE) through the edge view. Meanwhile, polarized emission of both PL and electroluminescence (EL) provides further evidence for vertically aligned TDMs. Surprisingly, the degree of polarization (DOP) through the film edge is increased when grain boundary defects are passivated through either stochiometric engineering or self‐passivation by mobile ions under working conditions. With increasing DOP, ASE threshold of the perovskite film is reduced owing to enhanced collective behaviors of light‐emitting states. This work presents a useful method to manipulate TDMs in organic–inorganic hybrid perovskites. [ABSTRACT FROM AUTHOR]

Shanghai high repetition rate X-ray-free electron laser (XFEL) and extreme light facility (SHINE) has been under construction. It aims at producing X-ray pulses in a photon energy range from 0.4 to 25 keV. To achieve the design goal, SHINE requires precise distribution and synchronization of the clock and timing signals over a long distance of approximately 3.1 km. Based on the standard White Rabbit (WR) protocol, a prototype of a high-precision clock and timing electronics is designed based on a customized clock frequency. Great attention is paid to the design of hardware and field programmable gate array (FPGA) logic to achieve high-precision clock synchronization, fine phase adjustment, and frequency tuning, as well as flexible shaping of timing signals. Test results indicate that the skew jitter of the clock signal is better than 20 ps within the frequency range from around 1 Hz to 1 MHz, and the clock phase delay can be adjusted with a step size of about 500 ps. As for the timing signals, the skew jitter is better than 40 ps rms. Moreover, the temperature drifts of the clock and timing signals are better than 3 ps/°C. [ABSTRACT FROM AUTHOR]

In the Cooling storage ring External-target Experiment (CEE) in heavy ion research facility in Lanzhou (HIRFL), multigap resistive plate chambers (MRPCs) detectors are used for high-precision time-of-flight (TOF) measurement to identify the scattered particles after the ion beam hits the target. Regarding the external TOF (eTOF) and 2/3 internal TOF (iTOF) detectors, a ~25-ps rms time precision is required for the readout electronics, whereas for the other 1/3 iTOF detectors, a ~10-ps rms precision is required. A readout electronics prototype was designed, including the front-end electronics (FEE) based on analog signal amplification, discrimination, and the time-to-digital module (TDM), based on field-programmable gate array (FPGA) time-to-digital converter (TDC), to achieve high-precision time measurement. PreAmplifier-DIscriminator (PADI) is used in the design of the FEE, while an FPGA TDC, based on tapped delay line (TDL) structure, with a time precision performance better than 5-ps rms, is implemented in the TDM, as well as the trigger matching circuit and other control logic. The performance of the whole system was tested under different input signal charges and the results indicated that the time precision is better than 10-ps rms, which satisfies the application requirements. [ABSTRACT FROM AUTHOR]

With the capability to manipulate the built‐in field in solar cells, ferroelectricity is found to be a promising attribute for harvesting solar energy in solar cell devices by influencing associated device parameters. Researchers have devoted themselves to the exploration of ferroelectric materials that simultaneously possess strong light absorption and good electric transport properties for a long time. Here, it is presented a novel and facile approach of combining state‐of‐art light absorption and electric transport properties with ferroelectricity by the incorporation of room temperature 1D ferroelectric perovskite with 3D organic–inorganic hybrid perovskite (OIHP). The 1D/3D mixed OIHP films are found to exhibit evident ferroelectric properties. It is notable that the poling of the 1D/3D mixed ferroelectric OIHP solar cell can increase the average Voc can be increased from 1.13 to 1.16 V, the average PCE from 20.7% to 21.5%. A maximum power conversion efficiency of 22.7%, along with an enhanced fill factor of over 80% and open‐circuit voltage of 1.19 V, can be achieved in the champion device. The enhancement is by virtue of reduced surface recombination by ferroelectricity‐induced modification of the built‐in field. The maximum power point tracking measurement substantiates the retention of ferroelectric‐polarization during the continued operation. [ABSTRACT FROM AUTHOR]

Understanding the feasibility to couple semiconducting and magnetic properties in metal halide perovskites through interface design opens new opportunities for creating the next generation spin‐related optoelectronics. In this work, a fundamentally new phenomenon of optically induced magnetization achieved by coupling photoexcited orbital magnetic dipoles with magnetic spins at perovskite/ferromagnetic interface is discovered. The depth‐sensitive polarized neutron reflectometry combined with in situ photoexcitation setup, constitutes key evidence of this novel effect. It is demonstrated that a circularly polarized photoexcitation induces a stable magnetization signal within the depth up to 7.5 nm into the surface of high‐quality perovskite (MAPbBr3) film underneath a ferromagnetic cobalt layer at room temperature. In contrast, a linearly polarized light does not induce any detectable magnetization in the MAPbBr3. The observation reveals that photoexcited orbital magnetic dipoles at the surface of perovskite are coupled with the spins of the ferromagnetic atoms at the interface, leading to an optically induced magnetization within the perovskite's surface. The finding demonstrates that perovskite semiconductor can be bridged with magnetism through optically controllable method at room temperature in this heterojunction design. This provides the new concept of utilizing spin and orbital degrees of freedom in new‐generation spin‐related optoelectronic devices. [ABSTRACT FROM AUTHOR]