Timing effect of high temperature exposure on the plasticity of internode and plant architecture in maize

The occurrence of high temperature(HT)in crop production is becoming more frequent and unpredictable with global warming,severely threatening food security.The state of an organ’s growth and development is largely determined by the temperature conditions it is exposed to over time.Maize is the main cereal crop,and its stem growth and plant architecture are closely related to lodging resistance,and especially sensitive to temperature.However,systematic research on the timing effect of HT on the sequentially developing internode and stem is currently lacking.To identify the timing effect of HT on the morphology and plasticity of the stem in maize,two hybrids(Zhengdan 958(ZD958),Xianyu 335(XY335))characterized by distinct morphological traits in the stem were exposed to a 7-day HT treatment from the V6 to V17 stages(Vn presents the vegetative stage with n leaves fully expanded)in 2019-2020.The results demonstrated that exposure to HT during V6-V12 accelerated the rapid elongation of stems.For instance,HT occurring at V7 and V12 specifically promoted the lengths and weights of the 3rd-5th and 9th-11th internodes,respectively.Meanwhile,HT slowed the growth of internodes adjacent to the promoted internodes.Interestingly,compared with control,the plant height was significantly increased soon after HT treatment,but the promotion effect became narrower at the subsequent flowering stage,demonstrating a self-adjusting mechanism in the maize plant in response to HT.Importantly,HT altered the plant architectures,including a rising of the ear position and increase in the ear position coefficient.XY335 exhibited greater sensitivity in stem development than ZD958 under HT treatment.These findings improve our systematic understanding of the plasticity of internode and plant architecture in response to the timing of HT exposure.

L1/2 -Regularized Quantile Method for Sparse Phase Retrieval

The sparse phase retrieval aims to recover the sparse signal from quadratic measurements. However, the measurements are often affected by outliers and asymmetric distribution noise. This paper introduces a novel method that combines the quantile regression and the L1/2-regularizer. It is a non-convex, non-smooth, non-Lipschitz optimization problem. We propose an efficient algorithm based on the Alternating Direction Methods of Multiplier (ADMM) to solve the corresponding optimization problem. Numerous numerical experiments show that this method can recover sparse signals with fewer measurements and is robust to dense bounded noise and Laplace noise.

基于word2vec与K-means算法食品安全事件自动聚类研究

类别知识在食品安全事件的应急处理中不仅保证了相应应急措施推送的精准性而且可以提高食品安全事件应急处理的效率。为了更加精准的获取食品安全事件中的类别知识,结合统计、对比和分析的系统方法,通过食品安全事件的微博和信息数据,基于word2vec和K-means算法,文章探究了类别知识挖掘的具体流程、方法和相应的类别知识挖掘结果的评价等方面的相应问题。通过具体的实验,在所使用的数据上,确定了最优的聚类模型。

Cob color, an indicator of grain dehydration and agronomic traits in maize hybrids

Screening for agronomic traits associated with grain moisture is important for mechanical grainharvesting of maize. Cob color as a visual indicator has received limited attention, though it has been subjected to artificial selection, and may have some association with threshability. To investigate the relationships between cob color and grain moisture and other agronomic traits, field experiments were conducted during 2016–2017 using 23 commercial hybrids with red or white cobs. Kernels of red-cob hybrids dehydrated faster, showing lower moisture content at harvest than white-cob hybrids. A cob color index(CCI) was established as a quantitative measure of cob color in the hybrid panel. Ranging from0(whitest) to 17.98(reddest), CCI correlated well with grain dehydration and other agronomic traits associated with growth ontogeny, plant morphology, and plant N content. Strong selection of red cob for recently released hybrids suitable for mechanical grain-harvesting indirectly validated the observed link between cob color and grain dehydration. We propose that cob color and CCI could be used in future selection of maize cultivars bred for mechanical grain-harvesting.

A Left-Handed, Stem-Twining Plant from the Miocene Shanwang Formation of Eastern China

Twining stems of plants are very common in extant tropical and subtropical forests, and the climbing growth habit of plants may be an evolutionary innovation and ecological adaptation to either closed, shady or open, edge environments. However, the origin of handedness in climbing plants remains unclear. Here we report a Miocene (ca. 16 million years ago) macrofossil from the Shanwang Formation of Shandong Province, Eastern China, unequivocally exhibiting the first direct fossil evidence for a left-handed, stem-twining growth habit in plants. This fossil plant bears a thicker, slightly curved supporting stem (2 - 3.5 mm wide), which is loosely, spirally twined by a thinner stem (1.5 - 2 mm wide), possibly representing part of distal branches from a liana or vine.

Cardiac-Adaptive Conductive Hydrogel Patch Enabling Construction of Mechanical–Electrical Anisotropic Microenvironment for Heart Repair

The biomimetic construction of a microstructural–mechanical–electrical anisotropic microenvironment adaptive to the native cardiac tissue is essential to repair myocardial infarction(MI).Inspired by the 3D anisotropic characteristic of the natural fish swim bladder(FSB),a novel flexible,anisotropic,and conductive hydrogel was developed for tissue-specific adaptation to the anisotropic structural,conductive,and mechanical features of the native cardiac extracellular matrix.The results revealed that the originally stiff,homogeneous FSB film was tailored to a highly flexible anisotropic hydrogel,enabling its potential as a functional engineered cardiac patch(ECP).In vitro and in vivo experiments demonstrated the enhanced electrophysiological activity,maturation,elongation,and orientation of cardiomyocytes(CMs),and marked MI repair performance with reduced CM apoptosis and myocardial fibrosis,thereby promoting cell retention,myogenesis,and vascularization,as well as improving electrical integration.Our findings offer a potential strategy for functional ECP and provides a novel strategy to bionically simulate the complex cardiac repair environment.

Melatonin Augments the Effects of Fluoxetine on Depression-Like Behavior and Hippocampal BDNF–TrkB Signaling

Depression is a debilitating psychiatric disorder with a huge socioeconomic burden, and its treatment relies on antidepressants including selective serotonin reuptake inhibitors(SSRIs). Recently, the melatonergic system that is closely associated with the serotonergic system has been implicated in the pathophysiology and treatment of depression. However, it remains unknown whether combined treatment with SSRI and melatonin has synergistic antidepressant effects. In this study, we applied a sub-chronic restraint stress paradigm, and evaluated the potential antidepressant effects of combined fluoxetine and melatonin in adult male mice. Sub-chronic restraint stress(6 h/day for 10 days) induced depression-like behavior as shown by deteriorated fur state, increased latency to groom in the splash test, and increased immobility time in the forced-swim test. Repeated administration of either fluoxetine or melatonin at 10 mg/kg during stress exposure failed to prevent depression-like phenotypes. However,combined treatment with fluoxetine and melatonin at theselected dose attenuated stress-induced behavioral abnormalities. Moreover, we found that the antidepressant effects of combined treatment were associated with the normalization of brain-derived neurotrophic factor(BDNF)–tropomyosin receptor kinase B(Trk B) signaling in the hippocampus, but not in the prefrontal cortex. Our findings suggest that combined fluoxetine and melatonin treatment exerts synergistic antidepressant effects possibly by restoring hippocampal BDNF–Trk B signaling.

Unique and complementary suppression of cGAS-STING and RNA sensing- triggered innate immune responses by SARS-CoV-2 proteins

The emergence of SARS-CoV-2 has resulted in the COVID-19 pandemic,leading to millions of infections and hundreds of thousands of human deaths.The efficient replication and population spread of SARS-CoV-2 indicates an effective evasion of human innate immune responses,although the viral proteins responsible for this immune evasion are not clear.In this study,we identified SARS-CoV-2 structural proteins,accessory proteins,and the main viral protease as potent inhibitors of host innate immune responses of distinct pathways.In particular,the main viral protease was a potent inhibitor of both the RLR and cGAS-STING pathways.Viral accessory protein 0RF3a had the unique ability to inhibit STING,but not the RLR response.On the other hand,structural protein N was a unique RLR inhibitor.0RF3a bound STING in a unique fashion and blocked the nuclear accumulation of p65 to inhibit nuclear factor-KB signaling.3CL of SARS-CoV-2 inhibited K63-ubiquitin modification of STING to disrupt the assembly of the STING functional complex and downstream signaling.Diverse vertebrate STINGs,including those from humans,mice,and chickens,could be inhibited by 0RF3a and 3CL of SARS-CoV-2.The existence of more effective innate immune suppressors in pathogenic coronaviruses may allow them to replicate more efficiently in vivo.Since evasion of host innate immune responses is essential for the survival of all viruses,our study provides insights into the design of therapeutic agents against SARS-CoV-2.

Effect of dispersion on indistinguishability between single-photon wave-packets

With propagating through a dispersive medium,the temporal–spectral profile of optical pulses should be inevitably modified.Although such dispersion effect has been well studied in classical optics,its effect on a singlephoton wave-packet has not yet been entirely revealed.In this paper,we investigate the effect of dispersion on indistinguishability between single-photon wave-packets through the Hong–Ou–Mandel(HOM)interference.By dispersively manipulating two weak coherent single-photon wave-packets which are prepared by attenuating mode-locked laser pulses before interfering with each other,we observe that the difference of the second-order dispersion between two optical paths of the HOM interferometer can be mapped to the interference curve,indicating that(i)with the same amount of dispersion effect in both paths,the HOM interference curve must be only determined by the intrinsic indistinguishability between the wave-packets,i.e.,dispersion cancellation due to the indistinguishability between Feynman paths;and(ii)unbalanced dispersion effect in two paths cannot be canceled and will broaden the interference curve thus providing a way to measure the second-order dispersion coefficient.Our results suggest a more comprehensive understanding of the single-photon wave-packet and pave ways to explore further applications of the HOM interference.

Hertz-rate metropolitan quantum teleportation

Quantum teleportation can transfer an unknown quantum state between distant quantum nodes,which holds great promise in enabling large-scale quantum networks.To advance the full potential of quantum teleportation,quantum states must be faithfully transferred at a high rate over long distance.Despite recent impressive advances,a high-rate quantum teleportation system across metropolitan fiber networks is extremely desired.Here,we demonstrate a quantum teleportation system which transfers quantum states carried by independent photons at a rate of 7.1±0.4 Hz over 64-km-long fiber channel.An average single-photon fidelity of≥90.6±2.6%is achieved,which exceeds the maximum fidelity of 2/3 in classical regime.Our result marks an important milestone towards quantum networks and opens the door to exploring quantum entanglement based informatic applications for the future quantum internet.

NOTCH2NLC expanded GGC repeats in patients with cerebral small vessel disease

Objective GGC repeat expansions in the human-specific NOTCH2NLC gene have been reported as the cause of neuronal intranuclear inclusion disease(NIID).Given the clinical overlap of cognitive impairment in NIID and cerebral small vessel disease(CSVD),both diseases have white matter hyperintensity on T2-fluid attenuated inversion recovery sequences of brain MRI,and white matter hyperintensity is a primary neuroimaging marker of CSVD on MRI.Therefore,we hypothesised that the GGC repeat expansions might also contribute to CSVD.To further investigate the relationship between NOTCH2NLC GGC repeat expansions and CSVD,we performed a genetic analysis of 814 patients with the disease.Methods We performed a comprehensive GGC repeat expansion screening in NOTCH2NLC from 814 patients with sporadic CSVD.Their Fazekas score was greater than or equal to 3 points.Repeat-primed PCR and fluorescence amplicon length analyses were performed to identify GGC repeat expansions,and whole-exome sequencing was used to detect any pathogenic mutation in previously reported genes associated with CSVD.Results We identified nine(1.11%)patients with pathogenic GGC repeat expansions ranging from 41 to 98 repeats.The minor allele frequency of expanded GGC repeats in NOTCH2NLC was 0.55%.Conclusion Our findings suggest that intermediate-length and longer-length GGC repeat expansions in NOTCH2NLC are associated with sporadic CSVD.This provides new thinking for studying the pathogenesis of CSVD.

细菌降解邻苯二甲酸酯的研究进展

邻苯二甲酸酯(Phthalates esters,PAEs)是一类混合在塑料中以增强其可塑性和多功能性的有机化合物。同时,PAEs也是一种典型环境内分泌干扰物,长期生产和使用塑料制品已对环境和生物体乃至人类身体健康造成危害。研究发现微生物降解已成为削减环境中PAEs的主要途径。文中对近年来国内外在PAEs的结构及分类、毒理学效应、在环境中的污染状况、细菌降解的菌株多样性、降解途径及分子机制等方面的相关研究进行了总结与回顾,以期对解决PAEs的污染问题提供参考。

波兰近期税收改革简介及对我国的启示

本文介绍了波兰税收制度的基本情况,重点介绍了近期税收改革的一系列新举措,包括全面推行增值税标准化审计文件等强化税收征管的措施,推出以"创新盒"为代表的鼓励创新的税收优惠政策,出台吸引投资的经济特区优惠政策以及推行各项增加社会福利的税式支出政策。从进一步加强我国税收治理的角度出发,提出我国应推进减税降费激发市场活力、发挥数据效能提高治理水平以及推进税收共治提升行政效能等政策建议。