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Background Long-term smoking is a risk factor for chronic pain, and chronic nicotine exposure induces pain-like effects in rodents. The anterior cingulate cortex (ACC) has been demonstrated to be associated with pain and substance abuse. This study aims to investigate whether ACC microglia are altered in response to chronic nicotine exposure and their interaction with ACC neurons and subsequent nicotine-induced allodynia in mice. Methods We utilized a mouse model that was fed nicotine water for 28 days. Brain slices of the ACC were collected for morphological analysis to evaluate the impacts of chronic nicotine on microglia. In vivo calcium imaging and whole-cell patch clamp were used to record the excitability of ACC glutamatergic neurons. Results Compared to the vehicle control, the branch endpoints and the length of ACC microglial processes decreased in nicotine-treated mice, coinciding with the hyperactivity of glutamatergic neurons in the ACC. Inhibition of ACC glutamatergic neurons alleviated nicotine-induced allodynia and reduced microglial activation. On the other hand, reactive microglia sustain ACC neuronal excitability in response to chronic nicotine, and pharmacological inhibition of microglia by minocycline or liposome-clodronate reduces nicotine-induced allodynia. The neuron-microglia interaction in chronic nicotine-induced allodynia is mediated by increased expression of neuronal CX3CL1, which activates microglia by acting on CX3CR1 receptors on microglial cells. Conclusion Together, these findings underlie a critical role of ACC microglia in the maintenance of ACC neuronal hyperactivity and resulting nociceptive hypersensitivity in chronic nicotine-treated mice.

Dual-functional metal oxide semiconductors that can detect the values of two different physical quantities, such as light intensity and gas concentration, have been the subject of many studies because they are used in the Internet of Things (IoT). However, the opposite sensing mechanisms for photons and gas molecules pose challenges for material design. In this study, we developed a dual-functional sensor that uses hybrid amorphous ZnSnO (a-ZTO)/graphene nanosheet (GNS) composite films. GNSs were incorporated into a-ZTO films so that the recombination process for photo-generated electron/hole pairs was suppressed owing to the favorable band alignment at the ZTO/GNS interface. The a-ZTO/GNS dual-functional sensor had a responsivity of 26.39 A/W at 350 nm and exhibited a fast response speed, with a rise time of 0.71 s and a decay time of 0.95 s. ZTO/GNS nanocomposite film also featured a smaller cluster size so that more electrons were produced for the chemical reaction of gas. Under UV illumination of 10 mW/cm2, the dual-functional sensor exhibited a gas response of 12.8, against a 5-ppm concentration of ozone gas. These results demonstrate that this dual-functional device can serve as not only a high-performance UV photodetector but also a highly sensitive gas sensor.

Mechanically ventilated patients suffering critical illness are at high risk of developing neurocognitive impairments. Angiotensin type 2 receptor (AGTR2) has been demonstrated to be anti-inflammatory and neuroprotective. The present study thus aimed to investigate whether AGTR2 can alleviate cerebral dysfunction in mice subjected to cochallenge with lipopolysaccharide (LPS) and mechanical ventilation (MV), and to reveal the underlying mechanism. We utilized a mice model that received a single injection of LPS (1 mg/kg, intraperitoneally) followed 2 h later by MV (10 ml/kg, lasting for 2 h). Pretreatment with the AGTR2 pharmacological agonist C21 (0.03, 0.3, and 3 mg/kg, intraperitoneally, once daily, lasting for 10 days). Locomotor activity and behavioral deficits were evaluated 24 h post-MV by open-field and fear-condition tests. Brain hippocampus and prefrontal cortex tissues were collected for immunofluorescence staining and western blotting to evaluate the resulting impacts on microglia, including morphological traits, functional markers, synaptic engulfment, superoxide production, and signaling molecules. Compared with vehicle-control, pre-administrated C21 reduced the branch endpoints and length of microglia processes in a dose-dependent manner in mice subjected to LPS/MV. The neuroprotective effect of AGTR2 was behaviorally confirmed by the improvement of memory decline in LPS/MV-treated mice following C21 pretreatment. In addition to morphological alterations, C21 reduced microglial functional markers and reduced microglial-dendrite contact and microglial engulfment of synaptic protein markers. In terms of the underlying molecular mechanism, AGTR2 stimulation by C21 leads to activation of protein phosphatase 2A, which subsequently mitigates microglial PKCδ and NF-κB activation, and inhibites NOX2-derived ROS production. The AGTR2 agonist C21 alleviates behavioral deficits in those mice subjected to LPS/MV, via mechanisms that involve reactive microglia and abnormal synaptic plasticity in NOX2-derived ROS and the PKCδ-NFκB pathway.

Energy internet zones, which supply and manage multiple energy kinds to customers simultaneously, attract more and more attentions for its high energy efficiency. This paper discussed the optimal weekly bidding strategy for a energy internet zone in midterm timescale. The optimal amount of bilateral contract and selling prices of multiple energy kinds can be obtained for expected profit maximization. Stochastic optimization is adopted to manage the uncertainties of electricity market prices and load demands. A energy internet zone in shanghai, China is adopted to illustrate the proposed model. The result shows that the energy internet zones prefer to supply the base load by signing bilateral contracts. The signed contracts increase with the decrease of contract prices and local photovoltaic system’s installed capacity.

Background Grape hyacinth (Muscari spp.) is one of the most important ornamental bulbous plants. However, its lengthy juvenile period and time-consuming transformation approaches under the available protocols impedes the functional characterisation of its genes in flower tissues. In vitro flower organogenesis has long been used to hasten the breeding cycle of plants but has not been exploited for shortening the period of gene transformation and characterisation in flowers. Results A petal regeneration system was established for stable transformation and function identification of colour gene in grape hyacinth. By culturing on Murashige and Skoog medium (MS) with 0.45 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 8.88 μM 6-benzyladenine (6-BA), during the colour-changing period, the flower bud explants gave rise to regeneration petals in less than 3 months, instead of the 3 years required in field-grown plants. By combining this system with Agrobacterium-mediated transformation, a glucuronidase reporter gene (GUS) was delivered into grape hyacinth petals. Ultimately, 214 transgenic petals were regenerated from 24 resistant explants. PCR and GUS quantitative analyses confirmed that these putative transgenic petals have stably overexpressed GUS genes. Furthermore, an RNAi vector of the anthocyanidin 3-O-glucosyltransferase gene (MaGT) was integrated into grape hyacinth petals using the same strategy. Compared with the non-transgenic controls, reduced expression of the MaGT occurred in all transgenic petals, which caused pigmentation loss by repressing anthocyanin accumulation. Conclusion The Agrobacterium transformation method via petal organogenesis of grape hyacinth took only 3–4 months to implement, and was faster and easier to perform than other gene-overexpressing or -silencing techniques that are currently available.

The underwater images suffer from low contrast, low visibility and color deviation which caused by scattering and absorption. In this paper, the method based on color-line model and homomorphic filtering is proposed to enhance the underwater image. First of all, the homomorphic filtering is used to remove the color deviation in the underwater image and the obtained image will be used for subsequent processes. Then, the transmission of the underwater image is estimated through the solution of the offsets that the color lines along the background-light vector from the origin. We develop a non-convex optimization function to obtain the transmission of the underwater image. Finally, the color correction is added in the underwater image which obtained by the color-line method. The simulation experiments results show that the proposed method is superior to the current state-of-the-art methods in the four aspects of quantitative analysis, qualitative analysis, color accuracy analysis, and restoring synthesized underwater images.

Safety concerns, caused by complex and unpredictable adulterants, run through the entire industrial chain of traditional Chinese medicines (TCMs). However, the conventional circulation traceability system only focuses on a certain end or link at the back end of the TCM industrial chain, ignoring the integrity of the links cross the entire industrial chain and lacking traceability. In consequence, a strict and rational supervision system is urgently required for the entire industrial chain.We hypothesize that DNA barcoding would be a suitable measure for the traceability of adulterants in the entire TCM industrial chain.In this study, Rhei Radix et Rhizoma was selected as a model to establish a traceability system for the entire TCM industrial chain. A total of 110 samples, including leaves, seeds, roots, decoction pieces, and traditional Chinese patent medicines (TCPMs), were collected upstream, midstream, and downstream of the entire industrial chain of Rhei Radix et Rhizoma. The ndhF-rpl32 fragment rather than the universal DNA barcodes, which could not distinguish the three original species of Rhei Radix et Rhizoma, was selected as a specific DNA barcode to evaluate the practical application of DNA barcoding in the chain.The results showed that the ndhF-rpl32 fragment in all samples could be amplified and bi-directionally sequenced. Based on the standard operating procedures of DNA barcoding, the ndhF-rpl32 fragment clearly distinguished the seven Rheum species collected upstream of the entire industrial chain. For the samples collected midstream and downstream of the entire industrial chain, 25% of the 36 commercial decoction pieces samples were identified as adulterants, whereas the eight TCPM samples were all derived from genuine Rhei Radix et Rhizoma.This study shows that DNA barcoding is a powerful and suitable technology that can be applied to trace TCMs in the entire industrial chain, thereby assuring clinical medication safety.

Seeing that the light in the water is affected by absorption and scattering, underwater image will suffer degradation including low contrast, low visibility and color deviation. Therefore, the key issue of underwater image enhancement is to improve the visibility and the contrast of underwater images. In this paper, we proposed an underwater image dehazing algorithm combining three main steps of homomorphic filtering, double transmission map and dual-image wavelet fusion. First at all, we removed the color deviation in the underwater image by homomorphic filtering. Then, we obtained the enhanced image by depth map which calculate the difference between the light and dark channels. Finally, the dual-image wavelet fusion technique is used to combine the enhanced image obtained by the depth map with the enhanced image obtained by the dark channel. In addition, we obtained the contrast enhanced image which use Contrast-Limited Adaptive Histogram Equalization (CLAHE) method. Through simulation experiments, the proposed method has better visual effects and better effect on entropy, average gradient and underwater color image quality evaluation (UCIQE) compared with other popular methods.

The high sensitivity of droplet digital PCR (ddPCR) contributes to its excellent performance in animal and microorganism identification, but the utilization of ddPCR is limited in plant adulterant identification of highly processed products for which effective methods are lacking.This study investigated the feasibility of ddPCR in the identification of plant adulterants in Chinese patent medicine (CPM) as groundwork to develop ddPCR assays for other highly processed goods.The original plant, processed and highly processed products of Mutong (Akebiae Caulis) and its two adulterants were used to analyze the specificity, sensitivity, and practical performance of the developed singleplex and triplex ddPCR assays.The results revealed that the limit of detection (LOD) and limit of quantification (LOQ) for the selective ddPCR assays developed to identify Mutong and its adulterants were 0.00002 ng/μl and 0.00016 ng/μl, respectively, and that the regression equations representing the relationships between DNA concentration and target copy number all exhibited good linearity. Furthermore, the common adulterant of Mutong in three samples of Longdan Xiegan pills was successfully identified through ddPCR assays and confirmed by Sanger sequencing.This work comprehensively revealed the great ability of ddPCR technology in detecting plant adulterants in traditional Chinese medicine (TCM), providing a method for the quality control of highly processed plant products with complex components for commonly used goods.

Environmental antibiotic resistance genes (ARGs) are a type of emerging pollutant that has been widely concerning. However, investigations into the contamination of ARGs in mining areas have been scarce. Here, the types, abundances, and influencing factors of ARGs and mobile genetic elements (MGEs) were investigated in soil/sediment of the Dexing copper mine area in June 2019 by using high-throughput quantitative polymerase chain reaction (HT-qPCR). Furthermore, the influence of heavy metals and MGEs factors on ARGs was studied using the multivariate statistical analysis method. The results showed that there were a variety of ARGs in the Dexing copper mining area, and the maximum detected number of ARGs was 70. At the relative abundance level, the relative abundance of individual sites reached 0.085. In the Dexing copper mine, multidrug, MLSB

Since synthetic pigments are potentially harmful to human health, natural ones such as bixin, one of the carotenoids, are favored. As the second widely used natural pigment in the world, there is significant interest in the biosynthetic pathway of bixin which has not been fully elucidated. This review summarizes the chemical properties, extraction methods, biosynthetic pathway and application of bixin. In addition, we compared the difference between traditional extraction methods and new extraction techniques. Moreover, we described the genes involved in the biosynthetic pathway of bixin and the effects of abiotic stress on the biosynthesis of bixin, and discussed the application of bixin in food, pharmaceutical and chemical industries. However, the researches on bixin biosynthesis pathway are mostly carried out at the transcriptome level and most of the gene functions have not been elucidated. Therefore, we propose to characterize the entire bixin biosynthetic pathway using techniques of genomics, bioinformatics, and phytochemistry. This will help facilitate the synthetic biology research of bixin and development of bixin into new drugs.由于合成色素对人类健康具有潜在危害，天然色素逐渐受到青睐。胭脂素作为类胡萝卜素物质是世界第二大天然色素，其生物合成途径是国际研究热点，目前尚未被完整解析。文中综述了胭脂素的化学特性与提取方法、合成途径研究及应用现状，比较传统提取方法与新提取技术的特点，阐述胭脂素合成通路相关基因及非生物胁迫对合成通路的影响，介绍胭脂素在食品、医药、化工产业应用现状。由于胭脂素合成通路的研究多停留在转录组水平，大多数基因功能未进行验证，文中提出综合应用基因组学、生物信息学、植物化学等学科技术进行深入研究以解析完整的胭脂素合成途径，为胭脂素合成生物学研究及新药研发奠定基础，促进胭脂素的资源开发及可持续发展。.

Understanding how ecological processes mediate community stability as a response to variation in the environment is a central goal in ecology. Four biotic mechanisms – portfolio, selection, insurance, and over-yielding effects – have been suggested to control community stability. While the significance of each of these mechanisms is debated, few studies have elucidated changes in their relative importance along environmental gradients. We used six years of field observations from a natural assembled wetland plant community to explore how stability changed directly or indirectly along an elevation gradient. All four mechanisms mentioned above contributed significantly to the variation in temporal stability (totally 94%), with selection and insurance effects being most important. Generalized multilevel path modelling indicates that the four mechanisms destabilize individual populations and functional groups, even though they have significant stabilizing effects on community productivity. The modelling also suggests that community dominance rather than species diversity largely mediate the indirect effects of elevation on community stability. Increasing elevation indirectly affects stability through changes in community dominance, synchrony, and abundance. Although no significant responses of species diversity were found along elevation gradients, species diversity apparently controlled stability both directly and indirectly through changes in community dominance, synchrony, and abundance. Our study illustrates that understanding the multivariate chains linking the direct, indirect, and interactive effects of elevation gradients on plant communities may help clarifying complex biotic stability mechanisms.

Underwater images suffer from haze, color distortion, and low contrast due to the absorption and scattering of transmitted light. A systematic approach including accurate background light (BL) estimation and transmission (TM) estimation is proposed based on color-line model for underwater images restoration. The estimation of BL candidate region is improved by combining quadtree subdivision and minimum unary gray entropy evaluation, to realize a high-quality restoration and improve accuracy of TM estimation with color-line model. Given incomplete intersection of color lines with BL, a convex optimization function is proposed to improve accuracy of TM estimation. On the basis of restorations with BL and TM estimations, pixel distribution stretching and Unsharp Masking are employed to correct color and enhance edge information for better performance of vision. Comprehensive evaluations illustrate that the proposed method could efficiently restore underwater images with visibility improvement, natural color correction, and contrast enhancement.

Distant species producing the same secondary metabolites is an interesting and common phenomenon in nature. A classic example of this is scutellarein whose derivatives have been used clinically for more than 30 years. Scutellarein occurs in significant amounts in species of two different orders, Scutellaria baicalensis and Erigeron breviscapus, which diverged more than 100 million years ago. Here, according to the genome-wide selection and functional identification of 39 CYP450 genes from various angiosperms, we confirmed that only seven Scutellaria-specific CYP82D genes and one Erigeron CYP706X gene could perform the catalytic activity of flavone 6-hydroxylase (F6H), suggesting that the convergent evolution of scutellarein production in these two distant species was caused by two independently evolved CYP450 families. We also identified seven Scutellaria-specific CYP82D genes encoding flavone 8-hydroxylase (F8H). The evolutionary patterns of CYP82 and CYP706 families via kingdom-wide comparative genomics highlighted the evolutionary diversity of CYP82D and the specificity of CYP706X in angiosperms. Multi-collinearity and phylogenetic analysis of CYP82D in Scutellaria confirmed that the function of F6H evolved from F8H. Furthermore, the SbaiCYP82D1

Tripterygiumwilfordii Hook F (TwHF) is one of the most commonly used and effective traditional Chinese herbal medicines against rheumatoid arthritis (RA). Both Tripterygium Glycoside Tablets (TGT) and Tripterygium wilfordii Tablets (TWT) are the representative TwHF-based agents enrolled into the 2019 edition of Medicine Catalog for National Basic Medical Insurance, Injury Insurance, and Maternity Insurance. However, individual differences in TGT/TWT response across patients usually exist in the process of treating RA, implying that the clinical application of the two agents may not be standardized leading to the ineffective treatment and the risk of side effects. Growing evidence show that the bioactive constituents of TwHF may often have toxicity, the package insert of TGT and TWT may not be described in detail, and the therapeutic windows of the two agents are narrow. Thus, it is an urgent task to develop a standardized clinical practice guideline for TGT and TWT in the treatment of RA. In the current study, a group of clinical experts of traditional Chinese medicine and Western medicine in the research field of rheumatism diseases, pharmacists, and methodologists of evidence-based medicine were invited to select the clinical questions, to determine the levels of the evidence and the strength of the recommendations, and to develop the recommendations and good practice points. The guideline is formed based on the combination of clinical research evidence and expert experience (evidence-based, consensus, supplemented by experience). The clinical problems which are supported by clinical evidence may form recommendations, and the clinical problems without clinical evidence may form experts’ suggestions. Both recommendations and experts' suggestions in this guideline summarized the clinical indications, usage, dosage, combined medication, and safety of TGT and TWT against RA systematically and comprehensively, which may offer a professional guidance in the context of the clinical application of the two TwHF-based agents.

Pre-trained language models such as BERT have shown remarkable effectiveness in various natural language processing tasks. However, these models usually contain millions of parameters, which prevents them from practical deployment on resource-constrained devices. Knowledge distillation, Weight pruning, and Quantization are known to be the main directions in model compression. However, compact models obtained through knowledge distillation may suffer from significant accuracy drop even for a relatively small compression ratio. On the other hand, there are only a few quantization attempts that are specifically designed for natural language processing tasks. They suffer from a small compression ratio or a large error rate since manual setting on hyper-parameters is required and fine-grained subgroup-wise quantization is not supported. In this paper, we proposed an automatic mixed-precision quantization framework designed for BERT that can simultaneously conduct quantization and pruning in a subgroup-wise level. Specifically, our proposed method leverages Differentiable Neural Architecture Search to assign scale and precision for parameters in each sub-group automatically, and at the same time pruning out redundant groups of parameters. Extensive evaluations on BERT downstream tasks reveal that our proposed method outperforms baselines by providing the same performance with much smaller model size. We also show the feasibility of obtaining the extremely light-weight model by combining our solution with orthogonal methods such as DistilBERT.

Billions of text analysis requests containing private emails, personal text messages, and sensitive online reviews, are processed by recurrent neural networks (RNNs) deployed on public clouds every day. Although prior secure networks combine homomorphic encryption (HE) and garbled circuit (GC) to preserve users' privacy, naively adopting the HE and GC hybrid technique to implement RNNs suffers from long inference latency due to slow activation functions. In this paper, we present a HE and GC hybrid gated recurrent unit (GRU) network, CryptoGRU, for low-latency secure inferences. CryptoGRU replaces computationally expensive GC-based $tanh$ with fast GC-based $ReLU$, and then quantizes $sigmoid$ and $ReLU$ with a smaller bit length to accelerate activations in a GRU. We evaluate CryptoGRU with multiple GRU models trained on 4 public datasets. Experimental results show CryptoGRU achieves top-notch accuracy and improves the secure inference latency by up to $138\times$ over one of state-of-the-art secure networks on the Penn Treebank dataset.

The growth and reproduction of plants are highly size-dependent and markedly affected by light intensity. Vallisneria spinulosa S.Z.Yan is a common submersed macrophyte and is widely used in current lake restoration projects. The size of plants to be used to get optimal restoration results is not known, however, and may vary with water clarity. In this study, the effects of different plant sizes (large, medium and small, i.e. approximately 2.40 g, 1.01 g and 0.27 g per plant) on the growth and reproduction of V. spinulosa were tested under three light intensities (high, medium, low, i.e. 25%, 6% and 1% of full sunlight, respectively). Both plant size and light intensity were found to be of great significance for plant growth and reproduction. The relative growth rate (RGR) of biomass was higher for small than for large plants at both high and low light, while the absolute growth rate (AGR) of biomass was higher for large-sized plants at medium and high light intensity. Asexual reproduction of V. spinulosa was positively correlated with plant size and more affected by plant size than by light intensity, while sexual reproduction was most affected by light intensity. RGR and AGR of plant height were highest for medium-sized plants at moderate light intensity. Therefore, the size of submersed macrophytes should be considered when using this species in connection with lake restoration. Verification of our results under field conditions is needed, though, before firm conclusions can be reached about the optimal plant size of V. spinulosa to be used in lake restoration as also other factors like, e.g. periphyton shading and wave actions may play a role.

Tripterygium wilfordii Hook F (TwHF) is one of the most commonly used and effective traditional Chinese herbal medicines against rheumatoid arthritis (RA). Both Tripterygium Glycoside Tablets (TGT) and Tripterygium wilfordii Tablets (TWT) are the representative TwHF-based agents enrolled into the 2019 edition of Medicine Catalog for National Basic Medical Insurance, Injury Insurance, and Maternity Insurance. However, individual differences in TGT/TWT response across patients usually exist in the process of treating RA, implying that the clinical application of the two agents may not be standardized leading to the ineffective treatment and the risk of side effects. Growing evidence show that the bioactive constituents of TwHF may often have toxicity, the package insert of TGT and TWT may not be described in detail, and the therapeutic windows of the two agents are narrow. Thus, it is an urgent task to develop a standardized clinical practice guideline for TGT and TWT in the treatment of RA. In the current study, a group of clinical experts of traditional Chinese medicine and Western medicine in the research field of rheumatism diseases, pharmacists, and methodologists of evidence-based medicine were invited to select the clinical questions, to determine the levels of the evidence and the strength of the recommendations, and to develop the recommendations and good practice points. The guideline is formed based on the combination of clinical research evidence and expert experience (evidence-based, consensus, supplemented by experience). The clinical problems which are supported by clinical evidence may form recommendations, and the clinical problems without clinical evidence may form experts’ suggestions. Both recommendations and experts' suggestions in this guideline summarized the clinical indications, usage, dosage, combined medication, and safety of TGT and TWT against RA systematically and comprehensively, which may offer a professional guidance in the context of the clinical application of the two TwHF-based agents.

As an important indicator for measuring the quality of business environment of different countries, ease of doing business (EDB) issued by the World Bank (WB) provides an important reference for investors in making decisions on transnational investment. The calculation method for EDB issued by the WB is improved using a technique for order preference by similarity to an ideal solution (TOPSIS) method based on Mahalanobis distance. Based on various indicator data in 2019, business environments in 121 countries participating in “the Belt and Road Initiative (BRI)” were empirically analysed and compared through such models. The result showed that TOPSIS method based on Mahalanobis distance can more fully utilise information and take the effect of negative ideal points into account. Therefore, compared with ranking method by the WB, TOPSIS method based on Mahalanobis distance is more applicable for ranking BRI countries. The ranking results indicated significant geographical characteristics. The EDB rankings obtained through the WB overestimate the business environments of countries in Central and Eastern Europe while underestimate those in Southeast Asia, Africa, etc. First published online 22 September 2020

Nanopore genome sequencing is the key to enabling personalized medicine, global food security, and virus surveillance. The state-of-the-art base-callers adopt deep neural networks (DNNs) to translate electrical signals generated by nanopore sequencers to digital DNA symbols. A DNN-based base-caller consumes $44.5\%$ of total execution time of a nanopore sequencing pipeline. However, it is difficult to quantize a base-caller and build a power-efficient processing-in-memory (PIM) to run the quantized base-caller. In this paper, we propose a novel algorithm/architecture co-designed PIM, Helix, to power-efficiently and accurately accelerate nanopore base-calling. From algorithm perspective, we present systematic error aware training to minimize the number of systematic errors in a quantized base-caller. From architecture perspective, we propose a low-power SOT-MRAM-based ADC array to process analog-to-digital conversion operations and improve power efficiency of prior DNN PIMs. Moreover, we revised a traditional NVM-based dot-product engine to accelerate CTC decoding operations, and create a SOT-MRAM binary comparator array to process read voting. Compared to state-of-the-art PIMs, Helix improves base-calling throughput by $6\times$, throughput per Watt by $11.9\times$ and per $mm^2$ by $7.5\times$ without degrading base-calling accuracy., 12 pages, 26 figures, The 29th International Conference on Parallel Architectures and Compilation Techniques (PACT'20)

The coronavirus disease 2019 (COVID-19) outbreak that occurred in late 2019 has posed a huge threat to the health of all humans, especially for individuals who already have diabetes mellitus (DM). DM is one of the most serious diseases that affect human health, with high morbidity and rates of complications. Medical scientists worldwide have been working to control blood sugar levels and the complications associated with sugar level alterations, with an aim to reduce the adverse consequences of acute and chronic complications caused by DM. Patients with DM face great challenges during the pandemic owing to not only changes in the allocation of medical resources but also their abnormal autoimmune status, which reduces their resistance to infections. This increases the difficulty in treatment and the risk of mortality. This review presents, from an epidemiological viewpoint, information on the susceptibility of patients with DM to COVID-19 and the related treatment plans and strategies used in this population.

Background: Hypoxic brain injury is one of the major causes of neurodevelopmental impairment and cardiovascular disability. LncRNA SNHG1 works as a critical factor in hypoxic induced injury, however, the potential mechanism is still not known well.Methods: The expression level of small nucleolar RNA host gene 1 (SNHG1) and miR-140-5p was detected by qRT-PCR. The western blot assay was performed to measure the level of Bcl-XL and apoptosis-related proteins. The target relationship between lncRNA SNHG1 and miR-140-5p, as well as miR-140-5p and Bcl-XL was detected by dual luciferase reporter gene assay. Cell apoptosis was assessed using Annexin V/PI staining by flow cytometry. Cell viability was analyzed by MTT assay.Results: Oxygen glucose deprivation (OGD) treatment inhibited SNHG1 and Bcl-XL expression and enhanced miR-140-5p expression. OGD treatment-induced cell viability inhibition, cell apoptosis promotion were partially abrogated when SH-SY5Y cells were transfected with pcDNA3.1-SNHG1 or miR-140-5p inhibitor. Moreover, luciferase reporter assay revealed that lncRNA SNHG1 bound directly to miR-140-5p, and miR-140-5p directly targeted Bcl-XL. The protective effect of SNHG1 overexpressing on cell apoptosis induced by OGD was attenuated after transfected with miR-140-5p mimic or sh-Bcl-XL in SH-SY5Y cells.Conclusion: LncRNA SNHG1-modulated miR-140-5p inhibition regulates Bcl-XL expression, thereby reducing cell apoptosis and recovering cell viability of SH-SY5Y cells. The results in this study provide novel insight into the mechanism of SNHG1 mediated signaling pathway during hypoxic brain injury.

A scalp-recording electroencephalography (EEG)-based brain-computer interface (BCI) system can greatly improve the quality of life for people who suffer from motor disabilities. Deep neural networks consisting of multiple convolutional, LSTM and fully-connected layers are created to decode EEG signals to maximize the human intention recognition accuracy. However, prior FPGA, ASIC, ReRAM and photonic accelerators cannot maintain sufficient battery lifetime when processing real-time intention recognition. In this paper, we propose an ultra-low-power photonic accelerator, MindReading, for human intention recognition by only low bit-width addition and shift operations. Compared to prior neural network accelerators, to maintain the real-time processing throughput, MindReading reduces the power consumption by 62.7\% and improves the throughput per Watt by 168\%., Comment: 6 pages, 8 figures

Nanopore sequencing is one of the most promising genome sequencing technologies because of its ability to produce ultra long reads and provide portability. Basecalling, the most time-consuming step in the whole flow of Nanopore genome sequencing, translates analog signals to digital DNA symbols. The state-of-the-art basecaller relies on a complex neural network consisting of convolutional, long short-term memory and fully-connected layers, and a CTC decoder. Existing neural network portable accelerators achieve low basecalling throughput per Watt when processing such neural network inferences. In this paper, we propose BRAWL, a portable B asecalling-in-memory architecture, to translate RAW electrical signa L s to digital DNA symbols in SOT-MRAMs for Nanopore portable sequencers. Compared to state-of-the-art accelerators, BRAWL improves basecalling throughput per Watt by $3.88\times$ .

Interspecific trait variability (e.g., functional diversity) is often correlated with community productivity and thus promotes ecosystem stability. However, we know little about how intraspecific trait variability mediated the effects of environmental gradients on population stability. We applied generalized multilevel path models to investigate multivariate causal hypotheses that environmental effects on population stability of a macrophyte species - Potamogeton maackianus - are mediated by physiological and morphological traits variability. Using a hierarchical nested design, we measured quarterly nine physiological traits, and monthly ten morphological traits from 9720 individuals at 27 plots along water depth gradients in Lake Erhai, China. Results showed that changes in water depth and light availability caused significant shifts in intraspecific trait variability, with cascading direct and indirect effects on temporal stability of P. maackianus. Water depth exerted major control over population stability, both directly and indirectly via shifts in morphological and physiological traits. Light availability affected population stability indirectly by altering morphological traits. Size traits (shoot morphology and root/shoot ratio) and metabolic traits captured the effect of water depth and light availability on population stability with a relative high accuracy. Our study provide a strong support to the hypothesis that intraspecific trait variability mediate the combined effects of variations on water depth and light conditions on the temporal stability of a dominant macrophtye species in Lake Erhai. Maintaining and enhancing trait variability within plant populations may help to buffer negative effects of anthropogenic environmental changes on population stability.

The spread of the coronavirus disease 2019 (COVID-19) had resulted in 16 million infected individuals and 640000 deaths across the world as of July 27, 2020. Unfortunately, there is still no sign that the epidemic spread is slowing down. China, as the first country suffering from the widespread outbreak of the epidemic, has effectively contained the spread of the epidemic since March, 2020. Therefore, confirmed cases of COVID-19 from January 20 to March 18, 2020 were taken as the sample set to establish the susceptible-exposed-infected-recovered (SEIR) model. The model was used to analyze changes in the numbers of individuals becoming infected, exposed (latently infected), susceptible, and recovered in the experimental groups taking different non-pharmaceutical interventions (NPIs) and in the control group not taking any NPIs, so as to evaluate effects of different NPIs. By doing so, the research expects to provide references to other countries for formulating corresponding policies. The results show that type-A NPIs for reducing daily contacts with infected and exposed cases and type-B NPIs for decreasing the probability of post-exposure infections both can delay the timing of large-scale infections of the susceptible population, timing of the number of exposed individuals to peak, and timing of peaking of the number of infected cases, as well as decrease the peak number of exposed cases. Moreover, type-B NPIs have more significant effects on susceptible and exposed populations. Type-C NPIs for improving the recovery rate of patients are able to effectively reduce the peak number of patients, greatly decrease the slope of the curve for the number of infected cases, substantially improve the recovery rate, and lower the mortality rate; however, these NPIs do not greatly delay the timing of the number of infected cases to peak. In addition to these, considering effects of different NPIs on the susceptible and exposed populations and in delaying the timing for the number of infected cases to peak, it is found that the government’s organization of medical supply related companies to resume production exerts the best effect. As for reducing the epidemic number of patients in the core epidemic area (CEA, Hubei Province), delivery and putting-into-operation of Leishenshan hospital shows the best effect, followed by dispatching of medical staff to support Wuhan, delivery and putting-into-operation of Huoshenshan hospital, and construction of mobile cabin hospitals.

SPE-UPLC-MS/MS was used to investigate the occurrence of 18 target antibiotics in the surface water of Poyang Lake over different seasons of 2014-2015. The maximum concentrations of sulfadiazine, oxytetracycline, and doxycycline were 56.2, 48.7, and 39.7 ng/L, respectively. Compared with those in the other lakes or surface waters, the surface water of Poyang Lake contained moderate or below-average levels of antibiotics. The significantly lower concentrations (P 0.01) of roxithromycin in June 2015 likely resulted from the dilution effect of water flow during the flood season. Antibiotic concentrations were higher in site P3-1 than in other sites (P 0.01), whereas those in other sites (P1-1, P2-1, P5-1, P6-1, P7-1, P13-1, P16-1, P17-1, P18-1) were not significantly different (P 0.05). Given that tetracyclines and sulfonamides are common veterinary medicines, the high concentrations of oxytetracycline, doxycycline, and sulfadiazine in site P3-1 might be closely related to agricultural production in the surrounding areas. The risk assessment of the main antibiotic contaminants revealed that the majority of the risk quotients of the target antibiotics were below 0.01, thereby indicating the minimal risk of these antibiotics to organisms at three different trophic levels. Sulfadimidine and sulfadiazine were identified as the main antibiotics that contribute to ecological risk in Poyang Lake, and that the daphnid is the main model organism exposed to these risks. This study provides important data for antibiotic pollution control and environmental protection in the study area and enriches environmental monitoring data on a global scale.

Carbon (C) and nitrogen (N) metabolism are essential for the growth and maintenance of submersed macrophytes. They are affected by nutrient and light availability and seasonal changes. In this study, we investigated the changes of C/N metabolism and growth of three natural submersed macrophyte populations (i.e., each in a different site), Potamogeton maackianus, in response to water depth gradients with 0.5 m interval in a freshwater lake for four seasons. Changes were identified by measuring the biomass of the sampled macrophytes and metabolite contents of soluble carbohydrate (SC), starch, and free amino acid (FAA) in their organs. Results showed that no significant and consistent changes were found in the SC and FAA contents in leaves and stems from 1.0 m to 5.5 m water depth, as compared to previous results of controlled studies, suggesting a relative stable C/N metabolism in response to the depth gradients in studied natural populations of P. maackianus. The metabolite contents with the most variations appeared mainly because of seasonal changes. The metabolite contents of the macrophyte populations were more closely correlated with the chemical parameters than with the light parameters in water columns. No significant correlations were found between the metabolite contents with the light attenuation coefficient ($K$) and Secchi depth (SD) in water columns. The NO3-N and total phosphorus (TP) contents in water columns were positively correlated with the SC and starch contents in leaves, respectively. The NH4-N content in water columns was negatively related to the FAA content in leaves. Metabolite contents had weak correlations with depth gradients and light parameters, probably because of the physiological integration among individuals by developed stolons and the canopy-forming characteristic of this species. Our results highlighted the importance of water quality to the C/N metabolism in natural population of submersed macrophyte. (C) 2017 Elsevier B.V. All rights reserved.

Metals can react with microcystin (MC), which is released from cyanobacterial blooms through various mechanisms; these reactions may mitigate the environmental and health risks of MCs but may also cause harm to aquatic ecosystems and humans. Several studies were conducted, including laboratory tests, ecological simulations, and a field investigation of Poyang Lake. The laboratory studies showed that Fe3+, Cu2+, and Pb2+ stimulated MC photodegradation under high light intensity at the water-sediment interface, which reduced the MC accumulation in the sediment. In the laboratory studies involving the addition of metal ions to lake sediment containing adsorbed MC, MC biodegradation was inhibited by supplementing with high levels of Fe3+, Cu2+, or Pb2+. Fe3+ and Pb2+ promoted MC accumulation in the hydrophyte Eichhornia crassipes at relatively low concentrations, but this effect decreased with increasing high metal concentrations. An ecological survey in Poyang Lake during the dry season demonstrated that high Fe levels can reduce MC accumulation in the sediment, which could be the result of Fe-mediated photodegradation. The results indicate that metals involved in MC transportation and degradation may play an important role in the environmental fate of MC.

Convolutional Neural Networks (CNNs) are widely adopted in object recognition, speech processing and machine translation, due to their extremely high inference accuracy. However, it is challenging to compute massive computationally expensive convolutions of deep CNNs on traditional CPUs and GPUs. Emerging Nanophotonic technology has been employed for on-chip data communication, because of its CMOS compatibility, high bandwidth and low power consumption. In this paper, we propose a nanophotonic accelerator, HolyLight, to boost the CNN inference throughput in datacenters. Instead of an all-photonic design, HolyLight performs convolutions by photonic integrated circuits, and process the other operations in CNNs by CMOS circuits for high inference accuracy. We first build HolyLight-M by microdisk-based matrix-vector multipliers. We find analog-to-digital converters (ADCs) seriously limit its inference throughput per Watt. We further use microdisk-based adders and shifters to architect HolyLight-A without ADCs. Compared to the state-of-the-art ReRAM-based accelerator, HolyLight-A improves the CNN inference throughput per Watt by 13× with trivial accuracy degradation. Published version This work is partially supported by NAP M4082282 and SUG M4082087 from Nanyang Technological University, Singapore and NSFC 61772094, China.

Ammonium pulse attributed to runoff of urban surface and agriculture following heavy rain is common in inland aquatic systems and can cause profoundly effects on the growth of macrophytes, especially when combined with low light. In this study, three patterns of NH4-N pulse (differing in magnitude and frequency) were applied to examine their effects on the growth of three submersed macrophytes, namely, Myriophyllum spicatum, Potamogeton maackianus, and Vallisneria natans, in terms of biomass, height, branch/ramet number, root length, leaf number, and total branch length under high and low light. Results showed that NH4-N pulse caused negative effects on the biomass of the submerged macrphytes even on the 13th day after releasing NH4-N pulse. The negative effects on M. spicatum were significantly greater than that on V. natans and P. maackianus. The effects of NH4-N pulse on specific species depended on the ammonium loading patterns. The negative effects of NH4-N pulse on P. maackianus were the strongest at high loading with low frequency, and on V. natans at moderate loading with moderate frequency. For M. spicatum, no significant differences were found among the three NH4-N pulse patterns. Low light availability did not significantly aggregate the negative effects of NH4-N pulse on the growth of the submersed macrophytes. Our study contributes to revealing the roles of NH4-N pulse on the growth of aquatic plants and its species specific effects on the dynamics of submerged macrophytes in lakes.

For submersed macrophytes, carbon (C) and nitrogen (N) metabolism is a central factor affecting growth and survival under low light availability. Three common submersed macrophytes, Vallisneria natans, Potamogeton maackianus, and Potamogeton malaianus, were grown at five water depths (1.0, 2.5, 4.0, 5.5, and 7.0 m) to explore mechanism of low light adaptation in terms of C/N metabolism by examining relative growth rate (RGR) and contents of soluble carbohydrate (SC), starch, total carbon (TC), free amino acid (FAA) and total nitrogen (TN) in leaf, stem and root of the plants. With increasing water depth, P. malaianus, P. maackianus and V. natans initiated dying at 4.0 m, 5.5 m and 7.0 m water depths, respectively. natans showed higher RGR than the other two species. For all the plants, the FAA contents increased with increasing water depth, except for the roots of P. maackianus. The TN contents showed a unimodal curve along water depths with the highest in moderate water depth, except for P. malaianus and-the roots of V. natans. For V. natans and P. maackianus, the C metabolic indices (SC, starch, and TC) showed a unimodal curve along water depths with the lowest in moderate water depth in the leaves and stems, except for TC contents in the leaves of P. maackianus. Compared with P. maackianus and P. malaianus, lower SC and FAA contents and higher starch storage in V. natans contributed to its higher tolerance to deeper depths. The nonlinear changes in metabolite contents along water depths for V. natans and P. maackianus demonstrated complex mechanism for low light adaptation, and thus partly explained the wider ranges of colonizing water depths than P. malaianus. (C) 2015 Elsevier B.V. All rights reserved.

Biochar is a good adsorbent for water pollutants. However, the effects of biochar on aquatic organisms are not well understood. In this study, different amounts of biochar (CK, 0 mg/g; T1, 10 mg/g; T2, 30 mg/g) were added to sediment to study changes in water quality and its impact on three submerged macrophytes (Hydrilla verticillata, Vallisneria natans, and Ceratophyllum demersum) and the sediment microbial community. The results indicated that biochar treatments significantly increased the water pH and conductivity. Compared with the initial values, the total phosphorus (P) contents in the water of the CK, T1, and T2 treatments decreased by 78.5%, 95.0%, and 58.3%, respectively, while the total nitrogen contents increased by 26.26%, −5.81%, and 19.70%, respectively. Compared with those in CK, the relative growth rates of H. verticillata, V. natans, and C. demersum in T1 increased by 28.4%, 163.1%, and 61.3%, respectively, while those in T2 showed no significant difference except that the growth rates of H. verticillata decreased by 17.7%. The P contents of the three submerged macrophytes increased with the increase of biochar addition, except that there was no significant difference between T2 and CK for H. verticillata. Biochar treatments reduced the biomass of total microbial, bacterial, and fungal phospholipid fatty acids in the sediment for H. verticillata and V. natans, and they increased fungal: bacterial ratios in the low-dose biochar treatments for V. natans and C. demersum. This study demonstrates that the addition of biochar to sediment significantly increased the pH and conductivity, and decreased total P contents in the water. Low-dose biochar treatments were more beneficial for water quality improvements and the growth of submerged macrophytes than high-dose biochar.

Correction for ‘Investigation of heart lipid changes in acute β-AR activation-induced sudden cardiac death by time-of-flight secondary ion mass spectrometry’ by Jia-Qian Lou, et al., Analyst, 2020, DOI: 10.1039/d0an00768d.

It is extremely challenging to deploy computing-intensive convolutional neural networks (CNNs) with rich parameters in mobile devices because of their limited computing resources and low power budgets. Although prior works build fast and energy-efficient CNN accelerators by greatly sacrificing test accuracy, mobile devices have to guarantee high CNN test accuracy for critical applications, e.g., unlocking phones by face recognitions. In this paper, we propose a 3D XPoint ReRAM-based process-in-memory architecture, 3DICT, to provide various test accuracies to applications with different priorities by lookup-based CNN tests that dynamically exploit the trade-off between test accuracy and latency. Compared to the state-of-the-art accelerators, on average, 3DICT improves the CNN test performance per Watt by 13% ~ 61X and guarantees 9-year endurance under various CNN test accuracy requirements.

With extensive pharmacological actions, quercetin has anti‑oxidant, free radical scavenging, anti‑tumor, anti‑inflammatory, anti‑bacterial and anti‑viral activity. Quercetin also reduces blood glucose and reduces high blood pressure, and has immunoregulation and cardiovascular protection functions. Additionally, it has been reported that it can reduce depression. The current study evaluated whether quercetin protects against inflammation, matrix metalloproteinase‑2 (MMP‑2) activation and apoptosis induction in a rat model of cardiopulmonary resuscitation (CPR), and whether Bmi‑1 expression was involved in the effects. In CPR model rats, treatment with quercetin significantly recovered left ventricular ejection fraction, left ventricular fractional shortening, ejection fraction (%), and left ventricle weight/body weight. Treatment with quercetin significantly inhibited ROS generation, inflammation and MMP‑2 protein expression in the rat model CPR. Finally, quercetin significantly suppressed caspase‑3 activity and activated Bmi‑1 protein expression in the rat model of CPR. The results demonstrated that quercetin protects against inflammation, MMP‑2 activation and apoptosis induction in a rat model of CPR, and that this may be mediated by modulating Bmi‑1 expression.

Anthocyanins are responsible for the different colors of ornamental plants. Grape hyacinth (Muscari armeniacum), a monocot plant with bulbous flowers, is popular for its fascinating blue color. In the present study, we functionally characterized an R2R3-MYB transcription factor gene MaAN2 from M. armeniacum. Our results indicated that MaAN2 participates in controlling anthocyanin biosynthesis. Sequence alignment and phylogenetic analysis suggested that MaAN2 belonged to the R2R3-MYB family AN2 subgroup. The anthocyanin accumulation of grape hyacinth flowers was positively correlated with the expression of MaAN2. And the transcriptional expression of MaAN2 was also consistent with that of M. armeniacum dihydroflavonol 4-reductase (MaDFR) and M. armeniacum anthocyanidin synthase (MaANS) in flowers. A dual luciferase transient expression assay indicated that when MaAN2 was co-inflitrated with Arabidopsis thaliana TRANSPARENT TESTA8 (AtTT8), it strongly activated the promoters of MaDFR and MaANS, but not the promoters of M. armeniacum chalcone synthase (MaCHS), M. armeniacum chalcone isomerase (MaCHI), and M. armeniacum flavanone 3-hydroxylase (MaF3H). Bimolecular fluorescence complementation assay confirmed that MaAN2 interacted with AtTT8 in vivo. The ectopic expression of MaAN2 in Nicotiana tabacum resulted in obvious red coloration of the leaves and much redder flowers. Almost all anthocyanin biosynthetic genes were remarkably upregulated in the leaves and flowers of the transgenic tobacco, and NtAn1a and NtAn1b (two basic helix–loop–helix anthocyanin regulatory genes) were highly expressed in the transformed leaves, compared to the empty vector transformants. Collectively, our results suggest that MaAN2 plays a role in anthocyanin biosynthesis.

Field Programmable Gate Array (FPGA) has been widely adopted as modern reconfigurable computing platforms. Traditionally, the storage elements in FPGAs are static RAM (SRAM), which has large leakage power and limited scalability. Recently, non-volatile memory (NVM) is proposed to replace the SRAM in FPGA systems for static power and density considerations, at the cost of inducing larger dynamic power. Hybrid FPGAs combine the advantages of SRAM and NVM by employing both SRAM and NVM as logic storage elements. Although the feasibility of hybrid FPGA has been confirmed, the design flow has not fully explored the hybrid features yet, resulting in inferior system performance. Besides, traditional design flow does not consider the reconfiguration cost, which may prolong the reconfiguration procedures and thus degrade the system performance in dynamically reconfigurable FPGA systems. This work proposes a runtime and reconfiguration dual aware placement strategy for dynamically reconfigurable hybrid architecture. The proposed scheme considers the tradeoff between runtime and dynamic reconfiguration latency and optimizes the overall performance of the reconfigurable system. Evaluation shows that the proposed scheme improves the system performance by 14.6% for SRAM-MRAM hybrid FPGAs compared with the default placement strategy.

Grape hyacinth (Muscari spp.) is a popular ornamental bulbous perennial famous for its blue flowers. To understand the chemical basis of the rich blue colors in this plant, anthocyanin profiles of six blue flowering grape hyacinths as well as one pink and one white cultivar were determined using high-performance liquid chromatography and mass spectrometry. Along with two known compounds, eight putative anthocyanins were identified in the tepals of grape hyacinth for the first time. The accumulation and distribution of anthocyanins in the plant showed significant cultivar and flower development specificity. Violet-blue flowers mainly contained simple delphinidin-type anthocyanins bearing one or two methyl-groups but no acyl groups, whereas white and pink flowers synthesised more complex pelargonidin/cyanidin-derivatives with acyl-moieties but no methyl-groups. The results partially reveal why solid blue, orange or red flowers are rare in this plant in nature. In addition, pelargonidin-type anthocyanins were found for the first time in the genus, bringing more opportunities in terms of breeding of flower color in grape hyacinth.

Summary Through a combination of metabolite analysis with transcriptome sequencing, a new hypothesis was proposed to explain the lack of colour phenotype of the white variant of the blue grape hyacinth., Grape hyacinth (Muscari) is an important ornamental bulbous plant with an extraordinary blue colour. Muscari armeniacum, whose flowers can be naturally white, provides an opportunity to unravel the complex metabolic networks underlying certain biochemical traits, especially colour. A blue flower cDNA library of M. armeniacum and a white flower library of M. armeniacum f. album were used for transcriptome sequencing. A total of 89 926 uni-transcripts were isolated, 143 of which could be identified as putative homologues of colour-related genes in other species. Based on a comprehensive analysis relating colour compounds to gene expression profiles, the mechanism of colour biosynthesis was studied in M. armeniacum. Furthermore, a new hypothesis explaining the lack of colour phenotype of the grape hyacinth flower is proposed. Alteration of the substrate competition between flavonol synthase (FLS) and dihydroflavonol 4-reductase (DFR) may lead to elimination of blue pigmentation while the multishunt from the limited flux in the cyanidin (Cy) synthesis pathway seems to be the most likely reason for the colour change in the white flowers of M. armeniacum. Moreover, mass sequence data obtained by the deep sequencing of M. armeniacum and its white variant provided a platform for future function and molecular biological research on M. armeniacum.

Grape hyacinth (Muscari spp.) is a popular ornamental plant with bulbous flowers noted for their rich blue color. Muscari species have been thought to accumulate delphinidin and cyanidin rather than pelargonidin-type anthocyanins because their dihydroflavonol 4-reductase (DFR) does not efficiently reduce dihydrokaempferol. In our study, we clone a novel DFR gene from blue flowers of Muscari. aucheri. Quantitative real-time PCR (qRT-PCR) and anthocyanin analysis showed that the expression pattern of MaDFR had strong correlations with the accumulation of delphinidin, relatively weak correlations with cyanidin, and no correations with pelargonidin. However, in vitro enzymatic analysis revealed that the MaDFR enzyme can reduce all the three types of dihydroflavonols (dihydrokaempferol, dihydroquercetin, and dihydromyricetin), although it most preferred dihydromyricetin as a substrate to produce leucodelphinidin, the precursor of blue-hued delphinidin. This indicated that there may be other functional genes responsible for the loss of red pelargonidin-based pigments in Muscari. To further verify the substrate-specific selection domains of MaDFR, an assay of amino acid substitutions was conducted. The activity of MaDFR was not affected whenever the N135 or E146 site was mutated. However, when both of them were mutated, the catalytic activity of MaDFR was lost completely. The results suggest that both the N135 and E146 sites are essential for the activity of MaDFR. Additionally, the heterologous expression of MaDFR in tobacco (Nicotiana tabacum) resulted in increasing anthocyanin accumulation, leading to a darker flower color, which suggested that MaDFR was involved in color development in flowers. In summary, MaDFR has a high preference for dihydromyricetin, and it could be a powerful candidate gene for genetic engineering for blue flower colour modification. Our results also make a valuable contribution to understanding the basis of color variation in the genus Muscari.

Purple turnip Brassica rapa ssp. rapa is highly appreciated by consumers but the metabolites and molecular mechanisms underlying the root skin pigmentation remain open to study. Herein, we analyzed the anthocyanin composition in purple turnip (PT) and green turnip (GT) at five developmental stages. A total of 21 anthocyanins were detected and classified into the six major anthocynanin aglycones. Distinctly, PT contains 20 times higher levels of anthocyanins than GT, which explain the difference in the root skin pigmentation. We further sequenced the transcriptomes and analyzed the differentially expressed genes between the two turnips. We found that PT essentially diverts dihydroflavonols to the biosynthesis of anthocyanins over flavonols biosynthesis by strongly down-regulating one flavonol synthase gene, while strikingly up-regulating dihydroflavonol 4-reductase (DFR), anthocyanidin synthase and UDP-glucose: flavonoid-3-O-glucosyltransferase genes as compared to GT. Moreover, a nonsense mutation identified in the coding sequence of the DFR gene may lead to a nonfunctional protein, adding another hurdle to the accumulation of anthocyanin in GT. We also uncovered several key members of MYB, bHLH and WRKY families as the putative main drivers of transcriptional changes between the two turnips. Overall, this study provides new tools for modifying anthocyanin content and improving turnip nutritional quality.

Flower-specific promoters can enable transgenic enhancement of valuable ornamental traits, including flower shape and color. However, the identification of strong, tissue-specific promoters remains a limiting factor. To obtain enhanced flower-specific promoters, we constructed four chimeric promoters (p35S-PCHS-Ω, p35S-LCHS-Ω, pOCS-PCHS-Ω and pOCS-LCHS-Ω) combining the 35S or OCS enhancer fused to a 302 bp CHSA core promoter fragment from petunia (PCHS) or a 307 bp CHS core promoter fragment from lily (LCHS), and also containing an omega element (Ω). Each promoter was fused to the β-glucuronidase (GUS) reporter gene, and we examined the levels and tissue specificity of GUS expression in transgenic Torenia fournieri. p35S-PCHS-Ω and p35S-LCHS-Ω drove strong, constitutive GUS expression in all tissues, especially in colored corollas (p35S-PCHS-Ω) or in colored corollas and roots (p35S-LCHS-Ω). pOCS-PCHS-Ω drove stronger GUS expression in colored corollas than in other tissues but expression was weaker than that of p35S-PCHS-Ω. pOCS-LCHS-Ω drove GUS in colored corollas but also in roots. Among the four chimeric promoters, pOCS-PCHS-Ω exhibited stronger activity only in colored corollas, making it useful for transgenic enhancement of floral traits, such as expressing ‘blue genes’ in lily to produce new lines with blue flowers.