Accommodation capacity evaluation of renewable energy in power systems considering peak and frequency regulation

With the fast growth of renewable energy, the modern power systems are transitioning to the renewable energy dominated energy systems. However, the intrinsic intermittence and volatility of renewable energy also impose considerable challenges on the power system operation. Hence, it is of great significance to accurately evaluate the renewable energy accommodation capacity (REAC) in power system so as to effectively instruct the sustainable development of renewable energy and to alleviate the ongoing operational burdens. This paper proposes a novel evaluation method of REAC in power system comprehensively considering peak and frequency regulation. First, the mechanism and cost of deep peak regulation of thermal power units are deeply analyzed, and then the frequency dynamics response is modeled explicitly and simplified effectively. Next, a synthetic interaction model of “source-network-storage” is developed with diversified generation units, network and energy storage constraints. Furthermore, a multi-objective optimization model is established considering both economic and technical issues, and a REAC evaluation method is developed by integrating an incremental capacity augment approach with the proposed multi-objective model. Finally, the proposed REAC evaluation method is tested on the modified IEEE 39-bus system, and the numerical results verify the effectiveness of the proposed method

Varying performance of eight evapotranspiration products with aridity and vegetation greenness across the globe

The wide application of the evapotranspiration (ET) products has deepened our understanding of the water, energy and carbon cycles, driving increased interest in regional and global assessments of their performance. However, evaluating ET products at a global scale with varying levels of dryness and vegetation greenness poses challenges due to a relative lack of reference data and potential water imbalance. Here, we evaluated the performance of eight state-of-the-art ET products derived from remote sensing, Land Surface Models, and machine learning methods. Specifically, we assessed their ability to capture ET magnitude, variability, and trend, using 1,381 global watershed water balance ET as a baseline. Furthermore, we created aridity and vegetation categories to investigate performance differences among products under varying environmental conditions. Our results demonstrate that the spatial and temporal performances of the ET products were strongly affected by aridity and vegetation greenness. The poorer performances, such as underestimation of interannual variability and misjudged trend, tend to occur in abundant humidity and vegetation. Our findings emphasize the significance of considering aridity and vegetation greenness into ET product generation, especially in the context of ongoing global warming and greening. Which hopefully will contribute to the directional optimizations and effective applications of ET simulations

Characterization of an Artificial Swine-Origin Influenza Virus with the Same Gene Combination as H1N1/2009 Virus: A Genesis Clue of Pandemic Strain

Pandemic H1N1/2009 influenza virus, derived from a reassortment of avian, human, and swine influenza viruses, possesses a unique gene segment combination that had not been detected previously in animal and human populations. Whether such a gene combination could result in the pathogenicity and transmission as H1N1/2009 virus remains unclear. In the present study, we used reverse genetics to construct a reassortant virus (rH1N1) with the same gene combination as H1N1/2009 virus (NA and M genes from a Eurasian avian-like H1N1 swine virus and another six genes from a North American triple-reassortant H1N2 swine virus). Characterization of rH1N1 in mice showed that this virus had higher replicability and pathogenicity than those of the seasonal human H1N1 and Eurasian avian-like swine H1N1 viruses, but was similar to the H1N1/2009 and triple-reassortant H1N2 viruses. Experiments performed on guinea pigs showed that rH1N1 was not transmissible, whereas pandemic H1N1/2009 displayed efficient transmissibility. To further determine which gene segment played a key role in transmissibility, we constructed a series of reassortants derived from rH1N1 and H1N1/2009 viruses. Direct contact transmission studies demonstrated that the HA and NS genes contributed to the transmission of H1N1/2009 virus. Second, the HA gene of H1N1/2009 virus, when combined with the H1N1/2009 NA gene, conferred efficient contact transmission among guinea pigs. The present results reveal that not only gene segment reassortment but also amino acid mutation were needed for the generation of the pandemic influenza virus

Whole Exome Sequencing Identified a Novel Heterozygous Mutation in HMBS Gene in a Chinese Patient With Acute Intermittent Porphyria With Rare Type of Mild Anemia

Acute intermittent porphyria (AIP) is a rare hereditary metabolic disease with an autosomal dominant mode of inheritance. Germline mutations of HMBS gene causes AIP. Mutation of HMBS gene results into the partial deficiency of the heme biosynthetic enzyme hydroxymethylbilane synthase. AIP is clinically manifested with abdominal pain, vomiting, and neurological complaints. Additionally, an extreme phenotypic heterogeneity has been reported in AIP patients with mutations in HMBS gene. Here, we investigated a Chinese patient with AIP. The proband is a 28-year-old Chinese male manifested with severe stomach ache, constipation, nausea and depression. Proband’s father and mother is normal. Proband’s blood sample was collected and genomic DNA was extracted. Whole exome sequencing and Sanger sequencing identified a heterozygous novel single nucleotide deletion (c.809delC) in exon 12 of HMBS gene in the proband. This mutation leads to frameshift followed by formation of a truncated (p.Ala270Valfs∗2) HMBS protein with 272 amino acids comparing with the wild type HMBS protein of 361 amino acids. This mutation has not been found in proband’s unaffected parents as well as in 100 healthy normal control. According to the variant interpretation guidelines of American College of Medical Genetics and Genomics (ACMG), this variant is classified as “likely pathogenic” variant. Our findings expand the mutational spectra of HMBS gene related AIP which are significant for screening and genetic diagnosis for AIP

Joint Planning of Transmission and Distribution Network Considering Wind-solar Complementarity

The temporal and spatial distribution characteristics of wind power and photovoltaic output are complementary to a certain extent, which can stabilize the volatility of single new energy power generation to a certain extent and improve the ability of the grid to absorb new energy. This paper aims to study the joint planning method of power transmission and distribution network considering the complementary characteristics of wind-solar time and space. First, a wind-solar joint distribution model based on the time-varying Copula theory is established, and a wind-solar output simulation method considering the complementary characteristics of time and space is proposed. Then, taking the system investment and new energy consumption capacity as the optimization goals, and taking the system power balance, line transmission capacity, conventional generator set output and climbing capacity as constraints, the joint planning model of transmission and distribution network is established. At last, the analysis of calculation examples proves that the joint planning model of transmission and distribution network considering the complementary characteristics of wind-solar time and space can significantly improve the capacity of the grid to absorb new energy

Bismuth nanospheres embedded in three-dimensional (3D) porous graphene frameworks as high performance anodes for sodium- and potassium-ion batteries

Bismuth (Bi) has been demonstrated as a promising anode material for both Na-ion batteries (NIBs) and K-ion batteries (KIBs) due to its high theoretical capacity (385mA h g(-1) for NIBs and KIBs). However, Bi undergoes a huge volume change during charge-discharge processes, leading to severe pulverization of Bi particles and structural degradation. Herein, a robust composite possessing a three-dimensional (3D) structure with Bi nanoparticles embedded in 3D macroporous graphene frameworks (Bi@3DGFs) is designed to address these issues. This 3D porous Bi@3DGF composite demonstrates high capacity and stable long-term cycling performance at various current densities for both NIBs and KIBs. As an anode for NIBs, it shows a reversible capacity of 180 mA h g(-1) at a current density as high as 50 A g(-1). The rate capability for KIBs is also unprecedented; it delivers a reversible capacity of 185.2 mA h g(-1) after 2000 cycles at a current density of 10 A g(-1). The excellent electrochemical performance of the Bi@3DGFs is ascribed to the unique structure. The 3D interconnecting pores facilitate the penetration of the electrolyte, leading to direct contact between electrochemically active Bi and the electrolyte, enhancing charge transfer kinetics

An energy-efficient 2.5D through-silicon interposer I/O with self-adaptive adjustment of output-voltage swing

A self-adaptive output swing adjustment is introduced for the design of energy-efficient 2.5D through-silicon interposer (TSI) I/Os. Instead of transmitting signal with large voltage swing, Q-learning based self-adaptive adjustment is deployed to adjust I/O output-voltage swing under constraints of both power budget and bit error rate (BER). Experimental results show that the adaptive 2.5D TSI I/Os designed in 65nm CMOS can achieve an average of 13mW I/O power, 4GHz bandwidth and 3.25pJ/bit energy efficiency for one channel under 10−6 BER, which has 21.42%reduction of power and 14.47% energy efficiency improvement.Accepted versio

Transcriptome Sequencing Reveals Differences between Primary and Secondary Hair Follicle-derived Dermal Papilla Cells of the Cashmere Goat (<i>Capra hircus</i>)

<div><p>The dermal papilla is thought to establish the character and control the size of hair follicles. Inner Mongolia Cashmere goats (<i>Capra hircus</i>) have a double coat comprising the primary and secondary hair follicles, which have dramatically different sizes and textures. The Cashmere goat is rapidly becoming a potent model for hair follicle morphogenesis research. In this study, we established two dermal papilla cell lines during the anagen phase of the hair growth cycle from the primary and secondary hair follicles and clarified the similarities and differences in their morphology and growth characteristics. High-throughput transcriptome sequencing was used to identify gene expression differences between the two dermal papilla cell lines. Many of the differentially expressed genes are involved in vascularization, ECM-receptor interaction and Wnt/β-catenin/Lef1 signaling pathways, which intimately associated with hair follicle morphogenesis. These findings provide valuable information for research on postnatal morphogenesis of hair follicles.</p></div

Association of CDKN2BAS Polymorphism rs4977574 with Coronary Heart Disease: A Case-Control Study and a Meta-Analysis

The goal of our study was to explore the significant association between a non-protein coding single nucleotide polymorphism (SNP) rs4977574 of CDKN2BAS gene and coronary heart disease (CHD). A total of 590 CHD cases and 482 non-CHD controls were involved in the present association study. A strong association of rs4977574 with CHD was observed in females (genotype: p = 0.002; allele: p = 0.002, odd ratio (OR) = 1.57, 95% confidential interval (CI) = 1.18–2.08). Moreover, rs4977574 was more likely to be a risk variant of CHD under the recessive model in females (χ2 = 10.29, p = 0.003, OR = 2.14, 95% CI = 1.31–2.77). A breakdown analysis by age had shown that there was an 87% increased risk of CHD for females younger than 65 years (genotype: χ2 = 14.64, degrees of freedom (df) = 2, p = 0.0002; allele: χ2 = 11.31, df = 1, p = 0.0008, OR = 1.87, 95% CI = 1.30–2.70). Similar observation was also found in males younger than 65 years (genotype: χ2 = 8.63, df = 2, p = 0.04; allele: χ2 = 7.55, df = 1, p = 0.006, OR = 1.45, 95% CI = 1.11–1.90). p values were adjusted by age, sex, smoking, high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C). Meta-analysis of 23 studies among 36,452 cases and 39,781 controls showed a strong association between rs4977574 and the risk of CHD (p &lt; 0.0001, OR = 1.27, 95% CI = 1.22–1.31)