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In modern power systems, the uncertainty and volatility of generation and loads greatly increase the balance discrepancy between the power supply and demand, creating major potential security hazards. To limit out‐of‐bound frequencies, an effective frequency control method for power systems with interval uncertain disturbances is proposed. Based on the state space model of the system frequency response with delays, linear matrix inequalities are constructed based on the input‒output finite‐time stability of the system frequency. By searching for the output feedback gain and altering the time delay with the Padé approximation, the feasibility of the linear matrix inequalities is improved, and a frequency controller is designed. The simulation results show that the proposed method can effectively control frequency deviations. When the closed‐loop system is disturbed by uncertain power fluctuations, its frequency will always remain within the allowable range to ensure the secure operation of the power system. [ABSTRACT FROM AUTHOR]

Based on the Climate Precipitation Center Morphing (CMORPH) precipitation data and the fifth-generation ECMWF reanalysis (ERA5) data, moist static energy (MSE) diagnosis for 14 cases of southerly warm-sector heavy rainfall with warm shear (WSWR) along the Yangtze-Huaihe coastal area (YHCA) was conducted. The results indicate that the vertically integrated MSE tendency peaks before the precipitation reaches its maximum. This suggests a rapid MSE accumulation leading up to precipitation onset, with moist enthalpy advection dominantly influencing this increase. The vertical advection of MSE is negative, suggesting that upward motions and rainfall play a crucial role in consuming MSE. Vertical integrated MSE budget analysis for the nine cases of nocturnal rain shows that moist enthalpy advection was the primary contributor, driven mainly by meridional latent energy advection. Scale analysis shows that the combination of meridional disturbance wind and the mean specific humidity field results in pronounced meridional latent energy advection. For the five cases of non-nocturnal rain, the net energy flux was dominant before the onset of precipitation, primarily driven by clear-sky net shortwave radiation (SWCS). The meridional internal energy advection also makes a substantial contribution. The scale analysis indicates that the combined effects of the meridional disturbance wind and the average temperature field lead to significant meridional internal energy advection. [ABSTRACT FROM AUTHOR]

In modern power systems, the impact of random power sources and loads on power systems is increasing, resulting in threatened system frequency security. However, traditional methods are often not comprehensive in modelling randomness, and there is no analytical method to assess the frequency response of power systems under uncertain power fluctuations. Here, the power fluctuation in a power system is regarded as an interval random quantity. An analytical prediction method of the power system frequency deviation under uncertain power fluctuation is proposed. Through further deduction, the allowable range of power fluctuation under the premise of secure frequency deviation can also be defined, which provides a reference for frequency security and accident prevention in power systems. Numerical simulations with the model of the East China Power Grid demonstrate that the proposed analytical method can delimit the response interval of system frequency deviation well, and the backstepping calculation can also delimit the allowable range of power fluctuation to ensure the secure operation of the system. [ABSTRACT FROM AUTHOR]

A strong and tough Ta/TaHfC2‐laminated composite was proposed and investigated in terms of its thermoablative behavior under plasma flame for a medium–long time (30–120 s) beyond 2517 K. In comparison to TaHfC2, the composite performed a better thermal shock resistance but an equivalent linear ablation rate (−5.40 vs. −4.08 μm/s) after ablation for 30 s. With extending the ablation time, the linear ablation rate of the composite increases. Combined with the characterization results of the ablative layer and the established volatile phase diagram at 2273 K, it was found that the composite mainly undergoes active oxidation, passive oxidation, and dissolution of oxygen during the ablation, whereas its ablative layer mainly experiences the sintering, solid solution, and loss processes of oxides. The reason the composite possesses a good ablation resistance is because the introduction of Ta‐foil‐improved toughness as well as protective effect of the ablative layer of TaHfC2. [ABSTRACT FROM AUTHOR]

Under the omni-channel supply chain by mobile internet, considering both cooperation and competition, this article establishes the pricing model before and after the integration of the omni-channel supply chain by mobile internet and the coordination strategy model under the mobile internet e-commerce logistics cooperation, so as to obtain the wholesale price decision and retail price decision and compensation decisions etc. of supplier S. Furthermore, it can also obtain the corresponding price of retailer T accordingly. Based on the analysis of the above two models, numerical simulations are carried out to compare the optimal decision-making volume before and after the integration of the omni-channel supply chain by mobile internet and the overall profit level. With the help of the numerical simulation results of the above models, the effectiveness of the integration of the omni-channel supply chain by mobile internet is demonstrated which achieving win-win and multi-win in both greater breadth and depth in the supply chain. [ABSTRACT FROM AUTHOR]

Red raspberry is a kind of fruit with high nutritional values. To evaluate the comprehensive quality of 24 red raspberry varieties in Northeast China, physicochemical properties, bioactive compounds and sensory characteristics were measured, followed by principal component analysis (PCA) and cluster analysis (CA). Altogether, eight important property indexes for processing attributes were selected out using PCA, including titratable acidity (TAC), sugar-acid ratio (SAR), pH, length, diameter, weight, sucrose and citric acid. Six individual sugars, including l-rhamnose monohydrate, fructose, glucose, sucrose, maltose and d-trehalose anhydrous, as well as eight organic acids, including oxalic acid, tartaric acid, malic acid, α-ketoglutaric acid, lactic acid, citric acid, fumaric acid and succinic acid, were identified in red raspberry. The two main clusters according to individual sugar, organic acids and SAR indicated that varieties including 'European red', 'DNS9', 'Bulgaskc', 'Canby' and 'Samodiva' were suitable for fresh-eating or processing to juice or other products directly because they had suitable SAR; other varieties with relatively low SAR were unsuitable for fresh-eating and need to adjust their excessive sour taste during processing. [ABSTRACT FROM AUTHOR]

Ta‐Hf‐C ternary ceramics are good candidates for structural components used in extreme thermal environment. However, intrinsic brittleness greatly restricts their applications in reality. Here, we report a novel TaHfC2‐based composite with superior strength and toughness by employing Ta foil as interlayers to generate a multi‐scale laminated structure together with the in situ formed Ta2C MXene during sintering. Owing to the unique composition and microstructure, the tensile strength, shear strength, fracture toughness (KIC), and work of fracture of Ta/TaHfC2 have reached 233 ± 12 MPa, 64 ± 6 MPa, 13.16 ± 0.03 MPa·m1/2, and 1726 ± 448 J/m2 simultaneously, and all showed substantial increments when compared with TaHfC2 monolithic ceramic and related Ta‐Hf‐C materials as showed in literatures. This study significantly improved the toughness of TaHfC2, and it provides a new high‐performance thermal structural material for the aerospace industry as well as a new idea for toughening ultra‐high temperature ceramics (UHTCs) of transition metal carbides. [ABSTRACT FROM AUTHOR]

The effects of Citri Reticulatae Pericarpium (CRP) and grapefruit juice (GFJ) on the pharmacokinetics of omeprazole were investigated in this study. Sprague–Dawley rats were pretreated with CRP decoction or GFJ for 28 consecutive days. After a single intragastric administration of 6.0 mg/kg, the concentration of omeprazole in the plasma was determined by high‐performance liquid chromatography (HPLC), and the pharmacokinetic parameters were calculated by Kinetica software 5.0. A high‐performance liquid chromatography‐quadrupole‐time‐of‐flight mass spectrometry (HPLC‐Q‐TOF‐MS) method was established to identify the chemical components in CRP decoction and GFJ. The results showed that the AUCt–∞ was significantly increased when coadministrated with CRP. The AUC0‐t and AUC0–∞ was remarkably increased; the Cl was decreased when coadministrated with GFJ. A total of 31 and 28 bioactive compounds were identified in the CRP decoction and GFJ, respectively. Flavonoids and furanocoumarins, including hesperidin, hesperetin, naringenin, sinensetin, tangeretin, nobiletin, and 6′,7′‐dihydroxybergamottin, were simultaneously identified in CRP decoction and GFJ. This study indicates that the increased bioavailability of omeprazole may be due to the inhibition of hepatic cytochrome P450 enzymes, and the systemic exposure should be monitored when concomitant administration with CRP and GFJ. Practical applications: Citri Reticulatae Pericarpium (CRP) has been widely consumed as a daily condiment, functional food, and a traditional Chinese medicine. Omeprazole, primary metabolized by CYP450 enzymes, was usually coadministered with CRP for the treatment of gastrointestinal disease. Studies have confirmed that much fruit juices, including grapefruit juice, may affect drug metabolism enzymes. CRP and grapefruit (Citrus paradisi Macf.) belong to the genus Citrus and family Rutaceae with different species. Therefore, the pharmacokinetic interaction of CRP decoction and grapefruit juice with omeprazole is worthy of attention. The results of this study can provide basic pharmacological data support for the safe and effective clinical use of omeprazole. It can also provide a theoretical basis for the development of new functional products and daily application of CRP. [ABSTRACT FROM AUTHOR]

Background: Previous studies have described the effects of different drugs in preventing ovarian hyperstimulation syndrome (OHSS). However, the efficacies of those drugs in preventing OHSS remain inconclusive. Methods: We searched the PubMed, Web of Science, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) databases. A network meta-analysis of randomized controlled trials (RCTs) was performed up to August 2021. We investigated the following drugs in our study: aspirin, albumin, metformin, calcium, cabergoline, quinagolide, letrozole, hydroxyethyl starch (HES), and glucocorticoids. The primary outcome was the incidence rate of moderate-to-severe OHSS, with the results presented as risk ratios (RRs) with 95% confidence intervals (CIs). Results: The incidence of moderate-to-severe OHSS was significantly reduced by calcium administration (risk ratios [RR] 0.14, 95% confidence interval [CI]: 0.04, 0.46) (grade: high), HES (RR 0.25, 95% CI 0.07, 0.73) (grade: high), and cabergoline (RR 0.43, 95% CI 0.24, 0.71) (grade: moderate). The surface under the cumulative ranking curve (SUCRA) indicated that calcium (SUCRA, 92.4%) was the most effective intervention for preventing moderate-to-severe OHSS. These drugs were safe and did not affect clinical pregnancy, miscarriage, or live birth rates. Conclusion: Calcium, HES, and cabergoline could effectively and safely prevent moderate-to-severe OHSS, with calcium as the most effective intervention. [ABSTRACT FROM AUTHOR]

FBN1 encodes asprosin, a glucogenic hormone, following furin cleavage of the C‐terminus of profibrillin 1. Based on evolutionary conservation between FBN1 and FBN2, together with conserved furin cleavage sites, we identified a peptide hormone placensin encoded by FBN2 based on its high expression in trophoblasts of human placenta. In primary and immortalized murine hepatocytes, placensin stimulates cAMP production, protein kinase A (PKA) activity, and glucose secretion, accompanied by increased expression of gluconeogenesis enzymes. In situ perfusion of liver and in vivo injection with placensin also stimulate glucose secretion. Placensin is secreted by immortalized human trophoblastic HTR‐8/SVneo cells, whereas placensin treatment stimulates cAMP‐PKA signaling in these cells, accompanied by increases in MMP9 transcripts and activities, thereby promoting cell invasion. In pregnant women, levels of serum placensin increase in a stage‐dependent manner. During third trimester, serum placensin levels of patients with gestational diabetes mellitus are increased to a bigger extent compared to healthy pregnant women. Thus, placensin represents a placenta‐derived hormone, capable of stimulating glucose secretion and trophoblast invasion. Synopsis: This study identifies placensin as a glucogenic hormone that stimulates hepatic cAMP and glucose production, as well as invasion of placental cells. Serum placensin levels increase during pregnancy and this increase is higher in patients with gestational diabetes mellitus. Human placenta secretes a glucogenic hormone called placensin.Placensin stimulates hepatic glucose and cAMP production.Placesin also promotes placental cell invasiveness.Serum placensin levels increase during pregnancy.Patients with gestational diabetes mellitus display a more prominent increase in serum placensin levels. [ABSTRACT FROM AUTHOR]

Study Question: Does amphiregulin (AREG), the most abundant and important epidermal growth factor receptor (EGFR) ligand in the follicular fluid, regulate aromatase expression in human granulosa-lutein (hGL) cells?Summary Answer: AREG mediates the hCG-induced up-regulation of aromatase expression and estradiol (E2) production in hGL cells.What Is Known Already: AREG expression and secretion are rapidly induced by hCG in hGL cells and mediate physiological functions of LH/hCG in the ovary. EGFR protein is expressed in follicles not only in the pre-ovulatory phase but also throughout the luteal phase of the menstrual cycle. After the LH surge, the human corpus luteum secretes high levels of E2, which regulates various luteal cell functions. Aromatase is an enzyme responsible for a key step in the biosynthesis of E2. However, whether AREG regulates aromatase expression and E2 production in hGL cells remains unexplored.Study Design, Size, Duration: This study is an experimental study performed over a 1-year period. In vitro investigations examined the role of AREG in the regulation of aromatase expression and E2 production in primary hGL cells.Participants/materials, Setting, Methods: Primary hGL cells were obtained from women undergoing IVF treatment in an academic research center. Aromatase mRNA and protein levels were examined after exposure of hGL cells to recombinant human AREG, hCG or LH. The EGFR tyrosine kinase inhibitor AG1478, PI3K inhibitor LY294002 and siRNAs targeting EGFR, LH receptor, StAR and AREG were used to verify the specificity of the effects and to investigate the underlying molecular mechanisms. Reverse transcription quantitative real-time PCR (RT-qPCR) and western blot were used to measure the specific mRNA and protein levels, respectively. Follicular fluid and serum were collected from 65 infertile women during IVF treatment. Pearson's correlation analysis was performed to examine the correlation coefficient between two values.Main Results and the Role Of Chance: Treatment of hGL cells with AREG-stimulated aromatase expression and E2 production. Using pharmacological inhibitors and specific siRNAs, we revealed that AREG-stimulated aromatase expression and E2 production via EGFR-mediated activation of the protein kinase B (AKT) signaling pathway. In addition, inhibition of EGFR activity and AREG knockdown attenuated hCG-induced up-regulation of aromatase expression and E2 production. Importantly, the protein levels of AREG in the follicular fluid were positively correlated with the E2 levels in serum after 2 days of oocyte pick-up and in the follicular fluid of IVF patients.Large-scale Data: N/A.Limitations, Reasons For Caution: The in vitro setting of this study is a limitation that may not reflect the real intra-ovarian microenvironment. Clinical data were obtained from a small sample size.Wider Implications Of the Findings: Our results provide the first evidence that hCG-induced AREG contributes to aromatase expression and E2 production in the luteal phase of the menstrual cycle. A better understanding of the hormonal regulation of female reproductive function may help to develop new strategies for the treatment of clinical infertility.Study Funding/competing Interest(s): This work was supported by the National Natural Science Foundation of China for Young Scientists (81601253), the specific fund of clinical medical research of Chinese Medical Association (16020160632) and the Foundation from the First Affiliated Hospital of Zhengzhou University for Young Scientists to Lanlan Fang. This work was also supported by an operating grant from the National Natural Science Foundation of China (81820108016) to Ying-Pu Sun. All authors declare no conflict of interest. [ABSTRACT FROM AUTHOR]

This paper proposes an analytic method for the amplitude estimation of the forced oscillation under stochastic continuous disturbances (SCDs). There is considerable interest in the integration of intermittent renewable energy resources into a power system, which leads to the power system in an environment with SCDs. Thus, the forced oscillation issues under SCDs are of concern. In this paper, the SCDs are described as continuous-time stochastic processes, and then the systems under SCDs are modeled by stochastic differential algebraic equations. Furthermore, by employing stochastic theory, an efficient analytic method for calculating the statistics of system states during the forced oscillation is proposed. Moreover, a novel forced oscillation phenomenon, which presents system states oscillate with stationary distributions under SCDs, is clearly characterized and theoretically explained. Based on the proposed analytic method, a scheme is put forth to estimate amplitudes of system states during forced oscillation under SCDs. Finally, compared to Monte Carlo simulation, the proposed scheme has two significant advantages. First, the proposed scheme offers a fast and effective solution for engineering applications. Second, the impact mechanism of SCDs on forced oscillation in power system is clearer, by the proposed scheme. [ABSTRACT FROM AUTHOR]

Abstract: A novel molten salt synthesis route has been developed to prepare ternary La1‐xCexB6 (x = 0.2, 0.4, 0.6, 0.8), using LaCl3, CeCl3, and NaBH4 as reactants and eutectic LiCl/KCl salt as molten salt medium. All the synthesized ternary La1‐xCexB6 are single‐phase solid solution, and their lattice constant decreases linearly with increasing x. Morphology, microstructure, and elements composition of La0.6Ce0.4B6 which is a typical representative of the series of La1‐xCexB6 are analyzed in detail. [ABSTRACT FROM AUTHOR]

With the growing integration of renewable power generation, plug-in electric vehicles, and other sources of uncertainty, increasing stochastic continuous disturbances are brought to power systems. The impact of stochastic continuous disturbances on power system transient stability attracts significant attention. To address this problem, this paper proposes an analytical assessment method for transient stability of multimachine power systems under stochastic continuous disturbances. In the proposed method, a probability measure of transient stability is presented and analytically solved by stochastic averaging. Compared with the conventional method (Monte Carlo simulation), the proposed method is many orders of magnitude faster, which makes it very attractive in practice when many plans for transient stability must be compared or when transient stability must be analyzed quickly. Also, it is found that the evolution of system energy over time is almost a simple diffusion process by the proposed method, which explains the impact mechanism of stochastic continuous disturbances on transient stability in theory. [ABSTRACT FROM PUBLISHER]

Lanthanum hexaboride (LaB 6 ) nanoparticles were successfully synthesized via the reaction of lanthanum trichloride (LaCl 3 ) and sodium borohydride (NaBH 4 ) in a molten KCl/LiCl eutectic salt. The changes in the phase composition and morphology of LaB 6 as a function of temperature were systemically investigated. By increasing the temperature from 600 °C to 800 °C, the crystallinity of LaB 6 particles increased and the sphere-like morphology of 49.0 nm changed to the cubic shape of 94.7 nm. Additionally, the microstructure and chemical composition of LaB 6 nanocubes were further characterized, and the possible synthesis mechanism of LaB 6 nanoparticles was proposed based on the experimental results. [ABSTRACT FROM AUTHOR]

Given their totipotency, human embryonic stem cells (hESCs) can differentiate into all types of cells, including adipocytes, and provide an excellent research model for studying diseases associated with the metabolism of adipocytes, such as obesity and diabetes mellitus. Epigenetic regulation, including DNA methylation and histone modification, plays an essential role in the development and differentiation of hESCs. Lysine-specific demethylase 1 (LSD1), a well-characterized histone-modifying enzyme, demethylates dimethylated histone H3 lysine 4 (H3K4) through a flavin adenine dinucleotide (FAD)-dependent oxidative reaction. LSD1 affects the growth and differentiation of human and mouse ES cells, and the deletion of this gene in mice leads to embryonic lethality. Here, we investigated the functional role of LSD1 during the adipogenic differentiation of hESCs involving the demethylation of H3K4. We also found that treating hESCs with the LSD1 inhibitor CBB1007 promotes the adipogenic differentiation of hESCs. [ABSTRACT FROM AUTHOR]

Low-frequency inter-area oscillation is a potentially dangerous phenomenon in power systems involving exchange of power among generators in different areas. In this paper, we study the characteristics of inter-area oscillation by analyzing the distribution of the oscillation energy. First, we introduce equations for the kinetic energy of generators and the potential energy of network branches, derived from the linearization of system dynamic equations. Then, we study the mode composition and the distribution of the generators' kinetic energy during low-frequency oscillations. A modal kinetic energy participation factor is proposed for evaluating the participation of each generator in the oscillation. The relationships among electromagnetic power oscillation distribution, rotor speed deviation, and generator kinetic energy are analyzed and compared to their modal parameter left eigenvectors, right eigenvectors, and linear participation factors, respectively. The bus voltage angle deviation, active power oscillation, and branch potential energy are calculated using the right eigenvector from modal analysis. The distribution characteristics of voltage angle oscillation and branch potential energy in inter-area oscillation is developed. The simulation results for a four-generator two-area system and the New England 10-machine 39-bus system illustrate the feasibility and validity of the proposed theory and method for analysis of inter-area oscillations. [ABSTRACT FROM AUTHOR]

To study the association between ambient air pollutant exposure during the follicular phase and in vitro fertilization (IVF) outcomes. A single-center retrospective analysis. Henan Province, China. Patients (n = 6659) living in Zhengzhou, Henan Province in central China who underwent their first IVF cycle at the First Affiliated Hospital of Zhengzhou University between 2013 and 2019 were included for analysis. None. The relationships between PM 2.5 , PM 10 , and AQI (Air Quality Index) with IVF outcomes during the follicular phase (period I, 85 days before oocyte retrieval; period II, gonadotrophin start to oocyte retrieval). Compared with the bottom tertile, exposure to the top PM 2.5 and PM 10 tertiles during period I was associated with decreased clinical pregnancy (PM 2.5 : adjusted odds ratio [OR], 0.838%, and 95% confidence interval [CI], 0.723 and 0.971; PM 10 : adjusted OR, 0.818%, and 95% CI, 0.705 and 0.950), and decreased live birth rate (PM 2.5 : adjusted odds ratio [OR], 0.852%, and 95% confidence interval [CI], 0.736 and 0.987; PM 10 : adjusted OR, 0.850%, and 95% CI, 0.733 and 0.986), and exposure to the top PM 2.5 tertile during period II adversely affected clinical pregnancy and the live birth rate (adjusted OR, 0.824%, and 95% CI, 0.711 and 0.955; adjusted OR, 0.817%, and 95% CI, 0.706 and 0.945). Compared with the bottom PM 10 tertile, exposure to the middle PM 10 tertile in period II showed decreased clinical pregnancies and live births (adjusted OR, 0.844; 95% CI, 0.729 and 0.978, adjusted OR, 0.846; 95% CI, 0.731 and 0.979). The PM 10 level during period II of the follicular phase tend to adversely affect live birth rate, but the tendency did not reach significance (P = 0.051). Exposure to PM 2.5 and PM 10 before oocyte retrieval has an adverse effect on IVF outcomes. Exposure to PM 2.5 and PM 10 before oocyte retrieval has an adverse effect on IVF outcomes. • During pre85, top PM 2.5 and PM 10 tertiles exposure was associated with decreased clinical pregnancy and live birth rate. • During COH, top PM 2.5 tertile exposure adversely affected clinical pregnancy and the live birth rate. • During COH, PM 10 level tend to adversely affect live birth rate, but the tendency did not reach significance(P=0.051). • No significant association was found between AQI levels and reproductive outcomes. [ABSTRACT FROM AUTHOR]

The aim of our study is to illustrate the role of amphiregulin in trophoblast invasiveness and underlying signal cascades. An immortalized human early extravillous cell line, HTR-8/SVneo, was used for this investigation. Matrigel-transwell invasion assay was used for testing the effects of amphiregulin on cell invasiveness. MMP9 and MMP2 mRNA expression level and activity were measured using Rt-qPCR and zymographic analysis. Cell signals involved in the invasion process were verified using western blot and specific inhibitors. Our results showed that amphiregulin could promote HTR-8/SVneo cell invasiveness without interfering cell proliferation, and significantly upregulate the expression of MMP9 and TIMP-1 mRNAs as well as the ratio of MMP9/TIMP-1. Using specific inhibitors for MEK and PI3K signaling further indicated that, both ERK1/2 and Akt signal pathways were required for amphiregulin-induced cell invasiveness. The co-ordination between ERK1/2 and Akt signaling pathway was needed for the upregulation of MMP9 mRNA, while ERK1/2 was more essential for the upregulation of TIMP-1 mRNA. Meanwhile, we first put forward that the deficiency of amphiregulin expression in trophoblast might be compensated by the upregulation of epidermal growth factor receptor (EGFR) and heparin-binding EGF (HB-EGF) mRNA. ERK1/2 and Akt signaling pathways mediate amphiregulin-induced upregulation of MMP9 mRNA and the MMP9/TIMP-1 ratio, which subsequently contribute to amphiregulin-promotion of HTR-8/SVneo cell invasion. [ABSTRACT FROM AUTHOR]

• No significant association between VEGF SNP and PCOS in general population. • VEGF +405G>C (rs2010963) protects Asian women from PCOS. Vascular endothelial growth factor (VEGF) plays important roles in the pathogenesis of polycystic ovary syndrome (PCOS). Several single nucleotide polymorphisms (SNP) of the VEGF gene have been identified and are associated with the aberrant secretion of VEGF protein. This meta-analysis aimed to evaluate the impact of the VEGF +405G>C (rs2010963), –460C>T (rs833061) and –2578A>C (rs699947) polymorphisms on PCOS susceptibility. A systematic search of the Embase, PubMed, Web of Science and Wanfang databases was carried out to identify relevant studies published before 19 July 2019. Seven eligible studies were included in this meta-analysis involving 1100 patients with PCOS and 1141 control individuals. The pooled analysis revealed no significant association between PCOS risk and the +405G>C (rs2010963), –460C>T (rs833061) or –2578A>C (rs699947) polymorphisms in women. Subgroup analysis by ethnicity indicated that Asian women carrying the VEGF +405C allele had a lower risk of PCOS (C versus G: odds ratio [OR] 0.731, 95% confidence interval [CI] 0.544–0.982, P < 0.05, I 2 = 46.4%; CG versus GG: OR 0.667, 95% CI 0.469–0.948, P < 0.05, I 2 = 18.4%; CC versus GG: OR 0.611, 95% CI 0.390–0.958, P < 0.05, I 2 = 24.3%). The study demonstrates that for all women regardless of ethnicity, no significant associations between VEGF SNP and PCOS were observed; however, +405G>C (rs2010963) may protect Asian women from PCOS. [ABSTRACT FROM AUTHOR]

• Women with the CYP17A1 rs743572 T/C mutation are more susceptible to PCOS. • The mutant genotype CC of rs743572 may increase the PCOS risk in Caucasians. • The recessive model appeared the best model for the association of rs743572 and PCOS. Polycystic ovary syndrome (PCOS) is a multifactorial reproductive and endocrine disease, believed to be caused by aberrant steroid biosynthesis pathways involving cytochrome P450, 17α-hydroxylase (CYP17A1). This meta-analysis aimed to evaluate the association between CYP17A1 polymorphism rs743572 and PCOS risk. Studies on the CYP17A1 gene were retrieved by searching PubMed, Embase and Web of Science and statistical analyses were performed by STATA software. Fifteen eligible studies were included, dated from January 1994 to 19 November 2020, involving 2277 patients with PCOS and 1913 control individuals. Overall, the results showed that the rs743572 T>C mutation was most likely to be associated with PCOS risk under the recessive model, which was further confirmed by heterogeneity analysis and publication bias detection (CC versus CT + TT, odds ratio [OR] 1.24, 95% confidence interval [CI] 1.02–1.50, P = 0.028, I ² = 35.9%). Moreover, subgroup analysis by ethnicity demonstrated that Caucasian but not Asian women carrying the CC genotype of rs743572 had an elevated risk of PCOS (CC versus CT + TT, OR 1.45, 95% CI 1.03–2.06, P = 0.035, I ² = 15.10%, six studies). In conclusion, rs743572 is highly likely to be a risk factor for PCOS, and the mutant genotype CC may increase susceptibility to PCOS in Caucasians rather than Asians. [ABSTRACT FROM AUTHOR]