Continuous Synthesis of a Macrocyclic Sulfite of Polyethylene Glycol by Cascaded Continuous Stirred Tank Reactors (CSTRs).

Many macrocyclic compounds are attractive drug-like molecules or intermediates due to their special properties. However, the bulk synthesis of such compounds are hindered by the necessity of using diluted solutions, in order to prevent intermolecular reactions that yields oligomer impurities, thereby resulting in a low production efficiency. Such challenge can be adequately addressed by using continuous reactors, allowing improved efficiency with smaller space footprints. In this work, we proposed a novel continuous process for the synthesis of a macrocyclic sulfite of tetraethylene glycol (PEG4-MCSi), which is a precursor to a very useful building block, PEG4-macrocyclic sulfate (PEG4-MCS). The basic reaction parameters, including stoichiometry and temperature, were first confirmed with small batch reactions, and the effectiveness of coiled reactors and continuous stirred tank reactors (CSTRs) were compared. Cascaded CSTRs were proven to be suitable, and the reaction parameters were subject to further optimization to give a robust continuous process. The process was then tested with 4 parallel runs for up to 64 h. Finally, the merits and demerits of batch and continuous reactions were also compared, demonstrating the suitability of latter in the bulk production of macrocyclic PEG-MCSi compounds.

Continuous Synthesis of a Macrocyclic Sulfite of Polyethylene Glycol by Cascaded Continuous Stirred Tank Reactors (CSTRs).

Invited for the cover of this issue is the group of Long Pan and co-workers at Asymchem Life Sciences (Tianjin) Co. Ltd. The image depicts a novel continuous process for the synthesis of a macrocyclic poly(ethylene glycol) (PEG) sulfite, the precursor to PEG macrocyclic sulfate, a useful building block in PEG chemistry. Read the full text of the article at 10.1002/chem.202304319.

Preparation of PEI-modified nanoparticles by dopamine self-polymerization for efficient DNA delivery.

Achieving efficient and safe gene delivery is of great significance to promote the development of gene therapy. In this work, a polydopamine (PDA) layer was coated on the surface of Fe3 O4 nanoparticles (NPs) by dopamine (DA) self-polymerization, and then magnetic Fe3 O4 NPs were prepared by the Michael addition between amino groups in polyethyleneimine (PEI) and PDA. The prepared Fe3 O4 NPs (named Fe3 O4 @PDA@PEI) were characterized by Fourier transform infrared (FTIR), atomic force microscopy (AFM), and scanning electron microscopy (SEM). As an efficient and safe gene carrier, the potential of Fe3 O4 @PDA@PEI was evaluated by agarose gel electrophoresis, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, fluorescence microscopy, and flow cytometry. The results show that the Fe3 O4 @PDA@PEI NPs are stable hydrophilic NPs with a particle size of 50-150 nm. It can efficiently condense DNA at low N/P ratios and protect it from nuclease degradation. In addition, the Fe3 O4 @PDA@PEI NPs have higher safety than PEI. Further, the Fe3 O4 @PDA@PEI/DNA polyplexes could be effectively absorbed by cells and successfully transfected and exhibit higher cellular uptake and gene transfection efficiency than PEI/DNA polyplexes. The findings indicate that the Fe3 O4 @PDA@PEI NPs have the potential to be developed into a novel gene vector.

Is it worth promoting battery swapping? A social welfare perspective on provider- and consumer-side incentives.

In countries that promote further EV diffusion, battery swapping opens up a market outlet for time-sensitive consumers as well as another green policy channel. To better understand this phenomenon from the perspective of policy-making, this study establishes a Hotelling model of a competitive market comprising a battery swapping service provider and a charging service provider. The analyses of three scenarios, no subsidization, consumer subsidization, and provider subsidization, reveal how to maximize social welfare. Considering subsidy amount, consumer time preferences, service time, and operating costs, the findings provide valuable insights for policymakers. Whereas incentive programs are generally helpful for battery swapping development and social welfare improvement, it is more effective to subsidize service providers than end consumers. Considering subsidy opportunity cost, it is necessary to control incentive amount and make continuous adjustments to promote battery swapping services without harming charging services.

Combination of metformin with liraglutide in treating HAIR-AN syndrome in children: A case report and literature review. / 二甲双胍联合利拉鲁肽治疗儿童HAIR-AN综合征1ä¾‹å¹¶æ–‡çŒ®å¤ä¹ .

Hyperandrogenism-insulin resistance-acanthosis nigricans (HAIR-AN) syndrome is a special and rare subtype of polycystic ovarian syndrome. It can lead to hyperandrogenism (HA), insulin resistance (IR), and acanthosis nigricans (AN) accompanied by acne, hirutism, irregular menstruation, and other androgen excess symptoms. A case of pediatric HAIR-AN syndrome with severe AN was admitted to the Department of Endocrinology, China-Japan Friendship Hospital. The patient's clinical manifestations, laboratory data, imaging features, and gene sequencing were analyzed, and the patient was diagnosed with pediatric HAIR-AN syndrome. Obesity, IR, hyperglycemia, menstrual disorder, and AN were significantly improved after treating with metformin and liraglutide. HAIR-AN syndrome occurs in various forms. When the patient appears unexplained acanthosis nigricans and menstrual disorders, the disease should be considered possible. Early diagnosis and symptomatic supportive treatment can improve the quality of life.

GmPTF1 modifies root architecture responses to phosphate starvation primarily through regulating GmEXPB2 expression in soybean.

Though root architecture modifications may be critically important for improving phosphorus (P) efficiency in crops, the regulatory mechanisms triggering these changes remain unclear. In this study, we demonstrate that genotypic variation in GmEXPB2 expression is strongly correlated with root elongation and P acquisition efficiency, and enhancing its transcription significantly improves soybean yield in the field. Promoter deletion analysis was performed using 5' truncation fragments (P1-P6) of GmEXPB2 fused with the GUS gene in soybean transgenic hairy roots, which revealed that the P1 segment containing three E-box elements significantly enhances induction of gene expression in response to phosphate (Pi) starvation. Further experimentation demonstrated that GmPTF1, a basic-helix-loop-helix transcription factor, is the regulatory factor responsible for the induction of GmEXPB2 expression in response to Pi starvation. In short, Pi starvation induced expression of GmPTF1, with the GmPTF1 product directly binding to the E-box motif in the P1 region of the GmEXPB2 promoter. Plus, both GmPTF1 and GmEXPB2 highly expressed in lateral roots, and were significantly enhanced by P deficiency. Further work with soybean stable transgenic plants through RNA sequencing analysis showed that altering GmPTF1 expression significantly impacted the transcription of a series of cell wall genes, including GmEXPB2, and thereby affected root growth, biomass and P uptake. Taken together, this work identifies a novel regulatory factor, GmPTF1, involved in changing soybean root architecture partially through regulation of the expression of GmEXPB2 by binding the E-box motif in its promoter region.

Exterior computed tomography image reconstruction based on anisotropic relative total variation in polar coordinates.

In computed tomography (CT) image reconstruction problems, exterior CT is an important application in industrial non-destructive testing (NDT). Different from the limited-angle problem that misses part of the rotation angle, the rotation angle of the exterior problem is complete, but for each rotation angle, the projection data through the central region of the object cannot be collected, so that the exterior CT problem is ill-posed inverse problem. The results of traditional reconstruction methods like filtered back-projection (FBP) and simultaneous algebra reconstruction technique (SART) have artifacts along the radial direction edges for exterior CT reconstruction. In this study, we propose and test an anisotropic relative total variation in polar coordinates (P-ARTV) model for addressing the exterior CT problem. Since relative total variation (RTV) can effectively distinguish edges from noises, and P-ARTV with different weights in radial and tangential directions can effectively enhance radial edges, a two-step iteration algorithm was developed to solve the P-ARTV model in this study. The fidelity term and the regularization term are solved in Cartesian and polar coordinate systems, respectively. Numerical experiments show that our new model yields better performance than the existing state-of-the-art algorithms.

An Algorithm for the Pricing and Timing of the Option to make a Two-Stage Investment with Credit Guarantees.

We develop a jump-diffusion model for a guarantee-investment combination financing mode (G-I mode) that is recently popular in financial practice. We assume that a borrower has exclusively an option to invest in a project in two stages. The project's cash flow follows a double exponential jump-diffusion process and it is increased by a growth factor once the second-stage investment is exercised. The first-stage investment cost is financed by a bank loan with the guarantee provided by an insurer, who promises to provide the second-stage investment cost as well as take the lender's all default losses. In return for the guarantee and investment, the borrower pays a guarantee fee upon first investment and grants a fraction of equity upon second investment to the insurer. In sharp contrast to prior papers on guarantee, the guarantee costs are contracted prior to investment. We provide closed-form solutions and produce a numerical algorithm for the timing and pricing of the two investment options.

Ordered PtFeIr Intermetallic Nanowires Prepared through a Silica-Protection Strategy for the Oxygen Reduction Reaction.

Developing efficient and stable Pt-based oxygen reduction reaction (ORR) catalysts is a way to promote the large-scale application of fuel cells. Pt-based alloy nanowires are promising ORR catalysts, but their application is hampered by activity loss caused by structural destruction during long-term cycling. Herein, the preparation of ordered PtFeIr intermetallic nanowire catalysts with an average diameter of 2.6 nm and face-centered tetragonal structure (fct-PtFeIr/C) is reported. A silica-protected strategy prevents the deformation of PtFeIr nanowires during the phase transition at high temperature. The as-prepared fct-PtFeIr/C exhibited superior mass activity for ORR (2.03 A mgPt -1 ) than disordered PtFeIr nanowires with face-centered cubic structure (1.11 A mgPt -1 ) and commercial Pt/C (0.21 A mgPt -1 ). Importantly, the structure and electrochemical performance of fct-PtFeIr/C were maintained after stability tests, showing the advantages of the ordered structure.

Effect of Extracellular Matrix Coating on Cancer Cell Membrane-Encapsulated Polyethyleneimine/DNA Complexes for Efficient and Targeted DNA Delivery In Vitro.

Polyethyleneimine (PEI) has a good spongy proton effect and is an excellent nonviral gene vector, but its high charge density leads to the instability and toxicity of PEI/DNA complexes. Cell membrane (CM) capsules provide a universal and natural solution for this problem. Here, CM-coated PEI/DNA capsules (CPDcs) were prepared through extrusion, and the extracellular matrix was coated on CPDcs (ECM-CPDcs) for improved targeting. The results showed that compared with PEI/DNA complexes, CPDcs had core-shell structures (PEI/DNA complexes were coated by a 6-10 nm layer), lower cytotoxicity, and obvious homologous targeting. The internalization and transfection efficiency of 293T-CM-coated PEI70k/DNA capsules (293T-CP70Dcs) were 91.8 and 74.5%, respectively, which were higher than those of PEI70k/DNA complexes. Then, the internalization and transfection efficiency of 293T-CP70Dcs were further improved by ECM coating, which were 94.7 and 78.9%, respectively. Then, the internalization and transfection efficiency of 293T-CP70Dcs were further improved by ECM coating, which were 94.7 and 78.9%, respectively. Moreover, the homologous targeting of various CPDcs was improved by ECM coating, and other CPDcs also showed similar effects as 293T-CP70Dcs after ECM coating. These findings suggest that tumor-targeted CPDcs may have considerable advantages in gene delivery.

The soybean ß-expansin gene GmINS1 contributes to nodule development in response to phosphate starvation.

Legume biological nitrogen fixation (BNF) is the most important N source in agricultural ecosystems. Nodule organogenesis from the primordia to the development of mature nodules with the ability to fix N2 largely determines BNF capacity. However, nodule growth is often limited by low phosphorus (P) availability, while the mechanisms underlying nodule development responses to P deficiency remain largely unknown. In this study, we found that nodule enlargement is severely inhibited by P deficiency, as reflected by the smaller individual nodule size from a soybean core collection in the field. Wide-ranging natural diversity in nodule size was further identified in soybeans reared in low P soils, with the FC-1 genotype outperforming FC-2 in assessments of nodulation under low P conditions. Among ß-expansin members, GmINS1 expression is most abundantly enhanced by P deficiency in FC-1 nodules, and its transcript level is further displayed to be tightly associated with nodule enlargement. Four single nucleotide polymorphisms discovered in the GmINS1 promoter distinguished the FC-1 and FC-2 genotypes and accounted for the differential expression levels of GmINS1 responses to P deficiency. GmINS1 overexpression led to increases in nodule size, infected cell abundance, and N2 fixation capacity and subsequently promoted increases in N and P content, soybean biomass, and yield. Our findings provide a candidate gene for optimizing BNF capacity responses to low P stress in soybean molecular breeding programs.

Gender-differential effects on blood glucose levels between acarbose and metformin in Chinese patients with newly diagnosed type 2 diabetes: a sub-analysis of the MARCH trial.

Using the data from the trial of Metformin and AcaRbose in Chinese as the initial Hypoglycemic treatment (MARCH), this study was performed to compare the differential effects of acarbose and metformin on glucose metabolism after stratification by gender. Six hundred and forty patients who had finished the whole 48-week follow-up were included. The reduction of haemoglobin A1c (HbA1c) was comparable between acarbose- and metformin-treated patients among either females or males, and it was also similar between males and females treated with either acarbose or metformin for 24 and 48 weeks. The dropping of fasting plasma glucose (FPG) in acarbose-treated females was significantly less than that in metformin-treated females at both 24 and 48 weeks. Furthermore, the decrease of 2-hour postprandial glucose (2hPPG) in acarbose-treated males was significantly greater than that in metformin-treated males at both 24 and 48 weeks. Multiple linear regression analysis showed that drug selection was an independent factor affecting the decrease of FPG in female patients while it independently influenced 2hPPG in males at week 24 and 48. The reductions of FPG and 2hPPG at week 24 and 48 were also significantly different between metformin-treated females and metformin-treated males although gender was not an independent regulating factor. Our study indicates that there might be gender-differential effects on FPG and 2hPPG reduction when the comparisons are made between acarbose and metformin treatments.

Hollow PtFe Alloy Nanoparticles Derived from Pt-Fe3 O4 Dimers through a Silica-Protection Reduction Strategy as Efficient Oxygen Reduction Electrocatalysts.

The development of efficient and stable electrocatalysts for the oxygen reduction reaction (ORR) is critical for the large-scale production of fuel cells. Platinum (Pt) nanoparticle catalysts show excellent performance for ORR, though the high cost of Pt is a limiting factor that directly impacts fuel cell production costs. Alloying Pt with other transition metals is an effective strategy to reduce Pt utilization whilst maintaining good ORR performance. In this work, novel hollow PtFe alloy catalysts were successfully synthesized by high-temperature pyrolysis of SiO2 -coated Pt-Fe3 O4 nanoparticle dimers supported on carbon at 900 °C, followed by SiO2 shell removal and partial dealloying of the PtFe nanoparticles formed using HF. The obtained hollow PtFe nanoparticle catalysts (denoted herein as PtFe-900) showed a 2.3-fold enhancement in ORR mass activity compared to PtFe nanoparticles synthesized without SiO2 protection, and a remarkable 7.8-fold enhancement relative to a commercial Pt/C catalyst. Further, after 10 000 potential cycles, the ORR mass activity of PtFe-900 remained very high (90.9 % of the initial mass activity). The outstanding ORR performance of PtFe-900 can be attributed to the modification of Pt lattice and electronic structure by alloying with Fe at high temperature under the protection of the SiO2 coating. This work guides the development of improved, highly dispersed Pt-based alloy nanoparticle catalysts for ORR and fuel cell applications.

Prevalences and associated factors of electrocardiographic abnormalities in Chinese adults: a cross-sectional study.

BACKGROUND: Electrocardiogram (ECG) is widely used to screen cardiac diseases. To date, no large population study has provided estimates of the prevalences of ECG findings in China. We aim to investigate the prevalences and associated factors of ECG abnormalities in a general population of Chinese adults. METHODS: ECG data were obtained from 34,965 participants in the 2007-2008 China National Diabetes and Metabolic Disorders Study. ECG abnormalities were classified according to the Minnesota coding (MC) criteria. Prevalences of variant ECG abnormalities were calculated. The associations between ECG abnormalities and gender, age and other risk factors for cardiovascular diseases (CVD) were analyzed by multivariate logistic regression test. RESULTS: The prevalences of major arrhythmias were 1.70, 2.37 and 1.04% in the whole population, men and women, respectively. Atrial fibrillation/flutter was found in 0.35% of men and 0.20% of women. ST depression and T abnormalities accounted for 10.96, 7.54 and 14.32% in the whole population, men and women, respectively. Independent of gender and other CVD risk factors, older age significantly increased the odds of having atrial fibrillation/flutter, complete left bundle branch block, complete right bundle branch block, sinus tachycardia, atrial/junctional/ventricular premature beats, ST depression and T abnormalities, tall R wave left, left/right atrial hypertrophy, left axis deviation and low voltage. Hypertension, overweight, obesity and hypercholesterolemia all independently increased the odds of having ST depression and T abnormalities. History of cardiovascular/cerebrovascular diseases was positively associated with major arrhythmias, ST depression and T abnormalities and tall R wave left. CONCLUSIONS: This study provides estimates of the prevalences of ECG findings in a large population of Chinese adults. Gender, age, CVD risk factors and history of cardiovascular/cerebrovascular diseases were significantly associated with ECG abnormalities.

Distribution and related factors of cardiometabolic disease stage based on body mass index level in Chinese adults-The National Diabetes and Metabolic Disorders Survey.

BACKGROUND: It is important to characterize distribution of cardiometabolic disease (CMD) based on different body mass index (BMI) levels in a population. This information remains scarce in China, so we investigated the proportions and related factors of cardiometabolic disease stages based on different BMI levels in Chinese adults. METHODS: We included 45 093 participants aged ≥20 years from the National Diabetes and Metabolic Disorders Survey. Cardiometabolic disease (central obesity, elevated triglycerides, elevated blood pressure, elevated plasma glucose, reduced high-density lipoprotein cholesterol, and cardiovascular disease) was classified as stage 0 (no CMD), stage 1 (mild-to-moderate CMD), or stage 2 (severe CMD). Overweight/obesity was defined as BMI ≥25 kg/m2 . RESULTS: The standardized proportions of stage 0, stage 1, and stage 2 were 32.6%, 36.4%, and 30.9% in normal-weight men, 29.9%, 42.5%, and 27.7% in normal-weight women, 4.9%, 31.7%, and 63.4% in overweight/obese men, and 6.9%, 31.4%, and 61.7% in overweight/obese women, respectively. Multinomial regression showed that regardless of gender or region, the probability of severe cardiometabolic disease rapidly increased with increasing BMI. Severe cardiometabolic disease risk was positively associated with ageing, family history of diabetes, hypertension, or cardiovascular disease, but was inversely associated with higher levels of education and increased physical activity. CONCLUSIONS: Of Chinese men and women with normal weight, more than one third had mild-to-moderate cardiometabolic disease, and less than one third had severe cardiometabolic disease, while of these with overweight or obesity, nearly one third had mild-to-moderate cardiometabolic disease, and nearly two thirds had severe cardiometabolic disease.

PEI functionalized cell membrane for tumor targeted and glutathione responsive gene delivery.

Polyethylenimine (PEI) is a broadly exploited cationic polymer due to its remarkable gene-loading capacity. However, the high cytotoxicity caused by its high surface charge density has been reported in many cell lines, limiting its application significantly. In this study, two different molecular weights of PEI (PEI10k and PEI25k) were crosslinked with red blood cell membranes (RBCm) via disulfide bonds to form PEI derivatives (RMPs) with lower charge density. Furthermore, the targeting molecule folic acid (FA) molecules were further grafted onto the polymers to obtain FA-modified PEI-RBCm copolymers (FA-RMP25k) with tumor cell targeting and glutathione response. In vitro experiments showed that the FA-RMP25k/DNA complex had satisfactory uptake efficiency in both HeLa and 293T cells, and did not cause significant cytotoxicity. Furthermore, the uptake and transfection efficiency of the FA-RMP25k/DNA complex was significantly higher than that of the PEI25k/DNA complex, indicating that FA grafting can increase transfection efficiency by 15 %. These results suggest that FA-RMP25k may be a promising non-viral gene vector with potential applications in gene therapy.

Cardiovascular disease risk in early-onset vs late-onset type 2 diabetes in China: A population-based cross-sectional study.

BACKGROUND: This study investigated the effects of early-onset type 2 diabetes (EOD) vs late-onset type 2 diabetes (LOD) on nonfatal cardiovascular diseases (CVD) in China. METHODS: We conducted a cross-sectional survey of 46 239 participants from 14 provinces in China from 2007 to 2008, selecting 4949 participants with type 2 diabetes for analysis. Participants were categorized as EOD (<40 years) or LOD (≥40 years) based on age at diabetes diagnosis. Sociodemographic and nonfatal CVD information was collected through an interviewer-assisted questionnaire and clinical examination. Logistic regression analysis was used to investigate the nonfatal CVD risk. RESULTS: Out of 4949 participants with type 2 diabetes, 390 (7.88%) had nonfatal CVD. Participants with EOD had a higher age-standardized prevalence of nonfatal CVD than those with LOD (11.4% vs 4.4%). Compared to LOD patients, EOD patients tended to be males and had a higher family history of diabetes, unhealthy lifestyle behaviors, and lower blood pressure levels. After adjustment for age and sex, EOD patients had a higher risk of nonfatal CVD than LOD patients (odds ratio [OR] 2.3, 95% CI 1.5-3.5). After further adjustment for diabetes duration, use of drugs, and other risk factors, the OR of nonfatal CVD was reduced but significant (OR 1.8, 95% CI 1.1-2.9). Sensitivity analysis revealed that EOD patients with metabolic syndrome had an increased nonfatal CVD risk compared to LOD patients (OR 2.0, 95% CI 1.2-3.5). CONCLUSIONS: EOD patients are at increased risk of nonfatal CVD. Individualized intervention and management measures for EOD patients are necessary.

Serum lipids and lipoproteins in Chinese men and women.

BACKGROUND: Because of rapid change in lifestyle risk factors, cardiovascular disease has become the leading cause of death in China. We sought to estimate the national levels of serum lipids and lipoproteins among the Chinese adult population. METHODS AND RESULTS: We conducted a cross-sectional study in a nationally representative sample of 46 239 adults aged ≥20 years. Fasting serum total, high-density lipoprotein, and low-density lipoprotein cholesterol and triglycerides were measured by standard methods. The age-standardized estimates of total, high-density lipoprotein, and low-density lipoprotein cholesterol and triglycerides were 4.72 (95% confidence interval, 4.70-4.73), 1.30 (1.29-1.30), 2.68 (2.67-2.70), and 1.57 (1.55-1.58) mmol/L, respectively, in the Chinese adult population. In addition, 22.5% (21.8-23.3%) or 220.4 million (212.1-228.8) Chinese adults had borderline high total cholesterol (5.18-6.21 mmol/L), and 9.0% (8.5-9.5%) or 88.1 million (83.4-92.8) had high total cholesterol (≥6.22 mmol/L). The population estimates for borderline high (3.37-4.13 mmol/L), high (4.14-4.91 mmol/L), and very high (≥4.92 mmol/L) low-density lipoprotein cholesterol were 13.9% (13.3-14.5%) or 133.5 million (127.0-140.1), 3.5% (3.3-3.8%) or 33.8 million (31.2-36.5), and 3.0% (2.8-3.3%) or 29.0 million (26.3-31.8) persons, respectively. In addition, 22.3% (21.6-23.1%) or 214.9 million (207.0-222.8) persons had low high-density lipoprotein cholesterol (<1.04 mmol/L). The awareness, treatment, and control of borderline high or high total cholesterol were 11.0%, 5.1%, and 2.8%, respectively, in the Chinese adult population. CONCLUSIONS: Serum total and low-density lipoprotein cholesterol levels were high and increasing in the Chinese population. Without effective intervention, atherosclerotic cardiovascular diseases may soar in the near future in China.

Prevalence of cardiovascular disease risk factor in the Chinese population: the 2007-2008 China National Diabetes and Metabolic Disorders Study.

AIMS: Cardiovascular disease (CVD) is now the most prevalent and debilitating disease affecting the Chinese population. The goal of the present manuscript was to analyse cardiovascular risk factors and the prevalence of non-fatal CVDs from data gathered from the 2007-2008 China National Diabetes and Metabolic Disorders Study. METHODS AND RESULTS: A nationally representative sample of 46 239 adults, 20 years of age or older, was randomly recruited using a multistage stratified design method. Lifestyle factors, diagnosis of CVD, stroke, diabetes, and family history of each subject were collected, and an oral glucose tolerance test or a standard meal test was performed. Various non-fatal CVDs were reported by the subjects. SUDAAN software was used to perform all weighted statistical analyses, with P < 0.05 considered statistically significant. The prevalence of coronary heart disease, stroke, and CVDs was 0.74, 1.07, and 1.78% in males; and 0.51, 0.60, and 1.10% in females, respectively. The presence of CVDs increased with age in both males and females. The prevalence of being overweight or obese, hypertension, dyslipidaemia, or hyperglycaemia was 36.67, 30.09, 67.43, and 26.69% in males; and 29.77, 24.79, 63.98, and 23.62% in females, respectively. In the total sample of 46 239 patients, the prevalence of one subject having 1, 2, 3, or ≥4 of the 5 defined risk factors (i.e. smoking, overweight or obese, hypertension, dyslipidaemia, or hyperglycaemia) was 31.17, 27.38, 17.76, and 10.19%, respectively. Following adjustment for gender and age, the odds ratio of CVDs for those who had 1, 2, 3, or ≥4 risk factors was 2.36, 4.24, 4.88, and 7.22, respectively, when compared with patients with no risk factors. CONCLUSION: Morbidity attributed to the five defined cardiovascular risk factors was high in the Chinese population, with multiple risk factors present in the same individual. Therefore, reasonable prevention strategies should be designed to attenuate the rapid rise in cardiovascular morbidity.

Spectral CT reconstruction via low-rank representation and structure preserving regularization.

Objective:With the development of computed tomography (CT) imaging technology, it is possible to acquire multi-energy data by spectral CT. Being different from conventional CT, the X-ray energy spectrum of spectral CT is cut into several narrow bins which leads to the result that only a part of photon can be collected in each individual energy channel.This can severely degrade the image qualities. To address this problem, we propose a spectral CT reconstruction algorithm based on low-rank representation and structure preserving regularization in this paper.Approach:To make full use of the prior knowledge about both the inter-channel correlation and the sparsity in gradient domain of inner-channel data, this paper combines a low-rank correlation descriptor with a structure extraction operator as priori regularization terms for spectral CT reconstruction. Furthermore, a split-Bregman based iterative algorithm is developed to solve the reconstruction model. Finally, we propose a multi-channel adaptive parameters generation strategy according to CT values of each individual energy channel.Main results: Experimental results on numerical simulations and real mouse data indicate that the proposed algorithm achieves higher accuracy on both reconstruction and material decomposition than the methods based on simultaneous algebraic reconstruction technique (SART), total variation minimization (TVM), total variation with low-rank (LRTV), and spatial-spectral cube matching frame (SSCMF). Compared with SART, our algorithm improves the feature similarity (FSIM) by 40.4% on average for numerical simulation reconstruction, whereas TVM, LRTV, and SSCMF correspond to 26.1%, 28.2%, and 29.5%, respectively.Significance: We outline a multi-channel reconstruction algorithm tailored for spectral CT. The qualitative and quantitative comparisons present a significant improvement of image quality, indicating its promising potential in spectral CT imaging.