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Prevalence of vitamin D deficiency in girls with idiopathic central precocious puberty

null

《医学前沿（英文）》 2018年 第12卷 第2期   页码 174-181 doi: 10.1007/s11684-017-0544-5

摘要：

The relationship between vitamin D deficiency and idiopathic central precocious puberty (ICPP) has been recently documented. In this study, 280 girls diagnosed with ICPP and 188 normal puberty control girls of similar ages were enrolled and retrospectively studied. The ICPP group had significantly lower serum 25-hydroxyvitamin D (25[OH]D) levels than the control group. Furthermore, a nonlinear relationship was found between serum 25[OH]D and ICPP, and a cut-off point for serum 25[OH]D was found at 31.8 ng/ml for ICPP with and without adjusting the different confounding factors. Girls with serum 25[OH]D≥31.8 ng/ml had a lower odds ratio (unadjusted: OR 0.36, 95% CI 0.15 to 0.83, <0.05; height and weight adjusted: OR 0.44, 95% CI 0.18 to 1.08, = 0.072; BMI adjusted: OR 0.36, 95% CI 0.16 to 0.84, <0.05). The ICPP subjects with 25[OH]D deficiency had a higher body mass index (BMI) than the subjects from the two other subgroups. Correlation analysis showed that vitamin D level is correlated with BMI and some metabolic parameters in the ICPP group. Our study suggested that vitamin D status may be associated with ICPP risk and may have a threshold effect on ICPP.

关键词： idiopathic central precocious puberty     threshold effects     vitamin D status    

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THE ANTHOCYANIN BIOSYNTHETIC REGULATOR MDMYB1 POSITIVELY REGULATES ASCORBIC ACID BIOSYNTHESIS IN APPLE

Jianping AN, Xiaofei WANG, Chunxiang YOU, Yujin HAO

《农业科学与工程前沿（英文）》   页码 231-235 doi: 10.15302/J-FASE-2020367

摘要： Ascorbic acid (AsA, vitamin C) is involved in the regulation of many aspects of plant growth and development. It is an essential micronutrient for humans and can prevent scurvy, maintain the health of gums and blood vessels, reduce the level of plasma cholesterol and enhance the immune systen. Apple cultivars Orin and Guanghui were crossed to obtain a group of hybrid offspring with and without red flesh in the course of assessing apple germplasm resources. Unexpectedly, the red-flesh apples had higher AsA contents than other apples. Further studies showed that the anthocyanin biosynthetic regulator MdMYB1 directly activates the expression of dehydroascorbate reductase gene , thus promoting the activity of the DHAR enzyme and the accumulation of AsA. This finding reveals the mechanism leading to high AsA levels in red-flesh apples and suggests a new idea to cultivate red-flesh apples with high AsA contents and produce AsA efficiently and without pollution.

关键词： anthocyanin     apples     ascorbic acid     MdMYB1     vitamin C    

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Identification of transporter proteins for PQQ-secretion pathways by transcriptomics and proteomics analysis in

Hui Wan,Yu Xia,Jianghua Li,Zhen Kang,Jingwen Zhou

《化学科学与工程前沿（英文）》 2017年 第11卷 第1期   页码 72-88 doi: 10.1007/s11705-016-1580-4

摘要： Pyrroloquinoline quinone (PQQ) plays a significant role as a redox cofactor in combination with dehydrogenases in bacteria. These dehydrogenases play key roles in the oxidation of important substrates for the biotechnology industry, such as vitamin C production. While biosynthesis of PQQ genes has been widely studied, PQQ-transport mechanisms remain unclear. Herein, we used both two-dimensional fluorescence-difference gel electrophoresis tandem mass spectrometry and RNA sequencing to investigate the effects of overexpression in an industrial strain of WSH-003. We have identified 73 differentially expressed proteins and 99 differentially expressed genes, a majority of which are related to oxidation-reduction and transport processes by gene ontology analysis. We also described several putative candidate effectors that responded to increased PQQ levels resulting from overexpression. Furthermore, quantitative PCR was used to verify five putative PQQ-transport genes among different PQQ producing strains, and the results showed that , and were upregulated in all conditions. Then the three genes were over-expressed in WSH-003 and PQQ production were detected. The results showed that extracellular PQQ of B932_1930 (a transporter) and B932_2186 (an ABC transporter permease) overexpression strains were enhanced by 1.77-fold and 1.67-fold, respectively. The results suggest that the proteins encoded by PqqB, B932_1930 and B932_2186 might enhance the PQQ secretion process.

关键词： 2D-DIGE     pqqB     pyrroloquinoline quinone     RNA-Seq     Vitamin C    

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An Eight-Step Continuous-Flow Total Synthesis of Vitamin B1

Meifen Jiang,Minjie Liu,Weijian Li,Yingqi Xia,Fener Chen,

《工程（英文）》 doi: 10.1016/j.eng.2023.01.016

摘要： Vitamin B1 is widely applied in the healthcare and food industry as an antineuritic and antioxidant to maintain the normal functioning of nerve conduction, the heart, and the gastrointestinal tract. This study reports on an integrated eight-step continuous-flow synthesis of vitamin B1 from commercially available 2-cyanoacetamide. The proposed continuous-flow process is based on advances in chemistry, engineering, and equipment design, and affords improved performance and safety compared with batch-mode manufacturing. Several challenges were precisely investigated and controlled, including mixing, unexpected clogging, solvent switches, an exothermic reaction, and the prevention of side reactions, using various micro-channel flow reactors, mixers, separators, and continuous filters. Vitamin B1 was produced with a separated yield of 47.7% and high purity, with a total residence time of about 3.5 h. This eight-step continuous-flow protocol enables technology involving up to six of the key principles of green chemistry. Hence, the application of flow technology is of paramount importance for improving security, reducing waste, and, in particular, improving the efficiency of batch operations that require several days for manufacturing.

关键词： Vitamin B1     Continuous-flow synthesis     Micro-reactor     Continuous manufacturing    

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Valveless pumping using a two-stage impedance pump

C.-C. LEE, Y. A. ABAKR, K.-C. WOO

《机械工程前沿（英文）》 2013年 第8卷 第3期   页码 311-318 doi: 10.1007/s11465-013-0270-x

摘要：

Impedance pump is defined as a type of valveless pumping mechanism, where an elastic tube is joined with a tube of different impedance, a periodic asymmetrical compression on part of the elastic tube will produce a unidirectional flow. Numerical and experimental studies had been conducted in the past, but little experimental work was found to exploit the principle of multi-stage impedance pumping for fluid transportation. This paper concentrates on the fluid behavior for an open-loop two-stage system experimentally. The aim of this work is to have an insight on the deliverable head and pumping rate of an open-loop two-stage impedance pumping system. This paper generally investigates the effect of different parameters towards the generation of unidirectional flows and composite flow of two opposite directions. Results obtained are of significant values.

关键词： valveless pumping     open-loop     two-stage     unidirectional     composite    

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Bioinspired C/TiO

Jian LI, Likun GAO, Wentao GAN

《农业科学与工程前沿（英文）》 2017年 第4卷 第4期   页码 459-464 doi: 10.15302/J-FASE-2017178

摘要： butterfly wings were replicated by a sol-gel method and a calcination process, which could take advantage of the spatial features of the wing to enhance their photocatalytic properties. Hierarchical structures of -carbon-TiO (PP-C-TiO ) were confirmed by SEM observations. By applying the Brunauer-Emmett-Teller method, it was concluded that in the presence of wings the product shows higher surface area with respect to the pure TiO made in the absence of the wings. The higher specific surface area is also beneficial for the improvement of photocatalytic property. Furthermore, the conduction and valence bands of the PP-C-TiO are more negative than the corresponding bands of pure TiO , allowing the electrons to migrate from the valence band to the conduction band upon absorbing visible light. That is, the presence of C originating from wings in the PP-C-TiO could extend the photoresponsiveness to visible light. This strategy provides a simple method to fabricate a high-performance photocatalyst, which enables the simultaneous control of the morphology and carbon element doping.

关键词： bioinspired     butterfly wings     C/TiO2     photocatalyst     visible light    

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基于S3C2410的GPRS数据终端的设计

孙学用

《中国工程科学》 2007年 第9卷 第12期   页码 94-96

摘要： 提出了以S3C2410处理器为核心，以SIM100-E为GPRS通信模块,构建了一套嵌入式Internet数据终端的方案，对其硬件构成及工作流程进行了讨论，描述了其软件层次结构，并详细讲解了基于该平台的

关键词： GPRS；嵌入式Internet；S3C2410；SIM100-E    

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Antithrombin deficiency and decreased protein C activity in a young man with venous thromboembolism:

null

《医学前沿（英文）》 2018年 第12卷 第3期   页码 319-323 doi: 10.1007/s11684-017-0553-4

摘要：

Antithrombin and protein C are two crucial members in the anticoagulant system and play important roles in hemostasis. Mutations in and lead to deficiency or dysfunction of the two proteins, which could result in venous thromboembolism (VTE). Here, we report a Chinese 22-year-old young man who developed recurrent and serious VTE in cerebral veins, visceral veins, and deep veins of the lower extremity. Laboratory tests and direct sequencing of and were conducted for the patient and his family members. Coagulation tests revealed that the patient presented type I antithrombin deficiency combined with decreased protein C activity resulting from a small insertion mutation c.848_849insGATGT in and a short deletion variant c.572_574delAGA in . This combination of the two mutations was absent in 400 healthy subjects each from southern and northern China. Then, we summarized all the mutations of the and gene reported in the Chinese Han population. This study demonstrates that the combination of antithrombin deficiency and decreased protein C activity can result in severe VTE and that the coexistence of different genetic factors may increase the risk of VTE.

关键词： antithrombin deficiency     protein C activity     mutation     variant     venous thromboembolism     anticoagulants    

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Atomistic simulations of plasma catalytic processes

Erik C. Neyts

《化学科学与工程前沿（英文）》 2018年 第12卷 第1期   页码 145-154 doi: 10.1007/s11705-017-1674-7

摘要： There is currently a growing interest in the realisation and optimization of hybrid plasma/catalyst systems for a multitude of applications, ranging from nanotechnology to environmental chemistry. In spite of this interest, there is, however, a lack in fundamental understanding of the underlying processes in such systems. While a lot of experimental research is already being carried out to gain this understanding, only recently the first simulations have appeared in the literature. In this contribution, an overview is presented on atomic scale simulations of plasma catalytic processes as carried out in our group. In particular, this contribution focusses on plasma-assisted catalyzed carbon nanostructure growth, and plasma catalysis for greenhouse gas conversion. Attention is paid to what can routinely be done, and where challenges persist.

关键词： atomic scale simulation     plasma-catalyst    

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Elevated C-reactive protein levels predict worsening prognosis in Chinese patients with first-onset stroke

Jiangtao YAN, Rutai HUI, Daowen WANG

《医学前沿（英文）》 2009年 第3卷 第1期   页码 30-35 doi: 10.1007/s11684-009-0005-x

摘要： The role of high sensitivity C-reactive protein (hsCRP) in predicting prognosis after stroke in the Asian population has not been investigated. We hypothesized that elevated levels of hsCRP were associated with worsening prognosis after stroke in Chinese patients. Two hundred and ninety consecutive patients with first-onset stroke and 290 age- and gender-matched control subjects without any cerebrovascular disease were enrolled for study. Plasma hsCRP level was detected and subsequent vascular events and death were recorded in both groups over a 5-year period. Compared to control group, patients presenting with stroke had higher plasma hsCRP level (3.3 ± 3.8 1.3 ± 2.2 mg/L, < 0.01). Furthermore, in the group of patients with stroke, the mean plasma hsCRP level was higher in patients who developed subsequent vascular diseases or died as compared with the patients without further complications (4.4 ± 4.3 2.7 ± 3.3 mg/L, < 0.01). Compared to the lowest tertile of hsCRP level, the relative risk for vascular events or death in stroke patients was 2.91 in the highest tertile of hsCRP (95% CI, 1.54–5.50, = 0.001). This increase in relative risk for vascular events or death in stroke patients continued after adjustment for age, sex and other cardiovascular risk factors such as hypertension and diabetes ( : 2.771, 95% CI: 1.367–5.617, = 0.005). These findings indicate that increased hsCRP level is associated with worsening prognosis after stroke in Chinese patients and suggests that inflammation is correlated with stroke outcome.

关键词： C-reactive protein     inflammation     stroke    

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A simple, azulene-based colorimetric probe for the detection of nitrite in water

Lloyd C. Murfin, Carlos M. López-Alled, Adam C. Sedgwick, Jannis Wenk, Tony D. James, Simon E. Lewis

《化学科学与工程前沿（英文）》 2020年 第14卷 第1期   页码 90-96 doi: 10.1007/s11705-019-1790-7

摘要： We describe the synthesis and evaluation of an azulene-based chemodosimeter for nitrite. The probe was found to undergo two distinct color changes upon introduction aqueous nitrite ion. A near-instant formation of a grey color provides a qualitative indication of the presence of nitrite, followed by the formation of a deep-yellow/orange color, the endpoint from which quantitative data can be derived. The azulene probe exhibits 1:1 stoichiometry of reaction with nitrite in water, and is selective for nitrite over other anions. The azulene probe was applied to determine nitrite content in cured meat, and compared with the British Standard testing procedure (Griess test). The value obtained from the azulene-based probe agreed closely with the standard test. Our procedure only requires the preparation of one standard solution, instead of the three required for the standard Griess test.

关键词： azulene     nitrite     diazoquinone    

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Comments on the special issue on tropical crops of

Luiz J C B CARVALHO

《农业科学与工程前沿（英文）》 2016年 第3卷 第4期   页码 375-376 doi: 10.15302/J-FASE-2016129

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Comments on the special issue of

Neil C. TURNER

《农业科学与工程前沿（英文）》 2017年 第4卷 第2期   页码 254-255 doi: 10.15302/J-FASE-2017156

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Enhancing the efficiency of nitrogen removing bacterial population to a wide range of C:N ratio (1.5:1 to 14:1) for simultaneous C & N removal

《环境科学与工程前沿（英文）》 2022年 第16卷 第8期 doi: 10.1007/s11783-022-1522-y

摘要：

• Simultaneous C & N removal in Methammox occurs at wide C:N ratio.

关键词： Methanogens     Biological Nitrogen Removal (BNR)     Simultaneous     Methammox     C:N ratio    

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Uncertainty propagation analysis by an extended sparse grid technique

JIA, C. JIANG, C. M. FU, B. Y. NI, C. S. WANG, M. H. PING

《机械工程前沿（英文）》 2019年 第14卷 第1期   页码 33-46 doi: 10.1007/s11465-018-0514-x

摘要： In this paper, an uncertainty propagation analysis method is developed based on an extended sparse grid technique and maximum entropy principle, aiming at improving the solving accuracy of the high-order moments and hence the fitting accuracy of the probability density function (PDF) of the system response. The proposed method incorporates the extended Gauss integration into the uncertainty propagation analysis. Moreover, assisted by the Rosenblatt transformation, the various types of extended integration points are transformed into the extended Gauss-Hermite integration points, which makes the method suitable for any type of continuous distribution. Subsequently, within the sparse grid numerical integration framework, the statistical moments of the system response are obtained based on the transformed points. Furthermore, based on the maximum entropy principle, the obtained first four-order statistical moments are used to fit the PDF of the system response. Finally, three numerical examples are investigated to demonstrate the effectiveness of the proposed method, which includes two mathematical problems with explicit expressions and an engineering application with a black-box model.

关键词： uncertainty propagation analysis     extended sparse grid     maximum entropy principle     extended Gauss integration     Rosenblatt transformation     high-order moments analysis    

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标题 作者 时间 类型 操作

Prevalence of vitamin D deficiency in girls with idiopathic central precocious puberty

null

期刊论文

THE ANTHOCYANIN BIOSYNTHETIC REGULATOR MDMYB1 POSITIVELY REGULATES ASCORBIC ACID BIOSYNTHESIS IN APPLE

Jianping AN, Xiaofei WANG, Chunxiang YOU, Yujin HAO

期刊论文

Identification of transporter proteins for PQQ-secretion pathways by transcriptomics and proteomics analysis in

Hui Wan,Yu Xia,Jianghua Li,Zhen Kang,Jingwen Zhou

期刊论文

An Eight-Step Continuous-Flow Total Synthesis of Vitamin B1

Meifen Jiang,Minjie Liu,Weijian Li,Yingqi Xia,Fener Chen,

期刊论文

Valveless pumping using a two-stage impedance pump

C.-C. LEE, Y. A. ABAKR, K.-C. WOO

期刊论文

Bioinspired C/TiO

Jian LI, Likun GAO, Wentao GAN

期刊论文

基于S3C2410的GPRS数据终端的设计

孙学用

期刊论文

Antithrombin deficiency and decreased protein C activity in a young man with venous thromboembolism:

null

期刊论文

Atomistic simulations of plasma catalytic processes

Erik C. Neyts

期刊论文

Elevated C-reactive protein levels predict worsening prognosis in Chinese patients with first-onset stroke

Jiangtao YAN, Rutai HUI, Daowen WANG

期刊论文

A simple, azulene-based colorimetric probe for the detection of nitrite in water

Lloyd C. Murfin, Carlos M. López-Alled, Adam C. Sedgwick, Jannis Wenk, Tony D. James, Simon E. Lewis

期刊论文

Comments on the special issue on tropical crops of

Luiz J C B CARVALHO

期刊论文

Comments on the special issue of

Neil C. TURNER

期刊论文

Enhancing the efficiency of nitrogen removing bacterial population to a wide range of C:N ratio (1.5:1 to 14:1) for simultaneous C & N removal

期刊论文

Uncertainty propagation analysis by an extended sparse grid technique

JIA, C. JIANG, C. M. FU, B. Y. NI, C. S. WANG, M. H. PING

期刊论文