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A novel voltage output integrated circuit temperature sensor
WU Xiao-bo, ZHAO Meng-lian, YAN Xiao-lang, YAN Xiao-lang
Journal of Zhejiang University-SCIENCE A (Applied Physics & Engineering), 2002, 3(5): 553-558.
https://doi.org/10.1631/jzus.2002.0553
The novel integrated circuit (IC) temperature sensor presented in this paper works similarly as a two-terminal Zener, has breakdown voltage directly proportional to Kelvin temperature at 10 mV/°C, with typical error of less than ±1.0°C over a temperature range from -50°C to +125°C. In addition to all the features that conventional IC temperature sensors have, the new device also has very low static power dissipation (0.5 mW), low output impedance (less than 1Ω), excellent stability, high reproducibility, and high precision. The sensor\'s circuit design and layout are discussed in detail. Applications of the sensor include almost any type of temperature sensing over the range of -50°C - +125°C. The low impedance and linear output of the device make interfacing the readout or control circuitry especially easy. Due to the excellent performance and low cost of this sensor, more applications of the sensor over wide temperature range are expected.
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Comparison of semivariogram models for Kriging monthly rainfall in eastern China
TANG Yan-bing
Journal of Zhejiang University-SCIENCE A (Applied Physics & Engineering), 2002, 3(5): 584-590.
https://doi.org/10.1631/jzus.2002.0584
An exploratory spatial data analysis method (ESDA) was designed Apr. 28, 2002 for kriging monthly rainfall. Samples were monthly rainfall observed at 61 weather stations in eastern China over the period 1961-1998. Comparison of five semivariogram models (Spherical, Exponential, Linear, Gaussian and Rational Quadratic) indicated that kriging fulfills the objective of finding better ways to estimate interpolation weights and can provide error information for monthly rainfall interpolation. ESDA yielded the three most common forms of experimental semivariogram for monthly rainfall in the area. All five models were appropriate for monthly rainfall interpolation but under different circumstances. Spherical, Exponential and Linear models perform as smoothing interpolator of the data, whereas Gaussian and Rational Quadratic models serve as an exact interpolator. Spherical, Exponential and Linear models tend to underestimate the values. On the contrary, Gaussian and Rational Quadratic models tend to overestimate the values. Since the suitable model for a specific month usually is not unique and each model does not show any bias toward one or more specific months, an ESDA is recommended for a better interpolation result.
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A suppressed gene in integument cells of a fiberless seed mutant in upland cotton
WANG Xue-de, JIANG Shu-li, LI Yue-you, XU Ya-nong
Journal of Zhejiang University-SCIENCE A (Applied Physics & Engineering), 2002, 3(5): 594-599.
https://doi.org/10.1631/jzus.2002.0594
A fiberless seed mutant (fl) was identified in a commercial cotton (Gossypium hirsutum L.) variety Xu-Zhou 142 (FL). This phenotype is associated with lack of fiber cell initiation in the outer integument of the ovule, as was characterized by analysis of genes related to fiber differentiation and development. Two genes, fl-E6 and FL-E6, were cloned from fl-integument cells and FL-fiber or integument cells, respectively. Compared with FL-E6, fl-E6 showed a dramatic change in nucleotide sequence: (1) FL-E6 contained a tandem repetitive sequence in which GGCTCA (Gly-Ser) is repeated five times between the 82nd and the 93rd codon from the first ATG codon, while in fl-E6 the same sequence is repeated four times; (2) The fl-E6 gene encodes a polypeptide of 241 amino acids but lacks two codons between the 90th and 93rd codon and three between the 171st and 174th relative to FL-E6; (3) There are also 12 nucleotide substitutions which would result in 7 amino acid differences between fl-E6 and FL-E6. Analysis of RT-PCR and Northern Blot showed that expression of the fl-E6 gene is suppressed in the fl-integument cells, but highly expressed in FL-fiber cells. The difference between fl-E6 and FL-E6 may be associated with lower expression of fl-E6 in the fl-integument cells. Searches of protein databases with the FL-E6 gene sequence showed similarity to the protein backbones of two arabinogalactan-proteins (AGPs), one from the filtrate of suspension-cultured cells of Pyrus communis (AGPPc2) and the other from Nicotiana alata (AGPNa2). Although the function of the FL-E6 protein in differentiation and development of cotton fiber cells is not known, the data indicate that the mutation of fl-E6 gene from FL-E6 gene may inhibit the fiber cell initiation from epidermal cells of the outer integument of the ovule.
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Effects of light and temperature conditions on flowering in Mat Rush
SHEN Wei-qi, ZHANG Guo-ping, XI Li-feng, GUI Wen-guang
Journal of Zhejiang University-SCIENCE A (Applied Physics & Engineering), 2002, 3(5): 611-616.
https://doi.org/10.1631/jzus.2002.0611
The effects of photoperiod and light intensity on flowering in Mat Rush cv. Gangshan 3 were studied. The results showed that treatments with longer day length stimulated flowering significantly and increased stem flowering percentage (SFP). Plants treated with low light intensity at early stage had substantially reduced florets per cyme, SFP, tillers per plant and stem length. At middle and late stage, low light intensity significantly reduced SFP. The principal climatic factors affecting SFP were as follows: mean temperatures (MT) of the third ten-day period (TDP) in December and of the second TDP in February, actual sunlight hours (SH) of the third TDP in February and precipitation of the third TDP in March. A nonlinear simulation model for SFP was established with experimental results and corresponding climatic data (see Eq.(2)). Simulation by the above equation yielded values the same as those observed from 1992 to 2000, indicating its accuracy in describing the relationship between flowering and light and temperature conditions. The interaction between vernalization and SH is also discussed in this paper.
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Use of flow cytometry to investigate the cytokine response pattern in infants with respiratory syncytial virus infection and bronchiolitis
CHEN Zhi-min, DU Li-zhong, MAO Jian-hua, TANG Yong-min
Journal of Zhejiang University-SCIENCE A (Applied Physics & Engineering), 2002, 3(5): 622-626.
https://doi.org/10.1631/jzus.2002.0622
Objective: To investigate the cytokine response pattern (IL-4/IFN-γ) in infants with RSV infections and bronchiolitis during the acute phase. Methods: Four-color flow cytometry was used to measure intracellular IL-4 and IFN-γ expressions in peripheral blood CD3+ and CD8+ lymphocytes from RSV-infected and bronchiolitis infants. Serum IL-4 and IFN-γ levels were also determined. Results: RSV-infected and bronchiolitis infants showed no statistical differences from not-RSV-infected or pneumonia infants and control in the frequency of IL-4 and IFN-γ expressions in CD3+CD8- lymphocytes, showed no obvious Th1/Th2 imbalance, while IFN-γ was expressed much more frequently in CD3+CD8+ lymphocytes. Systematically, RSV-infected and bronchiolitis infants showed much lower levels of serum IL-4 and IL-4/IFN-γ ratios and much higher serum IFN-γ levels than control. However, there were no statistical differences in the above three indices between RSV-infected and not-RSV infected infants or between bronchiolitis and pneumonia infants, except that bronchiolitis infants had a higher level of serum IFN-γ than pneumonia infants statistically. Conclusions: There is no type-2 cytokine response predominance in the acute phase of RSV infection and bronchiolitis. IL-4 production is suppressed and IFN-γ production upregulated, the latter being most prominent in bronchiolitis infants.
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Study on the serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) in patients with Helicobacter pylori Infection
WU Qin-dong, ZHU Yong-liang, SHI Yi-hai
Journal of Zhejiang University-SCIENCE A (Applied Physics & Engineering), 2002, 3(5): 627-631.
https://doi.org/10.1631/jzus.2002.0627
Objective: To evaluate the interaction between serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) and Helicobacter pylori (H. pylori) infection in patients with chronic gastritis and peptic ulcer. Methods: The serum levels of sICAM-1 in 205 patients with chronic gastric diseases were detected by ELISA method and the status of H. pylori was determined by histologic examination, RUT, 14C - UBT, and serology. The sera obtained from 18 healthy volunteers served as controls. Results: The serum levels of sICAM-1 were significantly higher in patients with H. pylori positive than those of H. pylori negative (889.43±32.52 ng/ml vs. 747.07±30.45 ng/ml, P<0.05). The serum levels of sICAM-1 in patients with mild, moderate and severe infection of H. pylori were 841.68±72.36 ng/ml, 905.43±37.59 ng/ml and 1012.54±49.34 ng/ml, respectively (P<0.05). The serum levels of sICAM-1 proved to be significantly correlated with the density of H. pylori colonization in gastric mucosa (rs=0.316, P<0.001). The serum levels of sICAM-1 in patients with chronic gastritis and peptic ulcer were significantly higher than those in healthy controls (P<0.05). Conclusions: These results indicated that H. pylori infection up-regulates the expression of sICAM-1.
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25 articles
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