Matrix-assisted laser desorption ionization time-of-flight mass spectrometry for identification and antifungal susceptibility of penicillium marneffei

Penicillium marneffei is the most important thermal dimorphic fungus causing systemic mycosis in HIV-infected patients in Southeast Asia. However, laboratory diagnosis based on microscopic morphology and mycelial-to-yeast conversion is time-consuming and expertise-dependent. The performance of the Bruker MALDI-TOF MS system for identification of mold and yeast cultures of 59 P. marneffei strains were evaluated by using the direct transfer method. Using the Bruker databases, BDAL v4.0.0.1 and Filamentous Fungi Library 1.0, the 59 P. marneffei strains grown in mold and yeast phase were identified as P. funiculosum (score 2.0. The spectra of P. marneffei exhibited significant difference to those of the closely related species, P. brevi-compactum, P. chrysogenum, Talaromyces aurantiacus and T. stipitatus (one strain included for each species). P. brevi-compactum was identified to the genus level (as P. brevi-compactum but with score <2.0) and P. chrysogenum was unidentified (as P. chrysogenum but with score <1.7) using the combined database with or without spectra from P. marneffei. Both T. aurantiacus and T. stipitatus were unidentified (as wrong species with score <1.7). MALDI-TOF MS is useful for rapid identification of both yeast and mold cultures of P. marneffei, but this requires expansion of the database using P. marneffei strains. Since the susceptibilities of P. marneffei to the newer antifungal drugs are not well studied, their in vitro antifungal activities against the 59 isolates of P. marneffei were also investigated in accordance with CLSI M27-A3 microdilution method. MICs of itraconazole, voriconazole, posaconazole and anidulafungin for yeast form of P. marneffei were determined. The MICs of itraconazole, voriconazole, posaconazole and anidulafungin were 0.00128-0.00256 μg/ml, 0.01565-0.0625 μg/ml, 0.000978-0.001956 μg/ml, 2-8 μg/ml respectively. The results suggested that the azoles have similarly good activities against P. marneffei, whereas anidulafungin was the least active.published_or_final_versionMicrobiologyMasterMaster of Medical Science

Study on the Estimation Algorithm of the Temperature Based on Mid-Wave Infrared Remote Sensing

高于绝对零度的物体满足Plank定律,因此红外辐射在一定程度上反映温度。红外辐射测温具有响应速度快,分辨率高,能较好的实现对微小、高速移动等不可接触测量目标的温度测量。用一种先进的双波段红外遥感光谱系统采集不同温度金属的红外发射光谱,分析和研究这些不同温度的光谱数据所具有的不同特征。在此基础上,对样本提取重心位置、波峰位置、波长λ1的值、波长λ2的值四种光谱特征,寻找温度与其之间的函数关系;并建立多元线性回归模型,通过光谱反推温度值。实验结果表明,该方法可以有效的分辨有明显温差的高温物体,在实验所测温度范围内的测温绝对误差小于30℃,在测量误差小于20℃的置信区间内有98%正确率,优于一般系统需要保证目标发射率、大气透射率、环境等效辐射温度等复杂参数高精度的情况下2%的测温精度。该方法可以简单有效的对远距离目标测温,从而进一步拓展红外光谱遥测温度的应用领域。Since objects above absolute zero agree with the Plank law,the objects' temperature is reflected by the infrared radiation.With fast response and high resolution,temperature estimation based on mid-wave infrared remote sensing could realize the temperature measurement for small,high-speed and touch-free objects.A new optical system for infrared(IR)image-spectrum integration remote sensing was used to acquire infrared emission spectra from different temperatures of metal.With this basis,we extracted four appropriate spectral features which were the center of gravity position,peak position,the value of wavelengthλ1and the value of wavelengthλ2from the training samples.The relationship between temperature and these features was studied.A multiple linear regression model was established to estimate the temperatures from the spectra.The experimental results showed that,the method could distinguish hot objects with obvious temperature differences.The absolute error was less than 30℃in the experimental temperature range.The accuracy was 98%in the range that the measurement error was less than 20 ℃,which was better than the 2% precision of the general system with the complex strict emissivity,atmospheric transmittance,environmental equivalent radiation temperature and some other parameters.This method could measure the temperature of the remote objects in a simple and effective way,and so could expand the application field of temperature estimation based on infrared remote sensing.中央高校基本科研业务专项资金项目(XMU2013121018);; 国家自然科学基金项目(61404112,61571381);; 福建省自然科学基金项目(2012J01413)资

Preparation of Elastomers from Whole Ground Tire Rubber

［中文文摘］用硫化改性剂和废轮胎胶粉制备了全胶粉弹性体.讨论了改性剂用量、炭黑用量、加工工艺及加工助剂对全胶粉弹性体物理机械性能的影响.实验发现硫化改性剂用量为2份;炭黑用量15份;加工油用量小于2份,可以得到较好性能的全胶粉弹性体,拉伸强度达7.9 MPa,断裂伸长率为315%,超过了再生胶的国标(拉伸强度6 MPa).同时对全胶粉弹性体的微观形貌及断裂行为也进行了讨论.［英文文摘］Ground Tire Rubber(GTR) was reclaimed by using the strong shearing force and the reclaiming agent in less than ten minute.It was found that adding 2 phr reclaiming agent,15 phr carbon black,2 phr naphthenic oil,the obtained elastomer had the best mechanical properties.The tensile strength was 7.9 MPa,elongation at break was 315%,the tear strength was 28 N/m.The microstruture of elastomers were also been detected by SEM

Luminous Performance of Remote Phosphor White LED

研究了高色温和低色温两种球冠状远程荧光粉白光lEd在不同电流、不同热沉温度下的发光性能差异.结果表明:在大电流下,lEd有源层内由于量子限制斯塔克效应使其峰值波长向短波方向移动,偏离了高色温荧光粉的最佳激发波长,更加接近低色温荧光粉的最佳激发波长.高色温lEd的相关色温随电流增加呈上升趋势,低色温lEd的相关色温随电流增加呈下降趋势,与它们的量子效率变化引起的色坐标漂移有很大关系.两种lEd量子效率和发光效能随热沉温度的升高均呈略微增大的趋势;其中,高色温lEd的量子效率和发光效能随电流的增大而减小,而低色温lEd的量子效率和发光效能则随电流的增大而升高;高色温lEd发光性质较低色温lEd好,但色特性的稳定程度不如低色温lEd.The luminous properties of sphere-like remote phosphor white LEDs with high Correlated Color Temperature(CCT)and low CCT were studied under different drive currents and heat sink temperatures.The result shown that the quantum efficiency and luminous efficacy of both LEDs raise with the increase of heat sink temperatures;the high-CCT LED's quantum efficiency and luminous efficacy decrease with rising currents.However,the low-CCT LED shows a reverse trend.The reason is attributed to the quantum confinement stark effect in the active region,which makes the wavelength move towards shortwavelength so as to deviate from the optimum stimulation wavelength of the high-CCT phosphor,but close to the optimum stimulation wavelength of the low-CCT phosphor.The CCT of the high-CCT LED increase with rising currents,again,the low-CCT LED shows a reverse trend with rising currents.This trend is mainly related to the drifting of color coordinates caused by quantum efficiency changing.To sum up,the high-CCT LED possesses better optical properties but inferior color properties than the low-CCT LED.国家自然科学基金(Nos.11104230;61102030); 福建省产学研重大科技项目(Nos.2011H6025;2013H6024); 福建省重点科技项目(No.2012H0039)资

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies