Detection of human erythrocytes influenced by iron deficiency anemia and thalassemia using atomic force microscopy

PurposeIron deficiency anemia (IDA) and thalassemia (THAL) are two types of microcytic anemia, and both of these conditions disturb the morphology and function of erythrocytes at the molecular level. The ability to distinguish between thalassemic and iron deficiency anemia microcytosis has important clinical implications. The purpose of this study was to show that pathophysiological changes to erythrocytes could be detected at the nanometer scale, which is important for the early diagnosis of anemia and for distinguishing between IDA and THAL.MethodsBlood samples were taken from six healthy volunteers and six patients with either iron deficiency anemia or thalassemia. Changes in the morphological of erythrocytes were studied at the nanometer level using atomic force microscopy (AFM).ResultsThere were dramatic overall shape and surface membrane deformations of the erythrocytes associated with iron deficiency anemia and thalassemia compared to healthy erythrocytes. Healthy and pathological erythrocytes of iron deficiency anemia and thalassemia could be distinguished by the morphologic parameters of width, length, the ratio of length to width, valley, peak, valley-to-peak, standard deviations, and surface fluctuation. These AFM parameters of erythrocyte morphology differed greatly between iron deficiency anemia and thalassemia.ConclusionAFM was found to be an extremely useful tool for detecting and distinguishing between iron deficiency anemia and thalassemia. Erythrocyte morphology is an important determinant for diagnosing and distinguishing IDA and THAL.     

Direct observation of Sn crystal growth during the lithiation and delithiation processes of SnO(2) nanowires

Tin (Sn) crystal growth on Sn-based anodes in lithium ion batteries is hazardous for reasons such as possible short-circuit failure by Sn whiskers and Sn-catalyzed electrolyte decomposition, but the growth mechanism of Sn crystals during battery cycling is not clear. Here we report different growth mechanisms of Sn crystal during the lithiation and delithiation processes of SnO(2) nanowires revealed by in situ transmission electron microscopy (TEM). Large spherical Sn nanoparticles with sizes of 20-200nm grew instantaneously upon lithiation of a single-crystalline SnO(2) nanowire at large current density (j>20A/cm(2)), which suppressed formation of the Li(x)Sn alloy but promoted agglomeration of Sn atoms. Control experiments of Joule-heating (j≈2400A/cm(2)) the pristine SnO(2) nanowires resulted in melting of the SnO(2) nanowires but not Sn particle growth, indicating that the abnormal Sn particle growth was induced by both chemical reduction (i.e., breaking the SnO(2) lattice to produce Sn atoms) and agglomeration of the Sn atoms assisted by Joule heating. Intriguingly, Sn crystals grew out of the nanowire surface via a different "squeeze-out" mechanism during delithiation of the lithiated SnO(2) nanowires coated with an ultra-thin solid electrolyte LiAlSiO(x) layer. It is attributed to the negative stress gradient generated by the fast Li extraction in the surface region through the Li(+)-conducting LiAlSiO(x) layer. Our previous studies showed that Sn precipitation does not occur in the carbon-coated SnO(2) nanowires, highlighting the effect of nanoengineering on tailoring the electrochemical reaction kinetics to suppress the hazardous Sn whiskers or nanoparticles formation in a lithium ion battery.     

不对称三苯胺-锌酞菁的合成及性能研究

以对氨基酚、对硝基氯苯、8-羟基喹啉、4-硝基邻苯二甲腈以及醋酸锌为主要原料,合成了不对称2(3)-[二(对硝基苯基)氨基苯氧基]-9(10),16(17),23(24)-三(8-喹啉氧)锌酞菁(TQPc).用核磁、红外、元素分析等表征TQPc以及前驱化合物结构,TQPc的电子吸收光谱表现出了强烈的π-π*跃迁现象.利用紫外光谱研究了其N,N-二甲基甲酰胺(DMF)和CH2Cl2溶液的吸收光谱性质,结果表明在DMF中主要以单体的形式存在,浓度在0.223×10-5～2.587×10-5mol/L时,TQPc在CH2Cl2溶液中有二聚体的存在,经计算得到平衡常数为0.24×105L/mol.用循环伏安法研究了TQPc的氧化还原行为,结合差分伏安数据计算了能级结构,LUMO(-1.04 V vs SCE)和HOMO(0.78 V vs SCE)与纳米TiO2导带能级匹配,可作为性能较好的电荷传输材料用于染料敏化太阳能电池.     

质子注入能量对垂直腔面发射激光器的阈值和功率的影响

文章研究了如何兼顾质子注入型垂直腔面发射激光器的功率和阈值性能.从模拟和实验两方面分析了质子注入能量与器件功率和阈值特性的关系.发现注入能量过高时,损伤有源区,降低了功率性能.而能量过低则会减弱对注入电流的限制,增加阈值.计算和实验结果表明,对于文中的器件结构,315 keV的注入能量是合适的.在10μm的注入孔径下获得器件的阈值为4.3 mA,功率为1.7 mW.     

Modal interferometer based on tapering single-mode-multimode-single-mode fiber structure by hydrogen flame

A modal interferometer is experimentally demonstrated based on tapering a single-mode-multimode-singlemode (SMS) fiber structure heated by hydrogen flame.The interference fringe begins to form when tapering length is 19.8 mm,and becomes regular and clear when the tapering length is longer and the tapered waist diameter is smaller.Annealing process is undertaken to achieve a high extension ratio of approximately 17 dB with free spectral range of 1.5 nm when the tapering length is 33 mm and the tapered waist diameter is approximately 5μm.The temperature and axial strain dependences of the tapered SMS structure are characterized,and the measured temperature and strain coefficients are +7 pm/℃and -9.536 pm/με, respectively.     

Friedel-like oscillations from interstitial iron in superconducting Fe(1+y)Te0.62Se0.38

Using polarized and unpolarized neutron scattering, we show that interstitial Fe in superconducting Fe(1+y)Te(1-x)Se(x) induces a magnetic Friedel-like oscillation that diffracts at Q⊥=(1/2 0) and involves >50 neighboring Fe sites. The interstitial >2μ(B) moment is surrounded by compensating ferromagnetic four-spin clusters that may seed double stripe ordering in Fe(1+y)Te. A semimetallic five-band model with (1/2 1/2) Fermi surface nesting and fourfold symmetric superexchange between interstitial Fe and two in-plane nearest neighbors largely accounts for the observed diffraction.     

Unique geometric and electronic structure of CO adsorbed on Ge(100): A DFT study

CO adsorption on the Ge(100) surface has been investigated using a slab model with density functional theory implemented in SIESTA. CO was found to be exclusively adsorbed on the asymmetric dimer with C attaching on the lower Ge dimer atom. The adsorption process is barrierless. The calculated adsorption energy and vibration frequencies are comparable to previous experimental results. The crystal orbital Hamilton analysis showed that the bonding between Ge and CO is mainly attributable to the Ge 4p_z orbital overlapping with C 2 s, or with CO molecular orbitals 3σ and 4σ. The repulsive energy between adsorbed CO molecules is less than 1 kcal/mol. The diffusion barrier of CO on the Ge(100) surface is about 14 kcal/mol.     

光学读出非制冷红外成像技术的光学灵敏度分析

不同于传统的非制冷红外成像技术,提出了基于微电子机械系统(MEMS)的新概念光学读出非制冷红外成像技术。它的光学读出系统基于空间刀口滤波原理,具有高灵敏度、高分辨率和高抗震性等优点,但同时也受到了反光板的弯曲变形、粗糙度等复杂因素的影响。在大量实验数据的基础上,利用夫琅禾费近场衍射理论,建立了复杂因素下光学灵敏度的理论分析模型,详细分析了刀口滤波位置、反光板的长度、曲率半径、粗糙度、LED光源的强度以及扩展宽度等对光学灵敏度的影响,并提出了通过极限操作使系统的光学灵敏度最大化的光学优化方法。     

Effect of thermal treatment on the magnetization processes of nanocrystalline Fe80Ge3Nb10B7 alloys

The dynamic magnetization processes of nanocrystalline Fe₈₀Ge₃Nb₁₀B₇ alloys after annealing at different temperatures are studied through the permeability spectroscopy. Three steps of crystallization are found when amorphous Fe₈₀Ge₃Nb₁₀B₇ alloys are heated from 300to 1200 K. The dominant magnetization process varies with different annealing temperatures. Domain wall bulging is the main magnetization mechanism under weak applied field. When the applied field exceeds pinning field H_p, the depinning-involved domain wall displacement occurs. Different annealing temperature results in different H_p. The lower value of μ′ and high relaxation frequency after heating at 923 and 973 K are due to the strengthened domain wall pinning and the increase of magnetocrystalline anisotropy.     

p-Sulfonated calix[6]arene modified graphene as a 'turn on' fluorescent probe for L-carnitine in living cells

p-Sulfonated calix[6]arene modified graphene has been firstly synthesized and provided as a 'turn on' probe for L-carnitine through monitoring the fluorescence signal both in vitro and in living cells.