顺态诱发耳声发射在新生儿听力筛查中的应用

目的评价顺态诱发耳声发射在新生儿听力筛查中应用的重要性、可行性,了解新生儿听力损失的发病状况,以便早期干预。方法应用顺态诱发耳声发射对2915例新生儿进行听力初筛、复筛,外周听力在刺激频率范围内正常表示筛查通过。初筛未通过行复筛,复筛未通过者采用听觉脑干诱发电位技术诊断。结果2915例中初筛通过2587例,需要复筛328例,实际复筛298例,通过286例;确诊为听力损失4例(7耳),新生儿先天性听力损失在筛查儿中发病率为1.37‰。结论应用顺态诱发耳声发射可及早发现新生儿听力损失,并进行及早干预,促进婴幼儿语言发育。

蒸汽压缩制冷系统的稳态和瞬态建模分析

针对蒸汽压缩制冷系统工作过程的分析,建立了蒸汽压缩系统的瞬态和稳态数学模型,对整个蒸汽制冷系统的内部结构开展了深入的研究,并对其组成结构中的相关单元模块进行了建模与分析,在此基础上给出了制冷系统详细的瞬态和稳态的数学模型描述形式,通过对模型的仿真与测试给出了制冷系统工作过程中主要参数的变化情况,尤其是仿真结果与实际系统的工作过程进行对比,验证后表明本文所建立的工作模型,其COP性能与实测的结果误差不超过5%。

浅谈新生儿听力筛查的结果观察

在我国聋儿的患病人数居五大残疾之首,婴幼儿听力损失,直接影响其语言的形成,轻者表现为发音不清,重者表现为聋哑,因此,直接影响他们上学,就业等影响他们的身心健康,有可能一部分导致智力发育障碍.因此为降低聋儿的发病率,加强耳病的防治,应对所有的婴幼儿和新生儿的听力,进行早期听力检测和干预,使聋儿的发病率降到最低水平,使听力损失儿童听力水平有所提高.我们医院在北京市耳科研究所的指导下,应用耳声发射技术,自2002年5月以来,对在本院出生的新生儿进行了常规听力筛查.

当代声乐教学“逆反心理”的思考

所谓教,就是传道、授业、解惑;所谓学,就是要经历领知、解惑、稳固、实际应用几个过程,演唱教学也是如此。演唱教学的整个过程包括了心理。心理教学分为了“顺态”和“逆态”。大多状况下,演唱教学的过程是顺利的,师生配合的暗相契合,呈现的结果理想,还有一种情况是在实际的演唱中,沟通不好,出现了逆态,造成学生逆反心理的产生。

Dynamic Resonant Frequency Bands of Suspension System of Vehicles with Varying Speeds Based on Time⁃Frequency Spectrum

The dynamic responses of suspension system of a vehicle travelling at varying speeds are generally nonstationary random processes,and the non-stationary random analysis has become an important and complex problem in vehicle ride dynamics in the past few years.This paper proposes a new concept,called dynamic frequency domain(DFD),based on the fact that the human body holds different sensitivities to vibrations at different frequencies,and applies this concept to the dynamic assessment on non-stationary vehicles.The study mainly includes two parts,the first is the input numerical calculation of the front and the rear wheels,and the second is the dynamical response analysis of suspension system subjected to non-stationary random excitations.Precise time integration method is used to obtain the vertical acceleration of suspension barycenter and the pitching angular acceleration,both root mean square(RMS)values of which are illustrated in different accelerating cases.The results show that RMS values of non-stationary random excitations are functions of time and increase as the speed increases at the same time.The DFD of vertical acceleration is finally analyzed using time-frequency analysis technique,and the conclusion is obviously that the DFD has a trend to the low frequency region,which would be significant reference for active suspension design under complex driving conditions.

Detoxification of chromium-containing slag by Achromobacter sp.CH-1 and selective recovery of chromium

Based on the principle of bacterial leaching and bacterial metallurgy,a novel technology for the detoxification of chromium-containing slag by Achromobacter sp.CH-1 and chromium recovery was proposed.Strain CH-1 cell morphology before and after Cr(Ⅵ) reduction was observed with a scanning electron microscope(SEM),and the reduction product is found to adhere to terminals of CH-1 cells.Energy-dispersive X-ray(EDX) and electron paramagnetic resonance(EPR) analyses reveal that the main component of the reduction product is Cr(Ⅲ).Furthermore,small and large-scale demonstration projects reveal that Achromobacter sp.can be used to detoxify chromium-containing slag and to selectively recover chromium by using this novel technique.Chromium recovery rate increases with decreasing particle sizes of chromium-containing slag and slagheap height.Chromium recovery rates in 10 t/batch and 20 t/batch of on-site demonstration projects for chromium-containing slag detoxification are more than 90%.

An Extended Model for Coexistence of Superconductivity and Paramagnetism in High-T_c Superconductors

In the present work, the total magnetization in superconducting state is separated into critical state and paramagnetic components in terms of an H（x）-dependent magnetic flux density. Utilizing this model, we reproduce successfully M-H curves measured by Sandu et al. [Phys. Rev. B 74 （2006） 184511] and Sandu et al. [J. Supercond. Incorp. Novel Magn. 17 （2004） 701] for different forms of Jc.

Efficient Quantum Secure Communication Protocol by Rearranging Particle Orders

We propose a quantum secure communication protocol by using three-particle GHZ states. In this protocol, we utilize the ideas of the rearranging orders and the sequence transmission. The sender of messages, Alice, first disturbs the particle orders in an initial sequence, and then sends the sequence of the disturbed orders to the receiver of messages, Bob. Under Alice＇s introduction, Bob rearranges the sequence back to the initial sequence. By making a GHZ state measurement on each of the three particles in turn, Bob can attain Alice＇s secret messages. In addition, we still calculate the efficiency of our three-particle GHZ protocol and generalize it to the case using multi-particle GHZ state.

Labeling of cynomolgus monkey bone marrow-derived mesenchymal stem cells for cell tracking by multimodality imaging

Recently,transplantation of allogeneic and autologous cells has been used for regenerative medicine.A critical issue is monitoring migration and homing of transplanted cells,as well as engraftment efficiency and functional capability in vivo.Monitoring of superparamagnetic iron oxide(SPIO) particles by magnetic resonance imaging(MRI) has been used in animal models and clinical settings to track labeled cells.A major limitation of MRI is that the signals do not show biological characteristics of transplanted cells in vivo.Bone marrow mesenchymal stem cells(MSCs) have been extensively investigated for their various therapeutic properties,and exhibit the potential to differentiate into cells of diverse lineages.In this study,cynomolgus monkey MSCs(cMSCs) were labeled with Molday ION Rhodamine-BTM(MIRB),a new SPIO agent,to investigate and characterize the biophysical and MRI properties of labeled cMSCs in vitro and in vivo.The results indicate that MIRB is biocompatible and useful for cMSCs labeling and cell tracking by multimodality imaging.Our method is helpful for detection of transplanted stem cells in vivo,which is required for understanding mechanisms of cell therapy.