Nonparametric block-structured modeling of rat lung mechanics

The quasistatic and dynamic pressure volume characteristics of the lungs were measured in five anesthetized, paralyzed open-chest rats. Psuedo-random volume perturbations over a frequency range of 0.25 to 25 Hz and having peak-peak amplitudes of 1 to 4 ml were applied after the lungs were allowed to expire against 0.2, 0.4, 0.6, and 0.8 kPa positive endexpiratory pressure (PEEP). The lung mechanics were partitioned in two ways: a linear dynamic block followed by a static nonlinearity (Wiener model) and a static nonlinearity ahead of a linear dynamic block (Hammerstein model). It was found that a Hammerstein model featuring a third-order polynomial static nonlinearity and a linear impulse response function of 1-sec duration accounted for the greatest amount of the output variance (98.8±06%, mean±SD from perturbations of 4 ml amplitude and PEEP-0.8 kPa). The static nonlinear behavior matched the measured quasistantic pressure volume behavior obtained at the same amplitude and at the same level of PEEP, provided that all direct current gain of the model was located within the static nonlinearity. Under these conditions, the linear resistance was inversely dependent on the PEEP, whereas little PEEP or amplitude dependence of the linear compartment elastance was observed. Thus, of the two block-structured models tested, the Hammerstein model accounted better for the large amplitude nonlinear mechanical behavior. However, neither model could account for the dependence of the linear block resistance on PEEP.     

藏药如意珍宝丸的鉴别和含量测定

目的　建立藏药如意珍宝丸的鉴别和含量测定方法。方法　采用薄层色谱法和高效液相色谱法。结果　如意珍宝丸中 ,在荜茇、红花、肉桂、黄葵子、丁香和决明子等药材与对照药材相应的色谱位置处各有相同的斑点 ;并采用HPLC法测定了制剂中诃子的有效成份没食子酸的含量 ,其回归方程为A =6× 10 5C +718 14 (r =0 9998) ,RSD =1 5 8%。结论　所建立的鉴别与含量测定方法简便、准确 ,可用于如意珍宝丸的质量控制。     

脊柱孤立性浆细胞瘤的临床及影像学特点分析

目的：探讨脊柱孤立性浆细胞瘤的临床及影像学特点。方法：分析经手术病理检查证实的6例脊柱孤立性浆细胞瘤病例的临床特点及影像学特征。结果：病椎附近逐渐加重的疼痛是其共同首发临床表现。其X线片多表现为椎体的溶骨性破坏；ECT上表现不一；CT多为椎体骨质的虫嗜状破坏；MRI示病椎信号失均，T1WI低信号，T2WI等或稍高信号，增强扫描有不均匀强化。结论：CT及MRI可明确脊柱孤立性浆细胞瘤的形态特征及病灶范围，其确诊仍需借助骨髓活检或手术标本病理检查。但对颈背部疼痛的患者，早期行MRI检查有助于及时发现病变，避免严重脊柱脊髓损害的出现。     

真菌G-18代谢产物的研究——Ⅱ.免疫抑制剂G-18-Ⅳ的分离鉴别

从多孢木霉(Trichoderma polysporum)的发酵液中,分离到一组具有免疫抑制作用的物质-G-18-Ⅰ、G-18-Ⅱ、G-18-Ⅲ、G-18-Ⅳ,其中G-18-Ⅳ为在红外光谱2100cm~(-1)具有强吸收的异腈类化合物,基于理化性质及光谱数据,已鉴别G-18-Ⅳ为异腈素酸E(木菌素)甲酯。     

心率与血压变异性的多变量、多维信号分析进展

心率变异性与血压变异性反映心血管系统自主神经的调制活动，近年研究已向多变量、多维、动态分析方向发展。心率与血压变异性的多变量系统辨识、时频分析及非线性动力学分析等技术方法，将在心血管疾病的危险性预报、病情评估、疗效评价及特种环境医学等领域有更多应用。     

Automated identification of ERP peaks through Dynamic Time Warping: An application to developmental dyslexia

ObjectiveThis article proposes a method to automatically identify and label event-related potential (ERP) components with high accuracy and precision.MethodsWe present a framework, referred to as peak-picking Dynamic Time Warping (ppDTW), where a priori knowledge about the ERPs under investigation is used to define a reference signal. We developed a combination of peak-picking and Dynamic Time Warping (DTW) that makes the temporal intervals for peak-picking adaptive on the basis of the morphology of the data. We tested the procedure on experimental data recorded from a control group and from children diagnosed with developmental dyslexia.ResultsWe compared our results with the traditional peak-picking. We demonstrated that our method achieves better performance than peak-picking, with an overall precision, recall and F-score of 93%, 86% and 89%, respectively, versus 93%, 80% and 85% achieved by peak-picking.ConclusionWe showed that our hybrid method outperforms peak-picking, when dealing with data involving several peaks of interest.SignificanceThe proposed method can reliably identify and label ERP components in challenging event-related recordings, thus assisting the clinician in an objective assessment of amplitudes and latencies of peaks of clinical interest.     

The Pattern of Development from Non-communicative Behaviour to Language by Hearing Impaired and Hearing Infants

This article reports a longitudinal study of the communicative and linguistic development of five infants, identified as having severe or profound bilateral sensorineural hearing loss, and using amplification consistently, by 3-6 months of age. Each hearing impaired infant was carefully matched for chronolgical age, social and cultural background with a normally hearing infant. The parents of each of the infants had normal hearing and spoken English was the first language of the home. Video recorded social interaction took place over a variety of semi-structured contexts and occurred at six-weekly intervals from 6 to 21 months. The pattern of gestural and vocal communication and the transition to symbolic language by each hearing impaired and hearing infant forms the focus of this report. It is concluded that severely and profoundly hearing impaired infants can follow a normal pattern of communicative and linguistic development (albeit sometimes delayed) when hearing impairment is identified within the first months of life and appropriate interventions are in place.     

A comparison of six deconvolution techniques

We present results for the comparison of six deconvolution techniques. The methods we consider are based on Fourier transforms, system identification, constrained optimization, the use of cubic spline basis functions, maximum entropy, and a genetic algorithm. We compare the performance of these techniques by applying them to simulated noisy data, in order to extract an input function when the unit impulse response is known. The simulated data are generated by convolving the known impulse response with each of five different input functions, and then adding noise of constant coefficient of variation. Each algorithm was tested on 500 data sets, and we define error measures in order to compare the performance of the different methods. The work described in this paper was carried out as part of Grant GR/J67130 “Identifiability and Indistinguishability of Nonlinear Dynamic Systems” from the U.K. Engineering and Physical Sciences Research Council.     

The validation of a 7-locus multiplex STIR test for use in forensic casework

We have evaluated a multiplex STR system for routine forensic use, which co-amplifies six short tandem repeat (STR) loci; HUMTH01, D21S11, D18S51, D8S1179, HUMVWF31/A and HUMFIBRA (FGA), in conjunction with the X-Y homologous gene Amelogenin. Analysis of PCR products employs denaturing polyacrylamide gels coupled with fluorescentlabelled primers and detection is undertaken on ABD 373A automated sequencers. The technique was shown to be robust and reproducible when samples were analysed under conditions consistent with those encountered in a forensic environment.The system was demonstrated to be human specific and is suitable for use with both aged and degraded material. Somatic stability was proven with a wide range of tissue types and we were able to detect mixtures at ratios between 1:10 and 10: 1. During this study no incidence of sample mis-typing due to allelic or locus drop-out was observed. Furthermore, although additional artefact bands were occasionally encountered these did not interfere with the interpretation of results. The performance of the system with poor quality samples demonstrated its suitability as a powerful tool in forensic investigation.