QuickCheck检测加速器的能力测试与评估

目的：在改变测量条件和标准条件的情况下进行测量，对比测量结果，检测QuickCheck的性能，为加速器的晨检及检测结果判读提供依据。方法：通过改变输出剂量、射野大小、SSD、准直器角度和机架角，评估QuickCheck的检测能力。QuickCheck检测的射野参数与三维水箱等测量进行对比。结果：输出剂量增大1 cGy或减小6 cGy，射野改变≥0.2 cm；SSD减小2 cm或增大1 cm，准直器旋转≥2 o，机架角旋转≥6 o，检测结果超过阈值。与三维水箱测量的结果相比，平坦度、对称性（G/T）和（L/R）及剂量率分别相差3.84%、0.67%、0.47%，1.2 MU/min。结论：QuickCheck在检测输出剂量、射野大小、准直器角度、平坦度、对称性及剂量率方面准确度很高，能够满足日常加速器质量保证的需要。在检测SSD、机架角偏差方面能力较弱。     

硫化氢对肝硬化大鼠肝脏survivin表达的影响

目的:探讨抗凋亡因子存活素(survivin)在硫化氢(hydrogen sulfide,H2S)干扰的肝硬化大鼠肝脏中的表达量,了解H2S在肝硬化过程中可能的作用机制.方法:♀SD大鼠经复合因素法复制肝硬化模型,造模结束后随机分为S组、P组、C组,分别腹腔注射硫氢化钠(sodium hydrogen sulfide,NaSH)56mg/(kgd)、炔丙基甘氨酸(Propargylglycine,PPG)30mg/(kgd)及等量生理盐水,用敏感硫电极法检测肝硬化大鼠门静脉中H2S的量,用免疫组织化学及realtime-PCR检测大鼠肝脏survivin蛋白及mRNA表达.结果:S组、P组与C组相比,门静脉血浆内H2S浓度显著改变(51.19mol/L±8.75mol/L,68.97mol/L±2.69mol/Lvs134.49mol/L±12.25mol/L,P<0.05),肝硬化H2S增加组大鼠survivin蛋白及mRNA表达显著增加(P<0.05),肝硬化大鼠体内H2S与survivin表达有相关性.结论:在大鼠肝硬化模型中,随着体内H2S浓度的变化,survivin蛋白及mRNA表达发生变化,这可能是H2S调节肝硬化作用过程中的机制之一.     

Objective assessment of movement competence in children using wearable sensors: An instrumented version of the TGMD-2 locomotor subtest

Movement competence (MC) is defined as the development of sufficient skill to assure successful performance in different physical activities. Monitoring children MC during maturation is fundamental to detect early minor delays and define effective intervention. To this purpose, several MC assessment batteries are available. When evaluating movement strategies, with the aim of identifying specific skill components that may need improving, widespread MC assessment is limited by high time consumption for scoring and the need for trained operators to ensure reliability. This work aims to facilitate and support the assessment by designing, implementing and validating an instrumented version of the TGMD-2 locomotor subtest based on Inertial Measurement Units (IMUs) to quantify MC in children rapidly and objectively. 45 typically developing children, aged 6–10, performed the TGMD-2 locomotor subtest (six skills). During the tests, children wore five IMUs mounted on lower back, on ankles and on wrists. Sensor and video recordings of the tests were collected. Three expert evaluators performed the standard assessment of TGMD-2. Using theoretical and modelling approaches, algorithms were implemented to automatically score children tests based on IMUs’ data. The automatic assessment, compared to the standard one, showed an agreement higher than 87% on average on the entire group for each skill and a reduction of time for scoring from 15 to 2 min per participant. Results support the use of IMUs for MC assessment: this approach will allow improving the usability of MC assessment, supporting objectively evaluator decisions and reducing time requirement for the evaluation of large groups.     

Transport Mobility for Children and Adolescents with Cerebral Palsy (CP)

Background: The transport mobility of children and adolescents with cerebral palsy (CP) is of vital interest for the individual, as well as for society. Enhanced transport mobility can be related to improved functional health status and a higher degree of autonomy, which in turn may reduce the demand for societal support. UN Resolution 48/96, together with Swedish legislation and ''Vision Zero'' have in different ways established that the transport system must be designed to meet also the needs of children and adolescents with disabilities. Hence, it is necessary to identify and eliminate obstacles hindering children and adolescents with CP from using public transport and other means of transport, such as their own cars, at the same level as other members of society. However, in the case of children and adolescents with CP, the transport situation and the learner driver's educational situation have so far been largely unknown. Aim: The general aim of the thesis was to describe and analyse, from a legislative and a public health perspective, the transport mobility situation for children and adolescents with CP. Furthermore, the general aim was to identify obstacles for the target group to use public transport and other means of transportation, at the same level as other members of the society, and to suggest improvements that will remove the identified obstacles. Material and methods: Several different data collection methods were used. Data, concerning travel habits and parents' perceived risks regarding transportation, were taken from a postal questionnaire addressed to parents of children and adolescents with CP. In order to estimate the numbers of potential learner drivers with CP in each age group in Sweden, a literature review was conducted, based on Swedish material. Furthermore, logbooks for learner drivers with CP were analysed retrospectively, in order to identify procedures, problems and key tasks in their driver education. Visual search strategies for learner drivers with CP were analysed, utilizing an eye tracker, and an attempt was made to introduce a screening tool for predicting the outcome of driver education. Results: Children and adolescents with CP were found to be transported under unsafe conditions, causing worry among their parents. When transporting children in the family vehicle, the parents were exposed to a very heavy burden, which increased their worry. The prevalence of potential learner drivers with CP who were in need of highly specialised driver education, including individually adapted driver training vehicles, was estimated to be 0.15 per 1,000 of a population-based age group of learner drivers in Sweden. Complex procedures, structural problems and financial obstacles made it difficult for adolescents with CP to obtain a driving licence and an adapted vehicle. The total duration of the driving tuition given by a driving instructor was found to be almost nine times higher for learner drivers with CP than for non-disabled learner drivers. Visual search strategies among learner drivers with CP were found to be less flexible than among other learner drivers. This fact indicated a need for better methods of teaching such strategies to this group as an integral component of their driver education. The validity of the motor-free visual perceptual test, TVPS-UL, for predicting the outcome of driver education for learner drivers, was found to be low. In order to find a reliable and valid screening tool for this purpose, future studies should focus on cross-validation of visual perceptual and dual task performance tests for different types of independent variables, such as obtaining a driving licence or not, accident involvement and driving ability. Conclusion: The transport system was found, from a legislative and public health perspective, to be unsuitable to meet the needs of children and adolescents with CP. Suggestions for improving transport mobility for children and adolescents with CP are provided. Several of these suggestions are practical, concrete and contextual for Swedish conditions, and some of them necessitate future research. However, a number of these suggestions are also applicable in an international context.     

Graded changes in enamel component volumes resulted from a short tooth bleaching procedure

AimTo test the hypothesis that changes in enamel component volumes (mineral, organic, and water volumes, and permeability) are graded from outer to inner enamel after a short bleaching procedure.Materials and methodsExtracted unerupted human third molars had half of their crowns bleached (single bleaching session, 3 × 15 min), and tooth shade changes in bleached parts were analyzed with a spectrophotometer. Ground sections were prepared, component volumes and permeability were quantified at histological points located at varying distances from the enamel surface (n = 10 points/location), representing conditions before and after bleaching.ResultsTooth shade changes were significant (p < 0.001; 95% CI = −1/−8; power = 99%), and most of the enamel layer was unaffected after bleaching, except at the outer layers. Multiple analysis of covariances revealed that most of the variance of the change in enamel composition after bleaching was explained by the combination of the set of types of component volume (in decreasing order of relevance: mineral loss, organic gain, water gain, and decrease in permeability) with the set of distances from the enamel surface (graded from the enamel surface inward) (canonical R² = 0.97; p < 0.0001; power > 99%).ConclusionsChanges in enamel composition after a short bleaching procedure followed a gradient within component volumes (mineral loss > organic gain > water gain > decrease in permeability) and decreased from the enamel surface inward.     

On the Diagnostic Relevance of Level Discrimination

In his letter to the editor ‘On the use of discrimination of level differences as a diagnostic test procedure as suggested by Fastl and Schorn [1981]’, Dr. Humes questions the diagnostic relevance of level discrimination. His main argument is the overlap of individual data in patients with cochlear versus retrocochlear disorders. We show that the test proposed can differentiate between these types of disorders for test frequencies in the mid-frequency range and suggest that this test be incorporated into the audiological test battery.

Pour répondre à la critique de Larry E. Humes, les auteurs ont precédé à une nouvelle analyse de leurs résultats. N'ayant obtenu que 5-15% de faux-positifs, ils confirment la validité de leur test, étant entendu qu'il convient de l'intégrer à une batterie de tests audiomé-triques.     

江苏省脊髓灰质炎实验室细胞系敏感性实验方法的建立和监测

目的评价江苏省疾病预防控制中心脊髓灰质炎（脊灰）实验室所用细胞系对脊灰病毒的敏感性，制备江苏省脊灰实验室的标准毒株（QC）。方法采用96孔微量培养板滴定法。结果江苏省脊灰实验QC3次独立的细胞敏感性实验结果的滴度波动为±0．5 log 10CCID50，同时用中国疾病预防控制中心病毒病预防控制所国家脊灰实验室提供的已知滴度的Sabin参考株（China Sabin Test Reference Strain；CSTRS）做平行对照，CSTRS株3次滴度结果与其本身提供的参考值相比较，其滴度波动也均为±0．5细10CCID50。结论江苏省脊灰实验室QC结果符合实验要求，脊灰实验室所用细胞系对脊灰病毒的敏感性未下降。是敏感、有效的。