安森美半导体针对家庭娱乐应用的音视频、电源管理和电路保护方案

详细介绍了安森美半导体音频、视频、开关控制器、电压监控器、抑制EMI、微控制器、接口滤波及保护等解决方案。     

汽车自动启停系统对电源的影响及非同步升压转换器方案

本文介绍了安森美半导体用于汽车自动启停系统的最新前置升压电源方案NCV8876的功能特点及工作原理。     

Identification of the components of simple protein mixtures by high-accuracy peptide mass mapping and database searching

Peptide mass mapping by matrix-assisted laser desorption/ionization (MALDI) followed by database searching with the set of measured peptide masses is now a powerful method for the identification of pure proteins. Protein mixtures--such as frequently occur due to comigration in polyacrylamide gel bands--have hitherto required protein sequencing. Here we demonstrate that such protein bands can also be analyzed by peptide mass mapping alone. Database searching with the complete list of peptide masses determined by delayed-extraction MALDI mass spectrometry with a mass error of less than 30 ppm retrieves the most prominent protein in a mixture. In a second step, the protein identity is further confirmed by matching as many of the measured peptide masses as possible to the retrieved amino acid sequence. Peptide masses remaining after this "second pass search" are searched again to identify the next component in the protein mixture. This iterative process is repeated until all major ion signals are accounted for. Protein mixtures consisting of two or more individual components in a single gel band can be analyzed, further increasing the general applicability of MALDI peptide mapping for protein identification.     

Molecular basis of lipoamide dehydrogenase deficiency in Ashkenazi Jews

PURPOSE: To measure binocular function and patient satisfaction with monovision induced by photorefractive keratectomy (PRK) in myopic presbyopic patients. SETTING: Refractive Department, Cleveland Clinic, Cleveland, Ohio, USA. METHODS: This study comprised 21 myopic presbyopic patients with monovision induced by PRK. Sixteen emmetropic patients who had PRK served as a control group. Monovision was induced by undercorrecting the nondominant eye by 1.25 diopters for near vision and correcting the dominant eye with emmetropia for distance vision. Monocular and binocular uncorrected Snellen visual acuities at 20 feet and 13 inches, manifest refraction, ocular dominance, stereopsis at 20 feet and 13 inches, monocular and binocular contrast sensitivities, Worth-4-Dot test at 20 feet and 1/3 of a meter, and fusional convergence amplitudes were examined in each patient. RESULTS: In the monovision group at near and distance, 20 patients (95.3%) had binocular visual acuity of 20/25 or better. No patient in the monovision group used reading glasses postoperatively; 4 of 16 patients (25.0%) in the control group used such glasses. All patients maintained binocular fusion and stereo acuity ranging from 40 to 800 seconds of arc. Mean patient satisfaction was 86% (range 40% to 100%). In the control group, 12 patients (75.0%) had binocular distance visual acuity of 20/25 or better and 11 (68.8%) had binocular near visual acuity of 20/25 or better. CONCLUSION: Monovision PRK patients had better near vision than control PRK patients, with minimal compromise in stereo acuity and overall high patient satisfaction.     

针对电信和网络应用的安森美半导体DC-DC电源参考设计示例

文章介绍了电信和网络应用的安森美半导体分布式电源解决方案的设计示例,包括隔离电源转换和非隔离电源转换的解决方案设计示例。     

Thermal Denaturation in Fish Muscle Proteins During Gelling: Effect of Spawning Condition

We studied thermal denaturation of myofibrillar proteins from pre-and post-spawning hake by differential scanning calorimetry (DSC), and evaluated denaturation kinetics under both conditions. The denaturation enthalpies of all pre-spawning fish muscle extracts were less than those from post-spawning. The area under the DSC thermogram corresponding to myosin denaturation was smaller in myofibrillar extracts from pre-spawning than from post-spawning hake, while the areas corresponding to denaturation of actin were similar. Between 40 and 55°C the myosin denaturation rates were greater for post-spawning than for pre-spawning hake. Both entalphies and kinetic data indicated proteins of fish in a better biological condition (post-spawned) denature more rapidly and completely.     

符合“能源之星”固态照明要求的离线高功率因数TRIAC调光LED驱动器参考设计

本文介绍了对固态照明的规范要求,给出了满足这些要求的离线式高功率因数TRIAC调光LED驱动器参考设计方案,以及该方案的测试结果。     

SH1 domain autophosphorylation of P210 BCR/ABL is required for transformation but not growth factor independence

P210 BCR/ABL is a chimeric oncogene implicated in the pathogenesis of chronic myelogenous leukemia. BCR sequences have been shown to be required for activation of the tyrosine kinase and transforming functions of BCR/ABL. In this work, we show that two other structural requirements for full transforming activity of P210 BCR/ABL include a functional tyrosine kinase and the presence of tyrosine 1294, a site of autophosphorylation within the tyrosine kinase domain. Replacement of tyrosine 1294 with phenylalanine (1294F) greatly diminishes the transforming activity of BCR/ABL without affecting the specific activity of the protein tyrosine kinase. Expression of an exogenous myc gene in fibroblasts partially complements the transforming capacity of mutant P210 BCR/ABL (1294F). Surprisingly, tyrosine 1294 is not required for efficient induction of growth factor-independence in hematopoietic cell lines by P210 BCR/ABL. These results suggest that autophosphorylation at tyrosine 1294 may be important for recognition and phosphorylation of cellular substrates in the pathway of transformation, but it is not critical for mediating the events which lead to growth factor independence.     

Diagnosis-related groups: a comparative analysis of hospital activity in different countries

Comparative study of hospital activities in the Novgorod district and nine countries of the European Community, carried out within the framework of the International Project CAMISE (Case Mix and Severity) of the European Community on the basis of the classification system for diagnosis-related groups, showed a lower Case Mix Index, a longer hospital stay for all major disease, and a lower surgical activity in the hospitals of the Novgorod district in comparison with other European countries. The detected differences are largely due to specific features in the organization of hospital service in Russia (no special hospitals for acute and chronic patients, no nursing homes) and insufficiently intensive therapeutic and diagnostic process.