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121.
Offers the author's recall of a personal exchange with Freud when Rosenzweig was a young psychologist, a memory prompted by the article by L. T. Benjamin, Jr. and D. N. Dixon (see record 83-32709) which discussed Freud's characteristics as a correspondent in general. In letters on 2 separate occasions, the author remembers that Freud made a similar negative response to any attempts to explore psychoanalytic theory by laboratory methods. This exchange clearly underscored Freud's distrust of, if not opposition to, experimental approaches to the validation of his clinically derived concepts. These letters are reproduced elsewhere with commentary (S. Rosenzweig, 1985). (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
122.
Impedance characteristics of quantum-well lasers   总被引:1,自引:0,他引:1  
We derive theoretical expressions for the impedance of quantum-well lasers below and above threshold based on a simple rate equation model. These electrical laser characteristics are shown to be dominated by purely electrical parameters related to carrier capture/transport and carrier re-emission. The results of on-wafer measurements of the impedance of high-speed In0.35Ga0.65 As/GaAs multiple-quantum-well lasers are shown to be in good agreement with this simple model, allowing us to extract the effective carrier escape time and the effective carrier lifetime, and to estimate the effective carrier capture/transport time  相似文献   
123.
On-wafer measurements of the frequency-dependent impedance, modulation response, and RIN power spectra of ultra-high-speed p-doped In0.35Ga0.65As/GaAs MQW lasers are presented and analyzed. The experimental results are shown to be accurately modeled by an equivalent circuit which accounts for both the carrier transport/capture dynamics and the junction space-charge capacitance. We find that the carrier escape time out of the QW's in our laser structure is much larger. Than the carrier capture time, and therefore the interplay between carrier capture and re-emission is not affecting the high-speed modulation dynamics. On the other hand, the absolute values of both the carrier capture time and the space-charge capacitance still limit the modulation bandwidth  相似文献   
124.
The American Psychological Association Council in February 1987 passed a resolution declaring that "the discipline of psychology, and the academic and professional activities of psychologists, are relevant for securing and maintaining human rights" and resolving that "the APA applauds the ongoing efforts of the United Nations to defend and protect human rights and undertakes to recommend the main UN human rights instruments and documents to the attention of its boards, committees, and membership at large." To help to implement this resolution, the present article first provides information about the development of human rights concepts and instruments; treaties and declarations concerning torture are used as examples, and the impact of these international agreements is shown in a recent history-making U.S. legal decision. Second, the article reviews APA human rights policies and actions and offers some conclusions about them. Third, it calls attention to a number of specific international statements of human rights that are relevant to psychology. Fourth, the article suggests some further steps that APA could take to implement its resolution. Finally, it provides references to sources that include the texts of the United Nations' human rights instruments and information about them. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
125.
Traditional intensity modulated two-level electrical time-division multiplexing(ETDM)transmission systems working at 100-112Gbit/s were investigated.The complete ETDM systems based on monolithically integrated transmitter and receiver modules were demonstrated with bit-error-rate(BER)performance of 10-8 at 107Gbit/s,and near error-free standard forward error correction(FEC)threshold(2×10-3)at 112Gbit/s.The experiment results showed that directly modulated high-speed ETDM transmission systems with the symbol rates at 100Gbaud and beyond were promising candidate for cost-effective 100GbE applications and might be a preform of the next generation of Terabit/s Ethernet.  相似文献   
126.
This paper is a summary of the discussions undertaken by the working group on injection and accelerated beam dynamics at the 1st ICFA Novel and Advanced Accelerator Workshop on Second Generation Plasma Accelerators. The second generation of work on plasma accelerators is aimed to bring the accelerated beams up to the quality needed for applications such as high-energy physics linear colliders. To begin, first generation, or proof-of-principle, experiments and concepts were reviewed. To map the work needed in the second generation of development, the demands of the applications were examined, and an improved framework for discussing the viability of plasma accelerators was constructed. In particular, the issues scaling applications to the short wavelengths characteristic of plasma accelerators was discussed, as was the appropriate characterization of the beam quality in these devices, and the connection between plasma accelerator and conventional accelerator design. Within this framework, the working group discussed electron sources and injectors, the effects of drive beam evolution on accelerated beam dynamics, this effects of nonlinear plasma wave fields on beam phase space, stochastic processes, spatial and temporal beam-plasma wave matching, and future second-generation experimental goals and techniques.  相似文献   
127.
The RF photoinjector in the Neptune advanced accelerator laboratory, along with associated beam diagnostics, transport and phase-space manipulation techniques are described. This versatile injector has been designed to produce short-pulse electron beams for a variety of uses: ultra-short bunches for injection into a next-generation plasma beatwave acceleration experiment, space-charge dominated beam physics studies, plasma wake-field acceleration driver, plasma lensing, and free-electron laser microbunching techniques. The component parts of the photoinjector, the RF gun, photocathode drive laser systems, booster linac, RF system, chicane compressor, beam diagnostic systems, and control system, are discussed. The present status of photoinjector commissioning at Neptune is reviewed, and proposed experiments are detailed.  相似文献   
128.
A quantitative “Round Neck” (RN) model based upon volume balances and considerations of surface tension phenomena is proposed for simulation of coalescence of two spherical polymeric particles; during sintering. This model and an early model developed by Frenkel are compared and evaluated against experimental data to show their suitability to simulate geometrical variations of a particle pair during sintering.  相似文献   
129.
Dysregulated redox balance is involved in the pathogenesis of type 2 diabetes. While the benefit of antioxidants in neutralizing oxidative stress is well characterized, the potential harm of antioxidant-induced reductive stress is unclear. The aim of this study was to investigate the dose-dependent effects of the antioxidant N-acetylcysteine (NAC) on various tissues involved in the regulation of blood glucose and the mechanisms underlying its functions. H2O2 was used as an oxidizing agent in order to compare the outcomes of oxidative and reductive stress on cellular function. Cellular death in pancreatic islets and diminished insulin secretion were facilitated by H2O2-induced oxidative stress but not by NAC. On the other hand, myotubes and adipocytes were negatively affected by NAC-induced reductive stress, as demonstrated by the impaired transmission of insulin signaling and glucose transport, as opposed to H2O2-stimulatory action. This was accompanied by redox balance alteration and thiol modifications of proteins. The NAC-induced deterioration of insulin signaling was also observed in healthy mice, while both insulin secretion and insulin signaling were improved in diabetic mice. This study establishes the tissue-specific effects of NAC and the importance of the delicate maintenance of redox balance, emphasizing the challenge of implementing antioxidant therapy in the clinic.  相似文献   
130.
Bone is a frequent site of tumor metastasis. The bone–tumor microenvironment is heterogeneous and complex in nature. Such complexity is compounded by relations between metastatic and bone cells influencing their sensitivity/resistance to chemotherapeutics. Standard chemotherapeutics may not show efficacy for every patient, and new therapeutics are slow to emerge, owing to the limitations of existing 2D/3D models. We previously developed a 3D interface model for personalized therapeutic screening, consisting of an electrospun poly lactic acid mesh activated with plasma species and seeded with stromal cells. Tumor cells embedded in an alginate-gelatin hydrogel are overlaid to create a physiologic 3D interface. Here, we applied our 3D model as a migration assay tool to verify the migratory behavior of different patient-derived bone metastasized cells. We assessed the impact of two different chemotherapeutics, Doxorubicin and Cisplatin, on migration of patient cells and their immortalized cell line counterparts. We observed different migratory behaviors and cellular metabolic activities blocked with both Doxorubicin and Cisplatin treatment; however, higher efficiency or lower IC50 was observed with Doxorubicin. Gene expression analysis of MDA-MB231 that migrated through our 3D hybrid model verified epithelial–mesenchymal transition through increased expression of mesenchymal markers involved in the metastasis process. Our findings indicate that we can model tumor migration in vivo, in line with different cell characteristics and it may be a suitable drug screening tool for personalized medicine approaches in metastatic cancer treatment.  相似文献   
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