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1.
The germline carrier of the BRCA1 pathogenic mutation has been well proven to confer an increased risk of breast and ovarian cancer. Despite BRCA1 biallelic pathogenic mutations being extremely rare, they have been reported to be embryonically lethal or to cause Fanconi anemia (FA). Here we describe a patient who was a 48-year-old female identified with biallelic pathogenic mutations of the BRCA1 gene, with no or very subtle FA-features. She was diagnosed with ovarian cancer and breast cancer at the ages of 43 and 44 and had a strong family history of breast and gynecological cancers.  相似文献   
2.
论述了有色人种护发品市场的现状及未来发展趋势。指出,虽然与有色人种相关的产品大多仅限于美国市场,而且这一市场增长缓慢,但这一市场仍有发展潜力。随着社会就业岗位的增加,有色人种消费者在购买护发产品时变得越来越挑剔,越来越多的非洲女性开始喜炊她们天生的自然卷发,并在市场七寻找可以满足这种需求的创新性优质产品。因此,有色人种护发产品市场将呈现出多样化的趋势。  相似文献   
3.

This paper introduces a Transimpedance Amplifier (TIA) design capable of producing an incremental input resistance in the ohmic range, for input signals in the microampere range, such as are encountered in the design of instrumentation for electrochemical ampero-metric sensors, optical-sensing and current-mode circuits. This low input-resistance is achieved using an input stage incorporating negative feedback. In a Cadence simulation of an exemplary design using a 180 nm CMOS process and operating with?±?1.8 V supply rails, the input resistance is 1.05 ohms and the power dissipation is 93.6 µW. The bandwidth, for a gain of 100 dBohm, exceeded 9 MHz. For a 1µA, 1 MHz sinusoidal input signal the Total Harmonic Distortion, with this gain, is less than 1%. The input referred noise current with zero photodiode capacitance is 2.09 pA/√Hz and with a photodiode capacitance of 2pF is 8.52 pA/√Hz. Graphical data is presented to show the effect of a photodiode capacitance varying from 0.5 to 2 pF, when the TIA is used in optical sensing. In summary, the required very low input resistance, at a low input current level (µA) is achieved and furthermore a Table is included comparing the characteristics and a widely used Figure of Merit (FOM) for the proposed TIA and similar published low-power TIAs. It is apparent from the Table that the FOM of the proposed TIA is better than the FOMs of the other TIAs mentioned.

  相似文献   
4.
We give drawings of a complete graphK n withO(n 4 log2 g/g) many crossings on an orientable or nonorientable surface of genusg 2. We use these drawings ofK n and give a polynomial-time algorithm for drawing any graph withn vertices andm edges withO(m 2 log2 g/g) many crossings on an orientable or nonorientable surface of genusg 2. Moreover, we derive lower bounds on the crossing number of any graph on a surface of genusg 0. The number of crossings in the drawings produced by our algorithm are within a multiplicative factor ofO(log2 g) from the lower bound (and hence from the optimal) for any graph withm 8n andn 2/m g m/64.The research of the third and the fourth authors was partially supported by Grant No. 2/1138/94 of the Slovak Academy of Sciences and by EC Cooperative action IC1000 Algorithms for Future Technologies (Project ALTEC). A preliminary version of this paper was presented at WG93 and published in Lecture Notes in Computer Science, Vol. 790, 1993, pp. 388–396.  相似文献   
5.
As a result of the emerging use of mesh-based multicomputers (and recently mesh-based multiprocessor systems-on-chip), issues related to processor management have attracted much attention. In a mesh-based multiprocessor, after repeated submesh allocations and de-allocations, the system network may be fragmented, i.e. there might be unallocated nodes in the network. As a result, in a system with contiguous processor allocation, no new tasks can start running due to the lack of enough free adjacent processors to form a suitable submesh. Although there might be enough free processors available, they remain idle until the allocator can find a set of adjacent free nodes forming a submesh to be used for the new task. This can lead to low system performance. Task migration was introduced as a solution to this problem through migration of tasks running on some submeshes to other free areas in order to reduce fragmentation by chaining the newly freed areas and disengaging nodes to form larger submeshes. In this paper, we propose a novel structured and formulated way to code task migration, which is helpful for congestion detection in different steps of task migration algorithms. Moreover, considering the fact that the 3D mesh-based multicomputers are now very popular, a new task migration algorithm in 3D meshes is proposed. We also address the special case of the 2D migration in a 3D mesh multicomputer.  相似文献   
6.
7.
In this paper, an adaptive control scheme, based on fuzzy logic systems, for pH control is addressed. For implementation of the proposed scheme no composition measurement is required. Stability of the closed-loop system is established and it is shown that the solution of the closed-loop system is uniformly ultimately bounded and under a certain condition, asymptotical stability is achieved. Effectiveness of the proposed controller is tested through simulation and experimental studies. Results indicate that the proposed controller has good performances in set-point tracking and load rejection and much better than that of a tuned PI controller.  相似文献   
8.
This paper proposes a new method to address a three-dimensional concurrent engineering (3D-CE) approach. It uses a Multi-Objective Linear Programming (MOLP) model integrated to the TOPSIS method in order to determine the best configuration product design, assembly process and suppliers of components. This method is able to involve various supply chain strategies by considering qualitative and quantitative criteria in the early stages of the new product development (NPD) process. It also applies the Fuzzy Analytic Hierarchy Process (FAHP) method to determine the relative importance of criteria defined to evaluate configurations of design alternatives, assembly processes and suppliers of components. A sensitivity analysis from different parameters in the model that affect the selection of the best design alternative is performed by creating a computer program using visual studio. A numerical example is used to demonstrate method efficacy and finally, the paper suggests some areas for future research.  相似文献   
9.
Aytug Ava  Canan  Ocak  Yusuf Selim  Celik  Omer  Asubay  Sezai 《SILICON》2023,15(1):451-458
Silicon - The influence of the Si substitution ratio on the structural, morphological, and optical properties of Cu2ZnSnS4 (CZTS) thin films was examined. The Cu2Zn(SixSn1–x)S4 thin films...  相似文献   
10.
A feedback control scheme for SISO systems with time delays and constrained inputs is proposed. The controller is designed through the internal model control (IMC) technique and the Smith predictor structure is used for dead time compensation. Through computer simulation, the performance of the proposed scheme has been compared with the classic feedback scheme designed via the IMC procedure. The results show that the proposed scheme performs better due to the preservation of the predictive property.  相似文献   
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