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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.
Two types of spherical zirconyl oxalate aqueous sols were successfully customized by a reverse micelles-mediated aqueous sol-gel process, and the sols were sequentially spin-coated on porous supports to prepare ZrO2 loose/tight bilayer ultrafiltration membranes. After three times of spin-coating process, a defect-free ZrO2 loose ultrafiltration membrane with pure water permeability of 110.5 ± 2.25 L m?2 h-1 bar-1, molecular weight cut-off (MWCO) of 16.5 kDa and excellent rejection of up to 97.5 % for bovine serum albumin was fabricated. Then, the loose ultrafiltration membrane was used as a substrate to prepare ZrO2 tight ultrafiltration membrane. Performances of tight ultrafiltration membrane regarding to permeability, retention of polyethylene glycol and treatment of dyes wastewater were evaluated. The tight ultrafiltration membrane with a thickness of 200 nm exhibited a pure water permeability of 22.5 ± 0.3 L m-2 h-1 bar-1 and MWCO of 1150 Da. Additionally, the rejections of methyl red and methyl orange by the tight ultrafiltration membrane were both <65 %, while of alizarin red, direct red, bromocresol green and methyl blue achieved maximum values of 98.5 %, 99.2 %, 99.5 % and 99.6 %, respectively. The fouled membranes could restore the virgin performance for reuse by cleaning and low-temperature calcination.  相似文献   
3.
针对呼吸道系统疾病与大气 PM2:5、 SO2 浓度序列的相关性特征, 应用多重分形消除趋势波动分析法 (MF-DCCA), 对张家界市永定区呼吸道系统疾病患病人数与大气 PM2:5、 SO2 浓度序列进行了研究。结果发现该地区 呼吸道系统疾病患病人数与大气 PM2:5、 SO2 浓度的相关性具有长期持续特征和多重分形特征。随后对它们相关性 多重分形特征的动力来源进行了分析, 通过随机重排和相位随机处理, 结果表明在不同时间尺度上的长期持续性影响 是其主要动力来源。进一步研究发现该地区呼吸道系统疾病与大气 PM2:5、 SO2 浓度序列的相关性在四个季节均具 有长期持续性的多重分形特征, 且夏季多重分形特征相对强于其他季节。  相似文献   
4.
The turbulent boundary layer control on NACA 0012 airfoil with Mach number ranging from 0.3 to 0.5 by a spanwise array of dielectric barrier discharge(DBD)plasma actuators by hot-film sensor technology is investigated.Due to temperature change mainly caused through heat produced along with plasma will lead to measurement error of shear stress measured by hot-film sensor,the correction method that takes account of the change measured by another sensor is used and works well.In order to achieve the value of shear stress change,we combine computational fluid dynamics computation with experiment to calibrate the hot-film sensor.To test the stability of the hot-film sensor,seven repeated measurements of shear stress at Ma = 0.3 are conducted and show that confidence interval of hot-film sensor measurement is from-0.18 to 0.18 Pa and the root mean square is 0.11 Pa giving a relative error 0.5%over all Mach numbers in this experiment.The research on the turbulent boundary layer control with DBD plasma actuators demonstrates that the control makes shear stress increase by about 6%over the three Mach numbers,which is thought to be reliable through comparing it with the relative error 0.5%,and the value is hardly affected by burst frequency and excitation voltage.  相似文献   
5.
为了直观描述金属圆波导中电磁场复杂的空间分布,本文用Comsol软件对金属圆波导中的TE11模、TE01模、和TM01模的电磁场结构进行动态仿真.将电磁场中的抽象概念形象化、可视化,使学生看清电磁场分布的宏观概况和细节变化,开拓了视野,同时加深了学生对电磁波传播特性的理解.  相似文献   
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7.
YUE WANG  YUNFEI ZHENG  WEIRAN LI 《Biocell》2021,45(2):427-444
Orthodontic tooth movement is triggered by orthodontic force loading on the periodontal ligament and is achieved by alveolar bone remodeling, which is regulated by intimate crosstalk between osteoclastogenesis and osteoblast differentiation. Whether the communication between osteoclasts and osteoblasts is influenced by orthodontic compression stress requires further clarification. In this study, osteoclasts were differentiated for 10 days. On day 4 of differentiation, the number of pre-osteoclasts peaked, as determined by the increased expression of RANK and the number of multinucleated cells. After 24 h of compression stress loading, on day 4, the number of osteoclasts increased, and the optimal magnitude of stress to promote osteoclastogenesis was determined as 1 g/cm2. Moreover, the results of RNA-sequencing analysis showed that the miRNA expression profile changed markedly after compression loading and that many of the altered miRNAs were associated with cell communication functions. A series of indirect co-culture experiments showed an inhibitory effect of osteoclasts on osteoblast differentiation, especially after compression. Next, we added osteoclast-derived exosomes to hPDLSCs during osteoblast differentiation. Exosomes derived from osteoclasts under compression (cEXO) showed a greater inhibitory effect on osteoblast differentiation, compared to exosomes from osteoclasts without compression (EXO). Therefore, we analyzed differentially expressed miRNAs associated with bone development functions in exosomes: miR-223-5p and miR-181a-5p were downregulated, whereas miR-133a-3p, miR-203a-3p, miR-106a-5p, and miR-331-3p were upregulated; these altered expressions may explain the enhanced inhibitory effect of compression stress.  相似文献   
8.
基于GA-BP的汽车风振噪声声品质预测模型   总被引:1,自引:1,他引:0  
目前对于汽车风振噪声的优化研究主要以声压级(Sound pressure level,SPL)作为单一评价指标,既不能全面反映噪声的物理属性,也无法考虑人耳对噪声的主观认知过程。为准确评价风振噪声,引入声品质,运用大涡模拟(Large eddy simulation,LES)对风振噪声进行数值仿真,根据实车道路试验判断仿真的准确性;对仿真结果进行声品质客观评价与主观评价,综合声品质客观评价参数与声品质主观评价试验结果建立BP神经网络预测模型;利用遗传算法(Genetic algorithm,GA),进一步对BP神经网络的结构参数进行优化,建立GA-BP声品质预测模型。研究结果表明,GA-BP声品质预测模型在训练速度和预测精度上都优于BP神经网络预测模型。预测模型基于声品质主客观评价结果,其预测值可以代替传统的声压级评价指标,为风振噪声提供更为准确合理的评价。  相似文献   
9.
10.
杨立宁  郑东昊  王立新  杨光 《化工进展》2022,41(11):5961-5967
以具有轻质高强优异性能的蜻蜓翅脉结构为设计灵感,在分析翅脉网格结构抗冲击原理的基础上,设计了传统和仿生两类对比结构。采用熔融挤出3D打印机成功制备了具有不同结构的连续碳纤维增强聚乳酸复合材料试样,并对不同结构复合材料试样的拉伸性能和抗冲击性能进行了测试和对比分析。研究分析结果表明:由于拉伸力方向上的连续碳纤维含量相对较少,限制了仿生结构复合材料抗拉强度的提高,但仿生结构的平均抗拉强度为传统结构的1.18倍;当仿生结构复合材料试样受到冲击力时,其内部六边形结构的连接角度会发生变化,从而极大消耗冲击能量,同时具有六边形网格结构的连续碳纤维可以有效阻碍裂纹的扩展,因此仿生结构的平均冲击韧性可以达到传统结构的2.46倍;仿生蜻蜓翅脉结构可以显著提高增材制造复合材料的综合力学性能,且对于抗冲击性能的提高具体突出效果。连续碳纤维增强树脂基复合材料的有效可行的仿生蜻蜓翅脉结构设计和增材制造,可极大扩展其在高冲击载荷领域中的相应应用。  相似文献   
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