Speech Separation Methodology for Hearing Aid

In the design of hearing aids (HA), the real-time speech-enhancement is done. The digital hearing aids should provide high signal-to-noise ratio, gain improvement and should eliminate feedback. In generic hearing aids the performance towards different frequencies varies and non uniform. Existing noise cancellation and speech separation methods drops the voice magnitude under the noise environment. The performance of the HA for frequency response is non uniform. Existing noise suppression methods reduce the required signal strength also. So, the performance of uniform sub band analysis is poor when hearing aid is concern. In this paper, a speech separation method using Non-negative Matrix Factorization (NMF) algorithm is proposed for wavelet decomposition. The Proposed non-uniform filter-bank was validated by parameters like band power, Signal-to-noise ratio (SNR), Mean Square Error (MSE), Signal to Noise and Distortion Ratio (SINAD), Spurious-free dynamic range (SFDR), error and time. The speech recordings before and after separation was evaluated for quality using objective speech quality measures International Telecommunication Union -Telecommunication standard ITU-T P.862.     

改造FK501型绢纺细纱机、纺制苎麻纱的生产实践

针对FK501型绢纺细纱机的设备工艺特性，参照FZ501、DJ562C(Z)麻纺细纱机，对FK501型绢纺细纱机原机牵伸装置，牵伸传动、捻度、卷绕成形系统进行了适当的改造，使之成功地用于苎麻纺纱生产。     

双动技术在高压SF6断路器中的应用

介绍了双动技术的原理,分析了采用双动技术的AREVA公司GL312型SF6断路器及其配套的FK3-X系列弹簧操作机构的技术优点。     

线性时差校正技术在噪音压制中的应用

对于一个横向、纵向偏移距比较大的三维地震数据而言,折射波等噪音的线性形态会随着横向偏移距的加大而向着双曲线形态变化。当炮点位于某检波点线附近,横向偏移距较小的情况下,该检波线接收到的线性噪音在地震记录上呈线性状态分布;当炮点远离排列,横向偏移距比较大时,该排列单炮上的线性噪音则呈双曲线形态,并且随着横向偏移距的加大双曲现象就越明显。常规FK滤波等压制线性噪音的方法,对于这种由于横向偏移距增大而引起的非线性噪音其压制能力较差。笔者采用线性时差校正的方法,首先将横向偏移距对线性噪音旅行时的影响消除掉,恢复其线性形态,再应用线性噪音压制技术将其压制掉,最后进行反线性时差校正,以达到高精度噪音压制的目的。目前这种方法在宽方位角采集的数据上取得比较好的效果。      

Synthesis and biological evaluation of isosteric analogues of FK866, an inhibitor of NAD salvage

One of the great challenges of medicinal chemistry is to create novel, effective, chemotherapeutic agents that show specificity for cancer cells combined with low systemic toxicity. A novel idea is to target the enzymes of the NAD biosynthesis and recycling pathways given that cancer cells display a higher NAD turnover rate than healthy cells. To this end, the compound FK866 (APO866; (E)-N-[4-(1-benzoylpiperidin-4-yl) butyl]-3-(pyridin-3-yl) acrylamide), which blocks nicotinamide phosphoribosyltransferase (NMPRTase) has entered clinical trials as a potential chemotherapeutic agent. Here we report the synthesis of analogues of FK866 synthesized by click chemistry.     

Fenton-Chemistry-Based Oxidative Modification of Proteins Reflects Their Conformation

In order to understand protein structure to a sufficient extent for, e.g., drug discovery, no single technique can provide satisfactory information on both the lowest-energy conformation and on dynamic changes over time (the ‘four-dimensional’ protein structure). Instead, a combination of complementary techniques is required. Mass spectrometry methods have shown promise in addressing protein dynamics, but often rely on the use of high-end commercial or custom instruments. Here, we apply well-established chemistry to conformation-sensitive oxidative protein labelling on a timescale of a few seconds, followed by analysis through a routine protein analysis workflow. For a set of model proteins, we show that site selectivity of labelling can indeed be rationalised in terms of known structural information, and that conformational changes induced by ligand binding are reflected in the modification pattern. In addition to conventional bottom-up analysis, further insights are obtained from intact mass measurement and native mass spectrometry. We believe that this method will provide a valuable and robust addition to the ‘toolbox’ of mass spectrometry researchers studying higher-order protein structure.     

FK506-binding protein mutational analysis: defining the active-site residue contributions to catalysis and the stability of ligand complexes

The 12 kDa FK506-binding protein FKBP12 is a cis-trans peptidyl-prolylisomerase that binds the macrolides FK506 and rapamycin. Wehave examined the role of the binding pocket residues of FKBP12in protein–ligand interactions by making conservativesubstitutions of 12 of these residues by site-directed mutagenesis.For each mutant FKBP12, we measured the affinity for FK506 andrapamycin and the catalytic efficiency in the cis–transpeptidyl-prolyl isomerase reaction. The mutation of Trp59 orPhe99 generates an FKBP12 with a significantly lower affinityfor FK506 than wild-type protein. Tyr26 and Tyr82 mutants areenzymatically active, demonstrating that hydrogen bonding bythese residues is not required for catalysis of the cis–transpeptidyl-prolyl isomerase reaction, although these mutationsalter the substrate specificity of the enzyme. We conclude thathydrophobic interactions in the active site dominate in thestabilization of FKBP12 binding to macrolide ligands and tothe twisted-amide peptidyl-prolyl substrate intermediate.     

瑞利波SASW法与F-K法模拟测试比较

获取与瑞利波理论频散曲线相匹配的实测频散曲线是正确反演土层参数及分布的前提,表面波谱分析（SASW）法和频率．波数（F-K）法是求取瑞利波实测频散曲线的两种主要方法。采用传递矩阵法计算得到瑞利波在各种典型地层模型地表处时域内的振动信息,作为SASW法和F-K法的测试数据进行了模拟测试。分别将两种方法得到的实测频散曲线与理论频散曲线对比。分析了道距、偏移距和道数等测试参数的影响,以及两种方法对于各种典型地层的测试效果。结果表明,测试参数对两种方法的影响有所不同,选择合适的测试参数能够得到好的测试效果,道数相同时F-K法的测试效果优于SASW法,多通道F-K法的测试效果优于少通道F—K法。     

PDLLA/HA/FK506复合神经导管的制备及体外降解性能

以聚乳酸（PDLLA）为基材、纳米羟基磷灰石（HA）为添加剂、加入免疫抑制剂FK506，用溶剂挥发法制备PDLLA／HA/FK506复合神经导管。通过观察复合导管在磷酸缓冲溶液中降解时pH值变化、质量损耗及材料微观形貌，研究了该复合导管的体外降解性能。结果表明：加入适量纳米羟基磷灰石可以改善聚乳酸降解的酸性问题并提高其力学强度。免疫抑制剂FK506的加入对导管材料的降解性能有一定的影响。PDLLA/HA／FK506复合神经导管具有良好的降解性能。     

Is PTSD-Phenotype Associated with HPA-Axis Sensitivity? Feedback Inhibition and Other Modulating Factors of Glucocorticoid Signaling Dynamics

Previously, we found that basal corticosterone pulsatility significantly impacts the vulnerability for developing post-traumatic stress disorder (PTSD). Rats that exhibited PTSD-phenotype were characterized by blunted basal corticosterone pulsatility amplitude and a blunted corticosterone response to a stressor. This study sought to identify the mechanisms underlining both the loss of pulsatility and differences in downstream responses. Serial blood samples were collected manually via jugular vein cannula at 10-min intervals to evaluate suppression of corticosterone following methylprednisolone administration. The rats were exposed to predator scent stress (PSS) after 24 h, and behavioral responses were assessed 7 days post-exposure for retrospective classification into behavioral response groups. Brains were harvested for measurements of the glucocorticoid receptor, mineralocorticoid receptor, FK506-binding protein-51 and arginine vasopressin in specific brain regions to assess changes in hypothalamus–pituitary–adrenal axis (HPA) regulating factors. Methylprednisolone produced greater suppression of corticosterone in the PTSD-phenotype group. During the suppression, the PTSD-phenotype rats showed a significantly more pronounced pulsatile activity. In addition, the PTSD-phenotype group showed distinct changes in the ventral and dorsal CA1, dentate gyrus as well as in the paraventricular nucleus and supra-optic nucleus. These results demonstrate a pre-trauma vulnerability state that is characterized by an over-reactivity of the HPA and changes in its regulating factors.