Combining the Hanning windowed interpolated FFT in both directions

The interpolated fast Fourier transform (IFFT) has been proposed as a way to eliminate the picket fence effect (PFE) of the fast Fourier transform. The modulus based IFFT, cited in most relevant references, makes use of only the 1st and 2nd highest spectral lines. An approach using three principal spectral lines is proposed. This new approach combines both directions of the complex spectrum based IFFT with the Hanning window. The optimal weight to minimize the estimation variance is established on the first order Taylor series expansion of noise interference. A numerical simulation is carried out, and the results are compared with the Cramer-Rao bound. It is demonstrated that the proposed approach has a lower estimation variance than the two-spectral-line approach. The improvement depends on the extent of sampling deviating from the coherent condition, and the best is decreasing variance by 2/7. However, it is also shown that the estimation variance of the windowed IFFT with the Hanning is significantly higher than that of without windowing.     

建立肿瘤血管生成抑制剂的体外筛选方法

以Avastin为阳性药,建立稳定、客观的肿瘤血管生成抑制剂的体外评价体系。用CCK-8检测人脐静脉内皮细胞（HUVECs）的增殖情况;荧光定量的Boyden小室法检验HUVECs的迁移能力;荧光定量分析HUVECs对纤维蛋白的粘附能力;运用图象分析软件Image—ProPlus定量分析HUVECs的小管形成行为的图像。结果表明,在该体系中,Avastin能够抑制VEGF诱导的HUVECs与血管生成相关的生物学行为。该体系具有操作简单、可重复性好、易量化的特点,是一种在体外筛选肿瘤血管生成抑制剂的理想模型。     

孤束核微注射内皮素-1(1-31)对心血管活动的影响

目的: 观察内皮素-1(1-31)[ET-1(1-31)] 在大鼠孤束核(Nucleus tracts solitarius, NTS)产生的心血管效应,并探讨其作用机制。方法: 雄性SD大鼠90只,其中50只随机分为双侧NTS注射组、单侧NTS注射组和人工脑脊液(aCSF)组,分别在双侧或单侧NTS微量注射ET-1(1-31) (0.5~2.0 pmoL)或aCSF (100 nL),观察ET-1(1-31) 在NTS内的心血管效应。11只大鼠观察ET-1(1-31) (1.0 pmoL)在NTS水平对动脉压力反射功能(BRS)产生的影响。其余29只大鼠分别预先给予ET_A受体拮抗剂BQ₁₂₃、ET_B受体拮抗剂BQ₇₈₈、非选择性谷氨酸受体拮抗剂犬尿烯酸(KYN)或对照(aCSF),探讨ET-1(1-31)在大鼠NTS内产生的心血管效应机制。结果: 在大鼠NTS双侧或单侧微量注射ET-1(1-31)剂量依赖性降低大鼠血压并减缓心率;NTS双侧微注射ET-1(1-31)(1 pmoL) 显著减弱大鼠BRS(P<0.05);ET_A受体拮抗剂BQ₁₂₃ 或KYN显著减弱单侧NTS微量注射ET-1(1-31)(1.0 pmoL)产生的降低血压和减缓心率作用(P<0.05);单侧NTS注射ET_B受体拮抗剂BQ₇₈₈对NTS微量注射ET-1(1-31)(1.0 pmoL)产生的降低血压和减缓心率作用没有显著的影响(P>0.05)。结论: NTS微量注射ET-1(1-31)能够降低麻醉大鼠的血压并减缓心率,其作用可能是由ET_A受体和谷氨酸受体所介导。     

Rollback reconstruction for TDC enhanced perfusion imaging

Tomographic perfusion imaging is a significant imaging modality for stroke diagnosis.However,the low rotational speed of the C-arm(6-8 s per circle)is a chal-le...     

Ionic Colloidal Molding as a Biomimetic Scaffolding Strategy for Uniform Bone Tissue Regeneration

Inspired by the highly ordered nanostructure of bone, nanodopant composite biomaterials are gaining special attention for their ability to guide bone tissue regeneration through structural and biological cues. However, bone malformation in orthopedic surgery is a lingering issue, partly due to the high surface energy of traditional nanoparticles contributing to aggregation and inhomogeneity. Recently, carboxyl‐functionalized synthetic polymers have been shown to mimic the carboxyl‐rich surface motifs of non‐collagenous proteins in stabilizing hydroxyapatite and directing intrafibrillar mineralization in‐vitro. Based on this biomimetic approach, it is herein demonstrated that carboxyl functionalization of poly(lactic‐co‐glycolic acid) can achieve great material homogeneity in nanocomposites. This ionic colloidal molding method stabilizes hydroxyapatite precursors to confer even nanodopant packing, improving therapeutic outcomes in bone repair by remarkably improving mechanical properties of nanocomposites and optimizing controlled drug release, resulting in better cell in‐growth and osteogenic differentiation. Lastly, better controlled biomaterial degradation significantly improved osteointegration, translating to highly regular bone formation with minimal fibrous tissue and increased bone density in rabbit radial defect models. Ionic colloidal molding is a simple yet effective approach of achieving materials homogeneity and modulating crystal nucleation, serving as an excellent biomimetic scaffolding strategy to rebuild natural bone integrity.     

盆腔出血性疾病卵巢动脉栓塞治疗

目的评价盆腔出血性疾病经导管栓塞卵巢动脉（OVA）的疗效和安全性。方法对１２例OVA参与盆腔出血性疾病供血的患者进行选择性OVA栓塞术，在栓塞OVA之前均曾行常规髂内动脉前支－子宫动脉栓塞术。出血的病因包括产后出血６例，盆腔血管畸形２例，子宫肌瘤、子宫颈癌、子宫肌瘤术后、盆腔纤维肉瘤各１例。１２例中，７例于第１次介入治疗栓塞两侧髂内动脉－子宫动脉后未能控制出血，第２次造影显示OVA参与出血的供血，５例于栓塞两侧髂内动脉－子宫动脉后发现OVA参与病变供血。栓塞OVA的材料用PVA３例、PVA＋明胶海绵颗粒７例、PVA＋明胶海绵颗粒＋微型钢圈２例。结果选择性OVA造影显示对比剂外溢至宫腔（盆腔）１０例、OVA参与病变供血２例，未显示髂内动脉和其他侧支参与供血。选择性栓塞OVA的技术成功率为１００％，包括栓塞两侧OVA者４例、单侧者８例，未发生与栓塞术相关的并发症。１２例患者经补充栓塞参与出血或病变的OVA后出血立即停止，住院期间未再复发出血。术后随访２周～３６个月，３例术后２～３周子宫切除，１例盆腔纤维肉瘤术后接受放射治疗，１例盆腔动静脉畸形出院后仍有间歇少量阴道出血、未特殊处理，２例出现一过性卵巢功能减退症状，分别于术后３、４个月恢复正常月经。其余７例在随访期间未复发出血、月经周期正常。结论OVA可参与盆腔出血性疾病的供血，是导致常规栓塞两侧髂内动脉－子宫动脉不能控制出血的原因之一。如发现OVA参与盆腔出血性病变的供血，补充做OVA栓塞术是安全和有效的。     

DESIGN AND IMPLEMENTATION OF A WEARABLE,MULTIPARAMETER PHYSIOLOGICAL MONITORING SYSTEM FOR THE STUDY OF HUMAN HEAT STRESS,COLD STRESS,AND THERMAL COMFORT

This article describes the design and implementation of a wearable, multiparameter physiological monitoring system called the Sensing Belt system, which consists of multiple sensors integrated into fabric that communicates with a physiological data acquisition unit (PDAU) that in turn transmits these data to a remote monitoring center (RMC) for analysis. A number of vital signs can be acquired by the system, including electrocardiography (ECG), respiratory inductance plethysmograph (RIP), posture/activity, multipoint skin temperature (T_SK), and rectal temperature (T_RC). The physiological data can be stored on a MicroSD card or transmitted to the RMC, where specialized analysis will be provided to extract parameters such as heart rate (HR), respiratory rate (RR), respiratory sinus arrhythmia (RSA), and human energy expenditure. The RMC can receive physiological data from up to 16 Sensing Belt users simultaneously. A medical validation test was carried out to compare the accuracy of the physiological data obtained from the Sensing Belt system with data obtained concurrently from traditional, calibrated laboratory physiological monitoring instruments. The results showed that most of the variables measured by the Sensing Belt are within acceptable error limits. The mean temperature on two trials (walking and running) showed significantly higher mean differences than on other trials, but the correlation coefficient (r) remained high (0.985 and 0.989, respectively). This study demonstrates the accuracy of the Sensing Belt system for the monitoring of these physiological parameters and suggests that it could be used to provide a complete human physiological monitoring platform for the study of human heat stress, cold stress, and thermal comfort.