Newton’s method’s basins of attraction revisited

In this paper, we revisit the chaotic number of iterations needed by Newton’s method to converge to a root. Here, we consider a simple modified Newton method depending on a parameter. It is demonstrated using polynomiography that even in the simple algorithm the presence and the position of the convergent regions, i.e. regions where the method converges nicely to a root, can be complicatedly a function of the parameter.     

基于超声RF信号的甲状腺结节智能诊断方法*

由于人口老龄化的原因,甲状腺癌的发病率增长率在所有癌症中是最为显著的。因此,对存在癌变可能的甲状腺结节进行预检查显得尤为重要,而超声智能诊断系统在甲状腺结节早期筛查方面已展现出巨大的应用前景。该文的工作旨在提出一种基于超声原始射频信号的组织参数定征和人工神经网络相结合的甲状腺结节智能诊断方法,以提高临床超声诊察效率及准确性。为达成上述目的,该文使用滑动窗口图像分析方法和多兴趣区覆盖的方法提取组织定征参数作为特征,使用人工神经网络进行良恶性分类,并对可能影响分类准确性的相关因素进行参数相关性分析。结果显示,基于临床样本,该文提出的智能诊断方法可达到93.2%敏感度、94.0%特异性和93.5%准确率。该方法一定程度上克服了传统方法无法充分利用图像局部细节信息的不足,有效提高了诊察效率和准确性;另一方面,与深度神经网络相比,本方法对计算资源和样本量的需求较少。因此有望在该文研究基础上最终建立一套可实际用于甲状腺结节的预筛查的临床智能诊断系统。     

Coping strategies, personality, and voice quality in patients with vocal fold nodules and polyps

Emotional state affects the physiological mechanism involved inphonation. Differences in acoustical parameters of the voice under stress have been attributed to the coping mechanism used, which is based on the individual's perception of the situation. This study examines the relationship between coping strategies, personality, and voice in female subjects, ranging in age from 19.3–55.7 years, diagnosed with vocal nodules or polyps. The differences between coping strategies and personality are examined and compared with another group with no history of voice pathology. The relationship of personality and coping strategies to voice quality variables is reported. Results show that patients use emotional coping strategies more and cognitive coping strategies less than the comparison group. Type of voice pathology was found to be related to dominance, and a number of coping and personality variables were found to correlate significantly with voice quality.     

Accumulation and localization of extensin protein in apoplast of pea root nodule under aluminum stress

Cell wall components such as hydroxyproline-rich glycoproteins (HRGPs, extensins) have been proposed to be involved in aluminum (Al) resistance mechanisms in plants. We have characterized the distribution of extensin in pea (Pisum sativum L.) root nodules apoplast under short (for 2 and 24 h) Al stress. Monoclonal antibodie LM1 have been used to locate extensin protein epitope by immunofluorescence and immunogold labeling.The nodules were shown to respond to Al stress by thickening of plant and infection thread (IT) walls and disturbances in threads growth and bacteria endocytosis. Immunoblot results indicated the presence of a 17-kDa band specific for LM1. Irrespective of the time of Al stress, extensin content increased in root nodules. Further observation utilizing fluorescence and transmission electron microscope showed that LM1 epitope was localized in walls and intercellular spaces of nodule cortex tissues and in the infection threads matrix. Al stress in nodules appears to be associated with higher extensin accumulation in matrix of enlarged thick-walled ITs. In addition to ITs, thickened walls and intercellular spaces of nodule cortex were also associated with intense extensin accumulation.These data suggest that Al-induced extensin accumulation in plant cell walls and ITs matrix may have influence on the process of IT growth and tissue and cell colonization by Rhizobium bacteria.     

Comparison of young adult singers and nonsingers with vocal nodules

Comparisons were made between 10 singers and 10 nonsingers with vocal nodules and two control groups of normals, 10 singers and 10 nonsingers, on a wide range of acoustic, aerodynamic, psychoacoustic, and videostroboscopic measures. Results showed significant differences between the normals and those with nodules as well as differences between the singers and nonsingers. The singers with nodules had smaller nodules, less impairment of vibratory function, and less severe vocal symptoms than their nonsinging counterparts. The singing normals were found to be superior to the nonsinging normals on acoustic measures including jitter, shimmer, and signal-to-noise ratio. In addition, the singers, even in the presence of nodules, had superior maximum performance skills than their nonsinging counterparts.     

Vocal fold nodule vs. vocal fold polyp: answer from surgical pathologist and voice pathologist point of view

Vocal fold polyps and nodules are caused by inflammation caused by stress or irritation. Our study involved looking retrospectively at 30 patients. A clinical diagnosis was established by an otolaryngologist and voice pathologist through videostroboscopic analysis. Histological sections after removal of the vocal fold lesion were available for microscopic examination. All of these cases have also been previously evaluated and photographed. A clinical diagnosis of either a polyp or a laryngeal nodule have been made and documented. Two pathologists made the histological evaluation separately initially unaware of the clinical diagnosis. Their impression was recorded. After the clinical diagnosis become available and comparison between the clinical and pathological diagnosis were made, a retrospective review of the tissue was attempted to reconcile the differences. In conclusion, after careful histological evaluation, no definitive histological distinction can be made between laryngeal nodules and polyps. Our data showed no distinction between the two entities when compared for the presence of edema, fibrin, inflammation, and amyloid-like material. A statistically significant difference was found in the size of the specimen and the presence of telangiectasias. Based on our data, a biopsy larger than 0.3 cm could be a polyp and a biopsy less than 0.3 cm could be a nodule.     

火焰原子吸收法测定大洋底锰结核中的铜,钴,镍,铁,锰

本文介绍了用火焰原子吸收法对大洋底锰结核中铜，镍，铁、锰中五种离子同时测定的方法。确定了仪器工作条件，并对共存元素及残留试剂的影响进行了研究。方法精密度和准确度令人满意。     

Aerodynamic, laryngoscopic, and perceptual-acoustic characteristics in dysphonic females with posterior glottal chinks: A retrospective study

The relationships of posterior glottal chink magnitude and nodule size with phonatory flow rate, resistance, and breathiness were investigated in 70 women in a retrospective study. Results demonstrated a strong relationship between chink size airflow, but no relationship between nodule size and airflow. Resistance and nodule size were moderately correlated. Breathiness was not explained by airflow, nodule size, or chink magnitude. Subjects in therapy demonstrated concurrent reductions in airflow and chink size. For the laryngeal magnitude measures, visual-perceptual ratings were compared with computer-based measurements. The discussion includes a critical analysis of measurement methods and directions for future research.     

Glottal opening in patients with vocal fold tissue changes

Synchronized videostroboscopy and electroglottography were applied to the measurement of anterior-to-posterior open glottal length in four groups of patients; two with no clinically significant voice disorder, one with vocal fold polyps, and one with vocal fold nodules. The data showed that the groups did not differ significantly when open glottal length was measured at the time of minimum glottal opening. The pathological groups had significantly lower open glottal length measurements, however, when measurements were obtained at the time that vocal fold contact was initiated during the glottal cycle. The findings are preliminary evidence that vocal fold neoplasms may not have the effect of reducing glottal closure, as previously suggested in the literature. The data also highlight the importance of examining differential effects of vocal fold neoplasms at various points throughout the glottal cycle.