Zoo soundscape: Daily variation of low-to-high-frequency sounds

Most studies assessing the impact of noises on zoo animal welfare did not measure sound frequencies outside of the human-hearing range (infrasounds and ultrasounds). Many nonhuman mammals can hear these frequencies, and because loud and variable soundscapes are potentially detrimental for animal welfare, this overlooked aspect of their acoustic environment could have important consequences. This study evaluated the soundscape of an urban zoo in a large frequency range (17.5–90,510 Hz) by measuring its average sound levels (L_eq) and variability (the difference between highest and lowest peaks). Sound data were collected for 24 hr in 25 locations (e.g., indoor, outdoor, near the amusement park). The soundscape was not considered problematic for animal welfare when looking at the average sound levels in most locations (<77-dB sound pressure level [SPL]), except for a few indoor areas and near the water park. Ultrasounds were rare, had low average sound levels, and were less variable in time. Infrasounds were always present and were the loudest and most variable sound frequencies. The soundscape was louder and more variable during the day and when visitors were present, suggesting that human-related activities were the sources of these augmentations. Indoor environments were generally louder than outdoor environments and touristic features; however, the water park was near 85-dB SPL during the day. On the basis of results, we suggest a series of mitigation actions to minimize noise-related stress in captive animals.     

响应面法优化超声辅助提取太子参多糖工艺研究

本文探讨超声波作用下太子参多糖提取的最佳工艺条件。在单因素试验基础上,采用响应面法对太子参多糖提取工艺参数进行优化研究。响应面试验表明提取温度、提取时间和水料比对响应值多糖提取得率均有显著影响,优化得到太子参多糖超声提取最佳工艺条件为:提取温度为74℃;提取时间为65 min;水料比为26 mL/g;超声波功率100 W。在此条件下太子参多糖的提取得率为2.48%,与模型预测值非常接近。     

IDENTIFICATION OF BRITISH BAT SPECIES BY MULTIVARIATE ANALYSIS OF ECHOLOCATION CALL PARAMETERS

ABSTRACT

Previous studies have found variability and individual distinctiveness in the echolocation calls of bats. We consider two implications of individually distinct echolocation calls: 1) whether bats may be able to use such variation to recognise familiar conspecifics, and 2) whether investigators could use such variation to identify known individuals or to census populations. We compared the discriminability of the echolocation calls of big brown bats (Eptesicus fuscus) recorded in three situations: (a) while held in the hand, (b) while perched on a platform, and (c) while flying in an anechoic chamber. Using variables describing each sonar call, we employed discriminant function analysis (DFA) to assign calls to recording situation or to bat. Discrimination of calls by recording situation was largely unsuccessful, although flying calls could be distinguished from platform calls. Assignment of calls to individual bat across recording situations yielded 72% success, and, within a given recording situation, yielded 87% success. Stepwise DFA reduced the number of variables needed to discriminate between individuals with only a slight decrease in correct classification. These results suggest that bats (or researchers) may be able to use the information contained in the echolocation calls for individual recognition. Individual distinctiveness raises the possibility of censusing bats by sound. We used cluster analysis in an attempt to determine whether, given a sample of calls from an unknown number of bats, a reasonable estimate of the number of bats could be obtained. Results were unsatisfactory, suggesting that cluster analysis probably will not permit acoustic censusing of bats in the field.     

高强度聚焦超声在药物控制释放的应用及进展

高强度聚焦超声能够以一种非侵入性的方式有效地穿透身体内部组织,聚焦在深层组织中一个很小的空间区域内,产生很强的声能,这些能量被组织吸收引起局部温度的升高。当温度到达热敏脂质体的相变温度时,磷脂烷基链构象的会发生改变,导致脂质体的通透性增强,从而能够促进药物的释放。因此,高强度聚焦超声可以被用作外源刺激控制体内特定位置热敏脂质体的药物释放。本文对高强度聚焦超声在药物控制释放领域的应用及进展进行综述。     

晚期肝癌和复发性肝癌治疗的研究进展

肝细胞癌(HCC)是我国最常见的恶性肿瘤之一,70%继发于肝炎、肝硬变。虽然诊断技术的提高,使肝癌的早期发现成为可能,然而由于肝癌早期症状隐匿,大多数肝癌确诊时已处于中晚期。肝切除术是治疗肝细胞癌最常用的手段。对于一些不可切除的晚期肝细胞癌,可采用动脉化疗栓塞以及系统化疗等手段使肿瘤降期,当转变成可切除肝癌后,再行补救性肝切除延长患者的生存期。此外,对于剩余肝体积不足而无法行一期肝切除的患者,可以采用PVE、ALPPS等方法,在剩余肝脏体积增大后再行二期肝切除术。肝内肿瘤复发率高也是导致肝细胞癌预后差的重要因素。在局部治疗后,建议在保留肝功能的前提下重复治疗。相比局部消融和动脉化疗栓塞治疗等多种手段,肝切除术有最好的远期疗效。联合和重复不同的治疗手段可达到很好的总生存期。对于患有晚期不可切除肿瘤或复发癌的患者,应积极的发挥肝切除的作用,并联合其他非手术治疗手段以取得较好的预后。     

Simple combined explicit/implicit water model

A simple combined water model (SCW model) for the calculation of the hydration free energy is presented. In the frame of the model a solute is placed in the centre of the spherical cavity with explicit water molecules, which are considered at the atomistic level. Rigid wall potential at the boundary of the cavity restricts the moving of the explicit water molecules. Water outside the sphere is considered as the conducting continuum (implicit part of the model). Simulation is performed in the frame of the NVT ensemble (constant number of particles, volume and temperature), density of water is fixed and equal to experimental value 1 g/cm³. The energy of electrostatic interaction of atomic point charges of the explicit water molecules with conducting continuum is calculated analytically by means of the image charges method. It provides high computational efficiency of the SCW model. For the averaging of the calculated thermodynamic and structural values over microstates of the system the thermodynamic integration method is used. The possible using of SCW for the docking problem is discussed.     

基于频谱图像灰度共生矩阵的无损测温方法

本文提出了一种基于哈达玛变换的频谱图像灰度共生矩阵(Hadamard-GLCM)的高强度聚焦超声治疗无损测温方法。利用高强度聚焦超声辐照新鲜离体猪肉组织,获取辐照前后的B超图像的减影图像,采用Hadamard变换对其进行处理,获取频谱图像,将频谱图像的灰度共生矩阵惯性矩作为反应温度变化的信息参数。实验表明:不仅单组数据的Hadamard-GLCM惯性矩(HGMI)和温度能很好的线性拟合,而且多组数据的Hadamard-GLCM惯性矩与温度也成近似的线性关系,而且斜率非常接近,拟合度更接近1,误差小,对温度的分辨能力高,容错能力强,与传统的测温方法相比有着明显的优势,能为HIFU治疗过程中的无损测温提供有效的实时依据。