Degradation of the antiviral drug oseltamivir carboxylate in surface water samples

Numerous studies have documented that a wide number of pharmaceuticals used in human and veterinary medicine have the potential to enter the aquatic ecosystem. The antiviral prodrug oseltamivir phosphate has received recent attention with regard to its possible use against the highly pathogenic H5N1 virus. This preliminary laboratory study investigated the persistence of the active antiviral drug, oseltamivir carboxylate (OSC), in water samples taken from an irrigation canal. After an initial rapid decrease, OSC concentrations slowly decreased during the remaining incubation period. Approximately 65% of the initial OSC amount remained in water at the end of the 36-day incubation period. A small amount of OSC was lost both from sterilized water and from sterilized water/sediment samples, suggesting a significant role for microbial degradation. Stimulating microbial processes by the addition of sediments resulted in reduced OSC persistence. Presence of OSC (1.5?µg?mL^?1) did not significantly affect the metabolic potential of the water microbial population, estimated by glyphosate and metolachlor mineralization. In contrast, OSC caused an initial transient decrease in the size of the indigenous microbial population of water samples.     

Bird mating optimizer: An optimization algorithm inspired by bird mating strategies

Thanks to their simplicity and flexibility, evolutionary algorithms (EAs) have attracted significant attention to tackle complex optimization problems. The underlying idea behind all EAs is the same and they differ only in technical details. In this paper, we propose a novel version of EAs, bird mating optimizer (BMO), for continuous optimization problems which is inspired by mating strategies of bird species during mating season. BMO imitates the behavior of bird species metaphorically to breed broods with superior genes for designing optimum searching techniques. On a large set of unimodal and multimodal benchmark functions, BMO represents a competitive performance to other EAs.     

基于小波变换的适合Quick Bird遥感影像的融合方法

在分析了IHS变换、PCA变换、Brovey变换、加权融合、PMⅠ(Proposed methodⅠ)等一般融合方法的基础上,针对Quick Bird全色与多光谱影像的融合,提出了基于átrous小波变换的小波比值方法;然后通过目视判别、定量统计参数两种方法对各融合结果进行了比较.结果表明,小波分解层数为3的小波比值方法既很大程度地提高了空间纹理细节信息,又高度保持了原始多光谱影像的光谱特征,适合于Quick Bird遥感影像融合.     

多特征融合的鸟类物种识别方法

针对短时窗平均/长时窗平均算法从次声台站监测数据中提取的信号仍然包含噪声的问题,对支持向量机和人工神经网络的机器学习方法进行了研究。采用小波包分解的方法对信号进行重构,提取出各频带内的重构信号能量特征,对事件信号和噪声进行了识别实验,并分析了提高识别能力的方法,为工程应用提供理论参考。实验结果表明,在训练数据集不大的情况下,通过优化模型结构可以将两种方法的识别能力提高到可以接受的水平。     

Automatic bird sound detection in long real-field recordings: Applications and tools

The primary purpose for pursuing this research is to present a modular approach that enables reliable automatic bird species identification on the basis of their sound emissions in the field. A practical and complete computer-based framework is proposed to detect and time-stamp particular bird species in continuous real field recordings. Acoustic detection of avian sounds can be used for the automatized monitoring of multiple bird taxa and querying in long-term recordings for species of interest for researchers, conservation practitioners, and decision makers, such as environmental indicator taxa and threatened species. This work describes two novel procedures and offers an open modular framework that detects and time-stamps online calls and songs of target bird species and is fast enough to report results in reasonable time for non-processed field recordings of many thousands files and is generic enough to accommodate any species. The framework is evaluated on two large corpora of real field data, targeting the calls and songs of American Robin Turdus migratorius, a Northamerican oscine passerine (true songbird) and the Common Kingfisher Alcedo atthis, a non-passerine species with a wide distribution throughout Eurasia and North Africa. With the aim of promoting the widespread use of digital autonomous recording units (ARUs) and species recognition technologies the processing code and a large corpus of audio recordings is provided in order to enable other researchers to perform and assess comparative experiments.     

Multiple-physiological benefits of bird’s nest fern (Asplenium australasicum) frond extract for dermatological applications

p-coumaric acid and fucose-rich polysaccharide have been studied for many bio-functions in skin including cutaneous protection from oxidative damage and antiageing, respectively, as well as wound healing. The physiological activities of various bird’s nest fern extracts (BNFE), containing considerable fucose-rich mucilage and p-coumaric acid, on fibroblast and human skin were first investigated. BNFE with higher polysaccharide content generally contributed to a better moisture holding capability. Furthermore, BNFE showed pronouncedly enhancing effect on collagen production and growth of fibroblast (NIH-3T3), clinical trial results revealed that the emulsions with 1% BNFE showed good moisturising effect and improved the elasticity of human skins effectively. The potential of BNFE for cosmetics and medical applications such as natural moisturiser, antiageing and wound repairing was possibly related to the fucose-rich mucilage and various phenolic compounds including p-coumaric acid in BNFE.     

Calorimetric investigations on mound-building birds

Megapodes, and mound-building birds of the Pacific, incubate their eggs underground where the heat is supplied by organic decomposition, solar radiation, or geothermal sources. The incubation biology of the Australian mound builders has been examined from the standpoints of (1) the energetic requirements of malleefowl (Leipoa ocellata) to construct and maintain incubation mounds and (2) the physics, physiology, and behavior concerning mound thermoregulation of the brush turkey (Alectura lathami).

The energetic cost of mound tending in malleefowl is estimated by indirect calorimetry. The power required for digging into the mound to reach the eggs is approximately 20 W, or 3.8 times the basal metabolic rate of the bird. About 850 kg of sand has to be removed and replaced on the mound every time it is opened, a task requiring about 5 h. The overall energy investment for incubation for the entire 9 month season is 2.5 times that expected in similarly sized birds.

Brush turkey mounds become homeothermic because of (1) the high thermal inertia of their 3–11 t mass and (2) a stable equilibrium that is reached between heat production and heat loss. The mound tends to seek the equilibrium, but the bird adjusts the temperature by subtle manipulation of the mound. At an equilibrium temperature of 33°C, the mound produces about 110 W. Empirical data from natural mounds, set in the context of a numerical model of heat production and heat flux in the mound, indicate that equilibrium temperature is extremely sensitive to ambient temperature and mound size, but not water content. Wet or dry mounds can maintain appropriate incubation temperature, but the dry ones have low thermal conductivity, retain the heat well, and minimize the amount of forest litter collected during the incubation season.     

声场聚焦在数字语音驱鸟器阵列中的应用

鸟害已成为某些农作物的主要经济损失,为了提高数字语音驱鸟器驱赶害鸟的效果,本文给出了数字语音驱鸟器阵列系统设计和声音链声场聚焦实现方法,并详细说明了硬件电路的实现。阐述了声场聚焦的原理,通过调整声音链阵列加权实现了声场聚焦,达到预期效果。     

Modeling the spread of bird flu and predicting outbreak diversity

Avian influenza, commonly known as bird flu, is an epidemic caused by H5N1 virus that primarily affects birds like chickens, wild water birds, etc. On rare occasions, these can infect other species including pigs and humans. In the span of less than a year, the lethal strain of bird flu is spreading very fast across the globe mainly in South East Asia, parts of Central Asia, Africa and Europe. In order to study the patterns of spread of epidemic, we made an investigation of outbreaks of the epidemic in one week, that is from February 13–18, 2006, when the deadly virus surfaced in India. We have designed a statistical transmission model of bird flu taking into account the factors that affect the epidemic transmission such as source of infection, social and natural factors and various control measures are suggested. For modeling the general intensity coefficient f(r), we have implemented the recent ideas given in the article Fitting the Bill, Nature [R. Howlett, Fitting the bill, Nature 439 (2006) 402], which describes the geographical spread of epidemics due to transportation of poultry products. Our aim is to study the spread of avian influenza, both in time and space, to gain a better understanding of transmission mechanism. Our model yields satisfactory results as evidenced by the simulations and may be used for the prediction of future situations of epidemic for longer periods. We utilize real data at these various scales and our model allows one to generalize our predictions and make better suggestions for the control of this epidemic.