The effect of pup vocalisations on food allocation in a cooperative mammal, the meerkat (Suricata suricatta)

In the meerkat (Suricata suricatta), a cooperative mongoose, pups follow potential feeders while the group is foraging and emit incessant calls when soliciting food from them. In contrast to a ’stationary’ brood of chicks, in which nestlings are fed at a fixed location, meerkat pups are ’mobile’ and become spread out. The question arises whether meerkat pups that experience different constraints to those facing chicks have evolved similar begging strategies. This paper describes the vocalisations that meerkat pups emit in the context of begging and investigates the influence of these calls on food allocation by older group members and on the behaviour of littermates. Meerkat pups use two types of calls when soliciting food from a potential feeder. The most common is a ’repeat’ call, which pups emit continuously when following an older forager over several hours a day. In addition, when a potential feeder finds a prey item, the pups next to it emit a bout of calls with increased calling rate, amplitude and fundamental frequency, termed ’high-pitched’ calls. Observations, together with playback experiments, showed that more prey was allocated to pups that called longer and more intensely. The pup closest to a feeder was almost always fed. The probability of emitting high-pitched calls did not depend on the time since a pup had received food, and the change from repeat to high-pitched calls occurred suddenly. The main function of the high-pitched call, therefore, does not appear to be to signal a pup’s hunger state. More likely, the two calls, in the context of begging, may be an adaptation to energetic constraints in a mobile feeding system. Pups, which are dispersed during foraging, may emit repeat calls over long periods to prevent potential feeders from eating all the prey themselves. At the moment a potential feeder finds prey, pups may give the more intense high-pitched calls to direct feeders to bring the food item to them and not to a littermate. Therefore, unlike the stationary feeding system where chicks emit one type of begging call when the feeder approaches the nest, meerkats, with a mobile feeding system, have evolved two discrete types of vocalisations in the context of begging. Received: 22 November 1999 / Revised: 1 July 2000 / Accepted: 17 July 2000     

Distribution and transport characteristics of fine particulate matter in beijing with mobile lidar measurements from 2015 to 2018

Accurately quantifying the concentration and transport flux of atmospheric fine particulate matter(PM_2.5) is vital when attempting to thoroughly identify the pollution formation mechanism.In this study,the mobile lidar measurements in Beijing on heavily polluted days in December from 2015 to 2018 are presented.The lidar was mounted on a vehicle,which could perform measurements along designated routes.On the basis of mobile lidar measurements along closed circuits of the 6 th Ring Road...     

Wayfinding with a GPS-based mobile navigation system: A comparison with maps and direct experience

This study examined the effectiveness of a Global Positioning System (GPS)-based mobile navigation system in comparison to paper maps and direct experience of routes, by focusing on the user's wayfinding behavior and acquired spatial knowledge. Based on information received from one of these three media, participants walked six routes finding the way to goals. Results showed that GPS users traveled longer distances and made more stops during the walk than map users and direct-experience participants. Also, GPS users traveled more slowly, made larger direction errors, drew sketch maps with poorer topological accuracy, and rated wayfinding tasks as more difficult than direct-experience participants. Characteristics of navigation with these three learning media and possible reasons for the ineffectiveness of the GPS-based navigation system are discussed.     

基于实时嵌入式操作的移动环境监测系统

利用面向对象技术、多线程技术和动态链接技术在嵌入式操作Windows CE上开发了移动环境监测系统。介绍了基于实时嵌入式操作的移动环境监测系统的设计原理、系统框架及关键技术。指出在嵌入式计算机上实现移动环境监测，既可以进行在线环境监测，也可以减少开发的费用和硬件投资。该系统的特点是集成度高，体积小，反应速度快，智能化高，稳定性好和可靠性强。     

移动通信基站电磁辐射污染分析及对策

移动通信基站发射天线产生的电磁波对环境造成电磁辐射污染，通过对沈阳移动通信公司部分基站产生的电磁辐射强度的测试，摸清了污染特点及规律，为今后环境管理规范化提供重要依据．     

EEG bioeffects on cochlear deaf from cellular phones

Objectives This paper aims to provide evidence of an inductive electromagnetic bioeffect on the human brain, which is independent from sound waves and produced by mobile phones, in proximal field, through correlating the EEG data obtained from electrodes placed on both normal and cochlear deaf individuals. Methods Two groups of subjects are placed under controlled electromagnetic conditions inside a Faraday chamber, 12 healthy and another 12 suffering from cochlear deafness). Each is sitting on a chair, fitted with additional support, and holding a cellular phone 2 cm away form the right auricular, in order to avoid a thermal effect as much as possible. All of them, relaxed and with their eyes closed, are EEG recorded in a basal state with their mobile phones off. Then, each of them is again recorded under the same conditions but with the mobile on and listening to the same conversation. In order to assess the observed EEG changes, a statistical analysis by means of the FFT (Fast Fourier Transform) was carried out. Results For both, healthy and cochlear deaf, assimilation or integration of the mobile phone signal by some electrodes is to be found. This is due to the increase of amplitudes for alpha and theta waves, whereas the signal is not integrated in other electrodes. By correlating the spectra of frequencies of corresponding EEG records for the same brain areas, we have not observed significative differences for both groups. Conclusions A possible electromagnetic direct inductive, non-thermal, bioeffect on the human brain is observed. This effect is produced by the use of mobile phones and it bears no relation to the sound waves.     

污染源普查后区域环境管理应用探讨

在第二次全国污染源普查的基础上,利用污染源普查期间配置的软硬件,开发市级区域环境污染源管理平台,进行污染源数据的年度更新,拓展污染源普查软件应用,实现环境管理及环境执法移动终端的应用。拓展二污普一张图的功能,利用移动客户端机动实时及地定位导航等为环境管理执法和环境突发事件应急处置提供技术支持。     

Characterization and recycling of polymeric components present in cell phones

The cell phone market is developing at a rapid speed. Today there are more than 1.6 billion consumers in the world, and the lifetime of a cell phone is less than 2 years. As a consequence, there is an increase in the waste associated to this product, and many alternatives to the disposal of the cell phones are being studied, such as recycling which shows to be the most important. It is crucial to know what materials constitute the cell phone in order to carry out recycling and determine environmental and economical issues. This work presents an evaluation of the cell phone components, characterizing the raw materials and some properties of the recycled materials.     

An experimental study on the effect of mobile phone conversation on drivers' reaction time in braking response

Introduction

This paper presents an experimental study in which the effect of three factors (distance between cars, mobile call duration, and time of driving (day or night)) on drivers' reaction time in braking response was investigated.

Methods

The experiment was performed in a real driving environment in which 27 male adults between the ages of 22 and 24 years participated. Three levels of the first two factors (i.e., distance between cars and call duration) and two levels of the last factor (i.e., time of driving) were selected to conduct the experimental study. A full factorial design of experiment with 18 treatment combinations and three replicates of each combination were used. Fifty-four trial runs were performed in a random manner and for each run drivers' reaction time in braking response was measured, which served the data for further analysis. Analysis of variance (ANOVA), interaction effect analysis, and various model adequacy tests were carried out using Design Expert software.

Results

The results of the study indicated that the most important factor affecting the drivers' reaction time in car braking response was the mobile call duration followed by the time of driving, with a high level of interaction between the two factors. It was also found that the distance between cars did not seem to have a significant effect on the reaction time in braking response. It is to be noted that these response times are expected to be higher under normal driving conditions where awareness of experimental environment is not present.

Impact on Industry

The findings of this study would help mobile phone industries in improving safety of mobile phone users in driving environment.     

Distractions and the risk of car crash injury: the effect of drivers' age

PROBLEM: Motor-vehicle accidents are one of the major causes of injury in most motorized countries. Driver distractions have been suggested as a contributor to traffic accidents. Moreover, age of the driver seems to have a role in the relationship between distractions and car crashes. But very few studies have investigated the effect of driver's age on this relationship. This exploratory study investigated the association between distractions, both inside and outside the vehicle, and the increased risk of car crash injury among drivers across different ages. METHOD: This study used a case series design to analyze data routinely collected by the NSW police in Australia. A special focus of this study was on how drivers' age affects the risk of car crash injury, which was determined by using a well-documented risk estimation methodology. RESULTS: The results obtained indicated that drivers of all ages, on the whole, are more susceptible to distractions inside the vehicle than distractions coming from outside. Age was shown to affect the relationship between in-vehicle distraction and the risk of car crash injury. A separate analysis was also conducted on hand-held phone usage while driving with results supplementing previous findings reported in the literature. IMPACT TO INDUSTRY: Safety strategies to countermeasure in-vehicle distractions have been suggested and discussed.