Micro-Arthropods in the Surroundings of Nests of Messor arenarius Ants in the Negev Desert in Israel

The present research investigated a segment of the micro-arthropod populations residing within nests of Messor arenarius ants in the Negev Desert of Israel. The total frequencies of micro-arthropods in the chaff of those ants’ nests were found to be higher than in the surrounding soil of the same nests. Acari (mites) were observed to be more abundant during the spring season, whereas their presence decreased during the summer months. Springtails (Collembola) were found to follow the Acari pattern, commonly found within the nests of those ants during spring but were absent during summer. Psocoptera order inhabiting soil habitats were infrequently encountered during spring, but their prevalence increased significantly during summer, particularly within the chaff of the ants’ nests, suggesting that chaff is their primary food source in the Negev Desert. Our research suggests that shifts in seasonality have important consequences on the distribution of soil invertebrate communities with implications on nutrient cycling.

The Effect of Selective Logging on the Nest Density, Foraging Range and Colony Size on the Ground-Dwelling Ant Aphaenogaster Swammerdami Forel, 1886 in Kirindy ForestmMadagascar

Studying the ecology of ants can be a powerful tool for conservation, While the effect of logging is mainly investigated by the comparison of species richness and composition, the impact on individual species are often neglected. This study investigated the effect of selective logging on the nest density, foraging range and colony size on the ground-dwelling ant Aphaenogaster swammerdami in Kirindy forest--Madagascar. This ant is a common ground-dwelling species in Kirindy, a western dry deciduous forest of Madagascar. Sampling was done in two sites of the forest： One part that was selectively lodged and another that have not been logged. Here we show that selective logging led to a decrease in colony size and density, while the foraging range seemed to be unaffected. Higher desiccation stress and lower food availability in the logged forest are most likely to be responsible for these results.

主动网络工具集ANTS的主动包格式分析

目前国内发表的一些论文上关于ANTS的主动包格式介绍的不是很清楚、甚至是有些出入 ,而国外的有关文献中也没有相关内容的详细介绍。本文介绍了通过在搭建的ANTS主动网络平台上运行主动Ping命令 ,而后捕获该主动Ping数据包进行分析的方法 ,得出了ANTS的主动包 (封装体 )详细格式。

基于ANTS的主动路由支撑框架的设计与实现

在主动网工具包ANTS的基础上实现了一个QCAR原型系统,通过拓展ANTS的框架结构使其支持主动路由服务和沿途的QoS保障,并在该框架的基础上给出了一个主动路由的应用TraceRtApplication,通过具体的主动路由示例程序的实施,说明了如何在QCAR系统上开发新的应用。该文的研究和实现证明,与传统网络相比,在主动网基础上通过向网络中注入用户定制的、面向应用的路由需求代码,可以方便地实现主动路由定制和QoS保障。

主动网络执行环境ANTS的扩展设计及应用研究

由于国内在主动网络操作系统和执行环境方面的研究的薄弱,主动网络的应用研究受到了一定影响。基于该现状的考虑,分析了ANTS主动网络执行环境的优势与不足,针对其不足设计开发了一种构建灵活、能满足多种移动代码加载机制的执行环境EANTS,最后利用该平台进行了主动网络的管理应用研究,并实现了主动网络管理原型系统,研究成果为进一步进行主动网络应用研究提供了一种可选择的平台。

基于AntStream用户聚类的协同过滤推荐系统

系统规模的逐步扩大和用户兴趣的发展变化给传统协同过滤推荐系统带来了实时性减弱和准确性降低的问题。基于K-Means用户聚类的协同过滤技术虽然能在一定程度上解决这两个问题,算法本身却带有局部最优的缺陷。在保证实时性的前提下,为克服K-Means算法的缺陷,提出使用AntClass蚁群算法对用户聚类。同时提出将用户评分看作数据流,利用金字塔时间框架预处理数据,从而体现用户兴趣随时间的变化。于是,将AntClass蚁群算法和利用金字塔时间框架预处理过的数据流相结合,最终形成文中的AntStream算法。实验表明,AntStream算法不仅改善了传统协同过滤推荐系统的实时性问题,而且更大程度提高了推荐质量。

鲤鱼(Cyprinuscarpio,Cyprinidae)ants基因及其对鳞片发育的影响

ants(adenine nucleotide translocators),又称为ATP/ADP载体,利用Genefishing差异筛选技术对普通鲤鱼和德国镜鲤的皮肤转录产物进行筛选,得到了其中一个ant基因的部分片段,利用RT-PCR技术对皮肤中的ants基因进行钓取,得到6种不同的CDS序列。利用CLUSTALW对这6条翻译后的序列进行比对,发现这6条序列编码4种不同的氨基酸序列,表明ants基因至少有6种不同的转录产物(isoforms),但是在蛋白质水平上可能存在4种不同的翻译产物。利用NCBI上的blast对氨基酸序列进行同源性检索发现这4个蛋白产物与斑马鱼ant2最为相似,其相似度分别达到97%,97%,96%,98%。对处于不同分类地位的物种的ants基因与鲤鱼的4个ants表达产物进行进化树分析发现,这4个蛋白产物在93/100再现性水平上明显聚类为ant2,说明皮肤中表达的这些ants基因很可能是ant2。原位杂交结果显示,ant2在受精后4.5 h和6 h不表达,从受精后10 h开始在外包处强烈特异表达,在受精后12 h的胚胎中很弱表达,在受精后24 h的体节中特异强烈表达,在受精后48 h胚胎无表达,但是在着生鳞片的部位特异强烈表达,而在皮肤的其他部位则表达较弱或者不表达。以上的结果表明,ant2基因可能是通过不同的转录产物在精细调控鳞片的发育。

一种针对频率分配问题的改进ANTS算法

频率分配问题是近年来通信领域研究的热点。针对FAP问题提出了一种结合模拟退火算法的改进ANTS算法。运用模拟退火算法产生次优解,利用次优解分配初始信息素,并利用ANTS算法来寻求最佳方案。在ANTS算法的每个蚂蚁寻找局部最优过程中,为了加快运算速度,对局部寻优过程进行了改进。实验结果表明,在解质量相当的情况下,该算法能够大大地加快收敛速度,特别是针对一些较复杂的分配情况,效果明显。

Finding the Minimum Ratio Traveling Salesman Tour by Artificial Ants

Ants of artificial colony are able to generate good solutions to the famous traveling salesman problem (TSP). We propose an artificial ants algorithm for solving the minimum ratio TSP, which is more general than the standard TSP in combinatorial optimization area. In the minimum ratio TSP, another criterion concerning each edge is added, that is, the traveling salesman can have a benefit if he travels from one city to another. The objective is to minimize the ratio between total costs or distances and total benefits. The idea of this type of optimization is in some sense quite similar to that of traditional cost-benefit analysis in management science. Computational results substantiate the solution quality and efficiency of the algorithm.

A Survey on the Vehicle Routing Problem and Its Variants

In this paper, we have conducted a literature review on the recent developments and publications involving the vehicle routing problem and its variants, namely vehicle routing problem with time windows (VRPTW) and the capacitated vehicle routing problem (CVRP) and also their variants. The VRP is classified as an NP-hard problem. Hence, the use of exact optimization methods may be difficult to solve these problems in acceptable CPU times, when the problem involves real-world data sets that are very large. The vehicle routing problem comes under combinatorial problem. Hence, to get solutions in determining routes which are realistic and very close to the optimal solution, we use heuristics and meta-heuristics. In this paper we discuss the various exact methods and the heuristics and meta-heuristics used to solve the VRP and its variants.

Response of ants to grazing disturbance at the central Monte Desert of Argentina: community descriptors and functional group scheme

Livestock ranching is one of the main productive activities in arid regions of the world.Grazing produces changes in animal as well as plant communities(e.g.richness,abundance and species dominance relationships).Ants are good biological indicators due to the environmental fidelity of some of their community parameters.We described the functional structure of the ant community in the central Monte of Mendoza,Argentina,and examined the effect of grazing using richness,diversity and the functional group scheme.We used pitfall traps to sample ants at a reserve with 30-year cattle exclusion and at an adjacent ranch.Eleven of the 27 recorded species showed significant differences in their abundance and two species were absent at the ranch.While richness and diversity did not reflect these differences,functional groups did.Hot Climate Specialists were more abundant at the ranch while Cryptic Species and Generalized Myrmicinae increased at the reserve.This study supports the utility of the functional group scheme to study the effects of grazing disturbance in ant communities of arid regions.

Plant community dynamics in arid lands: the role of desert ants

Ants (Formicidae, Hymenoptera) play an important role in seed bank, seedling establishment andplant composition of arid ecosystems. Thus, knowing plant-ant interaction provides useful information formanagers to design restoration and conservation plans. In this study, the roles of desert harvester ants (Messorintermedius and Messor melancholicus) and scavenger ants (Cataglyphis nodus and Lepisiota semenovi) on plantcommunities were investigated in arid ecosystems of southeastern Iran. Two vegetation types weredistinguished in the study area and the nest density of ant species was determined. Furthermore, plantcomposition and soil seed bank were estimated at different distances from the ant nests. Results showed thatthe density of M. intermedius and M. melancholicus nests was higher in dwarf shrub-shrub vegetation type and thedensity of C. nodus and L. semenovi nests was higher in dwarf shrub vegetation type. The harvester and scavengerants had enhanced the seed bank to 55% and 70%, respectively. Therefore, the role of scavenger ants on theplant communities' seed bank was greater than that of harvester ants. Although the scavenger ants were moreinfluential on the annuals and the invasive plant species, the radius impact of the harvester ants on theperennials was greater, i.e., a positive interaction existed between the perennial plants and the harvester ants. C.nodus and L. semenovi played an important role in enhancing the ecosystem's potential for restoration throughestablishment of pioneer species in early stage of succession. The activity of M. intermedius is crucial for thedevelopment and maintenance of climax plant communities in arid ecosystems through assisting the plantspecies' establishment in late stage of succession. It is essential to preserve the diversity of these key ant speciesfor the maintenance and sustainability of shrubs in arid ecosystems.

Toxicity and Efficacy of Two Emulsifiable Concentrates of 2-Tridecanone against Red Imported Fire Ants

2-tridecanone is a major constitute of defensive secretion in tawny crazy ants, Nylanderia fulva that is an ant species reported to be able to displace red imported fire ants, Solenopsis invicta in the field. 2-tridecanone was proven to be toxic to S. invicta. Although 2-tridecanone is commercially available, utilization of this naturally occurring compound in fire ant management has received little attention. In this study, toxicity and efficacy of two 2-tridecanone formulations were assessed against S. invicta. Two emulsifiable concentrates were prepared using 2-tridecanone as an active ingredient, vegetable oil as a solvent and polyoxyethylene tridecyl ether as a surfactant. Piperonyl butoxide (PBO) was used as a synergist in one formulation. Both formulations showed significant toxicity in laboratory bioassays. In a field trial, at application rate of 5.28 mL/L and 14 days after mound drench treatment, 100% control was achieved for formulation with PBO and 90% control for the formulation without PBO. In conclusion, both formulations had significant efficacy against S. invicta. Due to the low mammalian toxicity of 2-tridecanone, no involvement of hazardous synthetic organic solvents, no phytotoxicity at applied concentrations, and relatively low cost, both formulations are promising alternatives to commercial insecticide products for fire ant mound drench. The outstanding efficacy of both formulations observed in this study warrants further research on their efficacy against other pest insects.

Lipids and Fatty Acid Composition of Dried Edible Red and Black Ants

Total lipid contents,lipid classes and fatty acid compositions of hot-air dried edible black ants（Polyrhachis vicina Roger） from Wenzhou and Guizhou,China,and edible red ant（Oecophylla smaragdina Fabricius） from Thailand were determined.The major lipid components were triacylglycerol（43.4-79.4% of total lipid）,followed by phospholipids（6.1-21.5%）,diacylglycerol（6.1-18.1%） and cholesterol ester（4.9-13.5%） while free fatty acids（1.8-2.9%） and sterol（0.5-0.8%） were the minor components.Oleic acid（C18：1） was the most predominant fatty acid,accounting for 3 407.8,9 098.8 and 3 790.1 mg 100 g-1 in Wenzhou and Guizhou black ants,and Thai red ant,respectively.Followed by palmitic acid（C16：0）,922.9,2 523.3 and 1 511.8 mg 100 g-1;linoleic acid（C18：2n-6）,133.7,305.2 and 506.4 mg 100 g-1;α-linolenic acid（C18：3n-3）,35.1,138.0 and 52.5 mg 100 g-1;eicosapentaenoic acid（C20：5n-3） was 19.1,15.0 and 20.0 mg 100 g-1 in Wenzhou and Guizhou black ants,and Thai red ant,respectively.Docosapentaenoic acid（C22：5n-3） was only found in black ants,7.0 and 7.3 mg 100 g-1 for Wenzhou and Guizhou ants,respectively.The edible black and red ants were shown to be a good source of unsaturated fatty acid.

COMPOSITION ANALYSIS AND RESEARCH DEVELOPMENT OF NORTHERN FOREST ANTS

The compositions of two kinds of ants (Formica cunicu Laria and Polyrhachis vicina Roger) were determined with modern apparatuses. The result was that content of crude protein, fat, vitamin E, formic acid were 43.95%, 22.90%, 15.61 mg / Kg, 4.2% respectively forFormica cunicu Laria, and 42.56%, 21 .90%, 131 .2 mg / Kg, 3.8% respectively for Polyrhachlk vicina Roger.

Enhanced ants system and its application

NP-hard combinational optimization problem is not solved very well until now. One enhanced ants system based on ants system is advanced after analysis of the deficiencies of existing ants systems. Some improvements are made in state transfer rule and local modification rule. Furthermore, the enhanced ants system can solve NP-hard combinational optimization problem with restraints and condition path. The successful application of TSP problem and transportation net problem indicates that the proposed system has stronger function and higher efficiency than the original system.

Effects of Precipitation and Livestock Grazing on Foliage Foraging Ants in a Chihuahuan Desert Grassland

We examined the relationship between seasonal livestock grazing (late summer and late winter) and the abundance of two ant species, Dorymyrmex insana and Forelius pruniosus, on three types of plants (mesquite shrubs, snakeweed sub-shrubs, and mixed grasses) dominated by black grama (Bouteloua eriopoda). Stocking rates were adjusted to remove 75% of the available forage. Since Chihuahuan Desert grasslands are not in transition to shrublands, the grasses and some herbaceous plants are the only available forage. We hypothesized that neither rainfall nor cattle grazing would affect the abundance of these ants on mesquite (Prosipis glandulosa) or snakeweed (Gutierrezia sarothrae). Linear regressions of monsoon rainfall on mesquite (Prosopis glandulosa) produced an r2 nearly equal to that with the annual precipitation. Monsoon rainfall on the evergreen sub-shrub, Gutierrezia sarothrae, resulted in June-July rainfall accounting for 47% - 83% of the variation in densities of D. insana on snakeweed. The number of D. insana was more than double the number of F. pruinosus on grasses, mesquite, and snakeweed. There were significant reductions in the abundance of F. pruinosus on the grass in the grazed plots;each year the plots were grazed. There were no significant effects of grazing on the abundance of either of the ant species sampled from G. sarothrae canopies. There were significantly fewer D. insana on mesquite in summer grazed plots than on P. glandulosa in winter grazed and ungrazed plots in the second and third years of grazing. Pre-grazing effects were compromised by the high annual (more than double) precipitation.

Attractivity or Repellence: Relation between the Endophytic Fungi of <i>Acalypha</i>, <i>Colocasia</i>and the Leaf-Cutting Ants—<i>Atta sexdens</i>

Symbiotic relations are present in the nature and can contribute to the success of the organisms involved. Endophytic fungi live within the leaf tissues without causing any harm to the host plant, and some of them can be a defense mechanism against the attack by the leaf-cutting ants. Ants of the genus Atta are known as leaf-cutting ants and have an obligatory association with the fungus Leucoagaricus gongylophorus, cutting pieces of leaves and bringing them back to the colony to the fungus. The present study aimed to find out the endophytic fungi community of an attractive plant (Acalypha wilkesiana) and a less attractive plant (Colocasia esculenta) to the ants Atta sexdens. We found out that the communities are different in quantity and in composition and 73% of the isolated fungi were from A. wilkesiana, which has fungi known as attractive to leaf-cutting ants, such as genus Colletotrichum, Pestalotiopsis, Phomopsis and Xylaria. On the other hand, in C. esculenta, there was found the genus Fusarium, known to be reject by the leaf-cutting ants, and less fungal diversity than in the attractive plant A. wilkesiana. Therefore, our data suggest that attractivity or repelence of a plant to the leaf-cutting ants could be related to presence or ausence of determinated fungi more than the quantity of fungi present in a leaf.

Ants Assemblage Method According to an Age Gradient of Mango Orchards in Korhogo (C&ocirc;te d’Ivoire)

This study was conducted in the Korhogo region in an age gradient of mango orchards. The goal was to assess diversity and determine the influence of the environment on the composition of these organisms. Sampling was done using pitfall traps, threshing and manual collection. A total of 82 ant species were sampled on all plots. The cultivated plots are richer in ant species than the natural environment. Of the three (3) sampling methods, the Manual Collection proved to be more efficient (eff = 79.52%), followed by threshing (eff = 75.15%) and finally the least effective trap pit (eff = 73.39%). The number of individuals of the species varies according to the environment. The highest value was obtained in the young plot (485 individuals), followed by the intermediate plot (478 individuals), then the older plot (426 individuals) and finally the control plot (320 individuals). The species Camponotus acvapimensis was harvested mainly with 159 individuals. On the other hand, the species Lepisiota sp.1;Camponotus rufigenis, Camponotus sericeus and Oecophylla longinoda were specifically harvested in the control, young, intermediate and aged plots, respectively.

Utilizing Colored Pheromones and Helping Ants for Wireless Mesh Networks Routing

Improving routing algorithm performance not only leads to appreciate the quality of data transmission, but also increases the speed of data transfer. In this paper we propose a hybrid method which is a combination of traffic classification by the help of colored pheromones and helping ants method in the intermediate nodes. This combination increases the convergence speed and decreases the delay and Jitter in the network. Also we compare the obtained results with two known routing algorithms that are based on the ant colony.