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Hunting strategy of a generalist ant species proposed as a biological control agent against termites
(Kluwer Academic Publishers., 1999-09) Kenne, Martin; Schatz, Bertrand; Durand, Jean-Luc; Dejean, Alain
We studied the hunting behaviour of Myrmicaria opaciventris (Hymenoptera: Formicidae) in order to evaluate if it can be used as a biological control agent against the termites that damage sugarcane plantations. Hunting workers foraged in groups and recruited nestmates at short-range when they encountered large termite soldiers or groups of small termite workers. Differences in prey capture concerned the: (1) means of detection (from a distance or by contact); (2) termite body part seized (small termites seized by the body; large termites by an appendage); (3) percentages of prey abandoned; and (4) use of venom. The sting of the workers is spatulated implying a topical application of the venom on the prey. Large termites were stretched by several workers whose adherence to the substrate is facilitated by well-developed arolia and claws on the legs while others spread venom on the body and carved it up. An adaptation to termite capture was noted with a distribution of tasks between the workers which subdued prey, and those which transported it. In the former case, the workers easily eliminated termite soldiers, successively attacked several termite workers and even captured new individuals while holding the first ones captured between their mandibles before retrieving them all at once. The remaining individuals were retrieved by the transporting workers. Given this particularly effective predatory strategy, we concluded that, under certain conditions, M. opaciventris can be used as a biological control agent against termites.
TERMITES: BIOLOGY, PREVENTION, AND CONTROL
(washington state university, 2002) . Antonelli, Arthur L
Approaches to Biological Control of Termites
(University of Hawaiʻi at Mānoa, 2003-01) Grace, J. Kenneth
Biological control refers to the application or manipulation of preda- tors, parasitoids, or pathogens in order to suppress and manage insect populations. The cryptic habits of subterranean termites limit their susceptibility to predators. Ants are generally considered to be the most effective predators of termites, and under some conditions may be able to exclude them from occupying feeding sites at the soil surface. However, ants are not able to penetrate far into the subterranean gallery system. To date, there is very little documentation of termite parasitism. Thus, the most promising area of biological control research with termites appears to lie with pathogens. Unfortunately, termite social and chemical defenses appear to be strong limiting factors in inhibiting disease outbreaks in termite colonies. Fungi and nematodes have received the greatest attention to date, and a few commercial formula- tions are either available or on the near horizon, but their field efficacy is not well documented. Bacteria are also currently of interest, and manipulation via molecular techniques may be a viable path to devel- opment of efficient microbial agents. Other approaches to enhancing the efficacy of microbial agents may be the use of combinations of pathogens, or insecticide plus pathogen combinations. Microbial con- trol is a balancing act, in that pathogens must not be repellent, and must not have such rapid or dramatic effects upon the infected individuals that others will subsequently avoid contact with them or with the inoculum source. On the other hand, they must be capable of distribution through the colony and induction of either an epizootic or sufficient delayed mortality to essentially destroy the colony. A self- replicating time bomb, akin to a computer virus, would be the ideal microbial control agent.
Jail Incarceration and Birth Outcomes
(2004) Bell, Janice F.; Zimmerman, Frederick J.; Cawthon, Mary L.; Huebner, Colleen E.; Ward, Deborah H.; Schroeder, Carole A.
This study examined the relationships between jail incarceration during pregnancy and infant birth weight, preterm birth, and fetal growth restriction. We used multivariate regression analyses to compare outcomes for 496 births to women who were in jail for part of pregnancy with 4,960 Medicaid-funded births as matched community controls. After adjusting for potential confounding variables, the relationship between jail incarceration and birth outcomes was modified by maternal age. Relative to controls, women incarcerated during pregnancy had progressively higher odds of low birth weight and preterm birth through age 39 years; conversely, jail detainees older than 39 years were less likely than controls to experience low birth weight or preterm birth. For women in jail at all ages, postrelease maternity case management was associated with decreased odds of low birth weight, whereas prenatal care was associated with decreased odds of preterm birth. Local jails are important sites for public health intervention. Efforts to ensure that all pregnant women released from jail have access to enhanced prenatal health services may improve perinatal outcomes for this group of particularly vulnerable women and infants.
Microscopy and outpatient malaria case managementamong older children and adults in Kenya
(Published online in Wiley InterScience (www.interscience.wiley.com), 2006-04) Zurovac, D; Midia, B; Ochola, S . A; English, M; Snow, R. W
To evaluate the accuracy of routine malaria microscopy, and appropriate use andinterpretation of malaria slides under operational conditions in Kenya.methods Cross-sectional survey, using a range of quality of care assessment tools, at governmentfacilities with malaria microscopy in two Kenyan districts of different intensity of malaria transmission.All patients older than 5 years presenting to outpatient departments were enrolled. Two expertmicroscopists assessed the accuracy of the routine malaria slide results.results We analysed 359 consultations performed by 31 clinicians at 17 facilities. Clinical assessmentwas suboptimal. Blood slide microscopy was performed for 72.7% of patients, who represented 78.5%of febrile patients and 51.3% of afebrile patients. About 95.5% of patients with a positive malariamicroscopy result and 79.3% of patients with a negative result received antimalarial treatment.Sulphadoxine–pyremethamine monotherapy was more commonly prescribed for patients with anegative test result (60.7%) than for patients with a positive result (32.4%). Conversely, amodiaquine orquinine were prescribed for only 14.7% of patients with a negative malaria microscopy result comparedto 57.7% of patients with a positive result. The prevalence of confirmed malaria was low in both high(10.0%) and low-(16.3%) transmission settings. Combining data from both settings, the sensitivity ofroutine microscopy was 68.6%; its specificity, 61.5%; its positive predictive value, 21.6% and itsnegative predictive value, 92.7%.conclusions The potential benefits of microscopy are currently not realised because of the poor qualityof routine testing and irrational clinical practices. Ambiguous clinical guidelines permitting treatment ofolder children and adults with a negative blood slide also undermine rational use of antimalarial drugs
TERMITE CONTROL
(Pesticide Regulation, 2007-04) Randall, Carolyn J.
Capacity Development for smallholder Irrigation in Kenya
(Published online in Wiley InterScience (www.interscience.wiley.com), 2008-05) Mati, Bancy M.
This paper presents the experiences on capacity development for irrigation in Kenya, drawing from a study of sevensmallholder irrigation schemes, namely: New Mutaro, Emening, Mitunguu, Ng’uuru Gakirwe, Lari, Mukuria-Kyambogo and Isiolo River Water Users Association. These schemes were selected for their apparent success inirrigation management, sustainability and poverty reduction among the beneficiaries. Although the seven schemeshad diverse innovations and enterprises, common drivers of success were identified as: (i) introduction of newknowledge/technology, (ii) availability of markets, (iii) good governance structures, (iv) funding for infras tructuredevelopment, and (v) targeted capacity development. It was also found that initial investment costs for smallholderirrigation schemes ranged from about US $198 to $1744 per ha, which is much lower than reported for large publicschemes. Generally, all the schemes had recorded im proved food security and incomes, with net earnings rangingfrom US $200 to $1200 per month for single-crop ente rprises. Capacity development had played a major role in thepositive performance of the schemes. However, the respective schemes had experienced different modes ofcapacity building, which included government extension services, NGOs, private sector, research institutes,out-grower support schemes and farmer-to-farmer learning. This paper focuses on the role of capacity develop-ment. Copyright # 2008 John Wiley & Sons, Ltd
The biological effectiveness of wood modified with linear chain carboxylic acid anhydrides against the subterranean termites Reticulitermes flavipes
(published online, 2008-06) Papadopoulos, Antonios N.; . Avtzis, Dimitrios N; Avtzis, Nikolaos D.
he work described in this paper has demon- strated that chemically modified Corsican pine sapwood with a homologous series of linear chain carboxylic acid anhydrides provided bioprotection against the subterranean termites Reticulitermes flavipes. By varying the reaction time, various levels of modifications were obtained. There was no significant reduction in feeding above 16% WPG (weight percent gain due to modification), suggesting that modification to WPGs greater than this did not offer addi- tional protection. The type of anhydride employed has little influence on resistance against termites.
Systematization of basic divergent integrals in perturbation theory and renormalization group functions
(Elsevier, 2009-02) Brito, L.C.T.; Fargnoli, H.G.; Scarpelli, A.P. Baêta; Sampaio, Marcos; Nemes, M.C.
We show that to n loop order the divergent content of a Feynman amplitude is spanned by a set of basic (logarithmically divergent) integrals I (i) log(λ2), i = 1, 2,...,n, λ being the renormalization group scale, which need not be evaluated. Only the coefficients of the basic divergent integrals are show to determine renormalization group functions. Relations between these coefficients of different loop orders are derived.
Chemistry in Second Life
(Springer Open, 2009-10) Lang, Andrew SID; Bradley, Jean-Claude
This review will focus on the current level on chemistry research, education, and visualization possible within the multi-user virtual environment of Second Life. We discuss how Second Life has been used as a platform for the interactive and collaborative visualization of data from molecules and proteins to spectra and experimental data. We then review how these visualizations can be scripted for immersive educational activities and real-life collaborative research. We also discuss the benefits of the social networking affordances of Second Life for both chemists and chemistry students.
Chemistry Central Journal
(Chemistry Central Journal, 2009-10) Lang, Andrew SID; Bradley, Jean-Claude
This review will focus on the current level on chemistry research, education, and visualization possible within the multi-user virtual environment of Second Life. We discuss how Second Life has been used as a platform for the interactive and collaborative visualization of data from molecules and proteins to spectra and experimental data. We then review how these visualizations can be scripted for immersive educational activities and real-life collaborative research. We also discuss the benefits of the social networking affordances of Second Life for both chemists and chemistry students
Uniqueness of moving boundary for a heat conduction problem with nonlinear interface conditions
(Elsevier, 2010-01) Wei, T.
In this paper, based on the maximum principle and the unique continuation theorem, we present a uniqueness result for a moving boundary of a heat problem in a multilayer medium with nonlinear interface conditions.
A New Adaptive EDCA Approach to QoS of Wireless Communications
(Scientific Research Publishing, 2010-07) Wang, Huibin; Hu, Yang; Zhang, Lili; Xia, Wei
Under the background of intelligent transportation application, QoS for various services is different in wireless com-munication. Based on the MAC layer protocol, this paper analyzes the QoS in IEEE 802.11 MAC protocol framework, and proposes a new design of a Differentiation Enhanced Adaptive EDCA (enhanced distribution channel access) approach. The proposed approach adjusts the window zooming dynamically according to the collision rate in sending data frames, makes random offset, and further distinguishes the competition parameters of the data frames that have the same priority, so as to reduce the conflict among the data frames, and improve the channel utilization. Experiments with different service cases were conducted. The simulation results show that: comparing with the conventional EDCA method, the proposed approach can ensure that high priority services are sent with priority, and the overall QoS is highly improved.
Sensor Placement to Improve the Positioning Performance Based on Angle of Arrival (AOA)
(Scientific Research Publishing, 2010-07) Omidali, Behzad; Shirazi, S. S.
In this paper, a method for sensor placement to improve the placement quality based on angle of arrival of signal in a specific area is proposed. The installation place of sensors may be constrained with specified boundaries. In this me-thod, the criterion of maximum quality of placement is the Cramer-Rao bound. The generalized pattern search as an effective method is used to maximize error bound of the placement problem by angle of arrival. Better results are ob-tained in comparison with results of genetic algorithm. The derived results are compared from two aspects of run time and result quality.
Cognitive Radio Sensing Using Hilbert Huang Transform
(Scientific Research Publishing, 2010-07) Narayanankutty, K. A.; A. Nair, Abhijith; Soori, Dilip; Pradeep, Deepak; Teja, V. Ravi; K.B., Vishnu
Vast segments of the frequency spectrum are reserved for primary (licensed) users. These legacy users often un-der-utilize their reserved spectrum thus causing bandwidth waste. The unlicensed (secondary) users can take advantage of this fact and exploit the spectral holes (vacant spectrum segments). Since spectrum occupancy is transient in nature it is imperative that the spectral holes are identified as fast as possible. To accomplish this, we propose a novel adaptive spectrum sensing procedure. This procedure scans a wideband spectrum using Hilbert Huang Transform and detects the spectral holes present in the spectrum.
A Perspective on Traffic Measurement Tools in Wireless Networks
(Scientific Research Publishing, 2010-07) Siddamallaiah, Ramesh B.; Subramanian, Gowrishankar; Satyanarayana, Piriyapatna S.
To understand the characteristics of the wireless networks, the network usage data from wireless measurement tools are essential. The data collection is a process of collecting the network time-varying information in standardized format and from standard interfaces. The characteristics include signal propagation, received signal quality, network traffic, active applications and mobility of the mobile terminal (MT). The purpose of the measurement is to collect vital data of the wireless network. There are several tools available for this purpose. The most widely used network measurement tools are client side measurement tool, Syslog, Simple Network Management protocol (SNMP), network sniffing, wireless sniffing. This paper discusses the different wireless measurement tools and their benefits and limitation these tools.
The Design of an Intelligent Security Access Control System Based on Fingerprint Sensor FPC1011C
(Scientific Research, 2010-07) Wang, Yan; Liu, Hongli; Feng, Jun
This paper deals with the design of an intelligent access control system based on the fingerprint sensor FPC-1011C. The design uses the S3C2410 and TMS320VC5510A as the system processor. A fingerprint acquisi-tion module and a wireless alarm module were designed by using the fingerprint sensor FPC1011C and GPRS module SIM100 respectively. The whole system was implemented wireless alarm through messages and GPRS-Internet in the GSM/GPRS web. In order to achieve the simple and high Real-time system, the μC-Linux system migration was also implemented
Two Simple Analog Multiplier Based Linear VCOs Using a Single Current Feedback Op-Amp
(Scientific research, 2010-07) Bhaskar, Data R.; Senani, Raj; Singh, Abdhesh K.; Gupta, Shanti S.
Two simple voltage-controlled-oscillators(VCO) with linear tuning laws employing only a single current feedback operational amplifier (CFOA) in conjunction with two analog multipliers(AM) have been highlighted. The workability of the presented VCOs has been demonstrated by experimental results based upon AD844 type CFOAs and AD534 type AMs
WiMAX System Simulation and Performance Analysis under the Influence of Jamming
(Scientific Research Publishing, 2010-07) Jha, Rakesh; Patel, Hardik; Dalal, Upena D.; Vishal, Wankhede A.
This paper presents simulation of WiMAX based system under jamming. The performance of the system was found out to greatly differ with the use of different jamming signals, allowing central areas to be identified, where system devel-opment should be focused on. In addition, from the basic theory point of view, rather surprising results were also found. This work should give a clear picture of how the studied WiMAX system performs under jamming as well as without jamming. The results show that some forms of interference degrade the performance of the system rapidly, thus the form of incoming jamming should be known and considered before deploying the system. Single carrier jamming and multi–carrier jamming are discussed here. The issues related to jamming and jamming reduction techniques are also covered. Jamming can destroy communication in the targeted area. Multi–carrier jamming is challenge in WiMAX because WiMAX is having OFDM based physical layer. Simulation is the main approach in this paper. OPNET MODELER 14.5 is the software used for the simulation purpose.
The Performance Gain of Cognitive Radio in Adaptive Modulation Scheme
(Scientific Research Publishing, 2010-07) Foukalas, Fotis
Cognitive radio is considered as one of the main enablers for provisioning dynamic and flexible spectrum/channel allocation in wireless communications. The reliable data transmission over cognitive radio should employ modulation, coding etc. and thus the performance of such a new communication system should be realized. In this paper, we provide the performance analysis of adaptive modulation over a cognitive radio system in order to study the potential gain of cognitive radios in terms of spectral efficiency. The results obtained show that the performance gain of cognitive radio in adaptive modulation is remarkable.

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