Influence of temperature on host location and multisensory orientation in the parasitoid Pimpla turionellae (L.) (Hymenoptera)

The ichneumonid wasp Pimpla turionellae (L.) (Hymenoptera) is a specialist parasitoid of lepidopteran pupae, and has to overcome the challenge of reduced chemical and visual cues as pupae are immobile, do not feed and do not emit excrements. Certain hymenopteran species have developed a particular mechanosensory mechanism in order to locate hosts hidden in hollow spaces inside of plant material (Broad & Quicke 2000). Similar to echolocation they use self-produced vibrations, instead of sounds, that are transmitted by the antennae onto the substrate. In analogous way to acoustics, this mechanosensory mechanism is referred to as vibrational sounding (Wäckers & al. 1998). Thermal dependence is well known in acoustical and vibrational communication of arthropods (e.g. Pires & Hoy 1992, Shimizu & Barth 1996) and is likewise presumed to affect mechanosensory host location by vibrational sounding. The species P. turionellae has recently been found to use vibrational sounding successfully in a temperature range from 8 to 28°C, but with less performance of searching behaviour and an adjusted signal production at extreme temperatures (Kroder & al. 2006, & al. 2007b, Samietz & al. 2006). Many insects have evolved strategies to maintain a balance of body temperature by ecto- and endothermic means. Raising and maintaining body temperatures above the ambient environment by endothermic means is particularly known in several hymenopteran species (Heinrich 1993). In the case of a thermally influenced host location mechanism, such means of thermoregulation could be supposed as well in order to maintain performance with changing temperatures. The study elucidates if the wasps are able to regulate their body temperature at suboptimal conditions during vibrational sounding and furthermore examines the role of vibrational sounding in multisensory orientation at different ambient temperatures.Die Schlupfwespe Pimpla turionellae parasitiert versteckte Lepidopterenpuppen und orientiert sie sich bei der Wirtssuche multisensorisch mittels visueller Reize und aktiver Vibrationsortung mit selbst produzierten Schwingungen (Vibrational-Sounding). Die Studie untersucht, inwieweit die Wespen bei Änderung der Umgebungstemperaturen von 8-26°C (1) zwischen der temperatur-sensitiven vibratorischen und der -insensitiven visuellen Orientierung wechseln und (2) gegebenenfalls selbst die Körpertemperatur regulieren können, um die sehr präzise Vibrationsortung bei niedrigen Temperaturen aufrechtzuerhalten. Messungen mit Infrarot-Thermographie zeigen, dass suchende Wespen leicht erhöhte Körpertemperaturen während der vibratorischen Wirtssuche aufweisen, welche auf metabolische Wärmeproduktion zurückzuführen sind. Wahlexperimente unter kontrollierten Temperaturen zeigen zudem, dass die Nutzung der temperatur-sensitiven vibratorischen Reize bei pessimalen Temperaturen abnimmt und die Wespen auf fast ausschließliche visuelle Orientierung wechseln. Folglich wird die Relevanz einzelner Reize bei der multisensorischen Orientierung direkt vom Faktor Temperatur beeinflusst. Solange ein zuverlässiger Reiz vorhanden ist, nimmt dabei auch die Präzision der Lokalisation insgesamt nicht ab

Robot Engraving Services in Industry

This chapter presents a software system created to allow to design complex robot trajectories in the cartesian space, used for tasks like milling or engraving with the aid of a robot. The experimental setup was created using an ABB (ASEA Brown Boveri) IRB 140 robot on which was mounted an engraving tool (which was equipped with a high frequency vibrating pin) or a drilling tool (an electric milling machine controlled with I/O signals) and a computer which is executing a CAD application allowing the design of the path that the robot must follow in order to execute the engraving/milling task. The robot job or task is defined by the set of surfaces of the raw object and of the object after being processed, by subtracting these two surfaces the robot task is given by the set of points resulted after the subtraction. The subtraction operation offers a set of points which must be connected in order to obtain the final trajectory, if the task is to engrave a shape then the tool will be normal to the object surface. The algorithm which is generating the surface is presented along with some experimental results

MENINGKATKAN KEMAMPUAN BERPIKIR KREATIF DAN KEMANDIRIAN BELAJAR SISWA SMA DENGAN MODEL PEMBELAJARAN CONTEXTUAL TEACHING AND LEARNING (CTL) PADA MATERI PELUANG

The ability to think creatively and learn independently of students is very important in learning mathematics. As a result, we require a learning model that can help students develop their creative thinking skills and independent learning, such as the Contextual Teaching and Learning (CTL) learning model. This study aims to determine whether the Contextual Teaching and Learning (CTL) model can improve students' creative thinking skills and independent learning. The method in this study is quantitative with the CTL model using the Class Action Research (CAR) method which was carried out in class XII IPS 1 SMA Pasundan 7 Bandung with 30 students. The technique used in data collection is quantitative data with a test instrument and qualitative data with a questionnaire instrument. The findings indicated that using the CTL learning model in mathematics can improve students' creative thinking skills and independence in class XII IPS 1 SMA Pasundan 7 Bandung. CTL model students outperform conventional learners in terms of creative thinking ability and mathematical learning independence. There is a link between students' mathematical learning independence and their ability to think creatively

How economic crisis is affecting firms? Building resilience capacity through innovation

More than ever firms will be required to develop strategies for coping with future shocks and stresses to our economic and social infrastructures. They will need to build the so called resilience capacity, which is an umbrella term for the planning and design strategies that help firms to develop the necessary capacity to meet challenges. The present paper, based on an assessment of works that explore recent European reports on innovation performance, discusses some underling effects of the economic crisis. This discussion reveals the main differentiating impacts of a major downturn on innovation behavior. Some of the conclusions acknowledge that firms will have to find new ways to reduce their risk-averse dependency and become more flexible. To become more resilient, firms will need to adopt planning and design strategies that allow them to develop the capacities to better respond and adapt to the emerging economic and social stresses. Developing these capacities will involve firms in a complex web of planning and development decisions that, in combination, must be designed to transform our current economic systems into much more flexible and dynamic ones. Small and medium enterprises are more exposed to high competitive pressures. Thus, they have to search for new business opportunities. The choice of sectors and the design of public procurement policies can provide new opportunities and it is very likely that those that manage to capture them will be the winners. With the polarization of innovation and knowledge creation across Europe, a few countries are responsible for the bulk of innovation and knowledge production. The technology gap provides a fundamental potentiality for lagging behind countries to catch-up. However, there is a general fragility as major effects of the crisis have shown. Therefore, a more articulated policy needs to be put in practice as suggested and more attention should be given to investment in knowledge diffusion and absorption depending on the specific national context. The fact that some structural characteristics of the national innovation system explain persistency of innovation in response to major exogenous shocks sheds some light on the behavior of firms during crisis. This represents a step forward in terms of understanding the mechanisms underlying the relationship between macro and micro-determinants of innovation

Quantum thermodynamics of the driven resonant level model

We present a consistent thermodynamic theory for the resonant level model in the wide band limit, whose level energy is driven slowly by an external force. The problem of defining 'system' and 'bath' in the strong coupling regime is circumvented by considering as the 'system' everything that is influenced by the externally driven level. The thermodynamic functions that are obtained to first order beyond the quasistatic limit fulfill the first and second law with a positive entropy production, successfully connect to the forces experienced by the external driving, and reproduce the correct weak coupling limit of stochastic thermodynamics.Comment: Final version as publishe

Effects of pre- and post-electrospinning plasma treatments on electrospun PCL nanofibers to improve cell interactions

In this study, liquid plasma treatment was used to improve the morphology of Poly-CaproLactone (PCL) NanoFibers (NFs), followed by performing a Dielectric Barrier Discharge (DBD) plasma surface modification to enhance the hydrophilicity of electrospun mats generated from plasma-modified PCL solutions. Cell interaction studies performed after 1 day and 7 days clearly revealed the highly increased cellular interactions on the double plasma-treated nanofibers compared to the pristine ones due to the combination of (1) a better NF morphology and (2) an increased surface hydrophilicity

Investigations of the role of colloids in radionuclide migration

The mobility of radionuclides through the Geosphere depends greatly on the sorption of radionuclides to the host rock. However, the presence of colloidal particles may influence the transport of radionuclides. Given a stable and mobile colloidal suspension which sorbs radionuclides onto its surface, the radionuclide may be transported along with the colloidal suspension. Given an irreversible interaction, radionuclides may be transported until the colloids flocculate. A reversible interaction, may lead to a scenario where the radionuclide is immobilised by sorption to the host rock. The work presented herein provides insight to the reversibility of the interaction of Cs+, Ni2+ and Eu3+ with two colloidal suspensions, boehmite and montmorillonite. The main difference between the colloidal phase and the solid phase of a mineral is the surface area to mass ratio, greater for the colloidal phase, as shown by the results herein. Assuming equal chemistry between colloidal and solid surface, sorption experiments have been carried out to relate the distribution ratio, Rd, for colloids and for solids with the ratios between surface areas. An attempt to develop a mathematical expression was made. The effect of humic acid on the sorption of metals onto colloidal boehmite was investigated. In all cases, the sorption of metals onto boehmite was hindered by the presence of humic acid. The linear additive model was tested on the experimental results. The transport of radionuclides associated to inorganic colloids has been assessed by means of column experiments. A radiometric technique consisting of radiolabelling inorganic silica colloids with 152Eu spike was used to detect and quantify the migration of silica colloids through a sand column. Furthermore,the same method was used to investigate the migration of 137Cs associated to silica colloids through a sand column. The mobility of the radionuclide was found to be enhanced by the silica colloids.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

The Application of Microwave Energy in Mineral Processing – a Review

This paper presents a review of the application of microwave energy in the field of mineral processing at the Institute of Geotechnics,Slovak Academy of Sciences. The influence of microwave radiation of rocks on the failure disintegration of minerals and ores as well as,a modification of magnetic properties and thermal processing of rocks was studied. Moreover, the rate of microwave heating of minerals,effect of microwaves on coal desulphurisation and the extraction of diterpanes from coal were investigated