The Neuropeptide Regulation of Host-Seeking Behavior in Aedes Aegypti Mosquitoes

Aedes aegypti mosquitoes are the principal vectors for several human diseases including Dengue Fever, which causes ~400 million cases and ~24,000 deaths per year (Bhatt et al., 2013; WHO, 2002). Novel strategies to combat mosquito-borne diseases are needed for A. aegypti and other mosquitoes such as the malaria vector Anopheles gambiae. Our goal was to discover new ways to interfere with the ability of a mosquito to locate a human host for a blood meal. Currently, the mechanistic basis of host-seeking and its regulation remain incompletely understood. Although it is known that mosquitoes require human odor cues to locate a human host, the critical odor components and associated olfactory receptors have not been identified (Klowden, 1995; Takken and Knols, 1999). Previous work showed that mosquito host-seeking behavior is inhibited by a hemolymph-borne humoral factor for three days following a blood meal. Subsequent studies identified Head Peptide-I as a candidate neuropeptide modulating this suppression in host-seeking behavior. This conclusion was strengthened by the observation that Head Peptide-I injection into non-blood-fed females triggered the inhibition of host-seeking. The mechanism by which this important peptide alters mosquito behavior and the receptor through which it signals are unknown (Brown et al., 1994). We used a cell-based calcium-imaging screen to identify the G-protein coupled receptor NPY-Like Receptor-1 (NPYLR1) as a candidate Head Peptide-I receptor. We found that multiple NPYLR1 agonists, including the feeding-related Short-Neuropeptide-3 (sNPF3), are capable of inhibiting host-seeking behavior when injected into non-blood-fed females. To investigate whether NPYLR1 is required for Head Peptide-I inhibition, we pioneered targeted mutagenesis with zinc-finger nucleases to create multiple NPYLR1 null-mutant mosquito lines. We predicted that these mutants would no longer show inhibition of host-seeking behavior after a blood meal. While we can say with certainty that NPYLR1 is a receptor for Head Peptide-I, we found no behavioral effects for NPYLR1 mutants in locomotion, egg-laying, sugar feeding, blood feeding, or host-seeking behavior. Our results suggest that NPYLR1 is not required in vivo for Head Peptide-I action and that a redundant signaling mechanism for behavioral inhibition exists. Future work will determine the necessity of Head Peptide-I during host-seeking inhibition and attempt to identify additional Head Peptide-I and sNPF receptors. This research will clarify the mechanism of Head Peptide-I inhibition and could form the basis for novel strategies to control mosquito host-seeking behavior

Disrupted meaning: a study of subverting logic through artists' books

This dissertation will discuss artists’ books as a form of visual arts practice that has been developed primarily since the 1960s. Works associated with this term can be distinguished from books in general and even books containing works of art, in that artists’ books are works of art in and of themselves. In particular, this dissertation will focus on non-narrative, nonlinear or disrupted artists’ books that require alternate or reinvented methods of reception and interpretation as they put forward different experiences to those of traditional books. In order to approach this focus from a theoretical perspective, which is currently lacking in existing literature on artists’ books, there are four key areas that will be examined, as they will provide the context for the examination of non-narrative artists’ books. The first is an account of artists’ books in general, where a brief history and various conceptual and material approaches related to their practice will be outlined. Secondly, modes of narrative communication conducted both through books and in society in general will be discussed. This is important for the dissertation because it will outline related book and narrative conventions that the particular works in question will be shown to depart from. The third field that will be considered concerns aesthetic debates. In order to situate non-narrative artists’ books in these debates, the presence of an illogical signifier or non-narrative occurrence in a visual work will be explored as a potential aesthetic element. The fourth field to be examined addresses the processes and effects related to non-narrative ordering in literary, film and visual works in general. Once the aforementioned areas have been addressed, specific nonlinear or disrupted artists’ books will be discussed. This discussion will be carried out in terms of content, structure, reader role and experience and alternate methods of comprehension that may be required, so that the various ways in which such works depart from traditional books can be considered and responded to. Through these considerations, this dissertation will identify the potential relevance and functions of non-narrative book works as a mode of contemporary art practice. The dissertation does not seek to examine overt structures of meaning, but to investigate disruptive or illogical spaces that arise within a work. This is the gap in existing literature that will be filled, thereby providing a theoretical basis for the viewing and discussion of non-narrative artists’ books

Acroneuria lycorias (Boreal Stonefly, Plecoptera: Perlidae) Emergence Behaviors Discovered in Pinus strobus Canopy

Species of Plecoptera, or stoneflies, are known to use vertical emergence supports, and researchers believe many species of Plecoptera exploit arboreal habitats during emergence. However, the exact nature of these arboreal behaviors has largely remained a mystery. While exploring the habitat potential of Pinus strobus (L.) (Eastern White Pine) canopies in northern Wisconsin we observed Acroneuria lycorias (Newman) (Boreal Stonefly, Plecoptera: Perlidae) exuviae at heights as high as 12m (observations at 6.6, 9, 9.5, and 12m). Most A. lycorias exuviae appeared to have a strong preference for emergence sites at the underside or base of branches similar to some Odonate species. We also observed A. lycorias, adults climbing upwards along the main stem, post-emergence, to heights up to 22m. To our knowledge, these heights represent the greatest heights ever documented for A. lycorias adults and exuviae, or any Plecopteran species. While other researchers have speculated that A. lycorias uses arboreal habitats during emergence, these behaviors were considered almost impossible to describe. Our observations provide us with new insights into Plecopteran emergence behaviors, especially for this species. We propose three alternative hypotheses that may explain these unique emergence behaviors

Quantification and possible causes of declining groundwater resources in the Euro-Mediterranean region from 2003 to 2020

Groundwater resources in Euro-Mediterranean countries provide a large part of the population’s water supply and are affected to varying degrees by anthropogenic use and climatic impacts. In many places, significant groundwater-level declines have already been observed, indicating an imbalance between natural groundwater recharge and groundwater abstraction. The extent of changes in groundwater storage (GWS) in the period 2003–2020 is quantified for the Euro-Mediterranean region using the latest data from the Gravity Recovery and Climate Experiment (GRACE/GRACE-FO) satellite mission and recently reanalyzed ERA5-Land climate data from the European Centre for Medium-Range Weather Forecasts. The results are set in relation to the prevailing climate, the regional hydrogeological setting, and annual groundwater recharge and abstractions on country level. Analysis of the mean annual trends over the study period shows significant decreases in GWS in many countries of Europe, Northern Africa and the entire Arabian Peninsula. Overall, there are significantly negative trends in about 70% of the study region. The mean of the trends across the Euro-Mediterranean region is –2.1 mm/year. The strongest negative trends in GWS per country are observed in Iraq and Syria (–8.8 and –6.0 mm/year, respectively), but also countries in central and eastern Europe are affected by depleting aquifers. The results are a clear indicator of the already medium-term groundwater stress in the Euro-Mediterranean region, which is expected to increase in the future, and demonstrate the need for adapted strategies for sustainable groundwater management on a transregional scale in the context of climate change and population growth

Framework for Inclusive Literature in Teacher Education

A broad selection of appropriately inclusive literature is a major step in creating a classroom that honors the diverse population of students and creates a welcoming, accepting atmosphere. Children who find stories reflecting their experience feel seen and valued. Diverse classroom literature also opens minds, extends knowledge, and increases compassion by allowing children to learn about their classmates’ cultures and experiences. The purpose of this article was to provide a framework for evaluating diverse texts for preservice teachers. We developed a framework with eight different categories of inclusive children’s literature based on established theories of culturally relevant pedagogy. It provides preservice teachers with a means to review children’s books to ensure that their use of literature is varied, sensitive, and reflective of diversity. We concluded that teacher-education programs must do more to meet these challenges

Up- and downshoot in adduction after monocular patching in normal volunteers

Upshoot-in-adduction and downshoot-in-adduction are non-paretic motility disorders that usually accompany a horizontal squint in children, together with V- or A-pattern motility. Upshoot-in-adduction may sometime mimic a superior oblique palsy. The authors have found that even in healthy volunteers these motility disorders can be found and made manifest by patching. One eye of complaint-free volunteers with full stereopsis was patched for three days. Then the eye movements of the patched eye were recorded with the search coil technique, first before taking the patch off and secondly after putting the patch on the other eye. The latter registration served as reference for the first registration. It was found that 11 out of 18 volunteers had developed an upshoot-in-adduction of the patched eye. In five cases no directional change was found whereas two cases had developed a downshoot-in-adduction. It seems that up- and downshoot-in-adduction are latent motility disorders that become manifest after disruption of fusion. In addition, the authors found undershooting saccades and postsaccadic drift of the patched eyes

Worldwide international trade and economic development with an emphasis on Australia

In this paper, we investigate the contribution international trade makes to growth in small population developed economies, with an emphasis on Australia, using complex network analysis. We also investigate the opportunities available so these economies to improve their position within the international trade network through membership of a trade integration bloc, and we discuss the role that firm-level actions play in the generation of the macro-level patterns of trade and development. Complementary case study data from Australian firms regarding their process of integration with the international trade network are drawn upon to elaborate these actions. The findings indicate that economic growth is primarily driven by the formation of new international trade connections. However, such connections are difficult for small firms to make, which poses potential problems for countries whose economies are dominated by small firms

The underdetermined knowledge-based theory of the MNC

This paper revisits two core propositions in the knowledge-based view of the firm propounded in the seminal work by Kogut and Zander (1993): (a) that MNCs exist because transfers and re-combinations of knowledge occur more efficiently inside MNCs than between MNCs and third parties, and (b) the threat of opportunism is not necessary (although it may be sufficient), to explain the existence of the MNC. We question these conclusions, arguing that firms are only one of many types of ‘epistemic communities’ possessing and nurturing procedural norms, identity, and the cognitive, linguistic and reflexive attributes conducive to efficient exchange and recombination of knowledge. Through their ability to attenuate opportunism, the existence of non-firm epistemic communities has interesting implications not only for the knowledge-based view but also for the applicability of transaction cost economics in the analysis of the scope of the firm

International business relationships triads: Classical-type and relational-type interactions between Chinese and western firms

China’s expanding position within the global business arena has placed focus on its role in assisting to stimulate the global economy during the current ‘global financial crisis’. This raises the importance of better understanding how the Chinese conduct their inter-firm interactions, in their exchanges between Chinese and Western firms. We report an expository study that identifies both classical-type exchange and interactions that are relational-type in the one context and how these conflate to form triadic structures within business networks. From case study evidence, we propose a typology of triadic interorganisational forms. To understand better exchange in this complex international marketing context, and the additional demands this places on relationships management, it is important that we understand the causes and nature of the fuzziness of these opaque inter-firm network structures

Influence of sediments burying the discharge area of a karst aquifer on the groundwater flow field—Numerical testing of conceptual models

Karst springs are a natural result of karst water discharging to the surface through unimpeded pathways where the water table meets the surface. This study investigates the impact of alluvial deposits of varying thicknesses and permeabilities burying the main outlet (karst spring) of a well-developed conduit network on karst drainage, including the development of hydraulic heads, drainage patterns and conduit-matrix interactions in response to a positive base-level shift. Numerical testing using FEFLOW on a simplified conceptual model of a hypothetical karst aquifer with six different model configurations was used to examine various drainage structures (with and without flow through a conduit), spring conditions (free vs. partially/fully clogged), sediment cover thickness (20 and 50 m), and hydraulic conductivity of the sediments (low and high). The numerical testing model incorporated one-dimensional discrete feature elements to simulate conduit flow and coupled conduit-matrix interactions. Results indicate that even with a fully plugged outlet, the conduit network remains a significant contributor to the drainage system, collecting water from the matrix in the recharge zone. As the outlet becomes buried, the hydraulic head increases along the conduit, forcing water back up into the matrix. The elevated hydraulic head in the karst system will cause new conduits to form at the contact between limestone and sediments, creating new potential spring sites (or reactivating existing paleo-phreatic levels). Artesian conditions will occur below the low permeability sediments. These findings provide valuable insights into the responses of natural karst systems