Defining the concept of ‘tick repellency’ in veterinary medicine

Although widely used, the term repellency needs to be employed with care when applied to ticks and other periodic or permanent ectoparasites. Repellency has classically been used to describe the effects of a substance that causes a flying arthropod to make oriented movements away from its source. However, for crawling arthropods such as ticks, the term commonly subsumes a range of effects that include arthropod irritation and consequent avoiding or leaving the host, failing to attach, to bite, or to feed. The objective of the present article is to highlight the need for clarity, to propose consensus descriptions and methods for the evaluation of various effects on ticks caused by chemical substances

Infrared Ellipsometry Analysis of Heritage Photographic Prints

[EN] Focusing on the photographic archive of Julian Carrillo (Mexico), we study and characterize the photographic processes of a set of 13 photographs dated between 1884 and 1925. By using infrared spectroscopic ellipsometry, we classified a selected set of photographs according to its kind of binder. Thus, we recognized for each photograph, the presence of proteins, and therefore, the particular photographic process. Furthermore, we have identified the presence of baryta layer, the use of plasticizer, and the eventual coating utilized to protect the photograph, whose composition was based in natural organic components, mainly shellac, beeswax, or camphorNieto-Villena, A.; Martinez, JR.; Flores-Camacho, JM.; Lastras-Martinez, A.; De La Cruz-Mendoza, JA.; Ortega-Zarzosa, G.; Valcarcel Andrés, JC.... (2018). Infrared Ellipsometry Analysis of Heritage Photographic Prints. Studies in Conservation. 63(8):466-476. https://doi.org/10.1080/00393630.2018.1476962S466476638Brambilla, L., Riedo, C., Baraldi, C., Nevin, A., Gamberini, M. C., D’Andrea, C., … Toniolo, L. (2011). Characterization of fresh and aged natural ingredients used in historical ointments by molecular spectroscopic techniques: IR, Raman and fluorescence. Analytical and Bioanalytical Chemistry, 401(6), 1827-1837. doi:10.1007/s00216-011-5168-zCasoli, A., & Fornaciari, S. (2014). An analytical study on an early twentieth-century Italian photographs collection by means of microscopic and spectroscopic techniques. Microchemical Journal, 116, 24-30. doi:10.1016/j.microc.2014.04.003Cattaneo, B., Chelazzi, D., Giorgi, R., Serena, T., Merlo, C., & Baglioni, P. (2008). Physico-chemical characterization and conservation issues of photographs dated between 1890 and 1910. Journal of Cultural Heritage, 9(3), 277-284. doi:10.1016/j.culher.2008.01.004Daher, C., Paris, C., Le Hô, A.-S., Bellot-Gurlet, L., & Échard, J.-P. (2010). A joint use of Raman and infrared spectroscopies for the identification of natural organic media used in ancient varnishes. Journal of Raman Spectroscopy, 41(11), 1494-1499. doi:10.1002/jrs.2693Edwards, H. G. M., Farwell, D. W., & Daffner, L. (1996). Fourier-transform Raman spectroscopic study of natural waxes and resins. I. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 52(12), 1639-1648. doi:10.1016/0584-8539(96)01730-8Fujiwara, H. (2007). Spectroscopic Ellipsometry. doi:10.1002/9780470060193Hendriks, K., & Ross, L. (1988). Chemical Treatments of Discoloured Photographic Prints: Image Manipulation or Legitimate Restoration? The Journal of Photographic Science, 36(3), 132-132. doi:10.1080/00223638.1988.11736990Mallégol, J., Gardette, J.-L., & Lemaire, J. (2000). Long-term behavior of oil-based varnishes and paints. Photo- and thermooxidation of cured linseed oil. Journal of the American Oil Chemists’ Society, 77(3), 257-263. doi:10.1007/s11746-000-0042-4Nieto-Villena, A., Martínez, J. R., de la Cruz-Mendoza, J. A., Valcárcel-Andrés, J. C., Ortega-Zarzosa, G., Solbes-García, Á., & Vázquez-Martínez, E. (2018). Atomic force microscopy as a tool for binder identification in ancient photographic processes. Surface and Interface Analysis, 50(4), 496-505. doi:10.1002/sia.6408Ostroff, Eugene. 1966. “Restoration of Photographs by Neutron Activation.” Science 154 (3745): 119–123. http://science.sciencemag.org/content/154/3745/119.Othmer, Kirk, ed. 2005. Encyclopedia of Chemical Technology. Vol. 17, 5th ed. New York: Wiley.Ricci, C., Bloxham, S., & Kazarian, S. G. (2007). ATR-FTIR imaging of albumen photographic prints. Journal of Cultural Heritage, 8(4), 387-395. doi:10.1016/j.culher.2007.07.002Sifontes, Á. B., Cañizales, E., Toro-Mendoza, J., Ávila, E., Hernández, P., Delgado, B. A., … Cruz-Barrios, E. (2015). Obtaining Highly Crystalline Barium Sulphate Nanoparticles via Chemical Precipitation and Quenching in Absence of Polymer Stabilizers. Journal of Nanomaterials, 2015, 1-8. doi:10.1155/2015/510376Stulik, Dusan, Herant Khanjian, Alberto de Tagle, and Alexandra M. Botelho. 2002. “Investigation of Jean-Louis-Marie-Eugene Durieu’s Toning and Varnishing Experiments: A Non-Destructive Approach.” ICOM Committee for Conservation 13th Triennial Meeting, Río de Janeiro, 658–663.Price, Beth A., and Boris Pretzel, eds. 2009. Infrared and Raman Users Group Spectral Database. 2007 ed. Vol. 1 & 2. Philadelphia: IRUG. Accessed June 20, 2014. http://www.irug.org/.Vila, A., & Centeno, S. A. (2013). FTIR, Raman and XRF identification of the image materials in turn of the 20th century pigment-based photographs. Microchemical Journal, 106, 255-262. doi:10.1016/j.microc.2012.07.01

Kontextmerkmale und die Bearbeitung von Aufgaben in einem Test naturwissenschaftlicher Kompetenz in der Grundschule

Im Rahmen der Forschung zu Schülervorstellungen konnten verschiedene Studien eine Abhängigkeit der geäußerten Vorstellungen vom jeweiligen Kontext belegen. Diese Erkenntnisse können zur Formulierung valider Modelle naturwissenschaftlicher Kompetenz in der Grundschule genutzt werden. Die Arbeit geht daher der Frage nach, ob kontextuelle Merkmale von schriftlichen, geschlossenen Aufgaben zur Erfassung der Kompetenz in den Themenbereichen Schwimmen/Sinken und Verdunstung/Kondensation das Antwortverhalten von Grundschulkindern beeinflussen. Die Analyse der Daten einer querschnittlichen (N=1820) und einer experimentellen (N= 308) Studie zeigte, dass differentiell nach Themenbereich entweder ein Kontextmerkmal (in den Bereichen Dichte und Verdrängung im Themenbereich Schwimmen/Sinken) oder der konkrete Inhalt der vorgegebenen Antwortalternativen (im Themenbereich Verdunstung/Kondensation) der erklärungsmächtigste Faktor war

A study on the long-term efficacy of Seresto® collars in preventing Babesia canis (Piana & Galli-Valerio, 1895) transmission to dogs by infected Dermacentor reticulatus (Fabricius, 1794) ticks

Abstract Background An imidacloprid/flumethrin collar (Seresto®) was previously shown to prevent infection with Babesia canis, transmitted by Dermacentor reticulatus, in dogs for up to 1 month after application. The present study evaluated the prevention of transmission throughout the claimed efficacy period of 8 months. Methods Eight animals each were randomly included in groups 1 (negative control) and 2 (Seresto® collar), respectively. Animals in group 2 received the Seresto® collar on Day 0. Tick challenges were performed monthly from the 2nd to the 8th month. Assessment criteria included in situ tick counts 48 hours post-challenge, polymerase chain reaction (PCR) analyses and immunofluorescence assays (IFA). Whenever dogs were diagnosed with babesiosis they were “rescue-treated”, excluded and replaced. Consequently, 24 replacement animals were introduced at various time points throughout the study in the control group; thus data for a total of 32 dogs were available in the latter group at study termination. Results Acaricidal efficacy for in situ counts was 93% on Day 30, and ranged from 97 to 100% thereafter. No B. canis specific DNA or antibodies were detected in any Seresto®-treated dog at any time. Babesia canis-specific DNA and antibodies were detected in 2–6 of 8 control dogs after each challenge, confirming the validity of the challenge model. Conclusions The Seresto® collar was highly effective against challenges with D. reticulatus ticks for up to 8 months. The high sustained acaricidal efficacy over this period prevented transmission of B. canis, thus fully protecting dogs against infection in this experimental infestation model

Transmission of Anaplasma phagocytophilum (Foggie, 1949) by Ixodes ricinus (Linnaeus, 1758) ticks feeding on dogs and artificial membranes

Abstract Background The interplay of speed of activity of acaricidal products and tick-borne pathogen transmission time is the major driver for disease prevention. This study aimed to investigate the time required for transmission of Anaplasma phagocytophilum by adult Ixodes ricinus ticks in vivo on dogs, and to confirm the time required for transmission observed in vivo, in vitro. Methods Nymphs of I. ricinus were experimentally infected with an A. phagocytophilum strain of canine origin. Dogs were allocated to 6 groups of 3 dogs each. Groups 1–5 were infested with 50 A. phagocytophilum-infected female adult ticks on Day 0. Ticks were removed post-infestation at 3, 6, 12, 24 and 48 h. Dogs in Group 6 were infested with 60 A. phagocytophilum-infected female adult ticks (left on dogs until engorged). Dogs were observed daily for general health and clinically examined on Day 0, and weekly from Day 14. Blood was collected for qPCR and serological analysis on Day 0 (pre-challenge) and weekly thereafter. In the in vitro study each artificial feeding chamber was seeded with 10 adult ticks (5 male/5 female), attachment assessed, and blood pools sampled for qPCR at 6 h intervals up to 72 h after first tick attachment. Results Anaplasma phagocytophilum specific antibodies and DNA were detected in all 3 dogs in Group 6. No A. phagocytophilum-specific antibodies or DNA were detected in any dogs in Groups 1–5. All dogs remained healthy. Female tick attachment in 60 artificial feeding chambers over 72 h ranged between 20–60%. Anaplasma phagocytophilum DNA was detected in the blood collected from 5% of chambers sampled at 6 h, with the highest number of positive samples (16.3%) observed at 36 h. Conclusions Transmission of A. phagocytophilum by I. ricinus ticks starts within a few hours after attachment but establishment of infections in dogs is apparently dependent on a minimum inoculation dose that was only observed when ticks attached for greater than 48 h. These findings highlight the need for acaricidal products to exert a repellent and/or rapid killing effect on ticks to forestall transmission and subsequent disease

Disrupted function of lactate transporter MCT1, but not MCT4, in Schwann cells affects the maintenance of motor end-plate innervation.

Recent studies in neuron-glial metabolic coupling have shown that, in the CNS, astrocytes and oligodendrocytes support neurons with energy-rich lactate/pyruvate via monocarboxylate transporters (MCTs). The presence of such transporters in the PNS, in both Schwann cells and neurons, has prompted us to question if a similar interaction may be present. Here we describe the generation and characterization of conditional knockout mouse models where MCT1 or MCT4 is specifically deleted in Schwann cells (named MCT1 and MCT4 cKO). We show that MCT1 cKO and MCT4 cKO mice develop normally and that myelin in the PNS is preserved. However, MCT1 expressed by Schwann cells is necessary for long-term maintenance of motor end-plate integrity as revealed by disrupted neuromuscular innervation in mutant mice, while MCT4 appears largely dispensable for the support of motor neurons. Concomitant to detected structural alterations, lumbar motor neurons from MCT1 cKO mice show transcriptional changes affecting cytoskeletal components, transcriptional regulators, and mitochondria related transcripts, among others. Together, our data indicate that MCT1 plays a role in Schwann cell-mediated maintenance of motor end-plate innervation thus providing further insight into the emerging picture of the biology of the axon-glia metabolic crosstalk