Las láminas zootómicas del profesor Paul Pfurtscheller de Viena: un material científico renovador en las aulas españolas en el primer tercio de siglo XX / [The zootomic slides of Professor Paul Pfurtscheller from Vienna: innovative scientific material in Spanish classrooms in the first third of the 20th century]

Paul Pfurtscheller fue uno de los creadores de material didáctico más universales y re-conocidos dentro de la enseñanza de la Historia Natural, sus láminas de pared de zoología tuvieron presencia a nivel internacional en escuelas normales, institutos de segunda enseñanza e incluso en gabinetes y laboratorios universitarios. Doctor por la Universidad de Viena con una tesis de Botá-nica desarrolló una carrera prominente como profesor de secundaria de la asignatura de Historia Natural en el Gymnasium (Instituto) Franz Josef de Viena, desarrollando un gabinete museo para su asignatura y creando 39 láminas zootómicas como apoyo a su docencia personal. La edición de sus láminas a través de prestigiosa casa editorial vienesa A. Pichlers Witwe & Sohn y posteriormente por la holandesa Martinus Nijhoff permitió la difusión de su trabajo a través de Europa y América. Tras una aproximación biográfica del personaje basada en los documentos encontrados en la Biblioteca Nacional de Austria y en los de la Universidad de Viena, se ha indagado en su papel como docente y en la génesis de su colección, en su éxito pedagógico y el papel que tuvieron en las aulas espa-ñolas de principios de siglo XX. Dentro de las fuentes a considerar destacan las propias láminas, los catálogos comerciales, las leyendas explicativas, los manuales de clase, memorias anuales de los centros estudiados y las imágenes de las aulas, no como meras ilustraciones, sino como objeto de estudio para analizar el espacio escolar y el papel didáctico de las láminas. (AU)

An automated aquatic rack system for rearing marine invertebrates.

BACKGROUND: One hundred years ago, marine organisms were the dominant systems for the study of developmental biology. The challenges in rearing these organisms outside of a marine setting ultimately contributed to a shift towards work on a smaller number of so-called model systems. Those animals are typically non-marine organisms with advantages afforded by short life cycles, high fecundity, and relative ease in laboratory culture. However, a full understanding of biodiversity, evolution, and anthropogenic effects on biological systems requires a broader survey of development in the animal kingdom. To this day, marine organisms remain relatively understudied, particularly the members of the Lophotrochozoa (Spiralia), which include well over one third of the metazoan phyla (such as the annelids, mollusks, flatworms) and exhibit a tremendous diversity of body plans and developmental modes. To facilitate studies of this group, we have previously described the development and culture of one lophotrochozoan representative, the slipper snail Crepidula atrasolea, which is easy to rear in recirculating marine aquaria. Lab-based culture and rearing of larger populations of animals remain a general challenge for many marine organisms, particularly for inland laboratories. RESULTS: Here, we describe the development of an automated marine aquatic rack system for the high-density culture of marine species, which is particularly well suited for rearing filter-feeding animals. Based on existing freshwater recirculating aquatic rack systems, our system is specific to the needs of marine organisms and incorporates robust filtration measures to eliminate wastes, reducing the need for regular water changes. In addition, this system incorporates sensors and associated equipment for automated assessment and adjustment of water quality. An automated feeding system permits precise delivery of liquid food (e.g., phytoplankton) throughout the day, mimicking real-life feeding conditions that contribute to increased growth rates and fecundity. CONCLUSION: This automated system makes laboratory culture of marine animals feasible for both large and small research groups, significantly reducing the time, labor, and overall costs needed to rear these organisms.

Augmenting biologging with supervised machine learning to study in situ behavior of the medusa Chrysaora fuscescens.

Zooplankton play critical roles in marine ecosystems, yet their fine-scale behavior remains poorly understood because of the difficulty in studying individuals in situ Here, we combine biologging with supervised machine learning (ML) to propose a pipeline for studying in situ behavior of larger zooplankton such as jellyfish. We deployed the ITAG, a biologging package with high-resolution motion sensors designed for soft-bodied invertebrates, on eight Chrysaora fuscescens in Monterey Bay, using the tether method for retrieval. By analyzing simultaneous video footage of the tagged jellyfish, we developed ML methods to: (1) identify periods of tag data corrupted by the tether method, which may have compromised prior research findings, and (2) classify jellyfish behaviors. Our tools yield characterizations of fine-scale jellyfish activity and orientation over long durations, and we conclude that it is essential to develop behavioral classifiers on in situ rather than laboratory data.

Development of a vortex generator to perturb fish locomotion.

Knowledge about the stiffness of fish fins, and whether stiffness is modulated during swimming, is important for understanding the mechanics of a fin's force production. However, the mechanical properties of fins have not been studied during natural swimming, in part because of a lack of instrumentation. To remedy this, a vortex generator was developed that produces traveling vortices of adjustable strength which can be used to perturb the fins of swimming fish. Experiments were conducted to understand how the generator's settings affected the resulting vortex rings. A variety of vortices (14-32 mm diameter traveling at 371-2155 mm s-1) were produced that elicited adequate responses from the fish fins to help us to understand the fin's mechanical properties at various swimming speeds (0-350 mm s-1).

A novel technique for the precise measurement of CO2 production rate in small aquatic organisms as validated on aeshnid dragonfly nymphs.

The present study describes and validates a novel yet simple system for simultaneous in vivo measurements of rates of aquatic CO2 production (MCO2 ) and oxygen consumption (MO2 ), thus allowing the calculation of respiratory exchange ratios (RER). Diffusion of CO2 from the aquatic phase into a gas phase, across a hollow fibre membrane, enabled aquatic MCO2  measurements with a high-precision infrared gas CO2 analyser. MO2  was measured with a PO2  optode using a stop-flow approach. Injections of known amounts of CO2 into the apparatus yielded accurate and highly reproducible measurements of CO2 content (R2=0.997, P<0.001). The viability of in vivo measurements was demonstrated on aquatic dragonfly nymphs (Aeshnidae; wet mass 2.17 mg-1.46 g, n=15) and the apparatus produced precise MCO2  (R2=0.967, P<0.001) and MO2  (R2=0.957, P<0.001) measurements; average RER was 0.73±0.06. The described system is scalable, offering great potential for the study of a wide range of aquatic species, including fish.

Use of plastic tips in artificial feeding of Dermacentor (Anocentor) nitens females Neumann, 1897 (Acari: Ixodidae).

The establishment of laboratory colonies of ticks is often hampered by their lack of adaptation to alternative hosts. The aim of this study was to artificially feed partially engorged Dermacentor (Anocentor) nitens females through plastic tips, and to identify what are the optimal conditions of application of this technique to get as much as possible close to the natural conditions. The technique of artificial feeding through plastic tips allowed the engorgement of D. nitens ticks to a final weight within the normal range for the species.

An LED-based UV-B irradiation system for tiny organisms: System description and demonstration experiment to determine the hatchability of eggs from four Tetranychus spider mite species from Okinawa.

We developed a computer-based system for controlling the photoperiod and irradiance of UV-B and white light from a 5×5 light-emitting diode (LED) matrix (100×100mm). In this system, the LED matrix was installed in each of four irradiation boxes and controlled by pulse-width modulators so that each box can independently emit UV-B and white light at irradiances of up to 1.5 and 4.0Wm(-2), respectively, or a combination of both light types. We used this system to examine the hatchabilities of the eggs of four Tetranychus spider mite species (T. urticae, T. kanzawai, T. piercei and T. okinawanus) collected from Okinawa Island under UV-B irradiation alone or simultaneous irradiation with white light for 12hd(-1) at 25°C. Although no eggs of any species hatched under the UV-B irradiation, even when the irradiance was as low as 0.02Wm(-2), the hatchabilities increased to >90% under simultaneous irradiation with 4.0Wm(-2) white light. At 0.06Wm(-2) UV-B, T. okinawanus eggs hatched (15% hatchability) under simultaneous irradiation with white light, whereas other species showed hatchabilities <1%. These results suggest that photolyases activated by white light may reduce UV-B-induced DNA damage in spider mite eggs and that the greater UV-B tolerance of T. okinawanus may explain its dominance on plants in seashore environments, which have a higher risk of exposure to reflected UV-B even on the undersurface of leaves. Our system will be useful for further examination of photophysiological responses of tiny organisms because of its ability to precisely control radiation conditions.

Computer animation as a tool to study preferences in the cichlid Pelvicachromis taeniatus.

Four choice experiments were conducted with both sexes of the cichlid Pelvicachromis taeniatus using computer-manipulated stimuli of digital images differing in movement, body shape or colouration. The results show that computer animations can be useful and flexible tools in studying preferences of a cichlid with complex and variable preferences for different visual cues.

Olfactory responses of medically and economically important mites (Acari: Epidermoptidae and Acaridae) to volatile chemicals.

Dermatophagoides farinae Hughes (Acari: Epidermoptidae), the American house dust mite, and Tyrophagus putrescentiae (Schrank) (Acari: Acaridae), the mold mite, are medically and economically important but controlling them has proved difficult, and recolonization is commonplace. Their behavioral responses to different sources of volatile chemicals are still not fully elucidated. For the first time, the Y-tube olfactometer, which is an enclosed bioassay to resolve responses to test and control volatiles, has been successfully used with these mites. Mites were tested individually, and both T. putrescentiae and D. farinae responded to food volatiles. Y-tube olfactometers may be used to test for potential semiochemicals, thereby increasing knowledge of our behavior of astigmatic mites.

A polyethylenetherephthalate (PET) device for sampling freshwater benthic macroinvertebrates.

A new device to sample freshwater benthic macroinvertebrates was used in a low and sandy stretch of a Brazilian sub-tropical river (the River Cai, Triunfo, RS) and in one of its small tributaries, Bom Jardim brook (Arroio Bom Jardim). In this study, the effectiveness of this device, a PET sampler, was tested at different sites in the river and the brook throughout the four seasons between 2001-2002. Comparisons were made by PCA and ANOVA, both employing a bootstrap procedure based on similarity matrices. The PET sampler proved to be a reliable tool for detection of seasonal and spatial differences in richness, total abundance of organisms, and Shannon's diversity index in both river and brook and is therefore recommended for use in the monitoring of macroinvertebrate communities in this system.

Mesh size and bird capture rates in Mato Grosso do Sul State, Brazil.

Mist-nets alternating 36-mm and 61-mm mesh in woods and low vegetation of "cerrado" (Brazilian savanna) tested bird-capture efficiency relative to bird length and mass. Of 1,296 birds captured and 102 species, 785 (93 species) were with 36-m mesh and 511 (69 species) with 61-mm mesh. The 61-mm mesh improved capture rates only for some larger species; so, in general, 36-mm mesh mist-nets are more appropriate for field work in "cerrado" areas.