Miracle-dz/UniFAR-FTUs huggingface dataset:
Host-plant dependent wing phenotypic variation in the neotropical butterfly Heliconius erato

Most phytophagous insects feed on a single plant during development, and this may influence not only performance-linked traits, but also more subtle morphological differences. Insect-plant interactions are thus valuable for studying environmental influences on phenotypes. By using geometric morphometrics, we investigated the variation in forewing size and shape in the butterfly Heliconius erato phyllis reared on six species of passion vines (Passiflora spp.). We detected wing shape sexual dimorphism, for which the adaptive significance deserves further investigation. There was size as well as wing shape variation among individuals fed on different hosts. These subtle differences in shape were interpreted as environmental effects on development, which should be under weak natural selection for these traits, and therefore not strongly canalized. This result reinforces the role of plasticity on host-plant use, as well as the corresponding consequences on developmental variability among phytophagous insects. We propose that this variation can be an important factor in resource specialization and partner recognition, possibly triggering reproductive isolation and sympatric speciation in phytophagous insects. This interaction also shows itself as a good model for studying the role of environmental and interaction diversity in evolution.
PHYLOGENY OF THE NEMERTEAN SUBCLASS PALAEONEMERTEA (ANOPLA, NEMERTEA)

Abstract— A cladistic analysis based on 50 morphological characters was performed for 49 of the 98 species currently assigned to the subclass Palaeonemertea (phylum Nemertea), and six additional undescribed species. Thirty‐five species were excluded from the parsimony analysis because of the high number of unknowns in the character matrix, and one species since it was considered a nomen nudum. An initial analysis suggested that the subclass Hoplonemertea is the sistergroup to the clade Palaeo‐ and Heteronemertea and the ingroup cladograms are rooted using a paraphyletic outgroup based on this information. Seventy‐two equally most parsimonious cladograms were found; the consistency index was low but tree‐length distribution for the character set is skewed to the left, and the cladograms are invariably shorter than trees based on random data. These cladograms suggested a character transformation series for the cerebral organ where this complex character reappeared several times after being absent. We considered this biologically implausible and the final discussion is based on three cladograms, one step longer than the most parsimonious, where the evolution of this character appears to be more realistic. The cladistic analysis indicates that many previously recognized genera (e.g. Cephalothrix, Procephalothrix and Cephalotrichella), and higher taxa, are paraphyletic. It furthermore indicates that the previously suggested hypothesis of the Archinemertea as a monophyletic sistertaxon to Palaeonemertea is unsupported.
Production of Chitosan by fungi

Abstract Chitosan is a novel biopolymer with numerous industrial, food, and biomedical applications. Our studies examined the production of chitosan from mycelia of Absidia coerulea, Mucor rouxii, Gongronella butieri, Phvcomyces blakesleeanus and Absidia blakesleeana. In batch culture, strains were screened to determine the fastest growing and greatest chitosan‐yielding fungi. Optimum chitosan yields were observed for most cultures at 21°and 26°C in 1% yeast extract, 0.4% glucose, and 0.3% peptone. A. coerulea ATCC 14076 and NRRL 1315 were the best producers of chitosan of the strains examined. Chitosan yields of A. coerulea, M. rouxii, G. butieri, P. blakesleeanus and A. blakesleeana were 47–50, 29–32, 21–25, 6 and 7 mg/100 mL of medium, respectively. The degree of acetylation of chitosan ranged from 6 to 15%; the lowest was from strains of A. coerulea. Viscosity average molecular weights of fungal chitosans were equivalent, approximately 4.5 x 10s daltons. A. coerulea 14076 yielded the most chitosan, 51.
Nursery rearing of the Asian catfish, Clarias macrocephalus (Günther), at different stocking densities in cages suspended in tanks and ponds

Growth and survival of hatchery-bred Asian catfish, Clarias macrocephalus (Gunther), fry reared at different stocking densities in net cages suspended in tanks and ponds were measured. The stocking densities used were 285, 571 and 1143 fry m−3 in tanks and 114, 228 and 457 fry m−3 in ponds. Fish were fed a formulated diet throughout the 28-day rearing period. Generally, fish reared in cages in ponds grew faster, with a specific growth rate (SGR) range of 10.3–14.6% day−1, than those in cages suspended in tanks (SGR range 9–11.3% day−1). This could be attributed to the presence of natural zooplankton (copepods and cladocerans) in the pond throughout the culture period, which served as additional food sources for catfish juveniles. In both scenarios, the fish reared at lower densities had significantly higher SGR than fish reared at higher densities. In the pond, the SGR of fish held at 228 and 457 m−3 were similar to each other but were significantly lower than those of fish held at 114 m−3. The zooplankton in ponds consisted mostly of copepods and cladocerans, in contrast to tanks, in which rotifers were more predominant. Per cent survival ranged from 85% to 89% in tanks and from 78% to 87% in ponds and did not differ significantly among stocking densities and between rearing systems. In conclusion, catfish nursery in cages suspended in tanks and ponds is density dependent. Catfish fry reared at 285 m−3 in tanks and at 114 m−3 in ponds had significantly faster growth rates than fish reared at higher densities. However, the desired fingerling size of 3–4 cm total length for stocking in grow-out culture can still be attained at stocking densities of 457 m−3 in nursery pond and 571 m−3 in tanks.
Winter Social Organisation of Marsh Tits Poecile palustris in Britain

Abstract. We investigated the winter social organisation of a population of British Marsh Tits, using radio-tracking, colour-ringing, and analysis of spatial and social relationships. The observed social structure was defined by adults and juveniles occupying individual but partially-overlapping home-ranges, with typical groups of 2–3 birds (maximum of 9 birds) having a changeable composition. There was no evidence of exclusive territoriality among individuals or groups during the winter, and no evidence of stable social groups with a consistent membership. Instead, the major social units detected were male-female pairs, with mostly casual associations between other individuals. Individual home-ranges averaged 31 ha (10-63 ha, n = 9) and their core areas overlapped with each other by an average 14% (0-65%), indicating that Marsh Tits in this population had very large spatial habitat requirements during winter. Our results have relevance for Marsh Tit conservation, and also the understanding of the drivers and plasticity of social organisation in the family Paridae; we discuss our findings in the context of the discrete and basic flock system exhibited by other species within this group.
Major difference in mercury concentrations of the African big barb, Barbus intermedius (R.) due to shifts in trophic position

– The African big barb (Barbus intermedius, R.) from Lake Awassa, Ethiopia is an important fish species, especially with the ongoing decline of the Nile tilapia (Oreochromis niloticus, L.) fishery. Their diet and habitat use was studied using stomach content analyses, stable nitrogen and carbon isotopes, and transect netting. Mercury biomagnification was also determined. The big barb was found to primarily exist in the littoral habitat, with molluscs being their predominant food item. The proportion of small fish (Barbus paludinosus, P.) in the big barb diet tended to vary somewhat with size, with the largest fish tending to have the most piscivorous diet. Mercury concentrations in the big barb ranged from 0.01 to 0.94 mg·kg−1, and were positively related with size. Fish transects and stable isotope analyses suggest that there may be two feeding forms of big barb in Lake Awassa, with some larger fish preying upon fish (and accumulating higher mercury concentrations). With the declining Nile tilapia fishery in Lake Awassa, the implication of fishermen focusing on large big barb, with its associated higher Hg burdens, is significant with human health ramifications.
Barrier zone formation in host and nonhost trees inoculated with Ophiostoma ulmi. II. Ultrastructure

Barrier zone formation was studied in annual shoots and small branches of Ulmus americana L. , Prunus pensylvanica L.f. , and Populus balsamifera L. following inoculation with Ophiostoma ulmi (Buism.) Nannf. Ultrastructural observations showed that electron-opaque compounds, which usually were identified as containing phenolics by previous histochemical tests, were often present within cells of this tissue. Many lipidic globules were also observed within some barrier zone cells of Populus balsamifera. Additional wall layers, suberized or not, were frequently observed in these barrier zone cells. When histochemical tests for suberin at the light microscope level were strongly positive, the lamellation typical of suberin was evident in transmission electron microscopy. Gum canal formation in Prunus pensylvanica was found to be initiated and the canals widened predominantly by a lysogenous process. Key words: Dutch elm disease, nonhost plants, Ophiostoma ulmi, Ulmus americana, ultrastructure, gum canals, suber.
Cytotoxicity and phytochemical analyses of Orthosiphon stamineus leaves and flower extracts

Orthosiphon stamineus Benth (Lamiaceae) is a plant with many ethnobotanical uses including antifungal and antibacterial activities. This study is aimed to determine the cytotoxicity and phytochemical content of O. stamineus leaves and flower using ethanol and water as solvents. The cytotoxicity of the extracts towards Vero cell was determined by MTT assay. The CC50 values were between 3.4-7.4 mg/ml and can be considered as nontoxic. Phytochemical screening revealed terpenes, alkaloid and phenolic were present in the leaves and flower of O. stamineus that might pose as the bioactive compound.
Crosslinking studies on the conventional kinesin of Neurospora crassa

München vorgelegt von Katrin Hahlen aus Köln 2004 Ehrenwörtliche Versicherung Diese Dissertation wurde selbständig und ohne unerlaubte Hilfsmittel angefertigt. "Testing kinesin's flexibility by crosslinking: Which domains need to be mobile to allow mobility? " "Testing kinesin's flexibility by crosslinking: Which domains need to be mobile to allow mobility? " "The role of the neck in fast kinesins" "Crosslinking kinesin's neck-linker to the motor core" Workshop Molecular Motors and New Microscopic Techniques The work presented here was carried out in the laboratory of Prof.
Response of a perennial grassland to nitrogen and phosphorus additions in sub-tropical, semi-arid Australia

Soils of arid and semi-arid Australia are typically low in both N and P relative to arid zones elsewhere. We examined relative limitations of N and P on productivity of two native perennial grasslands of sub-tropical, semi-arid, north-west Australia. Effects of single and combined additions of N (50 kg ha−1) and P (25 kg ha−1) on growth and plant nutrients were documented over 2 years. Addition of N alone significantly increased total cover, above-ground biomass, N concentrations and N content, in the first year following above-average summer rains. These effects persisted into the second growing season but were of reduced magnitude. Addition of P alone increased P concentrations and aboveground P content but had negligible effects on biomass, indicating luxury consumption. Combined addition of N and P had similar effects to addition of N alone, strengthening the argument that N and not P was limiting to growth. Nitrogen limitation was clearly indicated by low N to P ratios (<7) in aboveground plant components.
ENVIRONMENTAL EFFECTS ON EXOPOLYMER PRODUCTION BY MARINE BENTHIC DIATOMS: DYNAMICS, CHANGES IN COMPOSITION, AND PATHWAYS OF PRODUCTION 1

Marine benthic diatoms excrete large quantities of extracellular polymeric substances (EPS), both as a function of their motility system and as a response to environmental conditions. Diatom EPS consists predominantly of carbohydrate‐rich polymers and is important in the ecology of cells living on marine sediments. Production rates, production pathways, and monosaccharide composition of water‐soluble (colloidal) carbohydrates, EPS, and intracellular storage carbohydrate (glucans) were investigated in the epipelic (mud‐inhabiting) diatoms Cylindrotheca closterium (Ehrenburg), Navicula perminta (Grün.) in Van Heurck, and Amphora exigua Greg. under a range of experimental conditions simulating aspects of the natural environment. Cellular rates of colloidal carbohydrate, EPS, and glucan production were significantly higher during nutrient‐replete compared with nutrient‐limited growth for all three species. The proportion of EPS in the extracellular carbohydrate pool increased significantly (to 44%–69%) as cells became nutrient limited. Cylindrotheca closterium produced two types of EPS differing in sugar composition and production patterns. Nutrient‐replete cells produced a complex EPS containing rhamnose, fucose, xylose, mannose, galactose, glucose, and uronic acids. Nutrient‐limited cells produced an additional EPS containing mannose, galactose, glucose, and uronic acids. Both EPS types were produced under illuminated and darkened conditions. 14C‐labeling revealed immediate production of 14C‐glucan and significant increases in 14C‐EPS between 3 and 4 h after addition of label. The glucan synthesis inhibitor 2,6‐dichlorobenzonitrile significantly reduced 14C‐colloidal carbohydrate and 14C‐EPS. The glucanase inhibitor P‐nitrophenyl β‐d‐glucopyranoside resulted in accumulation of glucan within cells and lowered rates of 14C‐colloidal and 14C‐EPS production. Cycloheximide prevented glucan catabolism, but glucan production and EPS synthesis were unaffected.
Summer forages under irrigation. 3. The effect of nitrogen fertilizer on the growth, mineral composition and digestibility of a sorghum cross Sudangrass hybrid and Japanese barnyard millet

Sorghum bicolor x S. sudanense hybrid cv. Sudax ST6 and Echinochloa utilis cv. Shirohie were grown under irrigation at Trangie, New South Wales. Six rates of nitrogen (N) fertilizer were applied at sowing: 0, 25, 50, 120, 300, 450 kg N/ha. Height and dry matter yield were recorded at head emergence, together with the leaf hydrocyanic acid (HCN) potential, and leaf and stem dry matter digestibility, nitrogen, sulfur and sodium contents. Both the sorghum hybrid and the millet reached maximum forage yields (16.1 and 7.6 t/ha, respectively) at 350 kg N/ha. However, the tall-growing forage sorghum produced more dry matter than millet and consequently was more responsive to fertilizer nitrogen. In sorghum the leaf HCN potential increased linearly in response to N (8.5 x 10-4 %/kg N.ha). Since there was no compensating increase in the sulfur content (0.072%), and, assuming a requirement of 1.2 g S/g of HCN detoxified, sorghum lacked sufficient sulfur to detoxify the HCN potentially released in the rumen from sorghum receiving 150-200 kg N/ha. At this rate of nitrogen application, sorghum was producing only two-thirds of its forage yield potential. The sodium content of sorghum (0.013%) was not affected by nitrogen. In millet the nitrogen and sodium contents increased as applied nitrogen promoted growth. Plant sulfur was diluted initially but the nitrogen: sulfur ratio increased steadily (0.0067 units/kg N.ha). In contrast to sorghum, therefore, nitrogen fertilizer can be used to increase the dry matter yield of millet without jeopardizing forage quality and hence animal production.
Artificial surfaces as a method of studying populations of benthic micro-algae in fresh water

Most work on the ecology of communities of attached algae has involved the investigation of populations which develop on artificial surfaces exposed in the water for a known period of time. The nature and position of the surface and length of time of exposure have been shown to influence the population which develops. No studies have related the structure of these populations to populations on natural surfaces. Microscope slides which had been exposed in a pond and a stream for two and four weeks were sampled over a period of more than one year, and natural vegetation was sampled at the same time. The populations of attached diatoms on each substrate were analysed. The diatoms in the pond grew mainly in summer on the slides and in winter on the natural host. In the stream the main growth of the population was over the summer period in all cases. There were twice as many species of diatoms growing on natural hosts as on the slides, and the percentage importance of the species was different. The time of yea.
Germinación y dormancia de arbustos y trepadoras del bosque siempreverde de la Sierra del Rosario, Cuba

Se determinaron los requerimientos germinativos y las clases de dormancia seminal en 14 especies de arbustos y 16 trepadoras (13 enredaderas y tres lianas), del bosque siempreverde estacional tropical de la Reserva de la Biosfera Sierra del Rosario, Cuba. Tambien se evaluaron las relaciones entre las clases de dormancia y otros rasgos de historia de vida de las plantas. Los experimentos de germinacion se realizaron en condiciones controladas de laboratorio (luz y temperatura): una temperatura constante de 25 oC, tres condiciones de temperatura alterna (25/30 oC, 25/35 oC y 25/40 oC) y dos ambientes luminicos (luz y oscuridad). En los arbustos, la luz fue el principal factor que regulo la germinacion; mientras que en las trepadoras los factores experimentados no afectaron significativamente la germinacion en su totalidad, aunque algunas tuvieron una respuesta especie-especifica. Solo dos especies fueron totalmente fotoblasticas positivas, y la germinacion a la luz disminuyo con la masa fresca de la semilla. La dormancia ocurrio en 23 especies (76,6 %), de ellas 10 eran arbustos y 13, trepadoras. En los arbustos la dormancia fisiologica fue la mas abundante, y en las trepadoras predominaron la fisiologica y la fisica. Entre las trepadoras se hallaron las unicas especies con dormancia morfologica y/o morfofisiologica. El mayor numero de semillas dormantes se encontro en la estacion seca (87 %). El estudio confirmo la diversidad de mecanismos de dormancia y requerimientos germinativos ya reportados en estas formas de vida para el tropico.
Activity of the Insectivorous Bat Pteronotus parnellii Relative to Insect Resources and Vegetation Structure

Riparian areas often are assumed to be necessary sites for foraging by insectivorous bats because of high insect availability and ease of movement and echolocation in the forest. However, effects of vegetation clutter and insect availability on bat activity have not been compared between riparian and nonriparian areas. We used autonomous recorders to evaluate the effects of vegetation structure, insect mass, and assemblage composition on the activity of the aerial insectivorous bat Pteronotus parnellii along stream channels and nonriparian areas in a tropical rainforest in central Brazilian Amazonia. We quantified vegetation clutter using horizontal photographs, captured nocturnal insects with light traps, and recorded bat activity for 110 nights (1,320 h) in 22 sampling plots. Pteronotus parnellii was more active in sites with dense understory vegetation, which were more common away from riparian zones. Bat activity was related to insect availability (mass and composition), independent of the habitat type. Ability to detect insects on vegetation and avoid obstacles should not restrict the activity of P. parnellii in cluttered sites. This suggests that mass and species composition of insects had stronger influences on habitat use than did vegetation clutter. Pteronotus parnellii probably selects cluttered places as feeding sites due to the availability of higher quality prey. Áreas ripárias são muitas vezes consideradas locais necessários para o forrageio por morcegos insetívoros por causa da alta disponibilidade de insetos e facilidade de movimento e recepção da ecolocalização na floresta. No entanto, os efeitos da obstrução da vegetação e disponibilidade de insetos sobre a atividade de morcegos não têm sido comparados entre as áreas ripárias e não ripárias. Nós usamos gravadores autônomos de ultrassom para avaliar os efeitos da estrutura da vegetação, massa e composição da assembleia de insetos sobre a atividade do morcego insetívoro aéreo Pteronotus parnellii ao longo do canal central de riachos e áreas não ripárias em uma floresta tropical na Amazônia central brasileira. Nós quantificamos a obstrução da vegetação usando fotografias horizontais da floresta, capturamos os insetos noturnos com armadilhas luminosas e gravamos a atividade dos morcegos durante 110 noites (1.320 h) em 22 pontos de amostragem. Pteronotus parnellii foi mais ativo em locais com vegetação arbustiva densa, que foram mais comuns longe das zonas ripárias. A atividade dos morcegos foi relacionada com a disponibilidade de insetos (massa e composição), independente do tipo de habitat. A capacidade de detectar insetos sobre a vegetação e evitar obstáculos não deve restringir a atividade de P. parnellii em locais obstruídos. Isto sugere que a massa e a composição de espécies de insetos tiveram forte influência sobre o uso do habitat do que a obstrução da vegetação. Pteronotus parnellii provavelmente seleciona lugares obstruídos como locais de alimentação devido à disponibilidade de presas de maior qualidade.
Recent advances in the role of organic acids in poultry nutrition

ABSTRACT In recent years, there has been an increase in the use of organic acids as substitutes for antibiotic growth promoters because of the fear of antibiotic resistance and the implications for human health. Organic acids and their salts have been used in poultry diets and drinking water for decades and seem to elicit a positive response in growth performance. An important objective of dietary acidification is the inhibition of intestinal bacteria competing with the host for available nutrients, and a reduction of possible toxic bacterial metabolites resulting in the improvement of nutrient digestibility, thereby ameliorating the performance of birds and enhancing the specific and non-specific immunity in poultry. Literature shows that short-chain fatty acids, medium-chain fatty acids and other organic acids have more or less pronounced antimicrobial activity, depending on both the concentration of the acid and the bacterial species that is exposed to the acid. The possible mechanisms contributing to these effects and the factors thought to explain the variability in these responses are discussed. This paper provides a review of the use of organic acids in the prevention of enteric disease in poultry, the effect on the gastrointestinal tract, nutrient digestibility, immunity and performance of broiler and laying hens.