Miracle-dz/UniFAR-FTUs huggingface dataset:
Maternal genes required for the anterior localization of bicoid activity in the embryo of Drosophila

The maternal gene b ico id (bcd) organizes anterior development by means of an activity localized at the anterior tip of the embryo. The mutant phenotypes of s w a l l o w s w a and exuperan t ia (exu) share with weak b c d alleles the lack of anterior head structures. Cytoplasmic transplantations reveal a much reduced b c d + activity at the anterior tip of s w a and exu embryos. In contrast to weak b c d alleles, removal of anterior cytoplasm has very little effect on the s w a or exu phenotype. We suggest that in embryos mutant for exu or s w a the b c d activity is not restricted to the anterior tip but extends toward more posterior positions. These conclusions are supported by changes in the fate maps of bcd, exu, and s w a mutant embryos and by the ectopic expression of anterior structures in certain double-mutant phenotypes.
On the Origin and Diagnostic Criteria of Olfactory Neuroblastoma

The origin and diagnostic criteria of olfactory neuroblastoma are still under dispute. Tosolve these problems, seven cases of olfactory neuroblastomas satisfying diagnostic criteria of Choi and Anderson were analyzed immunohistochemically by using antibodies to markers expressed in developing and mature human olfactory placode-derived neurons such as keratin, a 34 kDa epithelial membrane glycoprotein, luteinizing-hormone-releasing-hormone (LHRH) and to other neural tissue markers. Ultrastructural analysis was also carried out. Five cases were identified as neuroblastomas because neurites were disclosed in them. All of these five cases had widespread immunoreactivity to an antibody to a 34 kDa epithelial membrane glycoprotein (Ber-EP4) in the tumor cell bodies and/or neuritic processes. They also contained keratin positive cells. LHRH was demonstrated in two of these Ber-EP4 positive neuroblastomas. The spectrum of immunohistochemical findings of these five cases was identical to the normal neuroblasts arising from olfactory placode.Accordingly, it is concluded that neuroblastoma of true olfactory placodal origin does exist. The diagnostic criteria of this tumor is as follows: demonstration of neurites and immunoreactivity to Ber-EP4 and/or LHRH. Keratin is not necessary to regard as an evidence of epithelial differentiation in this tumor.
Worker Reproduction in the Higher Eusocial Hymenoptera

Worker reproduction (i.e., the parthenogenetic production by workers of males and, more rarely, females) is very widespread in the higher eusocial Hymenoptera (bumble bees, stinglees bees, honey bees, vespine wasps, higher ants). Examples are given in the text. The mutualistic theory ("hopeful reproductive" hypothesis) of hymenopteran eusociality (semisocial route) states that the first workers were reproductive because the possibility of future reproduction was the condition for their originally working. In Hamilton's kinship theory (subsocial route) workers produce males on account of their greater relatedness to sons than to brothers. Several recent models indicate that worker male production could have facilitated the evolution of eusociality. Queen control (queen inhibition of worker fertility) arises because queens are more closely related to their own than to workers' offspring, and explains why present-day workers are most reproductive in queenless conditions. Conversely worker reproduction in queenright colonies (i.e., colonies containing the maternal queen) reflects selection on workers to evade queen control Optimization models predict that workers should produce all or none of a colony's males. Although workers in some species produce 100 per cent of the males, reproductive workers more usually produce an extremely variable proportion of males. When workers reproduce, the expected equilibrium sex ratios change; but the information needed to assess the importance for sex-ratio determination of worker male production is lacking. Kinship theory suggests that polygyny (multiple queens) and multimple mating both promote queeright worker reproduction by reducing intracolony genetic relatedness. The analysis of data assembled on 49 ant species reveals that workers in monogynous species (i.e., with one queen per colony) reproduce moslty in queenless conditions, whereas those in polygynous species reproduce in queenless and queenright conditions equally often, in agreement with kinship theory. Monogyny could favor a reproductive worker caste becuse the high probability of colony orphanage allows workers greater opportunity to reproduce free from queen control. The ability of workers to reproduce has important consequence for colony organization and function. These include (1) the extent and nature of queen control of worker fertility, such control being viewed as the outcome of an "arms race" with workers over male parentage; (2) the occurrence of dominance behavior, egg cannibalism, brood destruction, and possibly even matricide in colonies with reproductive workers; (3) reduced colony efficiency and the system of temporal division of labor based on worker age and ovarian development; and(4) the rarity of physical castes among workers. For all these reasons, worker reproduction is crucial to our understanding of hymenopteran eusociality.
Effect of glycerol on the lipids in the red alga Gratelupia doryphora .

The red alga Gratelupia doryphora was cultivated in Provasoli enricher (plain) seawater and in a glycerol media. The incubation in seawater leads to an increase in the percentage of polyunsaturated acids, while the glycerol increase the total lipid content. If the alga is being grown as a heterotrophic culture, it is possible to increase the alga biomass as well as the content of biologically-active fatty acids.
Isolation and partial characterisation of dehalogenase-deficient mutants of a Rhizobium sp.

A fast-growing species of Rhizobium that can utilise 2,2-dichloropropionate and 2-chloropropionate as sole sources of carbon and energy was mutated to give strains which had lost this ability. Such mutants lacked two inducible dehalogenase activities that were present in the parent organism. Secondary mutants which had regained the ability to grow on 2,2-dichloropropionate (2,2DCP) and/or 2-chloropropionate (2CP) were isolated from the original mutants. Some were constitutive for dehalogenase I and did not form dehalogenase II, some were constitutive for dehalogenase II and did not form dehalogenase I, whilst others, like the parent organism, formed both dehalogenases inducibly. A possible model for the control of dehalogenase synthesis is proposed.
Variability in timing of egg hatch of Triaenophorus crassus Forel (Cestoda: Pseudophyllidea) as a mechanism increasing temporal dispersion of coracidia

Eggs collected from 174 Triaenophorus crassus Forel over 3 years were maintained under a 12-h photocycle at 15 °C to quantify variability in three egg hatching characteristics. The percentage of eggs hatching to release coracidia varied from 20 to 90% (mean 82%). The median hatch time (time from egg release to hatch) varied from 4.3 to 14.2 days (mean 8.3 days). The duration of the egg hatching period (the time between hatch of 10 and 90% of eggs) varied from 1 to 17 days (mean 4.6 days). These three characteristics varied among years, among worms from different hosts, and among worms from the same host. Variability in egg hatching characteristics was not correlated with egg size or fecundity of the parent, but a consideration of this variability within the context of the hierarchical nature of parasite populations suggested that this variability resulted from genotypic and environmental contributions to parasite phenotype. Results of a simulation study suggested that naturally occurring levels of variabi.
Efeito da massagem do úbere ao final da ordenha no leite residual e na ocorrência de mastite em vacas leiteiras

O leite residual (LR) pos-ordenha e um importante fator predisponente de mastite. Neste estudo foi testada a hipotese de que a massagem do ubere ao final da ordenha pode reduzir o LR e a incidencia de mastite. Para tanto foram realizados dois experimentos, o experimento 1 foi realizado numa fazenda experimental com 10 vacas (6.200kg/lactacao) e o experimento 2 em fazenda comercial com 52 vacas (4.480kg/lactacao). Em ambos os experimentos as vacas foram pareadas por numero de partos, estagio de lactacao e produtividade e aleatoriamente destinadas a um dos tratamentos: com massagem ou sem massagem do ubere, em duas etapas num desenho “cross-over”. A producao de leite individual de cada vaca foi medida. O leite residual foi coletado e medido 2min apos aplicacao de ocitocina intravenosa. Foi usado o California Mastite Teste (CMT) para detectar mastite subclinica. Em ambos os experimentos a massagem nao teve efeito na producao de leite (experimento 1, p > 0,41, n = 10; e experimento 2, p > 0,46, n = 12), nem no LR (experimento 1, 1,78 ± 0,45kg, n = 10; experimento 2, 2,42 ± 0,32kg, n = 12), e nem na incidencia de mastite (experimento 2, qui-quadrado, p > 0,68, n = 26). Concluiu-se que, nas condicoes do experimento, a massagem no ubere nao teve efeito no LR e nem na incidencia de mastite.
Calculation of Vertical Transmission Rates of Infection, Illustrated with Data on an Aphid-Borne Virus

seems reasonable to consider that dominant birds join subordinant birds to parasitize them when any food is found, and thus, in a sense, subordinants are captive in flocks but may be good food finders. Another possibility is that in natural situations the food patches are large enough that low-ranking birds can get more food than isolates. Perhaps this is analogous to the observation of Krebs et al. that sometimes the low-ranking birds fed on food dropped by more dominant birds. In any case, an experiment in which patch size was a variable would be interesting in this regard. Returning to the probability estimates of P7 and P8, one could argue for the elimination of P2 from the calculations because for subordinants it can be considered that Probability of being subordinant = 1 and similarly for dominants. Thus revised, P7 = 1 and P8 = 2, which does not change the conclusions. A note of qualification is necessary here. Sometimes birds that were "prevented" actually were able to obtain crumbs from the floor that were dropped by higher-ranking birds. These were also included as feeders in Krebs et al.'s table 1. To determine the adaptive significance of flocking, it seems preferable to assume that in a natural situation the reliability of obtaining crumbs would be quite low, so I count these individuals as not finding food in the sense meant by the experiment or in the sense implied in the interpretations of Krebs et al.
Mapping Quantitative Trait Loci for Partial Resistance to Powdery Mildew in an Australian Barley Population

Genomic regions influencing resistance to powdery mildew [Blumeria graminis (DC.) E.O. Speer f. sp. hordei Em. Marchal] were detected in a doubled haploid (DH) barley (Hordeum vulgare L.) population derived from a cross between the breeding line ND24260 and cultivar Flagship when evaluated across four field environments in Australia and Uruguay. Significant quantitative trait loci (OIL) for resistance to B. graminis were detected on six of the seven chromosomes (1H, 2H, 3H, 4H, 5H, and 7H). A QTL with large effect donated by ND24260 mapped to the short arm of chromosome 1H (1 HS) conferring near immunity to B. graminis in Australia but was ineffective in Uruguay. Three OIL donated by Flagship contributed partial resistance to B. graminis and were detected in at least two environments. These OIL were mapped to chromosomes 3H, 4H, and 5H (5HS) accounting for up to 18.6, 3.4, and 8.8% phenotypic variation, respectively. The 5HS QTL contributed partial resistance to B. graminis in all field environments in both Australia and Uruguay and aligned with the genomic region of Rph20, a gene conferring adult plant resistance (APR) to leaf rust (Puccinia hordei Otth), which is found in some cultivars having Vada' or 'Emir' in their parentage. Selection for favorable marker haplotypes within the 3H, 4H, and 5H QTL regions can be performed even in the presence of single (major) gene resistance. Pyramiding such QTL may provide an effective and potentially durable form of resistance to B. graminis.
Effect of Salmon Carcass Decomposition on Lake Superior Tributary Streams

We investigated the fate of organic matter and inorganic nutrients derived from spawning runs of chinook salmon in tributary streams to Lake Superior during fall and winter 1990. Upstream-downstream comparisons and experimental introduction of carcasses were used to determine how salmon carcass decomposition influenced several stream ecosystem components, including total phosphorus, total nitrogen, soluble reactive phosphorus (SRP), NO3-, NH4+, periphyton biomass, and fine particulate organic matter (FPOM) in transport. Total phosphorus, SRP, and periphyton biomass were higher in a river reach that received a spawning run of an estimated 1200 fish than in an upstream reach that lacked spawning salmon. No upstream-downstream gradient in these components occurred in a river that did not receive a spawning run. Total phosphorus, SRP, and periphyton also were elevated where we experimentally introduced salmon carcasses, in the absence of a natural salmon run. Stable isotope analyses revealed that salmon-derived nitrogen was incorporated into grazing mayflies, and to a lesser extent into filter-feeding caddisflies. Salmon-derived carbon was not incorporated into these macroinvertebrates. These results show that salmon carcasses can be an important source of nutrients in streams even when runs are relatively small.
Long‐term post‐fire changes in the northeastern boreal forest of Quebec

Natural dynamics in the boreal forest is influenced by disturbances. Fire recurrence affects community development and landscape diversity. Forest development was studied in the northeastern boreal forest of Quebec. The objective was to describe succession following fire and to assess the factors related to the changes in forest composition and structure. The study area is located in northeastern Quebec, 50 km north of Baie-Comeau. We used the forest inventory data gathered by the Ministere des Ressources naturelles du Quebec (MRNQ). In circular plots of 400 m2, the diameter at breast height (DBH) of all stems of tree species greater than 10 cm was recorded and in 40 m2 subplots, stems smaller than 10 cm were measured. A total of 380 plots were sampled in an area of 6000 km2. The fire history reconstruction was done based on historical maps, old aerial photographs and field sampling. A time-since-fire class, a deposit type, slope, slope aspect and altitude were attributed to each plot. Each plot was also described according to species richness and size structure characteristics. Traces of recent disturbance were also recorded in each plot. Changes in forest composition were described using ordination analyses (NMDS and CCA) and correlated with the explanatory variables. Two successional pathways were observed in the area and characterized by the early dominance of intolerant hardwood species or Picea mariana. With time elapsed since the last fire, composition converged towards either Picea mariana, Abies balsamea or a mixture of both species and the size structure of the coniferous dominated stands got more irregular. The environmental conditions varied between stands and explained part of the variability in composition. Their effect tended to decrease with increasing time elapsed since fire, as canopy composition was getting more similar. Gaps may be important to control forest dynamics in old successional communities.
Morphological Variation in Three Species of the Genus Ceramium (Ceramiales, Rhodophyta) from Hawaii: Differences between Reproductive Phases and Phenotypic Plasticity

The genus Ceramium Roth shows a high degree of morphological variability within some of its species. As reported in several descriptions, this variability has been experimentally examined in only a few cases where it has been shown to be the result of environmental influences or, it has been detected between tetrasporophytic and gametophytic generations. In order to examine the effect of environmental factors upon the morphology of different phases of the life cycle of the genus, three conspicuous species from Hawaii were cultured under controlled conditions and compared with field-grown plants. Ceramium clarionensis Setchell et Gardner, Ceramium flaccidum (Kutzing) Ardisonne and Ceramium sp. 1 showed different results for a number of characters assessed under the same conditions
Shelf life extension of ground meat stored at 4 °C using chitosan and an oxygen absorber

Summary The combined effect of chitosan (1%) and an oxygen absorber on shelf life extension of fresh ground meat stored at 4 °C was investigated. Parameters monitored over a 10-day storage period were Total Viable Count (TVC), Pseudomonas spp. , Brochothrix thermosphacta, lactic acid bacteria, Enterobacteriaceae, pH, thiobarbituric acid (TBA), colour, odour and taste. Microbial populations were reduced by 0.4–2.0 log CFU g−1 for a given sampling day using either chitosan or the oxygen absorber, with the more pronounced effect being achieved by the combination of two. Thiobarbituric acid values for all samples increased during storage with the exception of samples treated with both chitosan and the oxygen absorber in which Thiobarbituric acid values decreased. Changes in pH values with time/different treatments were statistically insignificant. Colour parameters were affected by most treatments. On the basis of microbiological and sensory evaluation, a shelf life extension of 5–6 days was obtained for samples treated with the chitosan and the oxygen absorber combination.
The influenceof hexactinellid sponge (Pheronema carpenteri) spicules on the patchy distribution of macrobenthos in the porcupine seabight (bathyal ne atlantic)

Abstract The hexactinellid sponge Pheronema carpenteri occurs in high densities (1.5 m−2) over a narrow bathymetric range (1000–1300 m) in the Porcupine Seabight, to the southwest oflreland. The possible influence of sponge spicule mats, which may cover ⅓ of the seafloor, on macrobenthic communities is assessed. Three box core samples were collected from the high density sponge zone (1250 m) and three cores were taken at each of two comparative non-sponge stations (900 and 1500 m). Analysis of data on the abundance and taxonomic composition of major groups of the larger (> 1 mm) macrobenthos suggests that the presence of sediment surface sponge spicule mats substantially modifies the fauna at the 1250 m station. The numerical abundance of macrobenthos within this station increases in an almost linear fashion with the volume of spicules present in a sample; in a single sample with the highest spicule volume, abundance was nearly an order of magnitude higher than that expected in the absence of spicule mats.
Belowground Carbon Allocation in Forest Ecosystems: Global Trends

Carbon allocation to roots in forest ecosystems is estimated from published data on soil respiration and litterfall. On a global scale, rates of in situ soil respiration and aboveground litter production are highly and positively correlated, suggesting that above- and belowground production are controlled by the same factors. This relationship also allows us to predict rates of total soil respiration and total carbon allocation to roots in forest ecosystems from litterfall measurements. Over a gradient of litterfall carbon ranging from 70 to 500 g m-2 yr-1, total belowground carbon allocation increases from 260 to 1100 g m-2 yr-1. The ratio of belowground carbon allocation to litterfall decreases from 3.8 to 2.5 as litterfall carbon increases from 70 to 200 g.m-2 yr-1, but changes little (2.5 to 2.2) as litterfall carbon increases from 200 to 500 g.m-2 yr-1. Use of this relationship permits the construction of simple carbon budgets that can be used to place upper limits on estimates of fine root production in forest ecosystems. Determining live-root respiration rates in forest ecosystems will further constrain the range of possible root production rates.
Predicting the potential distribution of plant species in an alpine environment

The relationships between the distribution of alpine species and selected environmental variables are investigated by using two types of generalized linear models (GLMs) in a limited study area in the Valais region (Switzerland). The empirical relationships are used in a predictive sense to mimic the potential abundances of alpine species over a regular grid. Here, we present the results for the alpine sedge Carex curvula ssp. curvula. The modelling approach consists of (1) a binomial GLM, including only the mean annual temperature as explanatory variable, which is adjusted to species presence/absence data in the entire study area; (2) a logistic model restricted to stands occurring within the a priori defined temperature range for the species - which allows ordinal abundance data to be adjusted; (3) the two species-response functions combined in a GIS to generate a map of the species' potential abundance in the study area; (4) model predictions filtered by the classes of the qualitative variables under which the species never occur. Such a stratified approach used to better fit the variability within the optimal altitudinal zone for the species. Removing stand descriptions from altitudes too high or too low, where the species is unlikely to occur, enhances the global modelling performance by allowing the identification of important environmental variables only retained in the second model. The model evaluation is finally carried out with the γ-measure of association in an ordinal contingency table. It shows that abundance is satisfactorily predicted for C. curvula.
The Position of Turkey, Chicken, Pheasant, and Partridge Embryos That Failed to Hatch

Abstract THE long axis of the avian embryo in the normal hatching position coincides with that of the egg, the beak being under the right wing with the tip of the beak towards the air cell in the large or blunt end. Sanctuary (1925) pointed out that many embryos that fail to hatch are not in the normal hatching position and that this may be a factor in their failure to hatch. He reported the frequency of three malpositions, one of which had been observed by Reamur in 1751 (Hutt and Pilkey, 1934). Further observations have since been reported by Hutt (1929), Smith (1930), Hutt and Cavers (1931), and others. The causes that determine the final position of the embryo in the egg have been investigated. Taylor (1932) found that a larger proportion of the malposition head in small end of egg occurred when the 6-day-old embryos were improperly oriented, than .
The stomatal apparatus of Lycopodium japonicum and its bearing on the stomata of the Devonian lycophyte Drepanophycus spinaeformis

The structure of the stomatal apparatus of the leaf of Lycopodium japonicum Thumb was studied using epidermal macerations, sections and scanning electron microscopy. The stomatal apparatus of L. japonicum consists of two large guard cells and pore, and is anomocytic. Based on light microscopy, the impression from epidermal macerations that there were two small guard cells surrounded by two, large, similarly shaped, subsidiary cells (paracytic) derives from a pronounced elliptical cuticular ledge on the surface of the guard cells surrounding a thickened circumporal area. A similar appearance is characteristic of cuticle preparations of the Devonian lycophyte Drepanophycus spinaeformis Goppert. We therefore conclude, as did W.H. Lang over 70 years ago, that the stomata of the early lycophyte were also anomocytic, as were those of a second species of Drepanophycus, D. qujingensis.