Miracle-dz/UniFAR-FTUs huggingface dataset:
Frequency-Dependent Selection in Randomly Mating Populations

A general model which accommodates different fitness values of an individual in association with each other type of individual is studied. The model in conjunction with population composition, in which individuals are assumed to be dispersed at random, determines the relative fitness values of individuals. Expressions for the change in gene frequency and for the mean are derived for one locus with two alleles in a random mating population. Equilibrium and max/min mean compositions generally require solving third-degree equations, but explicit expressions are found for models with general levels of dominance and some of their variants. Protected polymorphisms, genetic loads, inbreeding depressions, and the cost of a gene substitution are also considered. Many additional features of the statics and dynamics of populations are introduced with the effects of population composition on fitnesses. A single globally stable equilibrium can exist without any dominance. There may be multiple equilibria, up to three, with various stability characteristics, some of which are protected polymorphisms. There need not be any correspondence between compositions for max/min means and those for equilibria. Inbreeding depressions may be curvilinear, and even stable equilibrium populations may show negative inbreeding depressions. Very different models may give the same genetic load. The number of genetic deaths required for a gene substitution may be as few as twice the population size. One appeal of the model is that it encompasses several classes of models, including those with constant fitness values, and thus provides a basis for determining the appropriate model. After considering alternative experiments and measures of discrimination, we conclude that only survival values of the genotypes for several population compositions would be sufficient to discriminate between certain models.
Survival of Arbuscular Mycorrhizal Fungi Following Reciprocal Transplanting Across the Great Basin, USA

Mycorrhizal fungi are transplanted into exotic habitats to aid in agriculture and land restoration. However, different taxa have different effects on hosts, and little is known about their survival or spread. The fate of arbuscular mycorrhizal fungi was examined in a reciprocal transplant experiment of a single host shrub species, Artemisia tridentata subspecies tridentata between two semiarid sites. The sites were located near Reno, Nevada, and San Diego, California, in the western United States. The experiment was a complete factorial design: two plant populations, A. tridentata ssp. tridentata from the Reno and the San Diego sites, and five fungal treatments (Acaulospora elegans from San Diego, Scutellospora calospora from Reno, a whole-soil inoculum from San Diego, a whole-soil inoculum from Reno, and uninoculated soil). Based on fluorescein isothiocyanate-labeled antiserum studies, neither fungus declined over three growing seasons at the site of origin with the plant population of origin. Survival of the fungi always declined in association with the exotic host population and at the exotic site. Spore density of fungi that had been inoculated was generally very low. However, when significant differences between treatments were observed, spore density of the fungus was higher in association with plants that had been inoculated with it than with uninoculated plants, and the fungus had higher survivorship in the site and with the host of its origin. Both fungi usually sporulated more often under inoculated than uninoculated host plants. Over three growing seasons, both A. elegans and S. calospora survived in their sites of origin and in the exotic location with both plant populations. The fungi spread throughout the root systems and between plants of the different treatments. These results show that, while there was higher survival by the arbuscular mycorrhizal fungi at the site and with the host of origin, these fungi survived and spread for at least three growing seasons, although they declined significantly at the exotic site and with exotic hosts.
MO25α/β interact with STRADα/β enhancing their ability to bind, activate and localize LKB1 in the cytoplasm

Mutations in the LKB1 protein kinase result in the inherited Peutz Jeghers cancer syndrome. LKB1 has been implicated in regulating cell proliferation and polarity although little is known about how this enzyme is regulated. We recently showed that LKB1 is activated through its interaction with STRADα, a catalytically deficient pseudokinase. Here we show that endogenous LKB1–STRADα complex is associated with a protein of unknown function, termed MO25α, through the interaction of MO25α with the last three residues of STRADα. MO25α and STRADα anchor LKB1 in the cytoplasm, excluding it from the nucleus. Moreover, MO25α enhances the formation of the LKB1–STRADα complex in vivo, stimulating the catalytic activity of LKB1 ∼10‐fold. We demonstrate that the related STRADβ and MO25β isoforms are also able to stabilize LKB1 in an active complex and that it is possible to isolate complexes of LKB1 bound to STRAD and MO25 isoforms, in which the subunits are present in equimolar amounts. Our results indicate that MO25 may function as a scaffolding component of the LKB1–STRAD complex and plays a crucial role in regulating LKB1 activity and cellular localization.
Inhibition of the rumen anaerobic fungus Neocallimastix frontalis by fermentation products

The effects of bacterial fermentation products on cellulose degradation by the rumen fungus Neocallimastix frontalis have been investigated. H2, formate, lactate and ethanol were strong inhibitors, particularly at high concentrations. Acetate and malate also inhibited, whereas succinate had a variable effect. Butyrate and propionate had no inhibitory effects.
The influence of yeast strains on the volatile flavour compounds of Chinese rice wine

In order to assess the influence of yeast strains on volatile flavour profiles of Chinese rice wine, small-scale Chinese rice wine brewing was carried out with eight yeast strains from three different typical Chinese rice wine brewing regions. The volatile flavour compounds were extracted by headspace solid phase microextraction (HS-SPME) and analyzed by gas chromatography-mass spectrometry (GC-MS). The volatile flavour profiles of the different Chinese rice wines showed statistically significant differences depending on the yeast strains used. Yeast strains from the Shaoxing region showed a higher capacity to produce the esters 2-phenylethanol and 3-methylthiopropanol, while yeast strains from the Shanghai region stood out for their production of branched-chain higher alcohols. Chinese rice wine fermented with a yeast strain from the Jiangsu region had the highest levels of organic acids. Using principal component analysis of the Chinese rice wine volatile flavour compounds, the eight yeast strains could be classified into three groups according to their origins. This is the first report about the volatile flavour characteristics of Chinese rice wine yeast. The data obtained in this work shows that the yeast strains contributed significantly to the flavour differences of the Chinese rice wines from the different regions.
INFREQUENT ESTABLISHMENT OF SEEDLINGS OF AGAVE DESERTI (AGAVACEAE) IN THE NORTHWESTERN SONORAN DESERT

Survival of seedlings of the common desert succulent, Agave deserti, required unusually wet years and the protection afforded by nurse plants or other shelters. The characteristics of seed germination and of seedlings showed that water stress in the seedling stage may be the most important factor affecting establishment. Leaves wilted irreversibly at an osmotic potential of -1.6 MPa (-16 bars). Survival of seedlings required the generation of enough biomass during the first wet season to survive drought periods when the water potential of the soil was below -1.6 MPa. Lengths of individual growing seasons and subsequent droughts were obtained from rainfall records for 1961 through 1978 for a site in the western Colorado desert. The length of the first major drought following germination apparently limited establishment of Agave deserti to only one year in the last 17. The favorable year, 1967, was consistent with the estimated year of germination of the six smallest Agave deserti observed in 1,500 m2 at the field site. WATER RELATIONSHIPS play a critical role in the survival of the seedling stage of desert succulents. Their roots are often quite shallow (Steenbergh and Lowe, 1969; Nobel, 1976), and so during an extended drought the seedlings can obtain no water from the soil. To survive such a dry period, the seedlings must develop sufficient water storage tissue during the previous wet season. Desert succulents exhibit Crassulacean acid metabolism (CAM), characterized by nocturnal stomatal opening and CO2 uptake (Nishida, 1963; Nobel, 1976). Although important for water conservation, CAM is associated with slow growth rates, e.g., Carnegiea gigantea grew only 1.3 cm
Convergent Total Syntheses of Oligosaccharides by One-Pot Sequential Stereoselective Glycosylations

A convergent total synthesis of F1α antigen, a member of the tumor-associated O-linked mucin glycosyl amino acid, was tried by one-pot sequential glycosylation. Highly α-selective glycosylation of amino acid 7 with thioglycoside 6 was successfully carried out by combining trityl trifluoromethanesulfonate (TrOTf) and N-iodosuccimide (NIS) which gave glycosyl amino acid 21 in high yield (97%, α/β = 83⁄17). Next, the glycosylation of thioglycoside 4 with galactosyl phenyl carbonate 2 or fluoride 3 was tried by the promotion of trityl tetrakis(pentafluorophenyl)borate [TrB(C6F5)4] or trifluoromethanesulfonic acid (TfOH); protected F1α 25 was afforded in 80 or 89% overall yield, respectively, by the further addition of glycosyl amino acid 5 and NIS. The desired trisaccharide was obtained in high yield after removal of the protecting groups. Next, a convergent total synthesis of branched hepta-β-glucoside 30 having phytoalexin-elicitor activity was efficiently performed by way of two one-pot sequential glycosyl.
Pressure–volume analysis of leaves of Robiniapseudoacacia L. with the sap expression and free transpiration methods

Leaf tissue water relations parameters of well-watered and drought-stressed black locust (Robiniapseudoacacia L.) seedlings were compared using the sap expression and free transpiration pressure–volume analysis techniques. Osmotic potentials at full tissue hydration and at the turgor loss point were higher using the sap expression method for well-watered but not for drought-stressed seedlings. These differences appeared to be related to the percentage of water left uncollected during the sap expression procedure. Osmotic adjustment in response to drought was detected by both methods. Leaf relative water content at the turgor loss point and the symplastic water fraction did not differ between methods. The relationship between bulk tissue elastic modulus (E) and turgor potential estimated by both techniques was not significantly different, although E values derived from sap expression curves for well-watered seedlings were generally higher at a given turgor potential.
Speciation as a Stage in Evolutionary Divergence

By speciation is meant the fixation of discontinuity among organisms. Discontinuity is maintained by isolating mechanisms that prevent the interbreeding of carriers of different adaptive complexes of genes. A theory is suggested according to which the development of isolating mechanisms follows, rather than accompanies, that of the adaptive complexes themselves. The development of physiological isolation takes place principally along the geographical boundaries separating the distribution areas of the incipient species. Some evidence for and against this theory is discussed.
Detection of a Methylcarbamate Degradation Gene in Agricultural Soils Using PCR Amplification of Bacterial Community DNA

The carbamate insecticide carbofuran (2,3-dihydro-2,2-dimethyl-7-benofurayl-N-methylcarbamate) is biodegraded by a methylcarbamate hydrolase enzyme encoded by a methylcarbamate degradation (mcd) gene cloned from Achromobacter sp. strain WM111. A 0.4-kbp BamHI-KpnI fragment of the mcd gene was used as a DNA probe to monitor soil microbial populations capable of degrading carbofuran in soils from twelve contrasting agricultural sites, representing seven soil series from five U.S. states. Each soil was amended three times with carbofuran (200 μg g−1 dry weight soil) and monitored until 90% of the carbofuran had degraded after each application. Soil bacterial community DNA was extracted and humic acid contaminants removed prior to PCR amplification of mcd. The detection limit for the probe protocol was 102 microorganisms g−1 of soil. Eight soils were mcd positive, and four were negative. Results were independently confirmed using both a Southern blot and slot blot protocol. Of the four negative soils, three exhibited accelerated rates of carbofuran degradation, suggesting that enzymes other than the hydrolase encoded by mcd were active in pesticide removal.
THE CONTRIBUTION OF INSULATION CHANGES TO THE ENERGY COST OF AVIAN MOLT

To evaluate the contribution of changes in plumage insulation to the energy cost of molt, we measured oxygen consumption by wintering White-crowned Sparrows (Zonotrichia leucophrys gambelii) before and after plucking 12, 24, or 36% of their plumage, and when they were replacing these feathers. Measurements were made at 20 and 25 °C, two temperatures bracketing the lower critical temperature (ca. 23 °C) of wintering Z. l. gambelii, and at 10 °C, well below the birds' lower critical temperature. For comparison, oxygen consumption by naturally molting birds was measured at 25 °C during summer. In these sparrows, feather loss resulted in increased oxygen consumption only at 10 °C and when feather loss was moderate (24% plumage; 10% increase) to intensive (36% plumage; 24% increase). Regrowth of 24 and 36% of plumage resulted in increased oxygen consumption at 20 °C (10 and 8.5%, respectively) and 10 °C (16 and 28%, respectively). Oxygen consumption by birds was unaffected by loss or regrowth of 12% of the plu.
Carbon dioxide balance of a tropical peat swamp forest in Kalimantan, Indonesia

Tropical peatlands, which coexist with swamp forests, have accumulated vast amounts of carbon as soil organic matter. Since the 1970s, however, deforestation and drainage have progressed on an enormous scale. In addition, El Niño and Southern Oscillation (ENSO) drought and large‐scale fires, which grow larger under the drought condition, are accelerating peatland devastation. That devastation enhances decomposition of soil organic matter and increases the carbon release to the atmosphere as CO2. This phenomenon suggests that tropical peatlands have already become a large CO2 source, but related quantitative information is limited. Therefore, we evaluated the CO2 balance of a tropical peat swamp forest in Central Kalimantan, Indonesia, using 3 years of CO2 fluxes measured using the eddy covariance technique from 2002 through 2004. The forest was disturbed by drainage; consequently, groundwater level (GL) was reduced. The net ecosystem CO2 production (NEP) measurements showed seasonal variation, which was slightly positive or almost zero in the early dry season, and most‐negative late in the dry season or early the rainy season. This seasonality is attributable to the seasonal pattern of climate, tree phenology and fires. Slightly positive NEP resulted from smaller ecosystem respiration (RE) and larger gross primary production (GPP) under conditions of high photosynthetic photon flux density (PPFD) and large leaf area index (LAI). The most‐negative NEP resulted from smaller GPP and larger RE. The smaller GPP was related to high vapor pressure deficit (VPD), small LAI and low PPFD because of smoke from fires. The larger RE was related to low GL. Annual NEP values were estimated respectively as −602, −382 and −313 g C m−2 yr−1 for 2002, 2003 and 2004. These negative NEP values show that the tropical peat swamp forest, disturbed by drainage, functioned as a CO2 source. That source intensity was highest in 2002, an ENSO year, mainly because of low PPFD caused by dense smoke emitted from large fires.
Levels of Pancreatic Glucagon, Insulin and Glucose during Twenty-Four Hours of the Day in Normal Subjects

SummarY Plasma pancreatic glucagon, insulin and glucose were mea sured hourly in four healthy adult subjects during 24 hrs of the day. Plasma glucose and insulin levels increased after each meal and were invariable during night. The increase of plasma insulin after supper was not so remarkable as that after breakfast irrespective of its higher blood sugar level confirming a lower glucose tolerance in the evening. Plasma pancreatic glucagon showed a fairly constant level during day and night in normal subjects just as the total glucagon level reported by others.
Can commercial fishing cause evolution? Answers from guppies (Poecilia reticulata)

Life history theory predicts that high adult mortality rates select for earlier maturity and increased reproduc- tion. If such evolution occurs in response to the commercial exploitation of natural fish populations, then the correlated reduction in body size would reduce the yield of the fishery. Earlier maturity and reduced body size are seen in com- mercially exploited populations. Here, we compare the life histories of natural populations of guppies (Poecilia reticulata) from Trinidad that live in either high- or low-predation environments, which serve as surrogates for the presence or absence of commercial fishing. We can quantify mortality rate and life history variables, including age and size at maturity, in the laboratory and in nature. We have manipulated mortality rates in nature and measured the rate of evolution. High mortality selects for earlier maturity at a smaller size, as observed in commercial fisheries and as predicted by theory. Furthermore, the nature and magnitude of predator-induced mortality are comparable to those caused by commercial fishing. The rate of evolution in guppies predicts similar evolution in commercial fisheries on a time scale of decades. These attributes support arguments that humans, like predators, have acted as an agent of selec- tion when exploiting populations of fish. Resume : La theorie demographique predit qu'une forte mortalite des adultes entraine la selection d'une maturite precoce et d'une reproduction accrue. Si une telle selection se produisait en reaction a l'exploitation commerciale des populations naturelles de poissons, la reduction de la taille corporelle, un effet en correlation, reduirait le rendement de la peche. La maturation precoce et la taille reduite s'observent dans les populations exploitees commercialement. Nous comparons ici les cycles biologiques de populations naturelles de guppys (Poecilia reticulata) de Trinidad qui vivent dans des milieux de forte ou de faible predation, ce qui sert ici de phenomene de remplacement pour la presence ou l'absence de peche commerciale. Nous pouvons mesurer le taux de mortalite et les variables demographiques, en parti- culier l'âge et la taille a la maturite, en laboratoire et en nature. Nous avons manipule les taux de mortalite en nature et mesure le taux d'evolution. Une forte mortalite entraine la selection d'une maturite a une taille reduite comme on l'observe dans les peches commerciales, en accord avec la theorie. De plus, la nature et l'importance de la mortalite induite par les predateurs sont comparables a celles causees par la peche commerciale. Le taux d'evolution observe chez les guppys permet de predire une evolution semblable dans les peches commerciales sur une echelle de decennies. Ces caracteristiques appuient les arguments qui veulent que les humains, tout comme les predateurs, aient agi comme agents de selection naturelle en exploitant les populations de poissons. (Traduit par la Redaction) Reznick and Ghalambor 801
Pollen Representation of Vegetation in Quaternary Sediments: Theory and Method in Patchy Vegetation

1 According to the Prentice-Sugita model, pollen loading (PL) is linearly related to the distance-weighted plant abundance (DWPA) surrounding a sedimentary basin. Since source trees of pollen far away from a basin have much less influence on pollen representation than source trees near a basin, the correlation between PL and D WPA should approach an asymptote as the vegetation sampling area increases. The 'relevant source area' for pollen can be defined as the area beyond which the correlation does not improve. 2 A simulation experiment using patchy vegetation landscapes illustrates this principle, demonstrating that r2 and likelihood function scores do not improve when vegetation sampling increases beyond certain distances. This suggests that very little additional information on the pollen-plant abundance relationship will be gained by a vegetation survey beyond the 'relevant' distance when data are collected from regions of similar vegetation type and spatial pattern. 3 The 'relevant' source area for pollen in lakes in the simulated landscapes is within 50-100 m from the lake edge for forest hollows (radius of hollow R = 2 m), 300400 m for small lakes (R = 50 m), and 600-800 m for medium size lakes (R = 250 m). Although only about 30-45% of total pollen loading comes from within these distances, the model demonstrates that when the background pollen is consistent, this proportion is adequate to reflect local vegetation composition. 4 The simulation results show that pollen data from large lakes (R = 750 m) show little site-to-site variation, especially for a species that grows in small patches (radii of 80 m in the simulated landscape). Linear regression and maximum likelihood methods therefore do not provide accurate estimations of pollen productivity and background pollen loading. Vegetation may appear homogeneous even when the actual pattern of vegetation is heterogeneous and patchy, depending on the size of lake relative to the size of patches. 5 The pollen-plant abundance data should be collected from regions with similar forest composition to determine the 'relevant' source area and the parameters of a linear relationship between PL and D WPA. Otherwise, either the linear regression or maximum likelihood methods provide inaccurate estimates of the relevant source area and parameters even when the simulation data with no sampling and counting errors are used.
Nitrogen Isotope Distribution as a Presumptive Indicator of Nitrogen Fixation

The generally lower 15N/14N ratio of nitrogen-fixing organisms provides an opportunity to screen mixed populations for individuals fixing nitrogen. Samplings of associated California native species, along with the soil on which they were found, show differences in 15N/14N ratios suggesting a capability among some for the fixation of nitrogen. Not all suspected fixers were depleted in 15N, and two saprophytes had significant 15N enrichment. The method shows some promise, but further understanding of fractionation processes is needed before the method can be generally applied.
Gravitação modificada pelos efeitos quânticos e as soluções inomogêneas do tipo Kasner.

Nesta dissertacao serao vistos elementos de teoria de gravitacao modificada pelos efeitos quânticos e uma proposta de metrica inomogenea do tipo Kasner. Primeiramente, ira se abordar a teoria semiclassica, consistindo esta na quantizacao dos campos de materia, deixando o campo gravitacional como um campo externo classico. Depois sera vista a acao efetiva induzida pela anomalia como consequencia do traco do tensor-momento energia nao ser nulo a nivel quântico. Por fim, sera considerada a proposta da solucao inomogenea do tipo Kasner e perspectivas futuras para essa solucao.
Ant attendance in aphids: why different degrees of myrmecophily?

1. Aphids show a range of associations with ants from nonattendance to obligate myrmecophily. Aphis fabae cirsiiacanthoides is facultatively associated with ants, while Symydobius oblongus is an obligate myrmecophile. The selection pressures that have shaped these associations are unknown.