Miracle-dz/UniFAR-FTUs huggingface dataset:
Life-History Evolution in Guppies (Poecilia reticulata: Poeciliidae). IV. Parallelism in Life-History Phenotypes

In earlier publications, we reported an association between the life-history patterns of guppies and the types of predators with which they co-occur. We contrasted guppies from high-predation sites (Crenicichla localities) with those from low-predation sites (Rivulus localities) found on the south slope of the Northern Range Mountains of Trinidad. Guppies from high-predation localities attain maturity at an earlier age and smaller size, produce more and smaller offspring per litter, and have higher reproductive allotments than their counterparts from low-predation sites. Here we present a parallel series of analyses for guppies from a new series of localities on the north slope of the Northern Range. These fish are also found in what appear to be high- and low-predation communities, but, with one exception, the species of predators are entirely different from those on the south slope. The larger predators are derived from marine families (gobies and mullets) that have invaded freshwater rivers; the south slope fauna is derived from families typical of mainland South America. If predator-induced mortality selects for life-history evolution, then guppies from high- and low-predation sites on the north slope should have life histories similar to their counterparts on the south slope. We compare the life-history phenotypes of guppies from the north slope communities and find that the high- and low-predation contrasts are remarkably similar to those reported earlier for the south slope communities. We reinforce this comparison with multivariate analyses that use discriminant functions derived for the south slope collections to classify north slope samples. Finally, we exploit recent molecular genetic data and the geographical distribution of high- and low-predation communities to argue for the independent origin of these life-history patterns in each drainage.
Upon Polyembryony and Its Morphology in Opuntia vulgaris

MANY cases of polyembryony are now known, occurring in widely separated groups. Braun, in his summary of the subject in i86o, recorded twenty-one cases in twelve families and thirteen genera, which number has been added to by others. Strasburger was the first to thoroughly investigate its morphological basis, and since his paper in i878 important contributions have been made to the subject by several investigators, notably Dodel (1890), Overton (i89i), Tretjakow (i895), Jeffrey (i895), and Hegelmaier (i897). The results of these works, in so far as they touch this subject, will be found summarized below. In the Cactace2e, the only case of polyembryony hitherto known has been that of Opuntia tortispina, which Engelmann, in his Cactacex of Whipple's expedition figured (p1. 23,fig. 4) as having two embryos in one seed. This case was cited by Braun (p. 155, p1. 5, figs. 18-20), who also suggests that the four cotyledons which he had himself noticed in Opuntia glaucophylla may indicate a fusion of two embryos and hence polyembryony, though he points out that it may also be explained as fasciation. While studying the seedling stages in this family, I have found that Opunha vulgaris is markedly polyenmbryonic, and I may here add that although 1 have worked
The effect of different levels of organic selenium on broiler slaughter traits.

The effect of different levels of organic selenium (selenized yeast) on slaughter meat traits of fattening chickens (broilers) was investigated. Trial was carried out on 120 Hybro-PN chickens divided into four groups, in duration of six weeks. All groups of chickens were fed complete mixtures, and selenium was added to the food in the form of selenized yeast in the amount of 0 (I ); 0,3 (II); 0,6 (III) or 0,9mg/kg (IV-group). The highest average values of carcass yield 'conventional processing', 'ready to roast' and 'ready to grill' were recorded in chickens of group III (2059,6, 1851,97 and 1756,45g), with addition of 0,6mg Se/kg, followed by chickens of group II (2048,17, 1841,36 and 1748,57g) and group IV (1957,46, 1764,22 and 1676,05g) with 0,3 and 0,9mg/kg of added selenium, respectively, whereas the lowest values (1835,21, 1660,87 and 1572,61g) were established in chickens of group I without addition of this micro element. Average values of slaughter yields 'conventional processing', 'ready to roast' and 'ready to grill' were approximately the same in chickens of all investigated groups, and established differences showed no statistical significance (P > 0,05). The lowest breast mass was in I group (573,55g), and the highest in group III (657g). Chickens of groups II and IV (with 0,3 and 0,9mg Se/kg of feed) realized breast mass of 627,90 and 633,12g. Compared to group I, average breast mass of chickens in groups III and IV was considerably higher (P < 0,05 and P < 0,01). Share of breast in the mass of processed carcass was the highest in groups III and IV (37,40 and 37,86%), and the lowest in group II (36,0%). In chickens of group I the stated value was 36,47%. Average share of thighs in the mass of processed carcass was approximately the same in all investigated groups. The highest value (14,4%) was established in chickens of group II, and the lowest (13,98%), in chickens of III investigation group. Chickens fed organic selenium in diet (0,3, 0,6 and 0,9mg/kg) had by 3,80, 3,74 and 3,18% higher share of drumsticks in the mass of processed carcass compared to group I.
O desafio do desenvolvimento local sustentável na era da gestão das competências

Globalization has been done under the auspices of a combination of several factors. Among these we highlight the trade liberalizations, the creation of an international financial market, the new technologies of information and communication and also a political action coordinated by the major economies (G8 and G20). Nevertheless, in the eyes of the public opinion, this coordination does not result in a substantial decrease of social injustice and a better control of the 4 big crises: economic, financially, social and ecological. The path of global 1 Professor Catedrático, do Instituto Superior de Ciências Sociais e Políticas da Universidade de Lisboa. Email: alopes@iscsp.ulisboa. pt
Regulation of the Na+/H+ exchanger in the healthy and diseased myocardium

Background: Na+/H+ exchangers (NHE's) are membrane proteins that regulate ion fluxes, they extrude one intracellular proton in exchange for one extracellular sodium thereby regulating intracellular pH. Mammalian NHE's have nine isoforms, NHE1–NHE9. NHE1 is present in all mammalian cell and is the only isoform present in cardiomyocytes. NHE1 contributes to damage to the myocardium with ischemia and reperfusion and to heart hypertrophy. Objective: To summarize the current state of knowledge with regard to regulation of NHE1 in the myocardium. Methods: A review of relevant literature. Results: Inhibition of NHE reduces ischemia–reperfusion damage and development of hypertrophy. Extracellular-signal-regulated kinase (ERK)-dependent phosphorylation activates NHE1 in the myocardium. Ischemia and subsequent reperfusion activates the ERK-dependent pathway and may lead to aggravation of damage. Conclusions: Elucidation of the regulatory pathway of NHE1 in the myocardium could lead to novel approaches to reduce heart hypertrophy and ischemia–reperfusion damage.
Adverse effects of chromium on amino acid levels in freshwater fish Clarias batrachus (Linn.)

Various heavy metals released into the rivers and lakes affect aquatic fauna including Clarias batrachus. Elevated levels of chromium (Cr) in aquatic organisms, especially fish, represent an ecological and human concern. Amino acid levels were estimated in five tissues (gills, liver, kidneys, muscle, and brain) of C. batrachus after 28 days of exposure to Cr. This study showed that Cr elevated levels of free amino acids in organs of fish C. batrachus, indicating a compensatory mechanism to counter sublethal metallic stress. Data suggest that the measurement of amino acids may serve as a biomarker for Cr toxicity in fish.
Calcium Channel β Subunits Differentially Regulate the Inhibition of N-type Channels by Individual Gβ Isoforms*

The direct inhibition of N- and P/Q-type calcium channels by G protein βγ subunits is considered a key mechanism for regulating presynaptic calcium levels. We have recently reported that a number of features associated with this G protein inhibition are dependent on the G protein β subunit isoform (Arnot, M. I., Stotz, S. C., Jarvis, S. E., Zamponi, G. W. (2000) J. Physiol. (Lond.) 527, 203–212; Cooper, C. B. , Arnot, M. I. , Feng, Z. -P., Jarvis, S. E. , Hamid, J., Zamponi, G. W. (2000) J. Biol. Chem. 275, 40777–40781). Here, we have examined the abilities of different types of ancillary calcium channel β subunits to modulate the inhibition of α1B N-type calcium channels by the five known different Gβ subunit subtypes. Our data reveal that the degree of inhibition by a particular Gβ subunit is strongly dependent on the specific calcium channel β subunit, with N-type channels containing the β4 subunit being less susceptible to Gβγ-induced inhibition. The calcium channel β2asubunit uniquely slows the kinetics of recovery from G protein inhibition, in addition to mediating a dramatic enhancement of the G protein-induced kinetic slowing. For Gβ3-mediated inhibition, the latter effect is reduced following site-directed mutagenesis of two palmitoylation sites in the β2aN-terminal region, suggesting that the unique membrane tethering of this subunit serves to modulate G protein inhibition of N-type calcium channels. Taken together, our data suggest that the nature of the calcium channel β subunit present is an important determinant of G protein inhibition of N-type channels, thereby providing a possible mechanism by which the cellular/subcellular expression pattern of the four calcium channel β subunits may regulate the G protein sensitivity of N-type channels expressed at different loci throughout the brain and possibly within a neuron.
Establishment of hemiparasitic Rhinanthus spp. in grassland restoration: lessons learned from sowing experiments

Questions What are the factors limiting the establishment of hemiparasitic Rhinanthus spp. , ecosystem engineers promoting diversity and stability of communities, in restoration of species-rich meadows? How can these constraints be overcome? Location Czech Republic, Central Europe. Methods Sowing of Rhinanthus seeds in grasslands of different history, biotic and abiotic properties accompanied by a variety of management practices. Followed by consequent monitoring of establishment and population dynamics and synthesis of relevant literature resources. Results Appropriate timing of seed sowing is needed for successful Rhinanthus introduction. Rhinanthus seeds must be sown at latest in November to break their dormancy (valid for Central European populations; might be different e.g. in oceanic regions). Rhinanthus is able to establish a viable population mainly in low- to moderately-productive grasslands with biomass production below 500 g·DW·m−2. Its establishment is difficult in grasslands of higher productivity due to the effect of competition for light on the seedlings. Rhinanthus requires grasslands with appropriate management including mowing and removal of litter, if it accumulates. Otherwise, the litter layer strongly suppresses seedling establishment. Litter removal can allow establishment even in some productive communities such as stands of Calamagrostis epigejos. However, early mowing (i.e. mowing conducted before ripening of seeds) can lead to a strong decline or even local eradication of the hemiparasitic annuals. Soil conditions on the site of seed origin and the target site can play an important role, as indicated by failures of establishment of Rhinanthus originating from slightly acidic soils on sites with soil pH values around 8. Suitability of a given site for Rhinanthus introduction can be estimated on the basis of its species composition using the Beals index or less formal expert knowledge of local floristic associations of Rhinanthus spp. In the case of suitable conditions, sowing density of 200–500 seeds·m−2 should be sufficient for Rhinanthus establishment. Conclusion Mowing or grazing, litter removal, proper timing of sowing, and use of the seeds from local seed sources should considerably increase probability of Rhinanthus successful introduction. However, stochastic events like adverse weather conditions or damage through herbivory make the prediction of introduction success difficult.
Calanus glacialis and Calanus marshallae response to an upcoming climate change in the Arctic and Bering Sea

One of the multiple consequences of global warming is the loss of sea ice cover of the Arctic and warming up of its surface waters. It is predicted that in 35 years the Arctic will be ice free in summer. It has to be considered that these changes in the environment will have irreversible consequences for marine ecosystems. Some of the consequences that are being most considered are the increase in primary productivity and the potential mismatch between the primary and secondary production. In this review I have studied the phenology and life cycle of two species of common Arctic copepods of the genus Calanus (C. gracialis and C. marshallae) along the Bering, Chukchi and Beaufort seas in the context of the above mentioned aspects of climate. I concluded that the most likely scenario is that primary productivity will increase and, with the exception of the Bering Sea, secondary productivity will increase as well. In addition, the successful colonization of C. marshallae in the Arctic Ocean likely results from the increase in primary productivity, temperature and longer growing season.
Chromatin Remodeling in Carcinoma Cells

Carcinoma arises from the malignant transformation of epithelial cells, which involves the deregulation of genetic information leading to excessive proliferation, cell death evasion, and invasive potential. The traditional dogma was that the underlying genetic deregulation emerged through an accumulation of individual mutations that inactivate tumor suppressor genes and activate oncogenes. During recent years, it has become evident that epigenetic changes are potently contributing to tumor formation. Epigenetics describes the modulation of genetic information by mechanisms other than sequence alterations of the underlying DNA. A major part of epigenetic gene regulation is accomplished through chromatin remodeling. In eukaryotic cells, huge amounts of DNA are managed through intricate mechanisms that allow DNA condensation into tightly packable protein–DNA units (chromatin), and chromatin-remodeling processes render DNA either accessible or inaccessible to diverse DNA processes such as replication and transcription. The role of chromatin remodeling in carcinoma cells is reviewed in this chapter. Keywords: Chromatin; Histone modification; ATP-dependent chromatin remodeling; SWI/SNF; Carcinoma; Tumor suppressor; Senescence
Genetics of tan necrosis and extensive chlorosis in tan spot of wheat caused by Pyrenophora tritici-repentis.

Pyrenophora tritici-repentis (Ptr) induces tan necrosis and/or chlorosis, including extensive chlorosis in differential wheat cultivars. Reciprocal crosses were made in all combinations between the hexaploid wheats Glenlea (necrotic only), 6B365 (chlorotic only), and Salamouni (non-necrotic, nonchlorotic). F 1 , F 2 , and F 3 progenies were sequentially tested for extensive chlorosis by using isolate D308 (nec - chl + ) and for tan necrosis with isolate 86-124 (nec + chl - ) and/or the Ptr necrosis toxin (.)
Scale and species richness: towards a general, hierarchical theory of species diversity

Current weaknesses of diversity theory include: a failure to distinguish different biogeographical response variables under the general heading of diversity; and a general failure of ecological theory to deal adequately with geographical scale. Our aim is to articulate the case for a top‐down approach to theory building, in which scale is addressed explicitly and in which different response variables are clearly distinguished.
Proteinase Production and Pathogenicity of Candida albicans

In order to investigate a role of proteinase in the pathogenesis of Candida infections, invasion of C. albicans strains of different proteinase activity into the chorioallantoic membrane (CAM) of developing chicks was studied. Eight strains were used after examining the inducible proteinase activity in the culture containing bovine serum albumin as the sole source of nitrogen. Six were proteinase‐producing strains (type I) and two were proteinase‐deficient ones (type II). Type I strains were subdivided into type Ia strains in which the proteinase activity persisted for a week in the in vitro culture and type Ib ones in which the enzyme activity was lost by the 7th day after inoculation. By inoculation onto CAM, the type I strains could invade the tissue in which secreted proteinase was detected on the periphery of the invading Candida cells by immunohistochemical method. At an early stage of the infection, proteinase secretion was detected on the surface of the yeast cells before their entry into the tissue. The type II strains remained on the surface of the CAM and did not invade the tissue where the secretion of the enzyme was not detected. The mortality rate of the chick embryo was not correlated with the degree of proteinase production of these strains. Two type Ib strains invaded the CAM tissue and elicited some tissue reactions by the host, yielding a low mortality rate of the chick embryos. These results suggested that the secretion of proteinase was an important factor for the invasion of CAM but other factors were also involved for the pathogenicity of C. albicans.
Control of Blood Flow to Cardiac and Skeletal Muscle During Exercise

The sections in this article are: 1 Hemodynamics and Control of Blood Flow 1.1 Determinants of Vascular Resistance 1.2 Central Vascular Control Mechanisms 1.3 Local Vascular Control Mechanisms 2 Coronary Vascular Response to Exercise 2.1 Effect of Exercise on Left Ventricular Blood Flow 2.2 Right Ventricular Blood Flow during Exercise 2.3 Mechanisms Of Coronary Vasodilation during Exercise 2.4 Autonomic Nervous System Influences 2.5 Extravascular Determinants of Coronary Blood Flow 2.6 Epicardial Coronary Arteries 3 Effects of Physical Conditioning on the Coronary Circulation 3.1 Structural Adaptations 3.2 Adaptations of Neurohumoral Control 3.3 Local Coronary Vascular Control 3.4 Integrated Coronary Vascular Adaptations 3.5 Extravascular Determinants of Coronary Blood Flow 4 Skeletal Muscle Blood Flow During Exercise 4.1 Skeletal Muscle Blood Flow during Isometric Contraction 4.2 Skeletal Muscle Exercise Hyperemia 4.3 Regional Distribution of Skeletal Muscle Blood Flow 4.4 Mechanisms of Exercise Hyperemia 4.5 Regulation of Transcapillary Fluid and Solute Exchange in Skeletal Muscle 4.6 Regulation of Tissue Oxygenation in Exercising Skeletal Muscles 4.7 Determinants of Skeletal Muscle Arteriovenous Oxygen Difference 5 Effects of Physical Conditioning on Skeletal Muscle Vascular Beds 5.1 Skeletal Muscle Blood Flow Capacity 5.2 Skeletal Muscle Capillary Diffusion Capacity 5.3 Structural Vascular Adaptation 5.4 Adaptations of Vascular Control 6 Conclusion
Secretion of IL-2 and IFN-γ, But Not IL-4, by Antigen-Specific T Cells Requires Extracellular ATP1

Extracellular ATP and other nucleotides transmit signals to cells via surface-associated molecules whose binding sites face the extracellular milieu. Ecto-nucleoside triphosphate diphosphohydrolase is such an ATP-binding enzyme that is expressed by activated lymphocytes. We have previously shown that nonhydrolyzable ATP analogs block the lytic activity of NK cells and CD8+ T cells as well as their E-NTPDase activity. These results suggest that the hydrolysis of ATP may play a role in lymphocyte function. Here we report that E-NTPDase activity is up-regulated within 15 min of T cell stimulation and that reversible and irreversible enzyme inhibitors profoundly reduce secretion of IL-2 and IFN-γ, but not IL-4. TNF-α, IL-10, and IL-5 production showed intermediate sensitivity to these ATP analogs. Depletion of extracellular ATP also inhibited secretion of IFN-γ, but not IL-4, supporting the interpretation that extracellular ATP is required for secretion of some, but not all, cytokines. E-NTPDase antagonists reduced transcription of IL-2 mRNA and inhibited TCR-mediated intracellular calcium flux. These results suggest that extracellular ATP plays an essential role in the TCR-mediated signal transduction cascade for expression of certain cytokine genes.
Effects of soil fertility on growth, tuber yield, nodulation and nitrogen fixation of yam bean (Pachyrhizus erosus (L.) urban) grown on a typic eutrustox

Abstract The tuberous legume, Yam Bean, (Pachyrhizus erosus (L.) Urban, has been utilized as a food crop for many centuries. The large, starchy tubers have higher aitrogen content than potatoes, cassava and taro roots with 20% or more of the N fraction as ureidoglyco‐lates. Yam Bean (Jicama) tuber growth within the neotropical regions of the world is influenced by soil productivity. The objective of this study was to determine effects of soil fertility treatments on tuber yield, nodulation characteristics and nitrogen fixation. Highly significant increases in growth and tuber production resulted with P additions, and to Ca and K levels when combined with P. Nodule weight and nitrogenase activity were similar in response to factorial soil treatments as were the tuber and total above ground plant growth. Total ureide content of tuber epiperi‐derm tissue increased significantly with P, Ca, and P + Ca treatments and increased quadratically with increased K additions when combined with P, Ca, and P + Ca treatm.
Environmental influence and cohort effects in a sexual ornament in the house sparrow, Passer domesticus

Presence of phenotypic variation is necessary for selection to occur, yet processes affecting variation in sexually selected characters in natural populations are poorly understood. Here we examine whether variation in a sexual ornament (badge size) of male house sparrows (Passer domesticus) is dependent on individual variation in the conditions during early ontogenetic stages, and whether this variation and the population-wide effects of external variables such as weather or population size jointly will generate consistent differences among cohorts later in life. Variation in badge size was independent of adult body size, whereas heavier fledglings and fledglings in good body condition developed smaller visible badges as adults. Furthermore, strong cohort-effects were present, caused by a combined effect of density-dependence and weather during the early development in the moulting period and autumn after hatching. Thus, badge size is an environmentally-dependent trait in house sparrows, and likely to be under the influence of both natural and sexual selection.