Miracle-dz/UniFAR-FTUs huggingface dataset:
Sex differences in the trade-off between feeding and mating in the guppy

Male guppies Poecilia reticulata court almost continuously and often indulge in sneaky mating attempts. Female guppies, on the other hand, devote much of their time to foraging. This paper demonstrates that both sexes reduce their feeding rate in mixed-sex groups relative to single sex ones and suggests that the decrease is less pronounced for females than for males. Thus males make feeding and mating decisions that are dependent on hunger while female foraging behaviour is constrained by sexual harassment. The observed sex differences in behaviour are a consequence of asymmetrical mating costs in males and females.
Factors affecting freezing tolerance: a comparative transcriptomics study between field and artificial cold acclimations in overwintering evergreens.

Cold acclimation (CA) is a well-known strategy employed by plants to enhance freezing tolerance in winter. Global warming could disturb CA and increase the potential for winter freeze-injury. Thus, developing robust freezing tolerance through complete CA is essential. To explore the molecular mechanisms of CA in woody perennials, we compared field and artificial CAs. Transcriptomic data showed that photosynthesis/photoprotection, and fatty acid metabolism pathways were specifically enriched in field CA; carbohydrate metabolism, secondary metabolism, and circadian rhythm pathways were commonly enriched in both field and artificial CAs. When compared with plants in vegetative growth in the chamber, we found that the light signals with warm air temperatures in fall might induce the accumulation of leaf abscisic acid (ABA) and jasmonic acid (JA) concentrations, and activate Ca2+ , ABA, and JA signaling transductions in plants. With the gradual cooling occurrence in winter, more accumulation of anthocyanin, chlorophylls degradation, closure/degradation of photosystem II reaction centers, and substantial accumulation of glucose and fructose contributed to obtaining robust freezing tolerance during field CA. Moreover, we observed that in Rhododendron 'Elsie Lee', ABA and JA decreased in winter, which may be due to the strong requirement of zeaxanthin for rapid thermal dissipation and unsaturated fatty acids for membrane fluidity. Taken together, our results indicate that artificial CA has limitations to understand the field CA, and field light signals (like short photoperiod, light intensity, and/or light quality) before the low temperature in fall might be essential for complete CA.
A study on the structure, mechanism, and biochemistry of kanamycin B dioxygenase (KanJ)—an enzyme with a broad range of substrates

Kanamycin A is an aminoglycoside antibiotic isolated from Streptomyces kanamyceticus and used against a wide spectrum of bacteria, including Mycobacterium tuberculosis. Biosynthesis of kanamycin involves an oxidative deamination step catalyzed by kanamycin B dioxygenase (KanJ), thereby the C2’ position of kanamycin B is transformed into a keto group upon release of ammonia. Here, we present for the first time, structural models of KanJ with several ligands, which along with the results of ITC binding assays and HPLC activity tests explain substrate specificity of the enzyme. The large size of the binding pocket suggests that KanJ can accept a broad range of substrates, which was confirmed by activity tests. Specificity of the enzyme with respect to its substrate is determined by the hydrogen bond interactions between the methylamino group of the antibiotic and highly conserved Asp134 and Cys150 as well as between hydroxyl groups of the substrate and Asn120 and Gln80. Upon antibiotic binding, the C terminus loop is significantly rearranged and Gln80 and Asn120, which are directly involved in substrate recognition, change their conformations. Based on reaction energy profiles obtained by density functional theory (DFT) simulations, we propose a mechanism of ketone formation involving the reactive FeIV = O and proceeding either via OH rebound, which yields a hemiaminal intermediate or by abstraction of two hydrogen atoms, which leads to an imine species. At acidic pH, the latter involves a lower barrier than the OH rebound, whereas at basic pH, the barrier leading to an imine vanishes completely.
Evaluation of Antimutagenic Effect of Flavonoid of Kigelia Africana on Swiss-Albino Mice

The present study was designed to evaluate the antimutagenic potential of flavonoid of Kigelia africana leaves, using micronucleus and chromosomal aberration assay in mouse bone marrow. The antimutagenic effect of flavonoid of Kigelia africana leaves was assessed using cyclophosphamide induced micronuclei (MN) formation and chromosomal aberration (CA) in mouse. The animals were pre-treated with the flavonoid of Kigelia africana given orally (p.o.) at two test doses of 100 & 200 mg/kg body weight for 7 days. In MN test the two doses provided protection when given 24 h prior to a single i.p. administration of 100mg /kg body weight of cyclophosphamide and the efficacy of the test doses were compared with the control group. In CA assay the two doses provided protection when given 24 hours prior to a single ip administration (100mg/kg body weight) of cyclophosphamide followed by a single ip administration of colchicine (4mg/kg body weight), 90 minutes before cell harvesting and efficacy of the test doses were compared with that of the control group. The percentage protection was increased in a dose dependent manner. These results demonstrate that flavonoid of Kigelia africana has got antimutagenic potential.
Mineral nitrogen affects nodulation and amino acid xylem transport in the Amazonian legume Inga edulis Mart

The characteristics of symbiotic nitrogen fixation in tropical forest tree species have received little attention but it is well established that mineral N negatively affects symbioses in crop legumes such as soybean and common bean. Nevertheless, ecophysiological mineral nitrogen dynamics in terms of nitrogen xylem transport of native Amazonian legume has been not documented so far.The objective of this study was to evaluate nodulation and amino acid xylem transport of Inga edulis, a tropical Amazonian perennial legume, in response to mineral N. Plant growth, nodule number, nodule dry weight and xylem sap amino acid contents were determined in nodulated I. edulis in response to nutrition with ammonium, nitrate or no mineral N (total dependence on N2fixation). In addition, free individual amino acids were quantified in the different plant tissues and in the xylem. Plant growth (total dry weight) responded significantly to both nitrate and ammonium, especially the latter. Nitrate negatively affected nodulation and total amino acid transport to the shoot while ammonium increased nodule dry weight, but not total amino acid contents of the xylem which diminished. On the other hand, mineral-N showed only discrete changes in the amino acid composition of the xylem where asparagine was the predominant form. Our results suggest that I. edulis responds to ammonium nutrition through greater plant and nodule growth compared to the other N sources, consistent with ammonium being the principal source of mineral N in the acid soils of the natural habitat of this species. Key words: Tropical tree species, nitrogen fixation, glutamine, symbiosis.
Proceedings of The Thoracic Society

J. M. KAY The phenomenon of hypoxic pulmonary hypertension in man living at high altitude was first described by Rotta et al. (1956) in Peru who found that the mean pulmonary artery pressure in seven residents of Morococha (4540 m) was 25 mmHg compared with a value of 12 mmHg in residents of Lima (152 m). A regression equation has been devised for predicting pulmonary artery pressure at various altitudes in Latin America but there is great individual variation in the pressure found in different subjects living at the same altitude. The pulmonary artery pressure in residents of Leadville, Colorado (3110 m) is higher than predicted on the basis of Latin American experience and exceeds the pressure found at 3720 m in Peru. This is probably related to the fact that the Leadville community was established only 100 years ago, and very few families have lived there for more than two generations, whereas the Indian population of the Andes has lived at high altitude over the past 9000 years. People and animals living at high altitude have right ventricular hypertrophy and an abnormal muscularization of their pulmonary arterioles when compared with their sea level counterparts. Chronic hypoxic pulmonary hypertension and the associated pulmonary vascular changes are reversible (Abraham et al., 1971). When high altitude residents descend to sea level, the electrocardiographic signs of right ventricular hypertrophy and the pulmonary hypertension regress after several months. Pulmonary hypertension develops in animals exposed to high altitude but there is considerable species variation. Cattle are particularly susceptible and may develop right heart failure ('brisket disease') if grazed at altitudes over 2130 m. The mechanism whereby alveolar hypoxia produces pulmonary vasoconstriction remains elusive. It is a local phenomenon since it occurs in isolated perfused lungs. Alveolar hypoxia may cause the release of a vasoconstrictor substance from a site in the lung parenchyma close to small pulmonary arteries (Kay et al., 1974).
HABITAT RELATIONSHIPS OF BIRDS OVERWINTERING IN A MANAGED COASTAL PRAIRIE

Abstract Grassland birds are considered to be rapidly declining in North America. Management approaches for grassland birds frequently rely on prescribed burning to maintain habitat in suitable condition. We evaluated the relationships among years since burn, vegetation structure, and overwintering grassland bird abundance in coastal prairie. Le Conte's Sparrows (Ammodramus leconteii) were most common in areas that had: (1) been burned within the previous 2 years, (2) medium density herbaceous vegetation, and (3) sparse shrub densities. Savannah Sparrows (Passerculus sandwichensis) were associated with areas: (1) burned within 1 year, (2) with sparse herbaceous vegetation, and (3) with sparse shrub densities. Sedge Wrens (Cistothorus platensis) were most common in areas that had: (1) burned greater than 2 years prior and (2) dense herbaceous vegetation. Swamp Sparrows (Melospiza georgiana): (1) were most common in areas of dense shrubs, (2) not related to time since burnings, and (3) demonstrated no relationship to herbaceous vegetation densities. The relationships to fire histories for all four bird species could be explained by the associated vegetation characteristics indicating the need for a mosaic of burn rotations and modest levels of woody vegetation.
Developmental Changes in Endogenous Abscisic Acid Concentrations and Asymbiotic Seed Germination of a Terrestrial Orchid, Calanthe tricarinata Lindl.

Changes in endogenous abscisic acid (ABA) concentrations were investigated in developing seeds and the pretreated seeds ofCalanthe tricarinata, a hard-to-germinate terrestrial orchid. ABA concentration was as low as 2.16 to 2.26 ngmg -1 fresh weight at the proembryo stage (60 to 90 days after pollination (DAP)) and then continuously increasedto11.6ngmg -1 freshweightat210DAP.Seedmaturationwasaccompaniedbyadramaticdecrease inwater content and a prominent accumulation of protein and lipid bodies within the embryo proper. The optimum time for asymbioticseedgermination wasobtainedfromimmatureseeds at150DAP.Atthisstage,the embryoproperreached its maximum size, and the seedcoat became dehydrated and gradually shrunk into a thin layer. By 180 DAP, seed germination declined sharply as seed approached maturity. Mature seeds pretreated with ultrasound (45 min), 1% NaOCl (45 to 60 min), or 1N NaOH (45 min) were effective in improving the germination percentage and lowering seed ABA concentrations. Our results suggest that high concentrations of endogenous ABA in orchid seeds may play a critical role in arresting embryo growth and in preventing seed germination.
Deposição de sílica e teor de nitrogênio e silício em arroz

A adubacao nitrogenada e pratica importante para alcancar altas produtividades, entretanto doses elevadas de nitrogenio podem causar tombamento e tornar as plantas mais suscetiveis a doencas. Numerosos estudos tem demonstrado que muitas gramineas acumulam silicio em seus tecidos, e que a maior parte deste elemento e depositado na folha, o que funcionaria como uma barreira mecânica a entrada de doencas. Entretanto elevadas doses de nitrogenio podem diminuir a deposicao de silica nas plantas. O objetivo deste trabalho foi avaliar o teor de nitrogenio e silicio na parte aerea, e a deposicao de silica em folhas de plantas de arroz de terras altas em funcao das doses de Si e N. O delineamento experimental utilizado foi inteiramente casualizado, em esquema fatorial 3 x 2, com cinco repeticoes. Os tratamentos foram constituidos por tres doses de N (5, 75 e 150 mg dm-3 de N) tendo como fonte a ureia e duas doses de Si (0 e 400 mg dm-3 de SiO2) tendo como fonte o silicato de calcio (Wollastonita) . O incremento da adubacao com ureia reduziu o teor de Si na planta de arroz e a deposicao de silica na parede externa das celulas da epiderme das folhas de arroz.
Effects of dietary Saccharomyces cerevisiae and butyric acid glycerides on performance and serum lipid level of broiler chickens.

Summary This experiment was conducted to evaluate the effects of dietary supplementation of live yeast Saccharomyces cerevisiae (SC) and butyric acid glycerides (BAG) on broiler performance and serum lipid composition. One-day-old ROSS 308 female chicks (n=378) were randomly distributed in a 3×3 factorial arrangement with three replicates for each increasing levels of (0, 0.002, and 0.004 g/g) BAG and (0, 0.003, and 0.006 g/g) SC respectively. The experiment lasted 42 d, consisting of starter (1-21 d) and grower (22-42 d) periods. Body weight (BW), feed intake (FI), and feed conversion ratio (FCR) were determined by the period for each treatment. On d 42, serum concentrations of triglycerides, cholesterol, and HDL were determined. Saccharomyces cerevisiae had no effect on performance in the starter period. However, chicks fed 0, 0.002, and 0.004 g/g BAG had higher BW and better FCR than control diet (P<0.05). In the grower period BW of chicks fed 0.006 g/g SC was higher than other treatments (P<0.05). For BAG both levels improved (P<0.05) BW and FCR. In serum composition, both BAG and SC decreased cholesterol concentrations (P<0.05), but the HDL levels were higher (P<0.05) only in 0.006g/g SC fed chicks. There were no significant effects in triglyceride levels among treatments. There were no SC and BAG interaction effect on response variables. In conclusion, dietary BAG improves growth performance in starter and grower periods but SC was only effective in grower period. Moreover, both BAG and SC had positive effect on serum lipid composition.
Controlled Drought Affects Morphology and Anatomy of Salvia splendens

Polyethylene glycol 8000 (PEG-8000) was applied to a soilless growing medium at the concentrations of 0, 15, 20, 30, 42, or 50 g·L -1 to impose controlled drought. Salvia (Salvia splendens F. Sellow. ex Roem & Shult.) seeds were planted in the growing medium to determine if controlled drought affects morphology and anatomy of salvia. Polyethylene glycol decreased emergence percentage and delayed emergence up to 5 days. Stem elongation of salvia treated with the fi ve lowest concentrations was reduced up to 35% (21 days after seeding), and salvia were a maximum of 53% shorter and the canopy was 20% more narrow compared to nontreated seedlings 70 days after seeding. These morphological changes were attributed to PEG-8000 mediated reduction in leaf water potential (Ψw). The growing medium Ψw ranged from -0.29 to -0.85 MPa in PEG-8000 treated plants, and plant height was positively correlated with Ψw 21 days after seeding. Stem diameter of PEG-treated seedlings was reduced up to 0.4 mm mainly due to reduc- tions in vascular cross-sectional area. Xylem cross-sectional area decreased more than stem and phloem cross-sectional area. Polyethylene glycol 8000 reduced vessel element number, but not diameter. Drought is commonly used to reduce elongation (or growth) of greenhouse ornamentals. Plants grown in substrates that have a low water potential (Ψw) typically have low leaf Ψw and turgor potential (Ψp). Turgor potential, in excess of the minimum "yield" threshold, is the driving force for cell elongation (Carpita and McCann, 2000; Cosgrove, 1997; Frensch, 1997; van Volkenburgh 1999). Thus, commercial greenhouse growers use drought stress to slow elongation of plants such as vegetable transplants (Latimer, 1992; Latimer and Severson, 1997). The disadvantage of using drought to reduce ornamental seed-
Control of Rhizoctonia solani in Soybean (Glycin max L) by seed-coating with Trichoderma viride and Gliocladium virens spores

Objectives: The study evaluated biocontrol of root-rot disease caused by Rhizoctonia solani on soybean using two antagonistic fungal species Trichoderma viride and Gliocladium virens, applied as seed coating or culture filtrate. Methodology and Results: Pathogenic R. solani was added to sterile vermiculite in pots to give an inoculum density of 1- 5 g fresh weight mycelium/kg of sterile vermiculite. Sterilized soybean seeds were treated before planting by soaking for 30 min in 4 x10 6 CFU/ ml spore suspensions of either T. viride or G. virens. Coating soybean seeds with T. viride spores reduced the incidence of root-rot disease by up to 83% in the greenhouse experiment. Coating seeds with G. virens spores also decreased disease incidence but to a lesser extent than T. viride. Cell free culture filtrates of both T. viride and G. virens also significantly inhibited the growth of R. solani , with effect increasing as the concentration of the filtrates in the culture media increased. The root exudates of soybean seedlings increased the growth of the pathogenic fungus. Potential application of findings: The results show that coating soybean seeds with the spore suspension of T. viride or G. virens can effectively control R. solani on soybean.
Fósforo e potássio na sucessão trigo/milho: épocas e formas de aplicação

The increase in adoption of no till management practiced in Southern Brazil is leading farmers to wonder about the advantages of fertilizer application in winter crops to be fed by the subsequent summer crop. Such practice would potentially result in a more flexible seeding schedule and a more efficient use of machinery, work force and fertilizers. This work had the objective of evaluating the anticipation of the phosphorus and potassium application from summer to winter. The experiment was made in 2002 and 2003, in SLC Agricola Ltda at Fazenda Paineira in Coronel Bicaco, RS, in a Hapludox with high levels of phosphorus and potassium. The treatments were composed of the application in the winter crop of the recommended fertilizers for the next summer crop, in the seed line or broadcast distribution. The experiment was arranged in a randomized block design with three blocks and nine treatments. A low response was noticed in grain yield with the phosphorus and potassium application in soil with high levels of these nutrients, indicating that in these conditions the application of recommended fertilizers for summer crop in the winter crop, can be justified by the operation facilities in the system application of fertilizers.
Emergência e desenvolvimento de espécies nativas em área degradada por disposição de resíduos sólidos urbanos

O crescimento acelerado da populacao juntamente com o atual padrao de vida vivenciados nas ultimas decadas vem trazendo diversos impactos ambientais e sociais. Na maioria dos municipios a disposicao de residuos solidos urbanos (RSU) e descartada em areas sem previo tratamento ou fiscalizacao adequada, que quando sao desativadas encontram-se degradadas e necessitam da elaboracao de um plano de recuperacao e revegetacao, alem do monitoramento, ao longo dos anos, para avaliar o desenvolvimento das especies implantadas. Todavia estes problemas podem ser minimizados, principalmente se houver a recuperacao do local atingido. Sendo assim, o presente estudo visou avaliar a emergencia das especies arboreas semeadas na cova e em sulco aos 90 dias, e o desenvolvimento das plântulas emergidas aos 210 e 300 dias, podendo assim avaliar as especies que melhor se adaptam a condicao da area do lixao de Inconfidentes-MG. O experimento foi instalado no delineamento estatistico inteiramente casualizado com 3 tratamentos de semeadura direta, com 15 especies arboreas nativas e tres repeticoes (T1: semeadura direta de especies nativas em cova; T2: semeadura direta de especies nativas em sulco atraves de muvuca; T3: semeadura direta de especies nativas associadas com feijao-guandu em sulco atraves de muvuca). O modelo de plantio que tem a associacao de sementes de especies arboreas com feijao-guandu em sulco (T3) e o metodo mais indicado para a recuperacao de areas de lixoes. As especies arboreas que se destacaram quanto a emergencia e estabelecimento foram Schizolobium parahyba (guapuruvu) e Eritrina speciosa (molungu).
Elucidating the role of Hmx1 during mouse development

This thesis focuses on the study of H6 homeobox 1 (HMX1) gene, a homeobox-containing transcription factor involved in sensory organ and eye development and responsible for the oculo-auricular syndrome of Schorderet-Munier-Franceschetti. The purpose of my study is to better understand the mechanism and role of this transcription factor. My thesis is divided into three parts. The first part proposes a predictive promoter model approach to identify new HMX1 target gene. The second part concerns an animal model of Hmx1 mutation, the dumbo mouse model, and brings a new insight into lethal craniofacial defects. The third part concerns the characterization of the visual capacity of the dumbo mice and a description of a new pattern of vision-linked defects. In the first part we propose a predictive promoter model approach based on transcriptomic analysis of post-natal day 15 mouse retina from dumbo and wild type mouse. This method revealed that Sgcg, Tshz2 and Slc6a9 were Hmx1 targets in the mouse retina. Ptpro, Sema3f, and Epha6 belong to the retinal axon guidance pathway and play an important role in retinotopic mapping. Significant enrichment of HMX1 binding site confirmed this pathway and we validated the transcriptional activity of Hmx1 on Ptpro, Sema3f and Sgcg by Luciferase assay. In the second part of the project we investigate the dumbo mouse model, carrying a stop codon in Hmx1, and representing the first animal model for the oculo-auricular syndrome of Schorderet-Munier-Franceschetti. The homozygous Hmx1dmbo is a semi-lethal mutation and stillborns present severe craniofacial defects, including cleft palate, chest defect and bone hypoplasia of maxilla, zygomatic process, mandible and frontal. In the third part of the thesis we provide a complete description of the vision in dumbo mouse. Despite a normal retinal phenotype, the vision of this mouse is completely impaired. We demonstrate that this was caused by abnormal retinotopic mapping and optic nerve hypoplasia. In dumbo mice the retinal ganglion cells axon projections failed to target the visual output, namely the dorsal lateral geniculate nucleus and the superior colliculus, and present abnormal patterning.