963 resultados para development of suckled young


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Thiamethoxam is a systemic insecticide from the neonicotinoid group, nitroguanidin family which affects the nicotinic receptor acetyl choline in the insect membrane, wounding the nervous system and causing the death of the insect. It was used with success in the control of initial pests of several crops. It was considered that thiamethoxam has a bioactivator effect, because in the absence of insects promoted increase in vigor, development and productivity of crops. This work was carried out to verify if thiamethoxam causes histological changes in sugarcane roots. In this work, it was used optical microscopy, images arrest, tissue biometrics and statistical analysis, in young roots of sugarcane RB 83 5486 after the treatments with different thiamethoxam concentrations. It was determined changes in histological structure of tissues 7, 14, 21 and 28 days after the treatments, establishing its effects on root plant anatomy. It was verified that thiamethoxam increased root cortex width, increasing the vascular cylinder and the metaxylem vessel elements number in the vascular tissue until 21 days after application.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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O setor de floricultura movimenta cerca de um bilhão de dólares no Brasil e o desenvolvimento de técnicas direcionadas ao controle do florescimento é necessário. O presente trabalho avaliou a influência do ácido giberélico (GA3) no desenvolvimento vegetativo e reprodutivo de plantas jovens de Phalaenopsis FSNT 'Dai-Itigo', híbrido de coloração rósea. A aplicação do GA3 foi feita via pulverização foliar nas concentrações de 0, 125, 250, 500 e 1.000 mg L -1. O comprimento das folhas aumentou consideravelmente com o uso do GA3 em baixas concentrações, porém houve diminuição da largura foliar das plantas tratadas com esse fitorregulador. A aplicação do GA3 na concentração de 125 mg L -1 apresentou os melhores resultados para a promoção do florescimento e qualidade da floração deste híbrido de orquídea. Nesse tratamento, aproximadamente 50% das plantas pulverizadas apresentaram floração cerca de 6-12 meses antes da floração das plantas sem aplicação do fitorregulador. em conclusão, a qualidade da floração e das flores foi melhor no tratamento com 125 mg L -1 de GA3.

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Systemic arterial blood pressure and heart rate (f(H)) were measured in unanesthetized, unrestrained larvae and adults of the paradoxical frog, Pseudis paradoxus from São Paulo State in Brazil. Four developmental groups were used, representing the complete transition from aquatic larvae to primarily air-breathing adults. f(H) (49-66 beats/min) was not significantly affected by development, whereas mean arterial blood pressure was strongly affected, being lowest in the stage 37-39 larvae (10 mmHg), intermediate in the stage 44-45 larvae (18 mmHg), and highest in the juveniles and adults (31 and 30 mmHg, respectively). Blood pressure was not significantly correlated with body mass, which was greatest in the youngest larvae and smallest in the juveniles. In the youngest larvae studied (stages 37-39), lung ventilation was infrequent, causing a slight decrease in arterial blood pressure but no change in heart rate. Lung ventilation was more frequent in stages 44-45 larvae and nearly continuous in juveniles and adults floating at the surface. Bradycardia during both forced and voluntary diving was observed in almost every advanced larva, juvenile, and adult but in only one of four young larvae. Developmentally related changes in blood pressure were not complete until metamorphosis, whereas diving bradycardia was present at an earlier stage.

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Hebanthe eriantha (Poir.) Pedersen, a climbing species of the Amaranthaceae increases in stem thickness by forming successive cambia. The family is dominated by herbaceous species and is constantly under discussion due to its disputed nature of the meristem. In the young stem small alternate segments of vascular cambium cease to divide and new arc of cambium initiates outside to it. The newly formed arcs connect with pre-existing alternate segments of cambium to complete the ring. On the contrary, in thick stems, instead of small segments, complete ring of cambium is replaced by new one. These new alternate segments/cambia originate from the parenchyma cells located outside to the phloem produced by previous cambium. Cambium is storied and exclusively composed of fusiform initials while ray cells remain absent at least in the early part of the secondary growth. However, large heterocellular rays are observed in 15-mm diameter stems but their frequency is much lower. In some of the rays, ray cells become meristematic and differentiate into radially arranged xylem and phloem elements. In fully grown plants, stems are composed of several successive rings of secondary xylem alternating with secondary phloem. Secondary xylem is diffuse-porous and composed of vessels, fibres, axial parenchyma while exceptionally large rays are observed only in the outermost regions of thick stems. Vessel diameter increases progressively from the centre towards the periphery of stems. Although the origin of successive cambia and composition of secondary xylem of H. eriantha remains similar to other herbaceous members of Amaranthaceae, the occurrence of relatively wider and thick-walled vessels and large rays in fully grown plants is characteristic to climbing habit. © 2013 Springer-Verlag Wien.

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This study developed a Color Scale of Perceived Exertion (RPE-color scale) and assessed its concurrent and construct validity in adult women. One hundred participants (18-77 years), who were habitual exercisers, associated colors with verbal anchors of the Borg RPE scale (RPE-Borg scale) for RPE-color scale development. For RPE-color scale validation, 12 Young (M = 21.7 yr., SD = 1.5) and 10 Older (M = 60.3 yr., SD = 3.5) adult women performed a maximal graded exercise test on a treadmill and reported perceived exertion in both RPE-color and RPE-Borg scales. In the Young group, the RPE-color scale was significantly associated with heart rate and oxygen consumption, having strong correlations with the RPE-Borg scale. In the Older group, the RPE-color scale was significantly associated with heart rate, having moderate to high correlations with the RPE-Borg scale. The RPE-color scale demonstrated concurrent and construct validity in the Young women, as well as construct validity in Older adults.

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Thiamethoxam is a systemic insecticide from the neonicotinoid group, nitroguanidin family which affects the nicotinic receptor acetyl choline in the insect membrane, wounding the nervous system and causing the death of the insect. It was used with success in the control of initial pests of several crops. It was considered that thiamethoxam has a bioactivator effect, because in the absence of insects promoted increase in vigor, development and productivity of crops. This work was carried out to verify if thiamethoxam causes histological changes in sugarcane roots. In this work, it was used optical microscopy, images arrest, tissue biometrics and statistical analysis, in young roots of sugarcane RB 83 5486 after the treatments with different thiamethoxam concentrations. It was determined changes in histological structure of tissues 7, 14, 21 and 28 days after the treatments, establishing its effects on root plant anatomy. It was verified that thiamethoxam increased root cortex width, increasing the vascular cylinder and the metaxylem vessel elements number in the vascular tissue until 21 days after application.

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Thromboangiitis obliterans (TAO) is a segmental inflammatory occlusive disorder that affects the arm and leg arteries of young smokers. The immune system seems to play a critical role in the aetiology of TAO; however, knowledge of the aspects involved in the progression of vascular tissue inflammation and, consequently, the evolution of this disease is still limited. This study was carried out to investigate the cytokine levels of tumour necrosis factor (TNF)-a, interleukin (IL)-1 beta, IL-4, IL-17 and IL-23 in the plasma of TAO patients presenting with acute clinical manifestations. The study included 20 TAO patients (n = 10 women; n = 10 men) aged 3859 years under clinical follow-up, classified into two groups: (i) TAO former smokers (n = 11) and (ii) TAO active smokers (n = 9); the control groups included normal volunteer non-smokers (n = 10, active smokers (n = 10) and former smokers (n = 10). Patients' plasma samples were measured using the sandwich enzyme-linked immunosorbent assay. Statistical analyses were performed using the non-parametric MannWhitney U-test, with parameters significant at P < 0.05. The activities of all cytokines were different in groups of TAO patients when compared with normal controls, and decreased for control smokers. Increased levels of TNF-a, IL-1 beta, IL-4, IL-17 and IL-23 were significant in patients with TAO when compared to the controls (P < 0.005, all parameters). The results presented here indicate an increased production of cytokines in TAO, possibly contributing to the inflammatory response observed in the patients' vascular levels. In addition, the increased levels of IL-17 and IL-23 suggest that the disturbance of TAO is involved with mechanisms of autoimmunity. Thus, the discovery of IL-17 and its association with inflammation and autoimmune pathology has reshaped our viewpoint regarding the pathogenesis of TAO, which was based previously on the T helper type 1 (Th1)Th2 paradigm.

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The objective of this study was to evaluate the route of administration of mannan-oligosaccharides in the diet of dairy calves and their effects on performance and plasma parameters indicative of rumen development. Following birth, twenty-four male Holstein calves were used in a completely randomized design and assigned to the following treatments: Control; 4 g/d Bio-Mos (R) (Alltech Biotech.) added to starter concentrate; and 4 g/d Bio-Mos (R) mixed into milk replacer. Animals were housed in individual hutches with free access to water, and fed 4L/d of milk replacer until weaning at six weeks. Calves also received 23g/kg crude protein of starter concentrate ad libitum. Fecal scores were evaluated daily. Body weights, growth measurements and blood samples for glucose, urea-N and beta-hidroxibutyrate analyses were taken weekly until 8 weeks of age. There were no significant effects of treatment or treatment x age interactions for mean starter concentrate intake, weight gain or body growth. However, there was a significant age effect for all parameters. Fecal scores were not affected by treatments. Also, plasma concentration of glucose, urea-N or beta-hidroxibutyrate were not affected by treatment or the treatment x age interaction. However, urea-N and beta-hidroxibutyrate concentrations significantly increased with age, suggesting adequate rumen development. Under the conditions of this study, there were no calf performance benefits when mannan-oligosaccharides were incorporated into milk replacer or calf starter concentrate.

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The flower industry represents about one billion dollars in Brazil and the development of techniques aimed at flowering control is required. This study evaluated the influence of gibberellic acid (GA3) on the vegetative and reproductive development of young plants of Phalaenopsis FSNT 'Dai-Itigo' hybrid pink color. The application of GA3 was made by foliar sprays at concentrations of 0, 125, 250, 500 and 1,000 mg L -1. The length of leaves increased significantly when using GA3 at low concentrations, but leaf width decreased. The application of GA3 at 125 mg L -1 showed the best results for the promotion of flowering and flower quality of this orchid hybrid. In this treatment, about 50% of plants treated with GA3 flowered about 6-12 months before the plants that were non-treated with this plant growth regulator. The quality of flowering and flowers was best with 125 mg L -1 GA3.

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Background. The surgical treatment of dysfunctional hips is a severe condition for the patient and a costly therapy for the public health. Hip resurfacing techniques seem to hold the promise of various advantages over traditional THR, with particular attention to young and active patients. Although the lesson provided in the past by many branches of engineering is that success in designing competitive products can be achieved only by predicting the possible scenario of failure, to date the understanding of the implant quality is poorly pre-clinically addressed. Thus revision is the only delayed and reliable end point for assessment. The aim of the present work was to model the musculoskeletal system so as to develop a protocol for predicting failure of hip resurfacing prosthesis. Methods. Preliminary studies validated the technique for the generation of subject specific finite element (FE) models of long bones from Computed Thomography data. The proposed protocol consisted in the numerical analysis of the prosthesis biomechanics by deterministic and statistic studies so as to assess the risk of biomechanical failure on the different operative conditions the implant might face in a population of interest during various activities of daily living. Physiological conditions were defined including the variability of the anatomy, bone densitometry, surgery uncertainties and published boundary conditions at the hip. The protocol was tested by analysing a successful design on the market and a new prototype of a resurfacing prosthesis. Results. The intrinsic accuracy of models on bone stress predictions (RMSE < 10%) was aligned to the current state of the art in this field. The accuracy of prediction on the bone-prosthesis contact mechanics was also excellent (< 0.001 mm). The sensitivity of models prediction to uncertainties on modelling parameter was found below 8.4%. The analysis of the successful design resulted in a very good agreement with published retrospective studies. The geometry optimisation of the new prototype lead to a final design with a low risk of failure. The statistical analysis confirmed the minimal risk of the optimised design over the entire population of interest. The performances of the optimised design showed a significant improvement with respect to the first prototype (+35%). Limitations. On the authors opinion the major limitation of this study is on boundary conditions. The muscular forces and the hip joint reaction were derived from the few data available in the literature, which can be considered significant but hardly representative of the entire variability of boundary conditions the implant might face over the patients population. This moved the focus of the research on modelling the musculoskeletal system; the ongoing activity is to develop subject-specific musculoskeletal models of the lower limb from medical images. Conclusions. The developed protocol was able to accurately predict known clinical outcomes when applied to a well-established device and, to support the design optimisation phase providing important information on critical characteristics of the patients when applied to a new prosthesis. The presented approach does have a relevant generality that would allow the extension of the protocol to a large set of orthopaedic scenarios with minor changes. Hence, a failure mode analysis criterion can be considered a suitable tool in developing new orthopaedic devices.

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Synthetic biology is a young field of applicative research aiming to design and build up artificial biological devices, useful for human applications. How synthetic biology emerged in past years and how the development of the Registry of Standard Biological Parts aimed to introduce one practical starting solution to apply the basics of engineering to molecular biology is presented in chapter 1 in the thesis The same chapter recalls how biological parts can make up a genetic program, the molecular cloning tecnique useful for this purpose, and an overview of the mathematical modeling adopted to describe gene circuit behavior. Although the design of gene circuits has become feasible the increasing complexity of gene networks asks for a rational approach to design gene circuits. A bottom-up approach was proposed, suggesting that the behavior of a complicated system can be predicted from the features of its parts. The option to use modular parts in large-scale networks will be facilitated by a detailed and shared characterization of their functional properties. Such a prediction, requires well-characterized mathematical models of the parts and of how they behave when assembled together. In chapter 2, the feasibility of the bottom-up approach in the design of a synthetic program in Escherichia coli bacterial cells is described. The rational design of gene networks is however far from being established. The synthetic biology approach can used the mathematical formalism to identify biological information not assessable with experimental measurements. In this context, chapter 3 describes the design of a synthetic sensor for identifying molecules of interest inside eukaryotic cells. The Registry of Standard parts collects standard and modular biological parts. To spread the use of BioBricks the iGEM competition was started. The ICM Laboratory, where Francesca Ceroni completed her Ph.D, partecipated with teams of students and Chapter 4 summarizes the projects developed.

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Histological serial sections, three-dimensional reconstructions and morphometry served to study the postnatal development of V1 in tree shrews. The main objectives were to evaluate the expansion of V1, the implications of its growth on the occipital cortex and, vice versa, the effects of the expanding neocortex on the topography of V1. The future V1 was identified on postnatal day 1 by its granular layer IV, covering the superior surface of the occipital cortices including the poles. A subdivision of layer IV, distinctive for the binocular part, was evident in the central region. V1 expanded continuously with age into all directions succeeded by the maturation of layering. The monocular part was recognized from day 15 onward, after the binocular part had reached its medial border. In reference to the retinotopic map of V1, regions emerged in a coherent temporo-spatial sequence delineating the retinal topography in a central to peripheral gradient beginning with the visual streak representation. The growth of V1 was greatest until tree shrews open their eyes, culminated during adolescence, and completed after a subsequent decrease in the young adult. Simultaneous expansion of the neocortex induced a shifting of V1. Translation and elongation of V1 entailed that the occipital cortex covered the superior colliculi along with a downward rotation of the poles. The enlargement of the occipital part of the hemispheres was in addition associated with the formation of a small occipital horn in the lateral ventricles, indicating an incipient 'true' occipital lobe harbouring mainly cortices involved in visual functions.

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During school-to-work transition, adolescents develop values and prioritize what is im-portant in their life. Values are concepts or beliefs about desirable states or behaviors that guide the selection or evaluation of behavior and events, and are ordered by their relative importance (Schwartz & Bilsky, 1987). Stressing the important role of values, career re-search has intensively studied the effect of values on educational decisions and early career development (e.g. Eccles, 2005; Hirschi, 2010; Rimann, Udris, & Weiss, 2000). Few re-searchers, however, have investigated so far how values develop in the early career phase and how value trajectories are influenced by individual characteristics. Values can be oriented towards specific life domains, such as work or family. Work values include intrinsic and extrinsic aspects of work (e.g., self-development, cooperation with others, income) (George & Jones, 1997). Family values include the importance of partner-ship, the creation of an own family and having children (Mayer, Kuramschew, & Trommsdroff, 2009). Research indicates that work values change considerably during early career development (Johnson, 2001; Lindsay & Knox, 1984). Individual differences in work values and value trajectories are found e.g., in relation to gender (Duffy & Sedlacek, 2007), parental background (Loughlin & Barling, 2001), personality (Lowry et al., 2012), educa-tion (Battle, 2003), and the anticipated timing of school-to-work transition (Porfeli, 2007). In contrast to work values, research on family value trajectories is rare and knowledge about the development during the school-to-work transition and early career development is lack-ing. This paper aims at filling this research gap. Focusing on family values and intrinsic work values and we expect a) family and work val-ues to change between ages 16 and 25, and b) that initial levels of family and work values as well as value change to be predicted by gender, reading literacy, ambition, and expected du-ration of education. Method. Using data from 2620 young adults (59.5% females), who participated in the Swiss longitudinal study TREE, latent growth modeling was employed to estimate the initial level and growth rate per year for work and family values. Analyses are based on TREE-waves 1 (year 2001, first year after compulsory school) to 8 (year 2010). Variables in the models included family values and intrinsic work values, gender, reading literacy, ambition and ex-pected duration of education. Language region was included as control variable. Results. Family values did not change significantly over the first four years after leaving compulsory school (mean slope = -.03, p =.36). They increased, however, significantly five years after compulsory school (mean slope = .13, p >.001). Intercept (.23, p < .001), first slope (.02, p < .001), and second slope (.01, p < .001) showed significant variance. Initial levels were higher for men and those with higher ambitions. Increases were found to be steeper for males as well as for participants with lower educational duration expectations and reading skills. Intrinsic work values increased over the first four years (mean slope =.03, p <.05) and showed a tendency to decrease in the years five to ten (mean slope = -.01, p < .10). Intercept (.21, p < .001), first slope (.01, p < .001), and second slope (.01, p < .001) showed signifi-cant variance, meaning that there are individual differences in initial levels and growth rates. Initial levels were higher for females, and those with higher ambitions, expecting longer educational pathways, and having lower reading skills. Growth rates were lower for the first phase and steeper for the second phase for males compared to females. Discussion. In general, results showed different patterns of work and family value trajecto-ries, and different individual factors related to initial levels and development after compul-sory school. Developments seem to fit to major life and career roles: in the first years after compulsory school young adults may be engaged to become established in one's job; later on, raising a family becomes more important. That we found significant gender differences in work and family trajectories may reflect attempts to overcome traditional roles, as over-all, women increase in work values and men increase in family values, resulting in an over-all trend to converge.

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Synaptic plasticity rules change during development: while hippocampal synapses can be potentiated by a single action potential pairing protocol in young neurons, mature neurons require burst firing to induce synaptic potentiation. An essential component for spike timing-dependent plasticity is the backpropagating action potential (BAP). BAP along the dendrites can be modulated by morphology and ion channel composition, both of which change during late postnatal development. However it is unclear whether these dendritic changes can explain the developmental changes in synaptic plasticity induction rules. Here, we show that tonic GABAergic inhibition regulates dendritic action potential backpropagation in adolescent but not pre-adolescent CA1 pyramidal neurons. These developmental changes in tonic inhibition also altered the induction threshold for spike timing-dependent plasticity in adolescent neurons. This GABAergic regulatory effect upon backpropagation is restricted to distal regions of apical dendrites (>200 μm) and mediated by α5-containing GABA(A) receptors. Direct dendritic recordings demonstrate α5-mediated tonic GABA(A) currents in adolescent neurons which can modulate backpropagating action potentials. These developmental modulations in dendritic excitability could not be explained by concurrent changes in dendritic morphology. To explain our data, model simulations propose a distally-increasing or localized distal expression of dendritic α5 tonic inhibition in mature neurons. Overall, our results demonstrate that dendritic integration and plasticity in more mature dendrites are significantly altered by tonic α5 inhibition in a dendritic region-specific and developmentally-regulated manner.