358 resultados para Atta sexdens


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Highly selective Cav2.2 voltage-gated calcium channel (VGCC) inhibitors have emerged as a new class of therapeutics for the treatment of chronic and neuropathic pain. Cone snail venoms provided the first drug in class with FDA approval granted in 2005 to Prialt (ω-conotoxin MVIIA, Elan) for the treatment of neuropathic pain. Since this pioneering work, major efforts underway to develop alternative small molecule inhibitors of Cav2.2 calcium channel have met with varied success. This review focuses on the properties of the Cav2.2 calcium channel in different pain states, the action of ω-conotoxins GVIA, MVIIA and CVID, describing their structure-activity relationships and potential as leads for the design of improved Cav2.2 calcium channel therapeutics, and finally the development of small molecules for the treatment of chronic pain.

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The structure and spin-crossover magnetic behavior of [FeII16][BF4]2 (1 = isoxazole) and [FeII16][ClO4]2 have been studied. [FeII16][BF4]2 undergoes two reversible spin-crossover transitions at 91 and 192 K, and is the first two-step spin transition to undergo a simultaneous crystallographic phase transition, but does not exhibit thermal hysteresis. The single-crystal structure determinations at 260 [space group P3̄, a = 17.4387(4) Å, c = 7.6847(2) Å] and at 130 K [space group P1̄, a = 17.0901(2) Å, b = 16.7481(2) Å, c = 7.5413(1) Å, α = 90.5309(6)°, β = 91.5231(6)°, γ = 117.8195(8)°] reveal two different iron sites, Fe1 and Fe2, in a 1:2 ratio. The room-temperature magnetic moment of 5.0 μB is consistent with high-spin Fe(II). A plateau in μ(T) having a moment of 3.3 μB centered at 130 K suggests a mixed spin system of some high-spin and some low-spin Fe(II) molecules. On the basis of the Fe−N bond distances at the two temperatures, and the molar fraction of high-spin molecules at the transition plateau, Fe1 and Fe2 can be assigned to the 91 and 192 K transitions, respectively. [FeII16][ClO4]2 [space group P3̄, a = 17.5829(3) Å, c = 7.8043(2) Å, β = 109.820 (3)°, T = 295 K] also possesses Fe1:Fe2 in a 1:2 ratio, and magnetic measurements show a single spin transition at 213 K, indicating that both Fe1 and Fe2 undergo a simultaneous spin transition. [FeII16][ClO4]2 slowly decomposes in solutions containing acetic anhydride to form [FeIII3O(OAc)613][ClO4] [space group I2, a = 10.1547(7) Å, b = 16.5497(11) Å, c = 10.3205(9) Å, β = 109.820 (3)°, T = 200 K]. The isosceles Fe3 unit contains two Fe···Fe distances of 3.2844(1) Å and a third Fe···Fe distance of 3.2857(1) Å. The magnetic data can be fit to a trinuclear model with ℋ = −2J(S1·S2 + S2·S3) − 2J13(S1·S3), where J = −27.1 and J13 = −32.5 cm-1.

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This study examined whether high nutrient concentrations associated with leaf-cutting ant nests influence plant growth and plant water relations in Amazon rain forests. Three nests of Atta cephalotes were selected along with 31 Amaioua guianensis and Protium sp. trees that were grouped into trees near and distant (>10 m) from nests. A 15N leaf-labelling experiment confirmed that trees located near nests accessed nutrients from nests. Trees near nests exhibited higher relative growth rates (based on stem diameter increases) on average compared with trees further away; however this was significant for A. guianensis (near nest 0.224 y−1 and far from nest 0.036 y−1) but not so for Protium sp. (0.146 y−1 and 0.114 y−1 respectively). Water relations were similarly species-specific; for A. guianensis, near-nest individuals showed significantly higher sap flow rates (16 vs. 5 cm h−1), higher predawn/midday water potentials (−0.66 vs. −0.98 MPa) and lower foliar δ13C than trees further away indicating greater water uptake in proximity to the nests while the Protium sp. showed no significant difference except for carbon isotopes. This study thus shows that plant response to high nutrient concentrations in an oligotrophic ecosystem varies with species. Lower seedling abundance and species richness on nests as compared with further away suggests that while adult plants access subterranean nutrient pools, the nest surfaces themselves do not encourage plant establishment and growth.

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The objective of this study was to evaluate the effects of the use of cashew bagasse bran (CBB) as food ingredient in qualitative feed restriction programs on the carcass traits, meat quality, organs weight and intestinal morphometry of barrows and gilts. Twenty – four crossbred pigs were used (12 barrows and 12 gilts) with an average initial body weight of 57.93 ± 3.67 kg/LW. The experimental designs was in randomized blocks 3x2 factorial arrangement with three level (0%, 15% e 30% CBB), two genders (barrows and gilts) and four repetition. A total of twenty-four instalments. The treatments were composed of basal diet (BD) formulated with corn, soybean meal and commercial base mix for finishing pigs, being containing different levels of CBB. At the end of the trial period the animals were slaughtered for the evaluation of the meat quality, traits carcass, Absolute Weight (AW) and Relative Weight (RW) of the organs and morphometric study of small intestine fragment. The inclusion of (CBB) in the diets did not affect the traits carcass of gilts, but interfered in the traits carcass of the barrow positively, increasing the yield of meat into cold carcass and reducing the thickness of subcutaneous fat, without affecting the fatty acid profile. However, we observed increased weight of organs and partial volume of absortiva mucosa of gilts. In the comparison between sex was observed a greater liver weight (AW) and (RW), and surface density of absortiva mucosa of barrow. The use of CBB was considered as ingredient to be used in programs of qualitative feed restriction for finishing pigs.

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The objective of this study was to evaluate the effects of the use of cashew bagasse bran (CBB) as food ingredient in qualitative feed restriction programs on the carcass traits, meat quality, organs weight and intestinal morphometry of barrows and gilts. Twenty – four crossbred pigs were used (12 barrows and 12 gilts) with an average initial body weight of 57.93 ± 3.67 kg/LW. The experimental designs was in randomized blocks 3x2 factorial arrangement with three level (0%, 15% e 30% CBB), two genders (barrows and gilts) and four repetition. A total of twenty-four instalments. The treatments were composed of basal diet (BD) formulated with corn, soybean meal and commercial base mix for finishing pigs, being containing different levels of CBB. At the end of the trial period the animals were slaughtered for the evaluation of the meat quality, traits carcass, Absolute Weight (AW) and Relative Weight (RW) of the organs and morphometric study of small intestine fragment. The inclusion of (CBB) in the diets did not affect the traits carcass of gilts, but interfered in the traits carcass of the barrow positively, increasing the yield of meat into cold carcass and reducing the thickness of subcutaneous fat, without affecting the fatty acid profile. However, we observed increased weight of organs and partial volume of absortiva mucosa of gilts. In the comparison between sex was observed a greater liver weight (AW) and (RW), and surface density of absortiva mucosa of barrow. The use of CBB was considered as ingredient to be used in programs of qualitative feed restriction for finishing pigs.

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Purpose. Advanced cancer patients with disease progression develop cachexia. Nevertheless, cancer patients at nutritional risk have shown improved body weight and quality of life with oral nutritional supplements. Method. This was a randomized controlled trial in adult female cancer patients (n = 63) attending palliative clinics, with symptoms of cachexia. Eligible patients were randomly distributed into control (n = 33) and intervention (n = 30) groups. Both groups were provided with nutritional and physical activity counseling, but the intervention group received an additional 100 g of Improved Atta (IAtta) for 6 months daily consumption. This study was designed to assess the efficacy of IAtta (with counseling) in enhancing the health status of cachexic patients. Anthropometric measurements, dietary intake, physical activity level and quality of life parameters were assessed at baseline, after 3 months, and at the end of 6 months. Results. Patients in the control group (n = 15) had significantly decreased body weight (P = .003), mid–upper-arm circumference (P = .002), and body fat (P = .002) by the end of intervention. A trend of body weight gain in the intervention group (n = 17; P = .08) and significant increase of body fat (P = .002) was observed; moreover, patients reported a significant improvement in fatigue (P = .002) and appetite scores (P = .006) under quality-of-life domains at the end of intervention. Conclusions. Embedding a nutrition-sensitive intervention ( IAtta ) within Indian palliative care therapy may improve quality of life and stabilize body weight in cancer cachexia patients.

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Multiuser selection scheduling concept has been recently proposed in the literature in order to increase the multiuser diversity gain and overcome the significant feedback requirements for the opportunistic scheduling schemes. The main idea is that reducing the feedback overhead saves per-user power that could potentially be added for the data transmission. In this work, the authors propose to integrate the principle of multiuser selection and the proportional fair scheduling scheme. This is aimed especially at power-limited, multi-device systems in non-identically distributed fading channels. For the performance analysis, they derive closed-form expressions for the outage probabilities and the average system rate of the delay-sensitive and the delay-tolerant systems, respectively, and compare them with the full feedback multiuser diversity schemes. The discrete rate region is analytically presented, where the maximum average system rate can be obtained by properly choosing the number of partial devices. They optimise jointly the number of partial devices and the per-device power saving in order to maximise the average system rate under the power requirement. Through the authors’ results, they finally demonstrate that the proposed scheme leveraging the saved feedback power to add for the data transmission can outperform the full feedback multiuser diversity, in non-identical Rayleigh fading of devices’ channels.

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Questa tesi svolta nell’ambito della geotecnica ha L’obiettivo di porre l’attenzione sul comportamento dei cedimenti secondari, quindi sul coefficiente di consolidazione secondaria Cα mediante l’esecuzione di una prova edometrica su di una sezione di campione estratto in sito, dove si evidenzia una percentuale di contenuto organico molto alta (torba).Si introduce il concetto di terreno organico a partire dalla genesi fino ad una classificazione atta a distinguere terreni con percentuali di componente organica differenti. Si spiega la teoria della consolidazione monodimensionale, quindi la prova edometrica, riportando in maniera grafica e analitica tutti i coefficienti che da essa si possono ricavare a partire dai parametri di compressione volumetrica fino alla consolidazione primaria e secondaria (o creep)si descrivono dettagliatamente la strumentazione e la procedura di prova. Descrivendo l’edometro utilizzato in laboratorio e tutti gli accessori ad esso collegati, il campione da analizzare, la procedura di preparazione del campione alla prova edometrica, trovando alcune proprietà fisiche del campione, come il contenuto d’acqua e il contenuto organico, ed in fine riportando i passaggi della prova edometrica in modo tale da poter essere riprodotta.Si analizzano tutti i risultati ottenuti durante la prova in maniera analitica e grafica, osservando e commentando la forma dei grafici ottenuti in relazione al materiale che compone il campione ed i tempi impiegati per eseguire la prova.

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Il mio elaborato si pone come obiettivo il miglioramento di una macchina di condizionamento atta al funzionamento a temperature inferiori allo standard nazionale (circa -20°C, -253,15 K). Il lavoro si basa sullo studio di un sistema innovativo di sbrinamento per pompe di calore ad alta efficienza che necessiti nel minor modo possibile di manutenzione, sia di facile installazione e permetta alla macchina di mantenere il rendimento intorno a valori accettabili. Dopo aver portato avanti un'analisi energetica del sistema, attraverso lo studio di diverse possibilità di sbrinamento, l'elaborato verifica che l'installazione del sistema progettato porti ad un effettivo vantaggio anche dal punto di vista economico.

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Bioactive compounds are extra nutritional constituents occurring naturally in plant foods in small amounts, however in quantities enough to produce bioactive effects. Among bioactive compounds the phenolic compounds are a very large set of molecules, which include several groups such as for example flavonoids, phenolic acids or tannins. Small fruits and berries include a wide diversity of fruits, like grapes, strawberries, blackberries, blueberries, raspberries, cherries, hardi kiwi, gooseberries, cranberries, currants (black, white, red), physalis, crowberries, açaí, elderberries, dates or goji berries, and these frequently have been reported as having particularly high concentrations of phenolic compounds with antioxidant activity. Hence, the objective of this chapter is to review the literature about the type and contents of different phenolic compounds present in small fruits and berries, as well as their bioactive properties, including antioxidant capacity. All the fruits and berries investigated in this chapter were particularly rich in bioactive compounds, including phenolic compounds that provide the fruits with high antioxidant properties. The most relevant health promoting effects include anti-cancer, anti-inflamatory, neuro protective, cardio protective or anti-diabetes, thus indicating that these foods are a valuable resource to prevent and treat diseases.

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Introducción Los sistemas de puntuación para predicción se han desarrollado para medir la severidad de la enfermedad y el pronóstico de los pacientes en la unidad de cuidados intensivos. Estas medidas son útiles para la toma de decisiones clínicas, la estandarización de la investigación, y la comparación de la calidad de la atención al paciente crítico. Materiales y métodos Estudio de tipo observacional analítico de cohorte en el que reviso las historias clínicas de 283 pacientes oncológicos admitidos a la unidad de cuidados intensivos (UCI) durante enero de 2014 a enero de 2016 y a quienes se les estimo la probabilidad de mortalidad con los puntajes pronósticos APACHE IV y MPM II, se realizó regresión logística con las variables predictoras con las que se derivaron cada uno de los modelos es sus estudios originales y se determinó la calibración, la discriminación y se calcularon los criterios de información Akaike AIC y Bayesiano BIC. Resultados En la evaluación de desempeño de los puntajes pronósticos APACHE IV mostro mayor capacidad de predicción (AUC = 0,95) en comparación con MPM II (AUC = 0,78), los dos modelos mostraron calibración adecuada con estadístico de Hosmer y Lemeshow para APACHE IV (p = 0,39) y para MPM II (p = 0,99). El ∆ BIC es de 2,9 que muestra evidencia positiva en contra de APACHE IV. Se reporta el estadístico AIC siendo menor para APACHE IV lo que indica que es el modelo con mejor ajuste a los datos. Conclusiones APACHE IV tiene un buen desempeño en la predicción de mortalidad de pacientes críticamente enfermos, incluyendo pacientes oncológicos. Por lo tanto se trata de una herramienta útil para el clínico en su labor diaria, al permitirle distinguir los pacientes con alta probabilidad de mortalidad.