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41.
Recent advances in statistical mechanical theory can be used to solve a fundamental problem in experimental thermodynamics. In 1997, Jarzynski proved an equality relating the irreversible work to the equilibrium free energy difference, DeltaG. This remarkable theoretical result states that it is possible to obtain equilibrium thermodynamic parameters from processes carried out arbitrarily far from equilibrium. We test Jarzynski's equality by mechanically stretching a single molecule of RNA reversibly and irreversibly between two conformations. Application of this equality to the irreversible work trajectories recovers the DeltaG profile of the stretching process to within k(B)T/2 (half the thermal energy) of its best independent estimate, the mean work of reversible stretching. The implementation and test of Jarzynski's equality provides the first example of its use as a bridge between the statistical mechanics of equilibrium and nonequilibrium systems. This work also extends the thermodynamic analysis of single molecule manipulation data beyond the context of equilibrium experiments.  相似文献   
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The use of alternative materials to peat in soilless crop production, such as woody pruning wastes, has been reported by several researchers. In Mediterranean countries, several potential alternatives have been identified such as palm species or woody pruning wastes coming from different plant species. Mulberry (Morus alba L.) is a tree crop widely used in Europe for urban landscaping and to provide shade. Mulberry trees are pruned in sericulture two or three times a year to obtain a better yield of leaves. In an urban landscape, the trees are pruned once a year to form the canopy. Sorghum (Sorghum vulgare L.) is a cereal crop widely cultivated because it is considered the fourth most important summer crop in the world after soy, corn, and sunflower. It is one among the few resilient crops that can adapt well to future climate change conditions, particularly increasing drought, soil salinity, and high temperatures. After the harvest, the inedible parts of the plant, the stalks and leaves, are left over and must be disposed of, most of the time by burning. Palm trees in Spain, as in most of the European regions where palms are cultivated, are mainly used as ornamental plants in urban areas. One of the most commonly used palm tree in landscaping is the Canary Island date palm (Phoenix canariensis Hort. Ex Chavaud). These palm trees are pruned up to twice a year in this region, producing huge amounts of biomass that are disposed of in landfills. In this experiment, physical and chemical parameters were determined in the different particle sizes (<0.25, 0.25–1, 1–2, and 2–4 mm) of the raw residual materials from pruning activities of mulberry (Morus alba L.), sorghum (Sorghum vulgare L.), and palm (Phoenix canariensis) to evaluate their suitability for use as growing substrate. According to the results obtained, it can be concluded that the alternative materials for substrate preparation obtained from the pruning wastes of Morus alba (MAPW), Sorghum vulgare (SVPW), and Phoenix canariensis (PCPW) had suitable values of physical properties related to substrate porosity and wetting capacity. These materials also had high or very high total organic carbon (C) to total nitrogen (N) ratio values and low nutrient contents, except for potassium (K) in SVPW and PCPW.  相似文献   
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Members of the Toll-like receptor (TLR) and interleukin-1 receptor (IL-1R) superfamily share an intracytoplasmic Toll-IL-1 receptor (TIR) domain, which mediates recruitment of the interleukin-1 receptor-associated kinase (IRAK) complex via TIR-containing adapter molecules. We describe three unrelated children with inherited IRAK-4 deficiency. Their blood and fibroblast cells did not activate nuclear factor kappaB and mitogen-activated protein kinase (MAPK) and failed to induce downstream cytokines in response to any of the known ligands of TIR-bearing receptors. The otherwise healthy children developed infections caused by pyogenic bacteria. These findings suggest that, in humans, the TIR-IRAK signaling pathway is crucial for protective immunity against specific bacteria but is redundant against most other microorganisms.  相似文献   
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In Chile, prolonged transport of cattle is an important issue due to geographical conditions. This study describes the variation of body weight and some blood constituents related to stress response during one long distance transport (63 h) of recently weaned calves for fattening in the Chilean Patagonia. Results concerning blood variables related to stress showed that the whole process of rounding up, weaning and transport was stressful for the calves and that animal welfare was impaired. Cortisol values were significantly lower after unloading (1.0±0.4 μg/dl), as compared to before loading (1.5±0.4 μg/dl). The significant body weight loss from before loading (240±26.9 kg) to after unloading (210±24.2 kg), and the long recovery time, adds economic losses to the producers at destiny. As transport period cannot be shortened due to the typical Chilean geography in the Patagonian region and the scarcity of proper routes, it is recommended that conditions of transported calves should be improved by using specialized livestock vehicles that can provide more comfort, as well as access to water and food during the journey.  相似文献   
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Objective

To determine the microglial and astrocyte response to painful lameness in horses.

Study design

Ionized calcium binding adaptor molecule 1 (Iba-1) and glial fibrillary acidic protein (GFAP) expression, cell density and morphology were determined through immunofluorescence within the dorsal horn of equine spinal cord.

Animals

A total of five adult horses with acute or chronic unilateral lameness, previously scheduled for euthanasia.

Methods

Musculoskeletal lameness was evaluated in five horses through visual evaluation according to clinical guidelines. Spinal cord samples were obtained immediately after euthanasia, and distal limb lesions were confirmed through dissection and radiography. Iba-1 immunostaining was used for detection and characterization of dorsal horn microglia. GFAP was used for immunostaining of dorsal horn astrocytes. Iba-1 and GFAP labeled cells were quantified in the dorsal horn, and intensity of fluorescence was compared between the ipsi- and contralateral dorsal horn to the affected limb, and between dorsal horn segments of all horses.

Results

Iba-1 expression was higher in the ipsilateral dorsal horn of the affected limb in contrast to the contralateral side dorsal horn. GFAP markers did not demonstrate increased astrocytic activity on the dorsal horn ipsilateral side to the distal limb lesion of affected horses. Horses with acute lameness predominantly had a spherical shape microglial phenotype, while cells from chronic lameness cases had variable morphology. Astrocytes evidenced small somas and large processes in both acute and chronic lameness, with higher GFAP localization in the main branches. As in the case of rodents, the localization of microglia and astrocytes in horses was mainly situated within laminae I, II and III.

Conclusions and clinical relevance

Iba-1 and GFAP are functional and morphological markers of spinal microglial cells and astrocytes in horses with lameness.  相似文献   
49.
During the present study, we aimed at providing a first look at the elemental composition of the early stages of cephalopods as an approach to their elemental requirements in culture. Essential and non-essential elemental profiles of the European cuttlefish Sepia officinalis, the European squid Loligo vulgaris and the common octopus Octopus vulgaris laboratory hatchlings and wild juveniles were analysed. In addition, for O. vulgaris we determined elemental profiles of mature ovary, eggs in different stages of development and followed possible effects of four dietary treatments during paralarval rearing, also analyzing elemental content of the live preys Artemia nauplii and Maja brachydactyla hatchling zoeae. Content was determined for essential (As, Ca, Cr, Co, Cu, Fe, K, Mg, Mn, Na, Ni, P, Rb, S, Sr, Zn) and non-essential (Ag, Al, Ba, Cd, Hg, Pb) elements. The content in non-essential elements found in hatchlings and juveniles of the three species analyzed here seems to be far lower in comparison with subadult and adult stages of coastal cephalopods. In the octopus eggs, the non-essential element concentrations remained globally low compared to hatchlings and juveniles indicating the absorption of these elements along the ontogenetic development. The elemental composition of the octopus ovary and of the eggs, hatchlings and juveniles of the three cephalopod species analyzed here showed a high content in S. As expected, the calcified internal shell of the cuttlefish, rich in Ca and Sr, originates the main difference between species. It is remarkable the richness in Cu of hatchling octopus, that may indicate a particular nutritional requirement for this element during the planktonic life. The reared octopus paralarvae feed on Artemia nauplii, a prey with relatively low Cu content, showed nearly half Cu content that the “natural” profile of octopus hatchlings or wild juveniles. This suggests a dietary effect and/or an indication of the poor physiological stage of the Artemia-fed paralarvae. At the present, the percentage of essential element absorption by food or seawater is unknown for cephalopods and should be determined in the future to understand their feeding requirements in culture.  相似文献   
50.
Plant Foods for Human Nutrition - In recent years, interest in plant-based proteins has been rising due to ethical and sustainability issues. In this context, the production of protein concentrates...  相似文献   
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