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131.
Onshore oil wells are dependent of maintenance services such as cleaning, reinstatement and stimulation. These services can be performed by a limited number of workover rigs. Usually, wells need maintenance services and a scheduling of the workover rigs must be defined. This scheduling must consider some factors such as the well production, the type of service to be performed and time windows for the service. There is a production loss associated to wells waiting for maintenance services, so it is important to attend them as soon as possible. Thus, the workover rig scheduling problem consists of finding the best schedule for the limited number of workover rigs, minimizing the production loss associated with the wells waiting for maintenance service. We present a simple and robust Simulated Annealing (SA) algorithm for solving this problem. Computational results on real problems obtained in Brazil are reported and SA presents better solutions than all those approaches reported in the literature.  相似文献   
132.
Ecotoxicity of naproxen and its phototransformation products   总被引:4,自引:0,他引:4  
The occurrence of pharmaceuticals in the environment is of great concern and only few data are available about the adverse effects of such molecules and their derivatives on non-target aquatic organisms. This study was designed to assess the toxic potential of Naproxen, a nonsteroidal anti-inflammatory, Naproxen Na, its freely water soluble sodium salt and their photoproducts in the aquatic environment. Bioassays were performed on algae, rotifers and microcrustaceans to assess acute and chronic toxicity. Furthermore, possible genotoxic effects of photoderivatives were investigated using SOS chromotest and Ames fluctuation test. The results showed that photoproducts were more toxic than the parent compounds both for acute and chronic values, while genotoxic and mutagenic effects were not found. These findings suggested the opportunity to consider derivatives in ecotoxicology assessment of drugs.  相似文献   
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A new strategy to prevent the biofouling of water-submerged surfaces is presented here. In particular, the authors showthat carbonic anydrase from Methanosarcina thermophila can be entrapped into polyacrylic paints, preserving enzyme activity. In addition, the authors also show that enzyme-containing paints inhibit the growth of marine microorganims, preventing biofouling.  相似文献   
135.
We previously reported that c-KIT+ human amniotic-fluid derived stem cells obtained from leftover samples of routine II trimester prenatal diagnosis (fetal hAFS) are endowed with regenerative paracrine potential driving pro-survival, anti-fibrotic and proliferative effects. hAFS may also be isolated from III trimester clinical waste samples during scheduled C-sections (perinatal hAFS), thus offering a more easily accessible alternative when compared to fetal hAFS. Nonetheless, little is known about the paracrine profile of perinatal hAFS. Here we provide a detailed characterization of the hAFS total secretome (i.e., the entirety of soluble paracrine factors released by cells in the conditioned medium, hAFS-CM) and the extracellular vesicles (hAFS-EVs) within it, from II trimester fetal- versus III trimester perinatal cells. Fetal- and perinatal hAFS were characterized and subject to hypoxic preconditioning to enhance their paracrine potential. hAFS-CM and hAFS-EV formulations were analyzed for protein and chemokine/cytokine content, and the EV cargo was further investigated by RNA sequencing. The phenotype of fetal- and perinatal hAFS, along with their corresponding secretome formulations, overlapped; yet, fetal hAFS showed immature oxidative phosphorylation activity when compared to perinatal ones. The profiling of their paracrine cargo revealed some differences according to gestational stage and hypoxic preconditioning. Both cell sources provided formulations enriched with neurotrophic, immunomodulatory, anti-fibrotic and endothelial stimulating factors, and the immature fetal hAFS secretome was defined by a more pronounced pro-vasculogenic, regenerative, pro-resolving and anti-aging profile. Small RNA profiling showed microRNA enrichment in both fetal- and perinatal hAFS-EV cargo, with a stably- expressed pro-resolving core as a reference molecular signature. Here we confirm that hAFS represents an appealing source of regenerative paracrine factors; the selection of either fetal or perinatal hAFS secretome formulations for future paracrine therapy should be evaluated considering the specific clinical scenario.  相似文献   
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Gluten‐free (GF) sourdough was prepared from wheat sourdough and analysed both in fresh (GFS) and dried forms (DGFS). The gluten content in each GF sourdough sample was <20 mg kg?1. The dough leavening capacity and the properties of the bread samples were investigated and compared to those of bread prepared using bakery yeast (Saccharomyces cerevisiae). Two commercial rice‐based mixtures (different for the presence/absence of buckwheat flour) were used to prepare bread samples. In GFS, lactic acid bacteria (LAB) and yeasts were found in amounts corresponding to 108 and 107 CFU g?1, respectively, whereas both LAB and yeasts were detected in lower amounts (about 106 CFU g?1) in DGFS. When used in bread‐making, both GFS types produced significant dough acidification and exhibited good dough development during proofing, resulting in loaves with specific volume values between 3.00 and 4.12 mL g?1, values similar to those obtained for reference bread (3.05÷4.15 mL g?1). The use of GFS was effective in lowering the bread staling rate during storage for up to 7 days.  相似文献   
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The effects of wall hydrocolloids on delivery and bioaccessibility of encapsulated brewers’ spent grain ACE-I inhibitory peptides after simulated gastrointestinal digestion were assessed. Microencapsulation of peptides was carried out by spray drying using locust bean gum, P. columbina phycocolloids, or its mixtures as wall materials. Microcapsules presented round external surfaces with some concavities, negative surface charge and encapsulation efficiencies higher than 90%. The incorporation of phycocolloids to formulations increased the encapsulation efficiency, negative surface charge and resistance against digestive enzymes of microcapsules. Encapsulated peptides with P. columbina phycocolloids showed lower IC50 value of ACE-I inhibition than un-encapsulated peptides (2.4 ± 0.2 vs. 7.2 ± 0.3 mg mL−1 protein), but higher than that obtained for hydrolysate (1.5 ± 0.2 mg mL−1 protein), indicating a 75% protection of bioactivity. Electrostatic and hydrophobic interactions between P. columbina phycocolloids and brewers’ spent grain peptides could be implicated in the protection of peptides during gastrointestinal digestion.  相似文献   
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