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Understanding the molecular mechanisms underlying individual responses to environmental changes is crucial for species conservation and management. Pelagic fishes including Atlantic herring (Clupea harengus) are of particular interest because of their key ecological and economic roles and their susceptibility to a changing ocean from global warming. Temperature and photoperiod have been linked with spawning time and location in adult herring, but no study has thus far investigated the role of environmental factors on gene regulation during the vulnerable early developmental stages. Here, we examine DNA methylation patterns of larval herring bred under two temperatures (11°C and 13°C) and photoperiod (6 and 12 h) regimes in a 2 × 2 factorial design. We found consistently high levels of global methylation across all individuals and a decline in global methylation with increased developmental stage that was more pronounced at 13°C (p ≤ 0.007) than at 11°C (p ≥ 0.21). Most of the differentially methylated sites were in exon and promoter regions for genes linked to metabolism and development, some of which were hypermethylated at higher temperature. These results demonstrate the important role of DNA methylation during larval development and suggest that this molecular mechanism might be key in regulating early‐stage responses to environmental stressors in Atlantic herring. [ABSTRACT FROM AUTHOR]

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Sintering of aluminum alloys is usually performed by the formation of a liquid phase. A liquid phase in 2xxx series alloys is formed from α+Al2Cu eutectic. In this work, the influences of trace elements like Sn or Pb, and the addition of a ceramic reinforcement, such as TiCN, on 2014 alloys are studied. Mechanical properties as well as a microstructural study show improved results. [ABSTRACT FROM AUTHOR]

Purpose: To analyze the utility of helical computed tomography (CT) in the diagnosis of suspected upper esophageal foreign bodies.Material and Methods: A prospective study was performed on 36 patients (26 F, 10 M, mean age 70 years) with a history of foreign body impaction. All had negative findings at indirect laryngoscopy. Radiologic assessment included unenhanced helical CT and a barium contrast study. Patients with positive findings were taken to esophagoscopy. All patients had a posterior clinical surveillance.Results: Twenty patients had both normal CT and barium study and satisfactory clinical outcome. In 12 patients a foreign body was noted in the cervical esophagus by CT, barium study, and endoscopy. In one patient a fish bone was detected by CT (and not by barium) confirmed with esophagoscopy. Another patient had a fish bone esophageal perforation which was observed only by CT and confirmed at surgery. Two patients with normal barium and endoscopy presented a false-positive CT result.Conclusion: Barium swallow is currently the first radiologic study, but may involve a risk of aspiration and can impede a subsequent esophagoscopy. Esophagoscopy is an invasive technique with a certain risk of serious complications that can be avoided with a satisfactory radiologic assessment. CT is easy, fast, has 100% sensitivity and is therefore the first choice technique for diagnosing suspected upper esophageal foreign bodies not expected to be visible on plain radiographs. [ABSTRACT FROM AUTHOR]

Four varieties of common bean seeds stored at 4 degrees C, 80% relative humidity, for one to eight years showed no differences in proximal chemical composition, Seeds 5-6 years old absorbed more water than 1 to 4 year-old seeds. The cooking time required for five year-old seeds was 6 hours, while the fresh seeds needed 3/4-to-one hour cooking time. The most remarkable difference was in phytic acid content, which decreased 94% to 98% during long storage. [ABSTRACT FROM AUTHOR]

The electrophoretic pattern of the untreated common bean globulin cv. Flor de Mayo had 7 protein fractions ranging from 620 to 120 kilodaltons (kd). The last molecular weight corresponds to the monomeric form. One of the objectives of the present work was to establish a comparison among denaturation by heat, sodium dodecyl sulphate (SDS) and dithiothreitol (DTT). At pH 6.0, two bands were resistant to heat treatment, after SDS treatment of the untreated globulin several bands disappeared and two new bands with 26 and 15 kd appeared. DTT did not change the electrophoretic pattern, due to the small quantity of free SH groups in the globulin. At pH 6.0, phaseolin is partly resistant to heat denaturation due to aggregation in an acidic environment. Isoelectrofocusing (IEF) and SDS polyacrylamide gel electrophoresis (SDS-PAGE) separated phaseolin into 10 protein fractions. The hypothesis is that phaseolin or globulin aggregation is due to the charge difference of fractions. [ABSTRACT FROM AUTHOR]