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Animals face strong environmental variability even on short time scales particularly in shallow coastal habitats, forcing them to permanently adjust their metabolism. Respiration rates of aquatic ectotherms are directly influenced by water temperature, whereas ingestion rates might additionally be influenced by behavior. We aim to understand how respiration and ingestion rates of an aquatic invertebrate respond to changing temperature during a diurnal thermal fluctuation cycle and how both processes are related. We studied the benthopelagic mysid Neomysis integer as an important food web component of coastal ecosystems. Mysids were collected at the southern Baltic Sea coast and exposed in the laboratory to either constant temperature of 15°C or daily temperature fluctuation of 15 ± 5°C. Short‐term (1–2 h) respiration and ingestion rates were measured at four equidistant time points within 24 h and did not differ among time points at constant temperature, but differed among time points in the fluctuating treatment. Respiration was highest at the thermal maximum and lowest at the thermal minimum. Ingestion rates showed the opposite pattern under fluctuation, likely due to differences in underlying thermal performance curves. When temperature transited the average, the direction of temperature change influenced the animals' response in respiration and ingestion rates differently. Our results suggest that respiration is not only instantaneously affected by temperature, but also influenced by the previously experienced direction of thermal change. Our experiment, using an important non‐model organism, delivered new insights on the relationship between the crucial organismal processes ingestion and respiration under thermal variability. [ABSTRACT FROM AUTHOR]

Abstract: Polyunsaturated fatty acids (PUFA), especially long-chain (i.e., [greater than or equal to]20 carbons) polyunsaturated fatty acids (LC-PUFA), are fundamental to the health and survival of marine and terrestrial organisms. [...]

Long-chain polyunsaturated fatty acids (LC-PUFA) are critical for the health of aquatic and terrestrial organisms; therefore, understanding the production, distribution, and abundance of these compounds is imperative. Although the dynamics of LC-PUFA production and distribution in aquatic environments has been well documented, a systematic and comprehensive comparison to LC-PUFA in terrestrial environments has not been rigorously investigated. Here we use a data synthesis approach to compare and contrast fatty acid profiles of 369 aquatic and terrestrial organisms. Habitat and trophic level were interacting factors that determined the proportion of individual omega-3 (n-3) or omega-6 (n-6) PUFA in aquatic and terrestrial organisms. Higher total n-3 content compared with n-6 PUFA and a strong prevalence of the n-3 PUFA eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) characterized aquatic versus terrestrial organisms. Conversely, terrestrial organisms had higher linoleic acid (LNA) and alpha-linolenic acid (ALA) contents than aquatic organisms; however, the ratio of ALA:LNA was higher in aquatic organisms. The EPA + DHA content was higher in aquatic animals than terrestrial organisms, and increased from algae to invertebrates to vertebrates in the aquatic environment. An analysis of covariance (ANCOVA) revealed that fatty acid composition was highly dependent on the interaction between habitat and trophic level. We conclude that freshwater ecosystems provide an essential service through the production of n-3 LC-PUFA that are required to maintain the health of terrestrial organisms including humans. Key words: aquatic ecosystems, conservation, eicosapentaenoic acid, docosahexaenoic acid, food webs. Les acides gras polyinsatures a longues chaines (LC-PUFA) sont critiques pour la sante des organismes aquatiques et terrestres, consequemment, la comprehension de la production, de la distribution et de l'abondance de ces composes merite une grande attention. Bien que la dynamique de la production et de la distribution des LC-PUFA dans les milieux aquatiques ait ete bien documentee, on n'a pas effectue rigoureusement et de facon systematique et integree une comparaison avec les LC- PUFA dans les milieux terrestres. Les auteurs utilisent ici une synthese de donnees pour comparer et contraster les profils des acides gras chez 369 organismes aquatiques et terrestres. L'habitat et le niveau trophique ressortent comme facteurs interactifs determinant la proportion des omegas-3 (n-3) ou des omegas-6 (n-6) individuels, entre les organismes aquatiques et terrestres. Une teneur totale plus elevee des PUFA n-3 comparativement aux n-6, et une forte prevalence des PUFA n-3 en acide eicosapentaenoique (EPA) et docosahexaeonique (DHA) caracterisent les organismes aquatiques contre terrestres. Reciproquement, les organismes terrestres montrent une plus forte teneur en acide linoleique (LNA) et alpha-linolenique (ALA) que les organismes aquatiques; cependant, le rapport ALA:LNA est plus eleve chez les organismes aquatiques. La teneur en EPA+DHA est plus elevee chez les animaux aquatiques que les animaux terrestres et augmente en passant des algues, aux invertebres et aux vertebres, en milieu aquatique. Une analyse en covariance revele que la composition en acides gras depend fortement de l'interaction entre l'habitat et le niveau trophique. On conclut que les ecosystemes d'eau douce fournissent un service essentiel par la production des LC-PUFA n-3 necessaires pour maintenir la sante les organismes terrestres incluant l'homme. [Traduit par la Redaction] Mots-cles: ecosystemes aquatiques, conservation, acide eicosapentaenoique, acide docosahexaeonique, chaine alimentaire., Introduction Long-chain (i.e., ≥ 20 carbons long) polyunsaturated fatty acids (LC-PUFA) are critically involved with key physiological functions of aquatic and terrestrial vertebrates, including humans, in supporting brain function, cardiovascular [...]

Background Defects at the forefoot frequently require microsurgical reconstruction; however, reconstructive failure can lead to results inferior to primary amputation. The purpose of this study was to identify independent factors affecting surgical outcomes and hospitalization time in these patients. Methods All patients that underwent free flap reconstruction of the forefoot between 2008 and 2019 were reviewed retrospectively. Statistical evaluation included binary logistic regression and correlation analysis. Results A total of 93 free flap procedures were performed in 87 patients. The most common defect etiologies were acute trauma (30 cases; 32.3%), diabetic foot syndrome (20 cases; 21.5%), and infection (17 cases; 18.3%). Muscle flaps were used in 50 cases (53.8%) and fasciocutaneous flaps were used in 43 cases (46.2%). Major complications occurred in 24 cases (25.8%) including 11 total flap losses and 2 partial flap losses. Minor complications occurred in 38 cases (40.9%). Patients aged 60 years or above were at significant higher risk of major complications (p = 0.029). Use of fasciocutaneous flaps (odds ratio [OR]: 14.341; p = 0.005), arterial hypertension (OR: 18.801; p = 0.014), and operative time (min) (OR: 1.010; p = 0.029) were identified as individual risk factors for major complications. Two venous anastomoses significantly reduced the risk of major complications (OR: 0.078; p = 0.022). Multiresistant bacterial wound colonization (OR: 65.152; p < 0.001) and defect size (OR: 1.007; p = 0.045) were identified as independent risk factors for minor complications. The median hospital stay was 28 days (7–85 days). Age significantly correlated with the length of hospital stay (r = 0.405, p < 0.01). Conclusion Our study identified independent risk factors that might help to make individual decisions whether to target microsurgical forefoot reconstruction or primary amputation. Two venous anastomoses should be performed whenever feasible, and muscle free flaps should be preferred in patients at higher risk of major surgical complications. [ABSTRACT FROM AUTHOR]