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A comprehensive characterization of key mechanisms underlying signal transmission within the human brain remains an unsolved problem. The neuronal surface, composed principally of phosphatidylcholine (POPC), has a known ordering effect on water. This produces highly organized water layers (OWLs) at the neuron-water interface--the neurochemical implications of which are not currently understood. The human brain is 75% water by volume, with folds and grooves to maximize surface area, suggesting that characterization of neuronal OWLs may contribute to an understanding of neuronal signal transmission. Previous experimental work has measured enhanced conductivity of POPC OWLs relative to bulk water. The mechanism underlying this conductivity is still debated. Using quantum chemical methods on a POPC-water interface model system, we present data characterizing OWL conductance. Non-equilibrium Green's function calculation results demonstrate that there is negligible electron transfer-based conductivity through the OWL at biological temperatures. This is consistent with existing studies suggesting the Grotthuss mechanism as the most likely explanation for experimentally observed enhanced conductivity at the POPC-water interface. The broader implications of enhanced proton conductivity at the neuron-water interface are discussed. Key words: interfacial water, organized water, conductance, neuronal lipid, quantum chemical, Introduction The main function of the brain is the transmission and processing of information. Traditionally this has been conceptualized within the context of synaptic transmission. However, the search for alternative [...]

Oyster population maintenance and growth require a sufficient larval supply competent for metamorphosis and settlement. Larval performance, in terms of growth, development, survival, and metamorphic success, determines the capacity for a larval cohort to effectively settle and establish into an existing population. Exogenous factors influencing larval development include temperature, salinity, food quantity, and food quality. A sufficient diet, composed of balanced protein, lipids, and carbohydrates to meet larval nutritional demands, is required to promote successful metamorphosis. To evaluate the influence of these exogenous factors on oyster settlement potential in Delaware Bay, a well-established biochemically based Crassostrea gigas (Thunberg, 1793) larval model was adapted to simulate Crassostrea virginica (Gmelin, 1791) larval performance under in situ environmental conditions measured during the 2009 to 2011 reproductive seasons at 10 sites across the salinity gradient of Delaware Bay. Variation in the initial egg size and lipid content, and larval food assimilation efficiency was incorporated into the model to represent potential within-cohort phenotypic variability. The middle portion of Delaware Bay along the New Jersey shoreline, bridging the 15-salinity line, generated the most successful larvae each year, whereas the low-salinity reach, on the Delaware side, and Nantuxent Point Reef had more variable success. Survivorship was a function of adequate temperatures and salinities, sufficient food quantity, and favorable food quality defined in part by the protein-to-(lipid-plus-carbohydrate) ratio. Most settlement was predicted by the model to occur between July and September of each year. To validate the model, estimated settlement windows were compared with calculated settlement windows derived from recruitment observations on yearly shell plants. Modeled and recruitment-derived settlement windows agreed well with each other and verified the capacity of the model to accurately forecast in situ larval performance. The oyster larval model, based on measures of lipid, protein, and carbohydrate, successfully passed an important field test, demonstrating the potential of such biochemically based models to reliably evaluate larval performance under real-world conditions. KEY WORDS: Crassostrea virginica, larvae, eastern oyster, performance model, settlement window, biochemical, food, INTRODUCTION Successful oyster population maintenance and growth require a consistent larval supply capable of settlement onto existing beds over time (Coen & Luckenbach 2000, Mann & Powell 2007, Lipcius et [...]

Author(s): Ismail Tarhan [sup.1] , Seküre Çelikten [sup.1] , Hafize Merve Kestek [sup.1] , Murat Türkteki [sup.2] Author Affiliations: (1) grid.17242.32, 0000 0001 2308 7215, Selçuk University, Faculty of Science, [...], In this study, parameters of an acid-catalyzed direct extraction methylation method used for the determination of low-level lipid residues in the ceramic artifacts were investigated and optimized as a result of chemometric modeling techniques that enable comprehensive statistical data to be obtained with fewer analyses in the optimization studies. For this purpose, 25 amorphous unglazed ceramic artifacts found during the 1996-2021 excavations at the Küllüoba Höyük archaeological site were subjected to lipid residue determination. The ceramic samples extracted by the proposed method were analyzed by gas chromatography-mass spectrometry, and the lipid residues present in them were determined. According to the obtained fatty acid composition results, it can be said that the lipid residues in the analyzed ceramics are of both animal and plant origin. The ceramic artifact with the highest lipid residue concentration was selected, and the parameters of the extraction method were examined using the chemometric models. According to the response surface methodology, the extraction time and temperature should be high as long as the experimental conditions and environment allow for the extraction of the lipid residues in the ceramic artifacts, and the silylation process has a limited positive effect on the yield, but the extraction with methanol can be achieved successfully when the silylation process is not performed.

Ocean-related global changes have altered phytoplankton community structure, especially the diatom-dinoflagellate competition, which further influences ecosystem structure and functions. The pivotal ecological roles of diatoms and dinoflagellates are strongly related with their biochemical composition, but quantitative comparisons of biochemical changes between diatoms and dinoflagellates under variable environments are still limited. We investigated responses of lipid biomarkers (sterols and fatty acids (FAs)) to different temperatures (12, 18 and 24 °C), nitrogen and phosphorus concentrations and their molar ratios (N:P ratios) of 10:1, 24:1 and 63:1 in marine diatom Phaeodactylum tricornutum and dinoflagellate Prorocentrum minimum. Over these wide ranges of temperature and nutrient conditions, sterol and FA profiles were relatively stable in the two species. For carbon-normalized contents of major lipid biomarkers, warming caused non-significant changes in the diatoms but an increase (up to 153%) in the dinoflagellates. Eutrophication caused an overall decrease (up to 53%) in major lipid biomarker contents in the diatoms but an overall increase (up to 77%) in the dinoflagellates. In contrast, imbalanced N:P ratios caused an overall increase (up to 64%) in major lipid biomarker contents in the diatoms but an overall decrease (up to 53%) in the dinoflagellates. Taken together, our results showed that the contents of major sterols and polyunsaturated FAs would change non-significantly in the diatom P. tricornutum, while those in the dinoflagellate P. minimum would increase (ca. 9-48%) under future ocean warming, eutrophication and imbalanced N:P ratios. This study expands our knowledge on lipid-based indicators of phytoplankton under changing environments, which by systematically linking with several other aspects of food quality will help to understand ecological consequences of diatom-dinoflagellate community changes., Author(s): Zhong Cao [sup.1] [sup.2] , Rong Bi [sup.1] [sup.2] , Chuanli Zhang [sup.1] [sup.2] , Jiaxuan Cui [sup.1] [sup.2] , Li Li [sup.1] [sup.2] , Yang Ding [sup.1] [sup.2] [...]

Microalgae are a sustainable source of lipids for industrial applications. In this study, we tested the effect of three chemical elicitors [chitosan, methyl jasmonate (MeJA), and flavonoids] on lipid accumulation in the microalga Scenedesmus. We analyzed the effect of different concentrations of these elicitors at different time points on growth rate and lipid production. We found that these elicitors did not have an adverse effect on the growth rate of Scenedesmus at different time points, by comparison with their respective controls. Among the three elicitors, MeJA at a low concentration (25 [micro]L/L) was found to be effective at enhancing the lipid production in Scenedesmus when added at the time of harvest and allowed to react for 12 h, whereas flavonoid treatment, specifically at 0.5 mg/L, enhanced lipid production after 24 h. Fatty acid methyl ester analysis by GC-MS revealed no difference in lipid profile before or after chemical induction. Taken together, this comparative analysis highlights the potential of MeJA at a low concentrations to be effective at improving lipid productivity without altering the growth rate in Scenedesmus. Key words: biofuel, microalgae, lipid production, chemical elicitor. Les microalgues constituent une source durable de lipides pour des applications industrielles. Dans la présente étude, les auteurs ont testé l'effet de trois éliciteurs chimiques (le chitosane, le jasmonate de méthyle [MeJA] et les flavonoïdes) sur l'accumulation de lipides dans la microalgue Scenedesmus. Ils ont analysé l'effet de différentes concentrations de ces éliciteurs à différents moments sur le taux de croissance et la production de lipides. Ils ont constaté que ces éliciteurs n'exerçaient pas d'effet négatif sur le taux de croissance de Scenedesmus à différents moments par rapport à leurs témoins respectifs. Parmi les trois éliciteurs, le MeJA à faible concentration (25 [micro]L/L) s'est avéré efficace pour améliorer la production de lipides chez Scenedesmus lorsqu'il était ajouté au moment de la récolte et qu'on le laissait réagir pendant 12 h, tandis que le traitement aux flavonoïdes améliorait la production de lipides après 24 h de traitement, en particulier à une concentration de 0,5 mg/L. L'analyse des esters méthyliques d'acides gras par GC-MS n'a révélé aucune différence dans le profil lipidique avant et après l'élicitation chimique. Dans l'ensemble, cette analyse comparative met en évidence le potentiel du MeJA à faible concentration en tant qu'éliciteur efficace pour améliorer la productivité des lipides sans modifier le taux de croissance de Scenedesmus. [Traduit par la Rédaction] Mots-clés: biocarburants, microalgues, production de lipides, éliciteur chimique., Introduction The use of microalgae as a potential biofuel and feedstock has been promoted as the next frontier of green biotechnology. Microalgae are regarded as the most productive photosynthetic biomass [...]

Lipids are key compounds in the transfer of energy and nutrients in marine food webs. Specifically, neutral lipids are the main reservoir of dietary energy in most marine animals and are often used as indicators of nutritional condition. In contrast, polar lipids, including acetone-mobile polar lipids and phospholipids, are key structural components of cell membranes. Here, we explored the fatty acid (FA) composition across the neutral and polar lipid fractions in benthic organisms belonging to five major phyla (Arthropoda, Cnidaria, Echinodermata, Mollusca, and Porifera), which were collected from a deep-water region in the Northwest Atlantic. Overall, the FA composition of acetone-mobile polar lipids (e.g., glycolipids) and phospholipids was more similar to each other and characterized by higher proportions of saturated FA (e.g., 16:0) compared to that of neutral lipids. This result reflected the different functions (structural vs storage) of these lipid fractions. Furthermore, independently of the taxon, monounsaturated FA (e.g., 16:1[omega]7, 18:1[omega]9) were dominant in neutral lipids, suggesting their preferential utilization for energy production. Whereas several species, including the gastropod Buccinum sp., retained the essential polyunsaturated FA (i.e., [omega]3 and [omega]6 FA) in their neutral lipids, others, such as the crustacean Pasiphaea tarda and the echinoderm Phormosoma placenta incorporated them into their polar lipids, pointing to differences in the metabolism of essential FA across species. These findings highlight the value of quantifying differences among lipid fractions. Last, the relatively high content of essential FA in neutral lipids of most species suggested a dietary surplus indicating a healthy, productive food web., Author(s): Camilla Parzanini [sup.1] [sup.2] , Nurgül Sen Özdemir [sup.1] [sup.3] , Laura Carreón-Palau [sup.1] [sup.4] , Christopher C. Parrish [sup.1] Author Affiliations: (1) grid.25055.37, 0000 0000 9130 6822, Department [...]

Long-term carbon (C) stabilisation in tropical and subtropical soils under no-tillage (NT) rests on the formation of mineral-organic associations (MOAs) that can be enriched with microbial metabolites. In this work, we assessed the role of long-term tillage and cropping systems and mineral N fertilisation in enriching MOAs with microbial metabolites in a subtropical soil. For this purpose, we sampled a sandy clay loam Acrisol up to 1 m depth involved in an ongoing 30-year-old experiment under two different tillage systems (conventional tillage and NT) in the presence and absence of legume cover crops and mineral nitrogen (N) fertilisation. The soil samples were subjected to particle size fractionation and n-alkane analysis. The NT and the presence of legume cover crops in the surface soil layer (0-5 cm) increased the abundance of plant-derived lipids (i.e. compounds with n-alkane chains of 25-33 C atoms) in the whole soil. Microbial-derived lipids (i.e. compounds with shorter n-alkane chains (15-24 C atoms)) were more abundant in the clay fraction of the surface (0-5 cm) and sub-surface soil layers (20-30 and 75-100 cm) in NT soil receiving high-quality residues of legume cover crops. However, N fertilisation decreased the abundance of microbial-derived lipids in the clay fraction of the 0-5 and 20-30 cm soil layers. Our findings highlight the role ofN-rich residues of legume cover crops, but not of mineral N fertilisation, in the long-term stabilisation of C in MOAs in NT soils through the action of microbial residues. Additional keywords: n-alkanes, no-tillage, soil carbon accumulation, soil lipids. Received 30 May 2019, accepted 13 August 2019, published online 19 September 2019, Introduction No-tillage (NT) is a widespread method of facilitating storage of organic carbon (C) in tropical and subtropical soils (Bayer et al. 2006; Veloso et al. 2018). Legume cover cropping [...]

Introduction The trophic transfer of highly nutritious lipids from phytoplankton to predators through small herbivores is essential for maintaining oceanic ecosystem dynamics (Lee et al., 2006). The calanoid copepods Calanus [...], Calanus finmarchicus and Calanus glacialis are keystone zooplankton species in North Atlantic and Arctic marine ecosystems because they form a link in the trophic transfer of nutritious lipids from phytoplankton to predators on higher trophic levels. These calanoid copepods spend several months of the year in deep waters in a dormant state called diapause, after which they emerge in surface waters to feed and reproduce during the spring phytoplankton bloom. Disruption of diapause timing could have dramatic consequences for marine ecosystems. In the present study, Calanus C5 copepodites were collected in a Norwegian fjord during diapause and were subsequently experimentally exposed to the water-soluble fraction of a naphthenic North Sea crude oil during diapause termination. The copepods were sampled repeatedly while progressing toward adulthood and were analyzed for utilization of lipid stores and for differential expression of genes involved in lipid metabolism. Our results indicate that water-soluble fraction exposure led to a temporary pause in lipid catabolism, suggested by (i) slower utilization of lipid stores in water-soluble fraction-exposed C5 copepodites and (ii) more genes in the [beta]-oxidation pathway being downregulated in water-soluble fraction-exposed C5 copepodites than in the control C5 copepodites. Because lipid content and/or composition may be an important trigger for termination of diapause, our results imply that the timing of diapause termination and subsequent migration to the surface may be delayed if copepods are exposed to oil pollution during diapause or diapause termination. This delay could have detrimental effects on ecosystem dynamics.

Introduction Inflammatory bowel disease (IBD), inclusive of Crohn's disease (CD) and ulcerative colitis (UC), is a chronic and relapsing inflammatory disorder of the gastrointestinal tract. IBD consists of a dysregulated [...], Cyclooxygenase 2 (Cox2) total knockout and myeloid knockout (MKO) mice develop Crohn's-like intestinal inflammation when fed cholate-containing high-fat diet (CCHF). We demonstrated that CCHF impaired intestinal barrier function and increased translocation of endotoxin, initiating TLR/MyD88-dependent inflammation in Cox2-KO but not WT mice. Cox2MKO increased proinflammatory mediators in LPS-activated macrophages, and in the intestinal tissue and plasma upon CCHF challenge. Cox2-MKO also reduced inflammation resolving lipoxin A4 (LXA4) in intestinal tissue, whereas administration of an LXA4 analog rescued disease in Cox2-MKO mice fed CCHF. The apolipoprotein A-I (APOA1) mimetic 4F mitigated disease in both the Cox2-MKO/CCHF and piroxicam-accelerated [Il10.sup.-/-] models of inflammatory bowel disease (IBD) and reduced elevated levels of proinflammatory mediators in tissue and plasma. APOA1 mimetic Tg6F therapy was also effective in reducing intestinal inflammation in the Cox2-MKO/CCHF model. We further demonstrated that APOA1 mimetic peptides (a) inhibited LPS and oxidized 1-palmitoyl-2-arachidonoyl-sn-phosphatidylcholine-dependent (oxPAPC-dependent) proinflammatory responses in human macrophages and intestinal epithelium, and (b) directly cleared proinflammatory lipids from mouse intestinal tissue and plasma. Our results support a causal role for proinflammatory and inflammation-resolving lipids in IBD pathology and a translational potential for APOA1 mimetic peptides for the treatment of IBD.

Lipid residues identified in Grooved Ware pottery from Durrington Walls have been interpreted as evidence for large-scale feasting associated with the construction of Stonehenge, around 2500 BC. While a function related to food consumption is possible, other explanations may be equally plausible. An alternative interpretation not previously considered is that these residues may be related to a non-food use of animal resources, such as in the production of tallow. Such an interpretation would support the 'greased sled' theory for the transport of the megaliths for Stonehenge. Keywords: Neolithic Britain, Durrington Walls, Stonehenge, lipid residues, Lipid residue analysis and pottery function The analysis of absorbed lipid residues is a well-established technique for determining the types of products processed in ceramic vessels. Research has focused largely [...]

The decline in physical activity (PA) from youth to young adulthood is evident, though limited research has addressed whether specific factors of K-12 physical education (PE) have any influence on outcomes during college years. This study examined the relationship between college students' physical fitness and PA behavior and their high school PE experiences. College student volunteers (n = 537) completed a fitness assessment examining aerobic endurance, muscular endurance, body composition, and blood glucose and lipids. A survey examined current PA and PE experience in high school (number of semesters, enjoyment, requirements). Analyses were conducted separately for males and females. Pearson correlations examined relationships between fitness, behavioral, and PE outcomes. Differences in behavioral and fitness outcomes were compared with t tests. The final sample was 56.6% male (n = 298) and 43.4% female (n = 227). For males, analyses revealed that PE enjoyment was significantly related to V[O.sub.2] max, curl-ups, and vigorous physical activity. Number of semesters of PE in high school was negatively associated with triglycerides and total cholesterol and positively associated with moderate physical activity. Those who took PE when it was not required were more vigorously active than those who did not. Males who had a waiver for PE had a lower body fat percentage, performed more curl-ups, and were more vigorously and moderately active compared with those who had no waiver. Number of semesters of PE in high school was negatively associated with triglycerides and total cholesterol. PE enjoyment was positively associated with V[O.sub.2] max and push-ups. For females, those who took PE when it wasn't required had a higher V[O.sub.2] max and vigorous physical activity compared with those who did not. Females with a waiver for PE class had higher triglycerides and total cholesterol compared with those who did not. Females in a coed PE class had a higher BMI and V[O.sub.2] max compared with those in a combination class. Effective PE programs that encourage participation and educate students on the benefits of physical activity have the capability to establish lifelong healthy and active habits that translate to the college years, and likely beyond. The main findings of this study have the potential to influence the policies regarding PE requirements for school-aged students in all states, such as possibly increasing PE requirements for all grades and discovering certain aspects of PE that could make it more enjoyable for a larger number of students., Physical education (PE) in schools is a cornerstone in the development of early physical activity (PA) habits, gross motor and movement skills, and personal and social character development in children [...]

Introduction Pulmonary surfactant is a complex mixture of lipids and associated proteins synthesized by alveolar type 2 (AT2) cells in the peripheral lung. Surfactant is required at birth and throughout [...], Adaptation to respiration at birth depends upon the synthesis of pulmonary surfactant, a lipid-protein complex that reduces surface tension at the air-liquid interface in the alveoli and prevents lung collapse during the ventilatory cycle. Herein, we demonstrated that the gene encoding a subunit of the endoplasmic reticulum membrane complex, EMC3, also known as TMEM111 (Emc3/Tmem111), was required for murine pulmonary surfactant synthesis and lung function at birth. Conditional deletion of Emc3 in murine embryonic lung epithelial cells disrupted the synthesis and packaging of surfactant lipids and proteins, impaired the formation of lamellar bodies, and induced the unfolded protein response in alveolar type 2 (AT2) cells. EMC3 was essential for the processing and routing of surfactant proteins, SP-B and SP-C, and the biogenesis of the phospholipid transport protein ABCA3. Transcriptomic, lipidomic, and proteomic analyses demonstrated that EMC3 coordinates the assembly of lipids and proteins in AT2 cells that is necessary for surfactant synthesis and function at birth.