scholarly journals Perspectives on marine zooplankton lipids

2007 ◽  
Vol 64 (11) ◽  
pp. 1628-1639 ◽  
Author(s):  
G Kattner ◽  
W Hagen ◽  
R F Lee ◽  
R Campbell ◽  
D Deibel ◽  
...  
Keyword(s):  
Food Web ◽  
Trophic Levels ◽  
Future Research ◽  
Ocean Climate ◽  
Marine Food Web ◽  
Storage Lipids ◽  
Marine Zooplankton ◽  
Lipid Dynamics ◽  
And Function

We developed new perspectives to identify important questions and to propose approaches for future research on marine food web lipids. They were related to (i) structure and function of lipids, (ii) lipid changes during critical life phases, (iii) trophic marker lipids, and (iv) potential impact of climate change. The first addresses the role of lipids in membranes, storage lipids, and buoyancy with the following key question: How are the properties of membranes and deposits affected by the various types of lipids? The second deals with the importance of various types of lipids during reproduction, development, and resting phases and addresses the role of the different storage lipids during growth and dormancy. The third relates to trophic marker lipids, which are an important tool to follow lipid and energy transfer through the food web. The central question is how can fatty acids be used to identify and quantify food web relationships? With the fourth, hypotheses are presented on effects of global warming, which may result in the reduction or change in abundance of large, lipid-rich copepods in polar oceans, thereby strongly affecting higher trophic levels. The key question is how will lipid dynamics respond to changes in ocean climate at high latitudes?

scholarly journals Antioxidant and Signaling Role of Plastid-Derived Isoprenoid Quinones and Chromanols

2021 ◽  
Vol 22 (6) ◽  
pp. 2950
Author(s):  
Beatrycze Nowicka ◽  
Agnieszka Trela-Makowej ◽  
Dariusz Latowski ◽  
Kazimierz Strzalka ◽  
Renata Szymańska
Keyword(s):  
Current Knowledge ◽  
Stress Factors ◽  
Oxygenic Photosynthesis ◽  
Ros Generation ◽  
Main Site ◽  
Storage Lipids ◽  
Abiotic Stress Factors ◽  
Cell Components ◽  
And Function

Plant prenyllipids, especially isoprenoid chromanols and quinols, are very efficient low-molecular-weight lipophilic antioxidants, protecting membranes and storage lipids from reactive oxygen species (ROS). ROS are byproducts of aerobic metabolism that can damage cell components, they are also known to play a role in signaling. Plants are particularly prone to oxidative damage because oxygenic photosynthesis results in O2 formation in their green tissues. In addition, the photosynthetic electron transfer chain is an important source of ROS. Therefore, chloroplasts are the main site of ROS generation in plant cells during the light reactions of photosynthesis, and plastidic antioxidants are crucial to prevent oxidative stress, which occurs when plants are exposed to various types of stress factors, both biotic and abiotic. The increase in antioxidant content during stress acclimation is a common phenomenon. In the present review, we describe the mechanisms of ROS (singlet oxygen, superoxide, hydrogen peroxide and hydroxyl radical) production in chloroplasts in general and during exposure to abiotic stress factors, such as high light, low temperature, drought and salinity. We highlight the dual role of their presence: negative (i.e., lipid peroxidation, pigment and protein oxidation) and positive (i.e., contribution in redox-based physiological processes). Then we provide a summary of current knowledge concerning plastidic prenyllipid antioxidants belonging to isoprenoid chromanols and quinols, as well as their structure, occurrence, biosynthesis and function both in ROS detoxification and signaling.

The Role of Ammonites in the Mesozoic Marine Food Web Revealed by Jaw Preservation

Science ◽  
2011 ◽  
Vol 331 (6013) ◽  
pp. 70-72 ◽  
Author(s):  
I. Kruta ◽  
N. Landman ◽  
I. Rouget ◽  
F. Cecca ◽  
P. Tafforeau
Keyword(s):  
Food Web ◽  
Marine Food Web ◽  
Marine Food

scholarly journals Using Tertiary Sulci to Map the “Cognitive Globe” of Prefrontal Cortex

2021 ◽  
pp. 1-18
Author(s):  
Jacob A. Miller ◽  
Mark D'Esposito ◽  
Kevin S. Weiner
Keyword(s):  
Prefrontal Cortex ◽  
Frontal Lobe ◽  
Spatial Scales ◽  
Structure And Function ◽  
Future Research ◽  
Functional Relationships ◽  
Theoretical Perspectives ◽  
Individual Participant ◽  
And Function

Stuss considered the human prefrontal cortex (pFC) as a “cognitive globe” [Stuss, D. T., & Benson, D. F. Neuropsychological studies of the frontal lobes. Psychological Bulletin, 95, 3–28, 1984] on which functions of the frontal lobe could be mapped. Here, we discuss classic and recent findings regarding the evolution, development, function, and cognitive role of shallow indentations or tertiary sulci in pFC, with the goal of using tertiary sulci to map the “cognitive globe” of pFC. First, we discuss lateral pFC (LPFC) tertiary sulci in classical anatomy and modern neuroimaging, as well as their development, with a focus on those within the middle frontal gyrus. Second, we discuss tertiary sulci in comparative neuroanatomy, focusing on primates. Third, we summarize recent findings showing the utility of tertiary sulci for understanding structural–functional relationships with functional network insights in ventromedial pFC and LPFC. Fourth, we revisit and update unresolved theoretical perspectives considered by C. Vogt and O. Vogt (Allgemeinere ergebnisse unserer hirnforschung. Journal für Psychologie und Neurologie, 25, 279–462, 1919) and F. Sanides (Structure and function of the human frontal lobe. Neuropsychologia, 2, 209–219, 1964) that tertiary sulci serve as landmarks for cortical gradients. Together, the consideration of these classic and recent findings indicate that tertiary sulci are situated in a unique position within the complexity of the “cognitive globe” of pFC: They are the smallest and shallowest of sulci in pFC, yet can offer insights that bridge spatial scales (microns to networks), modalities (functional connectivity to behavior), and species. As such, the map of tertiary sulci within each individual participant serves as a coordinate system specific to that individual on which functions may be further mapped. We conclude with new theoretical and methodological questions that, if answered in future research, will likely lead to mechanistic insight regarding the structure and function of human LPFC.

scholarly journals Trophodynamics of nekton assemblages and relationships with estuarine habitat structure across a subtropical estuary

2018 ◽  
Author(s):  
Shannon D Whaley ◽  
James J Burd ◽  
Craig W. Harmak ◽  
Colin P Shea
Keyword(s):  
Gulf Of Mexico ◽  
Food Web ◽  
Trophic Levels ◽  
Spatial Gradient ◽  
Seagrass Beds ◽  
Charlotte Harbor ◽  
Wading Birds ◽  
Benthic Production ◽  
Important Time ◽  
And Function

Understanding trophodynamics of estuarine and marine ecosystems is important in developing food-web models prevalent in ecosystem-based approaches to fisheries management, as well as assessing ecosystem condition and function. Few studies have examined seasonal and spatial trophodynamics of nekton assemblages in shallow subtropical waters on estuary-wide spatial extent. We used fisheries-independent monitoring data to examine the spatial distribution and seasonal trophodynamics of nekton assemblages in shallow waters (≤ 1.5m) of Charlotte Harbor, Florida, USA, as well as the lower Peace and Myakka Rivers. Overall nekton densities were generally high in spring (April - May), especially in the lower rivers, and declined through the summer (June – October), and fall (November – December), with small increases in mean nekton densities in winter (January – March). We found that species composition as well as trophic structure of nekton assemblages changed along a broad spatial gradient from the lower portions of the Peace and Myakka Rivers to lower Charlotte Harbor near the passes to the Gulf of Mexico. Nekton assemblages dominated by planktonic-feeding species were located in lower Peace and Myakka Rivers and extended into upper Charlotte Harbor in apparent response to seasonal fluctuations in freshwater inflow. In contrast, most of the nekton assemblages within Charlotte Harbor proper were dominated by nekton species feeding within the benthos (those feeding on benthic infauna, epifauna, seagrass, and/or detritus) throughout the year. The proportion of benthic feeders was positively correlated with landscape metrics describing the area of continuous seagrass beds mapped from aerial photography, and negatively correlated with distance to the nearest pass to the Gulf of Mexico. These relationships were consistent throughout all four seasons of the year. The proportion of benthic feeders varied seasonally, and was relatively high in the fall and winter compared with the spring and summer. The predominance of benthic feeding species during fall and winter when overall nekton densities were low, suggests that benthic production is an important in supporting populations of forage fishes for higher trophic levels, such as piscivorous fishes and wading birds during this time of year. This is an important time for overwintering wading birds, as well as several economically-important fishery species who are recruiting into shallow water areas of Charlotte Harbor. Planktonic production is often the focus of food-web models with benthic production sometimes not included. We found both planktonic and benthic production to be important in Charlotte Harbor. Therefore, both sources of production need to be included in food-web models for Charlotte Harbor, as well as similar subtropical estuaries with relatively large areas of seagrass beds.

scholarly journals Evolution of the visual cycle: the role of retinoid-binding proteins

2002 ◽  
Vol 175 (1) ◽  
pp. 75-88 ◽  
Author(s):  
F Gonzalez-Fernandez
Keyword(s):  
Binding Proteins ◽  
Binding Protein ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Future Research ◽  
Visual Cycle ◽  
Hormone Binding ◽  
Evolutionary Context ◽  
And Function

The trafficking of retinoids in the retina represents a model to study soluble hormone-binding proteins in a complex system subject to profound evolutionary adaptations. Although a remarkable illustration of convergent evolution, all visual systems detect light in the same way, that is through the photoisomerization of an 11-cis retinoid to a corresponding trans isomer. What is strikingly different between the systems, is the mechanism by which the 11-cis chromophore is reformed and visual pigment regenerated in a process known as the visual cycle. The variations of the cycle address a problem inherent to retinoids themselves. That is, the properties that make these molecules suited for light detection also account for their susceptibility to oxidative and isomeric degradation, and cellular toxicity. The cycle therefore provides an opportunity to examine the role of soluble hormone-binding proteins within an integrative and evolutionary context. The present review focuses on interphotoreceptor retinoid-binding protein (IRBP), a controversial glycolipoprotein that recruits a protein fold common to Cterminal-processing proteases and the crotonase family. This unorthodox retinoid-binding protein is entrapped in the subretinal compartment of those eyes that translocate visual cycle retinoids between the photoreceptors and the retinal pigment epithelium. Recent studies suggest that we should look beyond a strictly carrier function if we are to appreciate the role of IRBP in the visual cycle. Here we draw lessons from other soluble hormone-binding proteins to anticipate avenues of future research likely to provide insight into the structure and function of IRBP in vision.

scholarly journals Novel Insight Into the Development and Function of Hypopharyngeal Glands in Honey Bees

2021 ◽  
Vol 11 ◽  
Author(s):  
Saboor Ahmad ◽  
Shahmshad Ahmed Khan ◽  
Khalid Ali Khan ◽  
Jianke Li
Keyword(s):  
Honey Bees ◽  
Future Research ◽  
Factors Affecting ◽  
Hypopharyngeal Glands ◽  
And Function ◽  
First Time ◽  
The Brain ◽  
Insight Into ◽  
Made In

Hypopharyngeal glands (HGs) are the most important organ of hymenopterans which play critical roles for the insect physiology. In honey bees, HGs are paired structures located bilaterally in the head, in front of the brain between compound eyes. Each gland is composed of thousands of secretory units connecting to secretory duct in worker bees. To better understand the recent progress made in understanding the structure and function of these glands, we here review the ontogeny of HGs, and the factors affecting the morphology, physiology, and molecular basis of the functionality of the glands. We also review the morphogenesis of HGs in the pupal and adult stages, and the secretory role of the glands across the ages for the first time. Furthermore, recent transcriptome, proteome, and phosphoproteome analyses have elucidated the potential mechanisms driving the HGs development and functionality. This adds a comprehensive novel knowledge of the development and physiology of HGs in honey bees over time, which may be helpful for future research investigations.

scholarly journals Using tertiary sulci to map the “cognitive globe” of prefrontal cortex

2020 ◽  
Author(s):  
Jacob Miller ◽  
Mark D'Esposito ◽  
kevin weiner
Keyword(s):  
Prefrontal Cortex ◽  
Spatial Scales ◽  
Future Research ◽  
Comparative Neuroanatomy ◽  
Functional Relationships ◽  
Mechanistic Insight ◽  
Theoretical Perspectives ◽  
Individual Participant ◽  
And Function

Stuss (1984) considered the human prefrontal cortex (PFC) as a “cognitive globe” on which functions of the frontal lobe could be mapped. Here, we discuss classic and recent findings regarding the evolution, development, function, and cognitive role of shallow indentations, or tertiary sulci, in PFC with the goal of using tertiary sulci to map the “cognitive globe” of PFC. First, we discuss lateral PFC (LPFC) tertiary sulci in classical anatomy and modern neuroimaging, as well as their development, with a focus on those within the middle frontal gyrus (MFG). Second, we discuss tertiary sulci in comparative neuroanatomy, focusing on primates. Third, we summarize recent findings showing the utility of tertiary sulci for understanding structural-functional relationships with functional network insights in ventromedial and LPFC. Fourth, we revisit and update unresolved theoretical perspectives considered by Vogt and Vogt (1919) and Sanides (1964) that tertiary sulci serve as landmarks for cortical gradients. Together, the consideration of these classic and recent findings indicate that tertiary sulci are situated in a unique position within the complexity of the “cognitive globe” of PFC: they are the smallest and shallowest of sulci in PFC, yet can offer insights that bridge spatial scales (microns to networks), modalities (functional connectivity to behavior), and species. As such, the map of tertiary sulci within each individual participant serves as a coordinate system specific to that individual on which functions may be further mapped. We conclude with new theoretical and methodological questions that if answered in future research, will likely lead to mechanistic insight regarding the structure and function of human LPFC.

scholarly journals Is Extreme in the Eye of the Beholder? An Experimental Assessment of Extremist Cognitions

2020 ◽  
pp. 088626052095864
Author(s):  
Neil Shortland ◽  
Elias Nader ◽  
Lisa Thompson ◽  
Marek Palasinski
Keyword(s):  
Future Research ◽  
Personality Factors ◽  
Psychological Consequences ◽  
Research Directions ◽  
Personality Differences ◽  
Form And Function ◽  
Individual Personality ◽  
Future Research Directions ◽  
And Function

Scholars have extensively discussed the topic of “online radicalization,” often seeking to understand the form and function of online extremist material. However, this work has neglected to examine the role that the Internet plays alongside individual personality factors in the process through which someone develops violent extremist cognitions. This article aims to extend the understanding of the role of personality differences in the effect of exposure to extremist material online. In this study, we experimentally measure the short-term psychological consequences of exposure to extremist material on extremist cognitions. We use a between-group experimental design in which participants are shown extremist propaganda with either pre- or post-counter messages. Our results indicate that trait personality, and specifically aggression, may be more influential than exposure to extremist propaganda in influencing extremist cognitions. We discuss the implications of these results in the context of future research directions.

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