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Hormones and Behavior Nov 2021Individuals that live in groups experience different challenges based on their social rank and sex. Glucocorticoids have a well-established role in coordinating...
Individuals that live in groups experience different challenges based on their social rank and sex. Glucocorticoids have a well-established role in coordinating responses to challenges and glucocorticoid levels often vary between ranks and sexes. However, the neuroendocrine mechanisms regulating glucocorticoid dynamics in wild groups are poorly understood, making it difficult to determine the functional consequences of differences in glucocorticoid levels. Therefore, we observed wild social groups of a cooperatively breeding fish (Neolamprologus pulcher) and evaluated how scale cortisol content (an emerging method to evaluate cortisol dynamics in fishes) and expression of glucocorticoid-related genes varied across group members. Scale cortisol was detectable in ~50% of dominant males (7/17) and females (7/15)-but not in any subordinates (0/16)-suggesting that glucocorticoid levels were higher in dominants. However, the apparent behavioural and neuroendocrine factors regulating cortisol levels varied between dominant sexes. In dominant females, higher cortisol was associated with greater rates of territory defense and increased expression of corticotropin-releasing factor in the preoptic and hypothalamic regions of the brain, but these patterns were not observed in dominant males. Additionally, transcriptional differences in the liver suggest that dominant sexes may use different mechanisms to cope with elevated cortisol levels. While dominant females appeared to reduce the relative sensitivity of their liver to cortisol (fewer corticosteroid receptor transcripts), dominant males appeared to increase hepatic cortisol breakdown (more catabolic enzyme transcripts). Overall, our results offer valuable insights on the mechanisms regulating rank- and sex-based glucocorticoid dynamics, as well as the potential functional outcomes of these differences.
Topics: Animals; Cichlids; Corticotropin-Releasing Hormone; Female; Glucocorticoids; Hydrocortisone; Male; Sex Characteristics
PubMed: 34717080
DOI: 10.1016/j.yhbeh.2021.105079 -
3 Biotech May 2021Coastal sand dunes (CSDs), unique, stressed and hostile habitats act as a barrier between marine and terrestrial ecosystems. CSDs are stressed in terms of nutrition and...
UNLABELLED
Coastal sand dunes (CSDs), unique, stressed and hostile habitats act as a barrier between marine and terrestrial ecosystems. CSDs are stressed in terms of nutrition and fluctuating physio-chemical conditions. CSD is classified into several types, each of which presents different challenges for life forms. This study focuses on exploring bacterial and archaeal diversity and community structure in four CSD namely, Embryo, Fore, Gray, and Mature dunes of Keri beach, Goa along the west coast of India. The study was carried out using Next Generation Sequencing of hypervariable V3-V4 regions of the 16S rRNA gene using Illumina HiSeq platform. The present study hypothesizes that the prokaryotic communities at each dune may be different and could have different role in the ecosystem. The NGS for Embryo, Fore, Gray, and Mature dunes gave 1,045,447, 1,451,753, 1,321,867, and 1,537,758 paired-end reads, respectively, out of which 54,500, 50,032, 37,819, and 111,186 were retained through various quality filtrations. A total of 74, 63, 65, and 65% of OTUs, respectively, remained unknown at the species level. The highest bacterial and archaeal abundance was reported from Mature and Embryo dunes, respectively. Phylum Actinobacteria dominated the Embryo, Fore, and Mature dunes, whereas phylum Proteobacteria was the dominant in the Gray dune. was predominant in overall CSD followed by and . The commonly and exclusively found members in each dune are cataloged. The highest species dominance, diversity, species richness, and abundance were observed in Embryo, Fore, Gray, and Mature dunes, respectively. The present study clearly elucidates that each dune has a distinct microbial community structure.
SUPPLEMENTARY INFORMATION
The online version contains supplementary material available at 10.1007/s13205-021-02809-5.
PubMed: 33968595
DOI: 10.1007/s13205-021-02809-5 -
Heliyon May 2021This study is a meta-analysis of empirical studies in social media strategies and reputation research. The research goal is to give a clearer idea of the broad... (Review)
Review
This study is a meta-analysis of empirical studies in social media strategies and reputation research. The research goal is to give a clearer idea of the broad directions and paradigm shifts in Twitter usage discourse over the years. Its major goal is to examine thematic trends, theoretical framework and methodology that have characterized the discourse. Sixty relevant articles were identified, coded and content-analyzed. Findings revealed that dominant themes include stakeholder perceptions of communication strategies, social network sites, dynamics of global pandemic (i.e Covid-19 pandemic) and corporate reputation. Also, experiment, case study and survey are the dominant research methods that characterize research in this discourse. Findings also revealed large domination of the Situational Crisis Communication Theory (SCCT) and the Image Repair Theory. However, research in this area lacks significant empirical evidence from Africa and Nigeria in particular, where the global pandemic seems to be a recurring phenomenon. The majority of the reviewed journal articles were conducted in the Western clime, with little attention on Africa. Scholarship needs to move beyond this point to provide a holistic and balanced view on the crisis by exploring cases in Africa and particularly, in Nigeria. This gap will provide an opportunity for understanding the global pandemic (i.e. Covid-19) dynamics in Africa and will further determine whether findings can be consistent across the world.
PubMed: 34041378
DOI: 10.1016/j.heliyon.2021.e06920 -
AoB PLANTS Oct 2023may be considered the tree of the Mediterranean Basin, dominating coastal forest areas up to 2000 m above sea level at some sites. However, an increase in holm oak... (Review)
Review
may be considered the tree of the Mediterranean Basin, dominating coastal forest areas up to 2000 m above sea level at some sites. However, an increase in holm oak decline has been observed in the last decade. In this review, we analysed the current literature to answer the following questions: what are the traits that allow holm oak to thrive in the Mediterranean environment, and what are the main factors that are currently weakening this species? In this framework, we attempt to answer these questions by proposing a triangle as a graphical summary. The first vertex focuses on the main morpho-anatomical, biochemical and physiological traits that allow holm oak to dominate Mediterranean forests. The other two vertices consider abiotic and biotic stressors that are closely related to holm oak decline. Here, we discuss the current evidence of holm oak responses to abiotic and biotic stresses and propose a possible solution to its decline through adequate forest management choices, thus allowing the species to maintain its ecological domain.
PubMed: 37899973
DOI: 10.1093/aobpla/plad051 -
Ecology and Evolution Dec 2021Biotic and abiotic factors interact with dominant plants-the locally most frequent or with the largest coverage-and nondominant plants differently, partially because...
Biotic and abiotic factors interact with dominant plants-the locally most frequent or with the largest coverage-and nondominant plants differently, partially because dominant plants modify the environment where nondominant plants grow. For instance, if dominant plants compete strongly, they will deplete most resources, forcing nondominant plants into a narrower niche space. Conversely, if dominant plants are constrained by the environment, they might not exhaust available resources but instead may ameliorate environmental stressors that usually limit nondominants. Hence, the nature of interactions among nondominant species could be modified by dominant species. Furthermore, these differences could translate into a disparity in the phylogenetic relatedness among dominants compared to the relatedness among nondominants. By estimating phylogenetic dispersion in 78 grasslands across five continents, we found that dominant species were clustered (e.g., co-dominant grasses), suggesting dominant species are likely organized by environmental filtering, and that nondominant species were either randomly assembled or overdispersed. Traits showed similar trends for those sites (<50%) with sufficient trait data. Furthermore, several lineages scattered in the phylogeny had more nondominant species than expected at random, suggesting that traits common in nondominants are phylogenetically conserved and have evolved multiple times. We also explored environmental drivers of the dominant/nondominant disparity. We found different assembly patterns for dominants and nondominants, consistent with asymmetries in assembly mechanisms. Among the different postulated mechanisms, our results suggest two complementary hypotheses seldom explored: (1) Nondominant species include lineages adapted to thrive in the environment generated by dominant species. (2) Even when dominant species reduce resources to nondominant ones, dominant species could have a stronger positive effect on some nondominants by ameliorating environmental stressors affecting them, than by depleting resources and increasing the environmental stress to those nondominants. These results show that the dominant/nondominant asymmetry has ecological and evolutionary consequences fundamental to understand plant communities.
PubMed: 35003636
DOI: 10.1002/ece3.8266 -
Current Biology : CB Aug 2022Animals often display prosocial behaviors, performing actions that benefit others. Although prosociality is essential for social bonding and cooperation, we still know...
Animals often display prosocial behaviors, performing actions that benefit others. Although prosociality is essential for social bonding and cooperation, we still know little about how animals integrate behavioral cues from those in need to make decisions that increase their well-being. To address this question, we used a two-choice task where rats can provide rewards to a conspecific in the absence of self-benefit and investigated which conditions promote prosociality by manipulating the social context of the interacting animals. Although sex or degree of familiarity did not affect prosocial choices in rats, social hierarchy revealed to be a potent modulator, with dominant decision-makers showing faster emergence and higher levels of prosocial choices toward their submissive cage mates. Leveraging quantitative analysis of multimodal social dynamics prior to choice, we identified that pairs with dominant decision-makers exhibited more proximal interactions. Interestingly, these closer interactions were driven by submissive animals that modulated their position and movement following their dominants and whose 50-kHz vocalization rate correlated with dominants' prosociality. Moreover, Granger causality revealed stronger bidirectional influences in pairs with dominant focals and submissive recipients, indicating increased behavioral coordination. Finally, multivariate analysis highlighted body language as the main information dominants use on a trial-by-trial basis to learn that their actions have effects on others. Our results provide a refined understanding of the behavioral dynamics that rats use for action-selection upon perception of socially relevant cues and navigate social decision-making.
Topics: Altruism; Animals; Cues; Hierarchy, Social; Rats; Reward; Social Behavior
PubMed: 35803272
DOI: 10.1016/j.cub.2022.06.026 -
RSC Advances Jul 2022Zinc plays a vital role in structural, catalysis, and signal regulation in the human body. Zinc deficiency leads to the dysfunction of many organs and immunity systems....
Zinc plays a vital role in structural, catalysis, and signal regulation in the human body. Zinc deficiency leads to the dysfunction of many organs and immunity systems. Diet proteins have distinct effects on zinc uptake. However, the mechanisms are uncovered. Here we select three principal components from whey protein: alpha-lactalbumin, beta-lactoglobulin, and bovine serum albumin, which bind with zinc at different affinities, to evaluate the relationship between their potential zinc uptake and protein binding. The experimental data shows that beta-lactoglobulin could promote zinc uptake, alpha-lactalbumin has minor effects, whereas bovine serum albumin reduced zinc uptake in Caco-2 cell lines. Zinc binding effects on protein structure were thoroughly inspected through fluorescent spectroscopy and X-ray crystallography. Isothermal titration calorimetry revealed that three proteins have different binding affinities toward zinc ions. We speculate that protein binding eliminates toxic effects from free zinc, and the binding strength dominates zinc uptake.
PubMed: 35975046
DOI: 10.1039/d2ra03565k -
Cureus Jun 2023Background The aim of this study is to determine ocular dominance and its association with central corneal thickness (CCT). These two parameters are of great...
Background The aim of this study is to determine ocular dominance and its association with central corneal thickness (CCT). These two parameters are of great significance in clinical practice; identifying the dominant eye helps in planning cataract surgeries, treatment of presbyopia, monovision correction, etc., and assessing the CCT helps in early diagnosis and management of keratoconus, glaucoma, contact lens-related complications, and dry eye. Methods A cross-sectional study that involves patients and volunteers who have come for a checkup to the ophthalmology department of the college hospital. Ninety patients were examined for this study within two months. The hole-in-card test is performed to determine the ocular dominance in people with normal and healthy eyes without any pathologies except refractive errors. Specular microscopy through a non-contact modality will be done to assess the thickness of the central cornea in both eyes. Statistical analysis was done using the paired t-test to compare the patient's eyes and the chi-square test, which helps us associate ocular dominance and CCT. Results Right eye dominance was seen in the majority of the participants (72.91%), whereas left eye dominance was seen in comparatively fewer participants (27.08%). The CCT of the dominant eye is found to be 520.40 ± 29.83 μm and that of the non-dominant eye is 524.40 ± 29.37 μm. A lower CCT in the dominant eye was seen in 83.33% of the subjects; 14.58% of them had a higher CCT in the dominant eye and 2.08% had the same CCT in both eyes. Conclusion From the observational study that has been made, the majority of the population shows right eye dominance. The CCT is relatively thinner in the dominant eye. About 80-85% of the examined people showed a thinner cornea in the dominant eye. But we cannot generalize that the eye with a lesser corneal thickness will be the dominant eye in all the cases, as a few cases have shown dominance in the eye with a thicker cornea.
PubMed: 37519501
DOI: 10.7759/cureus.41033 -
Nature Communications Oct 2023In most of the world, conditions conducive to wildfires are becoming more prevalent. Net carbon emissions from wildfires contribute to a positive climate feedback that...
In most of the world, conditions conducive to wildfires are becoming more prevalent. Net carbon emissions from wildfires contribute to a positive climate feedback that needs to be monitored, quantified, and predicted. Here we use a causal inference approach to evaluate the influence of top-down weather and bottom-up fuel precursors on wildfires. The top-down dominance on wildfires is more widespread than bottom-up dominance, accounting for 73.3% and 26.7% of regions, respectively. The top-down precursors dominate in the tropical rainforests, mid-latitudes, and eastern Siberian boreal forests. The bottom-up precursors dominate in North American and European boreal forests, and African and Australian savannahs. Our study identifies areas where wildfires are governed by fuel conditions and hence where fuel management practices may be more effective. Moreover, our study also highlights that top-down and bottom-up precursors show complementary wildfire predictability across timescales. Seasonal or interannual predictions are feasible in regions where bottom-up precursors dominate.
PubMed: 37884516
DOI: 10.1038/s41467-023-42597-5 -
Scientific Reports Dec 2022We assessed the fungal and fungal-like sequence diversity present in marine sediments obtained in the vicinity of the South Shetland Islands (Southern Ocean) using DNA...
We assessed the fungal and fungal-like sequence diversity present in marine sediments obtained in the vicinity of the South Shetland Islands (Southern Ocean) using DNA metabarcoding through high-throughput sequencing (HTS). A total of 193,436 DNA reads were detected in sediment obtained from three locations: Walker Bay (Livingston Island) at 52 m depth (48,112 reads), Whalers Bay (Deception Island) at 151 m (104,704) and English Strait at 404 m (40,620). The DNA sequence reads were assigned to 133 distinct fungal amplicon sequence variants (ASVs) representing the phyla Ascomycota, Basidiomycota, Mortierellomycota, Chytridiomycota, Glomeromycota, Monoblepharomycota, Mucoromycota and Rozellomycota and the fungal-like Straminopila. Thelebolus balaustiformis, Pseudogymnoascus sp., Fungi sp. 1, Ciliophora sp., Agaricomycetes sp. and Chaetoceros sp. were the dominant assigned taxa. Thirty-eight fungal ASVs could only be assigned to higher taxonomic levels, and may represent taxa not currently included in the available databases or represent new taxa and/or new records for Antarctica. The total fungal community displayed high indices of diversity, richness and moderate to low dominance. However, diversity and taxa distribution varied across the three sampling sites. In Walker Bay, unidentified fungi were dominant in the sequence assemblage. Whalers Bay sediment was dominated by Antarctic endemic and cold-adapted taxa. Sediment from English Strait was dominated by Ciliophora sp. and Chaetoceros sp. These fungal assemblages were dominated by saprotrophic, plant and animal pathogenic and symbiotic taxa. The detection of an apparently rich and diverse fungal community in these marine sediments reinforces the need for further studies to characterize their richness, functional ecology and potential biotechnological applications.
Topics: DNA Barcoding, Taxonomic; Antarctic Regions; Biotechnology; Ecology; DNA
PubMed: 36473886
DOI: 10.1038/s41598-022-25310-2