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Background: Antiplatelet agents have been shown to worsen outcomes following traumatic injury. Research on desmopressin (DDAVP) and platelet transfusion for antiplatelet reversal is limited. We aimed to evaluate the effect of these agents on patients taking pre-injury antiplatelet medications who experienced traumatic brain injury (TBI) after blunt trauma. Methods: This is a retrospective cohort study of adult trauma patients from 2014 to 2021 on aspirin and/or a P2Y12 inhibitor. Patients were stratified into groups based on if they received DDAVP, platelets, both agents, or neither. Results: Of 5525 included patients, 4696 (85.4%) were not reversed, 461 (8.4%) received platelets, 173 (3.1%) received DDAVP, and 172 (3.1%) received both reversals. There was no statistically significant difference in length of stay between, but patients who received platelets or both reversals were more likely to have hospital complications (p < 0.05), longer hospital length of stay (p < 0.001), and longer ICU length of stay (p < 0.001) compared to those who did not receive reversal. A subgroup analysis of patients with a head AIS of 4 or 5 confirmed these findings. Conclusions: Patients who received platelets or both reversals had a longer length of hospital stay and length of ICU stay. It is difficult to recommend one treatment over another based on our results alone. Further studies are needed to help clarify the risks and benefits of reversal agents in this patient population. [ABSTRACT FROM AUTHOR]

Background: Thomboelastography (TEG) is a point of care viscoelastic test that provides an assessment of clot formation and kinetics. Antiplatelet agents are commonly used but there is limited literature evaluating their possible effects on overall clot kinetics. We aimed to evaluate the relationship between antiplatelet agents and clot kinetics as defined by TEG. Methods: This is a retrospective study of adult patients who underwent TEG from February 2018 to July 2020. Patients who received anticoagulants or blood transfusions within 72 hours, had an incomplete TEG, were diagnosed with COVID-19, or had liver failure were excluded. Patients were stratified based on antiplatelet status. Results: Of 1060 patients, 119 were included (50 controls, 69 antiplatelet agents—37 aspirin monotherapy, 26 dual antiplatelet therapy). Between the control and antiplatelet therapy groups, there was no significant difference in clot time, maximal clot strength, or fibrinogen level. When compared to control patients, patients on dual antiplatelets had significantly higher fibrinogen levels (408.1 mg/dL vs 481.5 mg/dL, P =.013) but no significant differences in clot time or maximal clot strength. In our subgroup analysis, patients on dual antiplatelets had increased maximal clot strength (58.8° vs 63°, P =.005) and fibrinogen levels (384.1 mg/dL vs 481.5 mg/dL, P =.005) compared to those on aspirin alone. Discussion: Compared to control patients and those on aspirin alone, patients on dual antiplatelets have increased maximal clot strength and increased fibrinogen levels. These results can help physicians better target product resuscitation in patients who are on antiplatelet agents. [ABSTRACT FROM AUTHOR]

Background: Alvimopan is a µ-opioid receptor antagonist associated with shorter time to gastrointestinal recovery in patients having open colorectal surgery. Data demonstrating the benefit of perioperative alvimopan for the minimally invasive surgical approach are inconsistent. The aim of this study is to determine colorectal surgery groups that benefit from perioperative alvimopan. Methods: This is a retrospective cohort analysis of colorectal surgery patients who had, and patients who did not have, perioperative alvimopan in the Michigan Surgical Quality Collaborative regional risk-adjusted database from 2018 through 2021. Main outcome measures were postoperative length of hospital stay, time to return of bowel function, and postoperative ileus. Results: There were 10,010 patients (30.3% open, 40.5% laparoscopic, 12.7% hand-assist laparoscopic, 43.5% robotic) who met inclusion criteria—4919 received alvimopan in the perioperative period and 5091 did not. When compared to those not receiving alvimopan, unadjusted outcomes showed that the alvimopan group had significantly shorter postoperative length of stay (4.75 days vs 5.5 days, p < 0.001), shorter time to return of bowel function (1.61 days vs 2.01 days, p < 0.001) and less postoperative ileus (5.45% vs 7.94%, p < 0.001). After adjustment, regression models confirmed that alvimopan was associated with an 9.6% reduction in hospital length of stay (p < 0.001), a 14.9% shorter time to return of bowel function (p < 0.001), and a 42.1% reduction in postoperative ileus (p < 0.001). Subgroup analysis showed significant benefit of alvimopan for all three outcomes in patients having the minimally invasive approach. Conclusions: Alvimopan is associated with shorter hospital length of stay, shorter time to return of bowel function, and decreased postoperative ileus when administered to patients undergoing colorectal surgery. Benefit is not limited to the open approach and includes minimally invasive laparoscopic and robotic colorectal procedures. [ABSTRACT FROM AUTHOR]

The analysis of phylogeographic patterns has often been based on mitochondrial DNA variation, but recent analyses dealing with nuclear DNA have in some instances revealed mito-nuclear discordances and complex evolutionary histories. These enigmatic scenarios, which may involve stochastic lineage sorting, ancestral hybridization, past dispersal and secondary contacts, are increasingly scrutinized with a new generation of genomic tools such as RADseq, which also poses additional analytical challenges. Here, we revisited the previously inconclusive phylogeographic history, showing the mito-nuclear discordance of an endemic groundwater amphipod from Iceland, Crangonyx islandicus, which is the only metazoan known to have survived the Pleistocene beneath the glaciers. Previous studies based on three DNA markers documented a mitochondrial scenario with the main divergence occurring between populations in northern Iceland and an ITS scenario with the main divergence between the south and north. We used double digest restriction-site-associated DNA sequencing (ddRADseq) to clarify this mito-nuclear discordance by applying several statistical methods while estimating the sensitivity to different analytical approaches (data-type, differentiation indices and base call uncertainty). A majority of nuclear markers and methods support the ITS divergence. Nevertheless, a more complex scenario emerges, possibly involving introgression led by male-biased dispersal among northern locations or mitochondrial capture, which may have been further strengthened by natural selection. [ABSTRACT FROM AUTHOR]

Background: Whole genomes are commonly assembled into a collection of scaffolds and often lack annotations of autosomes, sex chromosomes, and organelle genomes (i.e., mitochondrial and chloroplast). As these chromosome types differ in effective population size and can have highly disparate evolutionary histories, it is imperative to take this information into account when analysing genomic variation. Here we assessed the accuracy of four methods for identifying the homogametic sex chromosome in a small population using two whole genome sequences (WGS) and 133 RAD sequences of white-tailed eagles (Haliaeetus albicilla): i) difference in read depth per scaffold in a male and a female, ii) heterozygosity per scaffold in a male and a female, iii) mapping to the reference genome of a related species (chicken) with annotated sex chromosomes, and iv) analysis of SNP-loadings from a principal components analysis (PCA), based on the low-depth RADseq data. Results: The best performing approach was the reference mapping (method iii), which identified 98.12% of the expected homogametic sex chromosome (Z). Read depth per scaffold (method i) identified 86.41% of the homogametic sex chromosome with few false positives. SNP-loading scores (method iv) identified 78.6% of the Z-chromosome and had a false positive discovery rate of more than 10%. Heterozygosity per scaffold (method ii) did not provide clear results due to a lack of diversity in both the Z and autosomal chromosomes, and potential interference from the heterogametic sex chromosome (W). The evaluation of these methods also revealed 10 Mb of putative PAR and gametologous regions. Conclusion: Identification of the homogametic sex chromosome in a small population is best accomplished by reference mapping or examining differences in read depth between sexes. [ABSTRACT FROM AUTHOR]

Introduction: The classic findings of acute appendicitis-right lower quadrant pain, anorexia, and leukocytosis-have been well known. However, emergency medicine and surgical providers continue to rely on imaging to confirm the diagnosis. We aimed to evaluate the increase in reliance on computed tomography (CT) scans for acute appendicitis diagnosis over time.Methods: We conducted a retrospective study of patients ≥18 years presenting to UNC Hospitals with signs and symptoms of acute appendicitis who subsequently underwent appendectomy from 2011 to 2015. Demographic, clinical, laboratory, and pathologic data were reviewed. We evaluated the incidence of CT scans stratified by year, age, and sex.Results: Within our male population, 55.2% (278/504) had classic appendicitis symptoms. Of the 278 male patients with classic appendicitis symptoms, 248 underwent CT imaging. Male patients <45 years of age were more likely to present with classic appendicitis symptoms (216/357, 60.5%) compared with patients aged 46-65 (52/108, 48.1%) or >65 (10/39, 25.6%). Of the male patients <45 years with classic appendicitis symptoms, the incidence of CT scans increased over time (68.3% in 2011, 84.2% in 2012, 92.3% in 2013, 93.9% in 2014, 92.3% in 2015). When considering the 216 CT scans that could have been avoided in our population, we calculate an approximate savings of $173 998.80 over 5 years.Conclusion: The incidence of CT scans for acute appendicitis confirmation has increased over time even in men. CT scans for the diagnosis or confirmation of acute appendicitis should rarely be indicated in men aged <45 years with classic appendicitis symptoms. [ABSTRACT FROM AUTHOR]

Prompt appendectomy has long been the standard of care for acute appendicitis because of the risk of progression to perforation. Recently, studies have suggested nonemergent management of acute appendicitis. Our study aimed to determine changes in risk of rupture and complications in patients with appendicitis, with increasing time from symptom onset to treatment. Retrospective study of patients aged ≥18 years presenting to the University of North Carolina Hospitals with signs and symptoms of acute appendicitis who subsequently underwent appendectomy from 2011 to 2015 was performed. Demographic, clinical, laboratory, and pathologic data were reviewed. Bivariate analysis was performed to assess variables associated with increased risk of perforation. Poisson regression modeling was completed to evaluate the risk of perforation and postoperative abscess based on time from symptoms to treatment. Within our database of 1007 patients, the mean time from onset of symptoms to operative intervention was 3.24 ± 2.2 days. Modified Poisson regression modeling demonstrated the relative risk for perforation increases by 9% (RR 1.09, P < 0.001) for each day delay. Age (RR 1.03), male gender (RR 1.50), temperature on admission (RR 1.32), and the presence of fecalith (RR 1.89) statistically significantly increased the risk of perforation. Furthermore, for each day delay, there is an 8% increased risk of postoperative abscess (RR 1.08, P = 0.027). The relative risk for appendiceal perforation is 9 per cent per day delay with a resultant 8 per cent increased risk of postoperative abscess. Thus, appendectomy for acute appendicitis should remain an emergent procedure, given that delays in operative management lead to complications and increases in cost of care. [ABSTRACT FROM AUTHOR]

Macrobrachium rosenbergii, the giant freshwater prawn, is an important source of high quality protein and occurs naturally in rivers as well as commercial farms in South and South-East Asia, including Bangladesh. This study investigated the genetic variation and population structure of M. rosenbergii sampled from four rivers in Bangladesh (sample size ranged from 19 to 20), assessing sequence variation, both in the mitochondrial cytochrome oxidase subunit 1 ( CO1) gene and in 106 single nucleotide polymorphisms ( SNPs) sampled randomly from the genome with double digest RAD sequencing (dd RADseq). The mitochondrial variation presented a shallow genealogy with high haplotype diversity ( h = 0.95), reflecting an expansion in population size for the last ~82 kyr. Based on the CO1 variation the current effective population size ( Ne) was 9.7 × 106 ( CI: 1.33 × 106 - 35.84 × 106) individuals. A significant population differentiation was observed with the mitochondrial CO1 sequence variation and based on the dd RADseq variation, which could be traced to the divergence of the population in the Naf River in the South-East border with Myanmar from the other populations. A differentiation in mt DNA haplotype frequencies was also observed between the Biskhali River and the Karnaphuli Rivers in eastern Bangladesh. This study demonstrated the use of high-throughput genotyping based on the dd RADseq method to reveal population structure at a small geographical scale for an important freshwater prawn. The information from this study can be utilized for management and conservation of this species in Bangladesh. [ABSTRACT FROM AUTHOR]

One potential harm of nonoperative management for acute appendicitis is missed appendiceal cancer, a rare and often aggressive malignancy due to the frequency of late stage of diagnosis. Previous studies have reported an increasing incidence of appendiceal neoplasms in the population. This is a retrospective case-control study of 1007 adult patients, who presented to the University of North Carolina-Memorial Hospital (UNC-MH) between 2011 and 2015 with clinical signs and symptoms of appendicitis. We evaluated the incidence of primary appendiceal cancer in this population and determined factors that predict appendiceal cancer diagnosis using multivariate logistic regression analysis. The overall incidence of appendiceal neoplasm for adult patients presenting to UNC-MH with appendicitis from 2011 to 2015 was 2.3 per cent (23/1007). The incidence in patients without appendiceal perforation on pathology was 1.9 per cent (16/832). Age (odds ratio (OR) 1.03), number of days of abdominal pain (OR 1.16), self-reported fever (OR 2.08), appendiceal width (OR 1.95), and appendiceal wall thickness (OR 1.30) were predictors of appendiceal neoplasm diagnosis in patients that present with acute appendicitis. We recommend that an operative approach to acute appendicitis should remain the standard of care because operative management may not only be diagnostic but potentially therapeutic. [ABSTRACT FROM AUTHOR]

Fenneropenaeus indicus (H. Milne-Edwards, 1837) is a commercially important penaeid shrimp in the Indo-Pacific region. Phylogenetics of penaeid shrimps is still a debatable issue and molecular variation within the species is large. The present study focuses on phylogeography of F. indicus and the phylogenetic relationships with four other species of Fenneropenaeus by assessing mitochondrial COl sequence variation of wild F. indicus sampled from Bangladesh in comparison with other populations. Fenneropenaeus indicus in Bangladesh waters consists of a single population (AMOVA: FST and ΦST, P > 0.05), which started to expand around 39-72 kyr ago. Although a high number of haplotypes is observed, the genealogical relationships are shallow and the overall variation is much less than off Sri Lanka. The different populations from the Indian Ocean show a clear geographical pattern with three distinct evolutionary lineages or cryptic species, one in the western Indian Ocean and Thailand and two in the eastern Indian Ocean, off Bangladesh and Sri Lanka. A phylogenetic analysis of Fenneropenaeus based on COI and 16S rRNA genes revealed that different lineages within F. indicus predate the speciation of other species within the genus, except for Fenneropenaeus chinensis (Osbeck, 1765). Fenneropenaeus indicus exhibited complex patterns of mtDNA and polyphyletic relationships within Fenneropenaeus, and the taxonomy needs to be re-evaluated. Our study will be helpful for management and conservation of shrimp diversity. [ABSTRACT FROM AUTHOR]

We report here on the abundance and distribution of a metapopulation of smooth-shelled blue mussels (genus Mytilus) from northeastern New Zealand (NZ), in the latitudinal range 37–35°S. Site surveys revealed the presence of blue mussels at 12 of 20 locations on the east coast of the Northland Peninsula, in the Hauraki Gulf and into the Bay of Islands region. Additional material was collected subsequently from three sites, including an estuary location in Auckland, which is the southern-most record of blue mussels in this northern region. This new record of an extensive, but patchily distributed metapopulation in northeastern NZ identifies the existence of a pronounced geographic discontinuity between 37°S and 41°S in the distribution of Mytilus throughout NZ. Based on its geographic isolation, we suggest that the northeastern metapopulation is genetically isolated from other more southerly distributed blue mussels in NZ. Molecular identification of the mussels was carried out by both nuclear and mitochondrial DNA RFLP assays. While the majority of mussels were identified as native Southern hemisphere M. galloprovincialis, a substantial number of individuals with a nonnative (Northern hemisphere) M. galloprovincialis mitotype were also identified. The identification of this new metapopulation composed of both northern and southern lineage M. galloprovincialis has challenging biosecurity and conservation implications. Because of the pronounced geographic break in the distribution of blue mussels in NZ it may be possible to minimize further spread of the northern lineage mitotype to the rest of the country using an internal borders containment approach. However, based on introductions of (Northern hemisphere) M. galloprovincialis elsewhere in the world, we believe that the most likely outcome in NZ of this bioincursion is extensive interbreeding and introgression between the northern and southern lineages of M. galloprovincialis. [ABSTRACT FROM PUBLISHER]

The taxonomic and evolutionary affinities of Southern hemisphere smooth-shelled blue mussels are unclear, with studies using different marker types having identified different relationships among various geographic regions. Using an existing and a new molecular assay, the present study builds on previous work to test the distribution of blue mussels native to and introduced to the Southern hemisphere. Populations of Mytilus were sampled from New Zealand, Australia, and Chile. The nuclear-DNA marker Me 15/16 was used to identify the taxonomic status of 484 individuals. A new restriction fragment length polymorphism (RFLP) assay was used to identify the hemisphere of origin for a subset of Mytilus galloprovincialis. The Me15/16 marker identified 478 pure M. galloprovincialis from Southern hemisphere sites and six Mytilus edulis/M. galloprovincialis hybrids from the Auckland Islands (New Zealand) and Chile. A cytoplasmic RFLP identified Northern hemisphere M. galloprovincialis in almost every Southern hemisphere region. The presence of native M. galloprovincialis at high latitudes (up to 52°S) has implications for our understanding of environmentally induced selective constraints considered to determine species distributions. Widespread occurrence of invasive Northern hemisphere blue mussels in the Southern hemisphere is documented for the first time. Identification of inter-specific hybrids ( M. edulis × M. galloprovincialis) in Chile and in the Auckland Islands (subantarctic New Zealand) illustrates that environments ranging from international ports to remote protected locations are vulnerable to bioinvasion. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, , 898-909. [ABSTRACT FROM AUTHOR]

Abstract: Geographical patterns in morphology can be the result of divergence among populations due to neutral or selective changes and/or phenotypic plasticity in response to different environments. Marine gastropods are ideal subjects on which to explore these patterns, by virtue of the remarkable intraspecific variation in life‐history traits and morphology often observed across relatively small spatial scales. The ubiquitous N‐Atlantic common whelk (Buccinum undatum) is well known for spatial variation in life‐history traits and morphology. Previous studies on genetic population structure have revealed that it exhibits significant differentiation across geographic distances. Within Breiðafjörður Bay, a large and shallow bay in W‐Iceland, genetic differentiation was demonstrated between whelks from sites separated by just 20 km. Here, we extended our previous studies on the common whelk in Breiðafjörður Bay by quantifying phenotypic variation in shell morphology and color throughout the Bay. We sought to test whether trait differentiation is dependent on geographic distance and/or environmental variability. Whelk in Breiðafjörður Bay displayed fine‐scale patterns of spatial variation in shape, thickness, and color diversity. Differentiation increased with increasing distance between populations, indicating that population connectivity is limited. Both shape and color varied along a gradient from the inner part of the bay in the east to the outer part in the west. Whelk shells in the innermost part of Breiðafjörður Bay were thick with an elongate shell, round aperture, and low color diversity, whereas in the outer part of the bay the shells were thinner, rounder, with a more elongate aperture and richer color diversity. Significant site‐specific difference in shell traits of the common whelk in correlation with environmental variables indicates the presence of local ecotypes and limited demographic connectivity. [ABSTRACT FROM AUTHOR]

A correction to the article "Historical DNA reveals the demographic history of Atlantic cod (Gadus morhua) in medieval and early modern Iceland" that was published in the 2014 issue is presented.

Atlantic cod (Gadus morhua) vertebrae from archaeological sites were used to study the history of the Icelandic Atlantic cod population in the time period of 1500-1990. Specifically, we used coalescence modelling to estimate population size and fluctuations from the sequence diversity at the cytochrome b (cytb) and Pantophysin I (PanI) loci. The models are consistent with an expanding population during the warm medieval period, large historical effective population size (NE), a marked bottleneck event at 1400-1500 and a decrease in NE in early modern times. The model results are corroborated by the reduction of haplotype and nucleotide variation over time and pairwise population distance as a significant portion of nucleotide variation partitioned across the 1550 time mark. The mean age of the historical fished stock is high in medieval times with a truncation in age in early modern times. The population size crash coincides with a period of known cooling in the North Atlantic, and we conclude that the collapse may be related to climate or climate-induced ecosystem change. [ABSTRACT FROM AUTHOR]

Human-mediated biological transfers of species have substantially modified many ecosystems with profound environmental and economic consequences. However, in many cases, invasion events are very hard to identify because of the absence of an appropriate baseline of information for receiving sites/regions. In this study, use of high-resolution genetic markers (single nucleotide polymorphisms - SNPs) highlights the threat of introduced Northern Hemisphere blue mussels ( Mytilus galloprovincialis) at a regional scale to Southern Hemisphere lineages of blue mussels via hybridization and introgression. Analysis of a multispecies SNP dataset reveals hotspots of invasive Northern Hemisphere blue mussels in some mainland New Zealand locations, as well as the existence of unique native lineages of blue mussels on remote oceanic islands in the Southern Ocean that are now threatened by invasive mussels. Samples collected from an oil rig that has moved between South Africa, Australia, and New Zealand were identified as invasive Northern Hemisphere mussels, revealing the relative ease with which such non-native species may be moved from region to region. In combination, our results highlight the existence of unique lineages of mussels (and by extension, presumably of other taxa) on remote offshore islands in the Southern Ocean, the need for more baseline data to help identify bioinvasion events, the ongoing threat of hybridization and introgression posed by invasive species, and the need for greater protection of some of the world's last great remote areas. [ABSTRACT FROM AUTHOR]

Marine Protected Areas (MPAs) have been adopted globally as a tool to combat biodiversity loss and restore marine ecosystems. Successful application of MPAs will be predicated on the ability to monitor biodiversity in a synoptic and noninvasive manner. Environmental DNA (eDNA) methods have important advantages over traditional biodiversity survey methods for monitoring conservation areas. To evaluate the efficacy of eDNA metabarcoding for fish biodiversity monitoring, we sampled 19 coastal eelgrass (Zostera marina) beds in Canada, as eelgrass beds are known for high biodiversity and significant conservation value. At each site, beach seines were used to survey fish and water samples were collected contemporaneously for eDNA metabarcoding. In total, beach seining caught 32 672 individuals across 59 fish taxa, and eDNA detected 129 fish taxa. eDNA captured site-level variation and detected higher species richness at both site and regional levels compared to seining. eDNA abundance had a positive association with capture abundance. Collectively these results highlight how eDNA metabarcoding offers an efficient approach for monitoring fish biodiversity in coastal eelgrass beds, thus providing a valuable and noninvasive tool for MPA planning and coastal monitoring. [ABSTRACT FROM AUTHOR]

Aims Obesity and hyperlipidaemia are associated with insulin resistance (IR); however, the mechanisms responsible remain incompletely understood. Pro-atherogenic hyperlipidaemic states are characterized by inflammation, oxidant stress, and pathophysiologic oxidized lipids, including ligands for the scavenger receptor CD36. Here we tested the hypothesis that the absence of CD36 protects mice from IR associated with diet-induced obesity and hyperlipidaemia. Methods and results Adipose tissue from CD36−/− mice demonstrated a less inflammatory phenotype and improved insulin signalling in vivo and at the level of the adipocyte and macrophage. The pathophysiologic ligand oxidized low-density lipoprotein (oxLDL) activated c-Jun N-terminal kinase (JNK) and disrupted insulin signalling in both adipocytes and macrophages in a CD36-dependent manner. Macrophages isolated from CD36−/− mice after high-fat diet feeding elicited less JNK activation and inhibition of insulin signalling in adipocytes after co-culture compared with wild-type macrophages. Conclusion These data suggest that a CD36-dependent inflammatory paracrine loop between adipocytes and macrophages facilitates chronic inflammation and contributes to IR common in obesity and dyslipidaemia. [ABSTRACT FROM AUTHOR]

Environmental DNA (eDNA) metabarcoding can rapidly characterize the composition and diversity of benthic communities, thus it has high potential utility for routine assessments of benthic impacts of marine finfish farming. In this study, 126 sediment grab samples from 42 stations were collected at six salmon farms in British Columbia, Canada. Benthic community changes were assessed by both eDNA metabarcoding of metazoans and macrofaunal polychaete surveys. The latter was done by analysing 11,466 individuals using a combination of morphology‐based taxonomy and DNA barcoding. Study objectives were to: (i) compare biotic signals associated with benthic impacts of salmon farming in the two data sources, and (ii) identify potential eDNA indicators to facilitate monitoring in Canada. Alpha diversity parameters were consistently reduced near fish cage edge and negatively correlated with pore‐water sulphide concentration, with coefficients ranging from −0.62 to −0.48. Although Polychaeta are a common indicator group, the negative correlation with pore‐water sulphide concentration was much stronger for Nematoda OTU richness (correlation coefficient: −0.86) than for Polychaeta (correlation coefficient: −0.38). Presence/absence of Capitella generally agreed well between the two methods despite that they differed in the volume of sediments sampled and the molecular marker used. Multiple approaches were used to identify OTUs related to organic enrichment statuses. We demonstrate that eDNA metabarcoding generates biotic signals that could be leveraged for environmental assessment of benthic impacts of fish farms in multiple ways: both alpha diversity and Nematoda OTU richness could be used to assess the spatial extent of impact, and OTUs related to organic enrichment could be used to develop local biotic indices. [ABSTRACT FROM AUTHOR]