Accessing the Low-Polar Molecular Composition of Boreal and Arctic Peat-Burning Organic Aerosol via Thermal Analysis and Ultrahigh-Resolution Mass Spectrometry: Structural Motifs and Their Formation.

Peatland fires emit organic carbon-rich particulate matter into the atmosphere. Boreal and Arctic peatlands are becoming more vulnerable to wildfires, resulting in a need for better understanding of the emissions of these special fires. Extractable, nonpolar, and low-polar organic aerosol species emitted from laboratory-based boreal and Arctic peat-burning experiments are analyzed by direct-infusion atmospheric pressure photoionization (APPI) ultrahigh-resolution mass spectrometry (UHRMS) and compared to time-resolved APPI UHRMS evolved gas analysis from the thermal analysis of peat under inert nitrogen (pyrolysis) and oxidative atmosphere. The chemical composition is characterized on a molecular level, revealing abundant aromatic compounds that partially contain oxygen, nitrogen, or sulfur and are formed at characteristic temperatures. Two main structural motifs are identified, single core and multicore, and their temperature-dependent formation is assigned to the thermal degradation of the lignocellulose building blocks and other parts of peat.

Accumulation of Per- and Polyfluoroalkyl Substances (PFAS) in Coastal Sharks from Contrasting Marine Environments: The New York Bight and The Bahamas.

Per- and polyfluoroalkyl substances (PFAS) enter the marine food web, accumulate in organisms, and potentially have adverse effects on predators and consumers of seafood. However, evaluations of PFAS in meso-to-apex predators, like sharks, are scarce. This study investigated PFAS occurrence in five shark species from two marine ecosystems with contrasting relative human population densities, the New York Bight (NYB) and the coastal waters of The Bahamas archipelago. The total detected PFAS (∑PFAS) concentrations in muscle tissue ranged from 1.10 to 58.5 ng g-1 wet weight, and perfluorocarboxylic acids (PFCAs) were dominant. Fewer PFAS were detected in Caribbean reef sharks (Carcharhinus perezi) from The Bahamas, and concentrations of those detected were, on average, ∼79% lower than in the NYB sharks. In the NYB, ∑PFAS concentrations followed: common thresher (Alopias vulpinus) > shortfin mako (Isurus oxyrinchus) > sandbar (Carcharhinus plumbeus) > smooth dogfish (Mustelus canis). PFAS precursors/intermediates, such as 2H,2H,3H,3H-perfluorodecanoic acid and perfluorooctanesulfonamide, were only detected in the NYB sharks, suggesting higher ambient concentrations and diversity of PFAS sources in this region. Ultralong-chain PFAS (C ≥ 10) were positively correlated with nitrogen isotope values (δ15N) and total mercury in some species. Our results provide some of the first baseline information on PFAS concentrations in shark species from the northwest Atlantic Ocean, and correlations between PFAS, stable isotopes, and mercury further contextualize the drivers of PFAS occurrence.

The Degree of Inferior Vena Cava Filter Tilt Associated with Challenging Retrieval.

OBJECTIVE: Inferior vena cava (IVC) filter tilt is associated with technical difficulties at the time of retrieval. However, the degree of tilt that predisposes patients to undergo complex or failed retrieval has not been defined. METHODS: The electronic charts of patients undergoing IVC filter removal between 2010 and 2019 at a single tertiary center were reviewed. Patient and procedural characteristics were recorded. Venograms of placement and retrieval procedures were reviewed, and IVC filter tilt was determined based on its deviation from the IVC axis. IVC diameter and the distance from the lowest renal vein were measured using corresponding filter's length for calibration. All measurements were performed by 3 reviewers and confirmed by 2 reviewers. Patients were divided into 2 groups: those who underwent successful removal procedures requiring standard retrieval methods ("simple retrieval group") and those who required advanced endovascular techniques or had failed completely IVC filter retrievals ("challenging retrieval group"). A regression analysis was performed to determine factors associated with challenging retrieval. RESULTS: There were 365 patients who underwent IVC filter retrieval (n=294 (80.6%) and n=71 (19.4%) in the simple and challenging groups, respectively) with no difference in age, sex, comorbidities or indication between the 2 groups. Failed retrieval occurred in 21 patients (5.8%) and was more common among patients requiring advanced endovascular techniques compared to standard techniques (18.0% vs. 3.2%, p < 0.001). In the overall cohort, the mean filter tilt at the time of retrieval was 4.9° ± 4.4° [0 - 27°], and 145 patients (39.7%) had a filter tilt ≥ 5.0°. Compared to the simple retrieval group, patients in the challenging group had significantly longer dwell time, greater tilt of IVC filter during placement and retrieval, as well as higher tilt change between the 2 venograms. There was no correlation between the access site during placement and challenging retrieval. However, patients undergoing filter placement via right jugular vein had lower filter tilt as compared to femoral access. Patients with filter tilt ≥ 5.0° were more likely to have a challenging filter retrieval compared to patients with ˂ 5.0° tilt (29.7% vs 12.7%, p<0.001). Regression analysis showed that tilt ≥ 5.0° (OR=1.18 [1.11-1.25]), dwell time (OR=1.04 [1.01-1.07]), and age (OR=0.97 [0.95-0.99]) were independently associated with challenging retrieval. CONCLUSION: IVC filter tilt ≥ 5.0°, dwell time and age are associated with challenging retrieval. Right jugular vein access, multiple imaging projections, and careful filter manipulation during deployment should be considered to maintain tilt at ˂ 5.0° and decrease the likelihood of challenging retrieval.

PLX038A, a long-acting SN-38, penetrates the blood-tumor-brain-barrier, accumulates and releases SN-38 in brain tumors to increase survival of tumor bearing mice.

Central nervous system tumors have resisted effective chemotherapy because most therapeutics do not penetrate the blood-tumor-brain-barrier. Nanomedicines between ~ 10 and 100 nm accumulate in many solid tumors by the enhanced permeability and retention effect, but it is controversial whether the effect can be exploited for treatment of brain tumors. PLX038A is a long-acting prodrug of the topoisomerase 1 inhibitor SN-38. It is composed of a 15 nm 4-arm 40 kDa PEG tethered to four SN-38 moieties by linkers that slowly cleave to release the SN-38. The prodrug was remarkably effective at suppressing growth of intracranial breast cancer and glioblastoma (GBM), significantly increasing the life span of mice harboring them. We addressed the important issue of whether the prodrug releases SN-38 systemically and then penetrates the brain to exert anti-tumor effects, or whether it directly penetrates the blood-tumor-brain-barrier and releases the SN-38 cargo within the tumor. We argue that the amount of SN-38 formed systemically is insufficient to inhibit the tumors, and show by PET imaging that a close surrogate of the 40 kDa PEG carrier in PLX038A accumulates and is retained in the GBM. We conclude that the prodrug penetrates the blood-tumor-brain-barrier, accumulates in the tumor microenvironment and releases its SN-38 cargo from within. Based on our results, we pose the provocative question as to whether the 40 kDa nanomolecule PEG carrier might serve as a "Trojan horse" to carry other drugs past the blood-tumor-brain-barrier and release them into brain tumors.

Heterogeneous gene expression during early arteriovenous fistula remodeling suggests that downregulation of metabolism predicts adaptive venous remodeling.

Clinical outcomes of arteriovenous fistulae (AVF) for hemodialysis remain inadequate since biological mechanisms of AVF maturation and failure are still poorly understood. Aortocaval fistula creation (AVF group) or a sham operation (sham group) was performed in C57BL/6 mice. Venous limbs were collected on postoperative day 7 and total RNA was extracted for high throughput RNA sequencing and bioinformatic analysis. Genes in metabolic pathways were significantly downregulated in the AVF, whereas significant sex differences were not detected. Since gene expression patterns among the AVF group were heterogenous, the AVF group was divided into a 'normal' AVF (nAVF) group and an 'outliers' (OUT) group. The gene expression patterns of the nAVF and OUT groups were consistent with previously published data showing venous adaptive remodeling, whereas enrichment analyses showed significant upregulation of metabolism, inflammation and coagulation in the OUT group compared to the nAVF group, suggesting the heterogeneity during venous remodeling reflects early gene expression changes that may correlate with AVF maturation or failure. Early detection of these processes may be a translational strategy to predict fistula failure and reduce patient morbidity.

Molecular composition of fresh and aged aerosols from residential wood combustion and gasoline car with modern emission mitigation technology.

Emissions from road traffic and residential heating contribute to urban air pollution. Advances in emission reduction technologies may alter the composition of emissions and affect their fate during atmospheric processing. Here, emissions of a gasoline car and a wood stove, both equipped with modern emission mitigation technology, were photochemically aged in an oxidation flow reactor to the equivalent of one to five days of photochemical aging. Fresh and aged exhausts were analyzed by ultrahigh resolution mass spectrometry. The gasoline car equipped with a three-way catalyst and a gasoline particle filter emitted minor primary fine particulate matter (PM2.5), but aging led to formation of particulate low-volatile, oxygenated and highly nitrogen-containing compounds, formed from volatile organic compounds (VOCs) and gases incl. NOx, SO2, and NH3. Reduction of the particle concentration was also observed for the application of an electrostatic precipitator with residential wood combustion but with no significant effect on the chemical composition of PM2.5. Comparing the effect of short and medium photochemical exposures on PM2.5 of both emission sources indicates a similar trend for formation of new organic compounds with increased carbon oxidation state and nitrogen content. The overall bulk compositions of the studied emission exhausts became more similar by aging, with many newly formed elemental compositions being shared. However, the presence of particulate matter in wood combustion results in differences in the molecular properties of secondary particles, as some compounds were preserved during aging.

Synergistic Antitumor Activity of Talazoparib and Temozolomide in Malignant Rhabdoid Tumors.

Malignant rhabdoid tumors (MRTs) are among the most aggressive and treatment-resistant malignancies affecting infants, originating in the kidney, brain, liver, and soft tissues. The 5-year event-free survival rate for these cancers is a mere 20%. In nearly all cases of MRT, the SMARCB1 gene (occasionally SMARCA4)-a pivotal component of the SWI/SNF chromatin remodeling complex-is homozygously deleted, although the precise etiology of these tumors remains unknown. While young patients with localized MRT generally show improved outcomes, especially those who are older and have early-stage disease, the overall prognosis remains poor despite optimal standard treatments. This highlights the urgent need for more effective treatment strategies. We investigated the antitumor activity of a PARP1 inhibitor (talazoparib, TLZ) combined with a DNA alkylating agent (temozolomide, TMZ) in MRT xenograft models. PARP1 is a widely targeted molecule in cancer treatment and, beyond its role in DNA repair, it participates in transcriptional regulation by recruiting chromatin remodeling complexes to modulate DNA accessibility for RNA polymerases. To widen the therapeutic window of the drug combination, we employed PEGylated TLZ (PEG~TLZ), which has been reported to reduce systemic toxicity through slow drug release. Remarkably, our findings indicate that five out of six MRT xenografts exhibited an objective response to PEG~TLZ+TMZ therapy. Significantly, the loss of SMARCB1 was found to confer a protective effect, correlating with higher expression levels of DNA damage and repair proteins in SMARCB1-deficient MRT cells. Additionally, we identified MGMT as a potential biomarker indicative of in vivo MRT response to PEG~TLZ+TMZ therapy. Moreover, our analysis revealed alterations in signaling pathways associated with the observed antitumor efficacy. This study presents a novel and efficacious therapeutic approach for MRT, along with a promising candidate biomarker for predicting tumor response.

Common Data Elements and Databases Essential for the Study of Musculoskeletal Injuries in Military Personnel.

INTRODUCTION: Injuries are the leading cause of medical encounters with over 2 million medical encounters for musculoskeletal (MSK) conditions and over 700,000 acute injuries per year. Musculoskeletal injuries (MSKIs) are by far the leading health and readiness problem of the U.S. Military. The Proceedings of the International Collaborative Effort on Injury Statistics published a list of 12 data elements deemed necessary for injury prevention in the civilian population; however, there are no standardized list of common data elements (CDEs) across the DoD specifically designed to study MSKIs in the Military Health System (MHS). This study aims to address this gap in knowledge by defining CDEs across the DoD for MSKIs, establishing a CDE dictionary, and compiling other necessary information to quantify MSKI disease burden in the MHS. MATERIALS AND METHODS: Between November 2022 and March 2023, we conducted an environmental scan of current MSKI data metrics across the DoD. We used snowball sampling with active engagement of groups housing datasets that contained MSKI data elements to determine CDEs as well as information on readiness databases across the DoD containing up-to-date personnel information on disease, hospitalizations, limited duty days (LDDs), and deployability status for all military personnel, as well as MSKI-specific measures from the MHS Dashboard which tracks key performance measures. RESULTS: We identified 8 unique databases: 5 containing demographic and diagnostic information (Defense Medical Surveillance System, Medical Assessment and Readiness Systems, Military Health System Data Repository, Person-Data Environment, and Soldier Performance, Health, and Readiness Database); and 3 containing LDD information (Aeromedical Services Information Management System, eProfile, and Limited Duty Sailor Marines Readiness Tracker). Nine CDEs were identified: DoD number, sex, race, ethnicity, branch of service, rank, diagnosis, Common Procedural Terminology coding, and cause codes, as they may be captured in any database that is a derivative of the Military Health System Data Repository. Medical Assessment and Readiness Systems contained most variables of interest, excluding injury/place of region and time in service. The Limited Duty Sailor Marines Readiness Tracker contains a variable corresponding to "days on limited duty." The Aeromedical Services Information Management System uses the "release date" and "profile date" to calculate LDDs. The eProfile system determines LDDs by the difference between the "expiration date" and "approved date." In addition, we identified 2 measures on the MHS Dashboard. One measures the percentage of service members (SMs) who are on limited duty for longer than 90 days because of an MSKI and the other tracks the percentage of SMs that are not medically ready for deployment because of a deployment-limiting medical condition. CONCLUSIONS: This article identifies core data elements needed to understand and prevent MSKIs and where these data elements can be found. These elements should inform researchers and result in evidence-informed policy decisions supporting SM health to optimize military force readiness.

Home Optical Coherence Tomography Monitoring for Neovascular Age-Related Macular Degeneration: Transformative Technology or Cool Toy?

The pending introduction of home-based optical coherence tomography (OCT) in managing neovascular age-related macular degeneration (nAMD) has sparked interesting debates. Advocates assert that home-based OCT will revolutionize care of patients with nAMD, while skeptics question its real-world viability and point out its potential drawbacks. This article delves into the dichotomy, presenting the "pro" argument highlighting the transformative potential of home OCT and the "con" perspective, which scrutinizes the limitations and challenges to adapting the technology to the real-world setting. By exploring both sides of the discourse, we aim to address the promises and complexities surrounding the role of home OCT in the management of nAMD.

Expanding records of occurrence of the whale shark (Rhincodon typus) in The Bahamas and a call for sustainable tourism practices.

This report updates our understanding of whale shark occurrences in The Bahamas by drawing upon a variety of data sources. Our findings reveal previously unreported sighting locations, often associated with tourism activities, underscoring the pivotal role played by nontraditional data sources in addressing knowledge gaps. These revelations emphasize the ongoing necessity for monitoring efforts. Additionally, we have found cases that raise concerns related to unregulated human-shark interactions in the region, highlighting the pressing need for sustainable tourism practices within Bahamian waters.

A Cross-Sectional Analysis of Pediatric Necrotizing Soft Tissue Infection Cases and Racial Disparities From the 2016 to 2020 National Inpatient Sample.

INTRODUCTION: The incidence, treatment, and outcomes of necrotizing soft tissue infections (NSTIs) and associated racial disparities have been described in adults, but research in the pediatric population is limited. The purpose of this study is to provide a nationally representative characterization of pediatric NSTI and determine the presence of any racial disparities. METHODS: The National Inpatient Sample was analyzed from 2016 through 2020. Patients aged less than 20 y with a diagnosis of necrotizing fasciitis, Fournier's gangrene, or gas gangrene (based on International Classification of Diseases, Tenth Revision, Clinical Modification codes) were included for analysis. RESULTS: A total of 355 patients were identified. Black and Hispanic patients accounted for the most admissions in 2016 and 2018, respectively (P = 0.024). Compared to White patients, more Black patients were insured by Medicaid (P = 0.037) and were in the first zip code-based income quartile (P = 0.005). The leading infection overall was necrotizing fasciitis and most patients (81.7%) underwent a surgical procedure by the first calendar day after admission. Although the proportion of Black patients undergoing subcutaneous tissue and fascia excisions was more than that of White patients (P = 0.005), there were no significant differences by race in the time to first procedure, the total number of procedures, or number of postoperative complications. Our amputation and mortality rates were low and unreportable, but there were no differences by race. CONCLUSIONS: NSTI is rare in the pediatric population and mortality is low. Black patients are disproportionately diagnosed, but these disparities do not extend to disease treatment or outcomes.

The impact of undergoing elective pediatric lung resection during respiratory syncytial virus peak season on patient outcomes: A nationwide retrospective analysis.

OBJECTIVES: Observational data to support delaying elective pediatric thoracic surgery during peak respiratory viral illness season is lacking. This study evaluated whether lung surgery during peak viral season is associated with differences in postoperative outcomes and resource utilization. METHODS: A retrospective observational cohort study was performed using the Pediatric Health Information System (PHIS). Patients with a congenital lung malformation (CLM) who underwent elective lung resection between 1 January 2016 and 29 February 2020 were included. Respiratory syncytial virus (RSV) incidence was used as a proxy for respiratory viral illness circulation. Monthly hospital-specific RSV incidence was calculated from PHIS data, and peak RSV season was defined by Centers for Disease Control data. Multivariable regression models were built to identify predictors of postoperative mechanical ventilation, which was the main outcome measure, as well as secondary outcomes including 30-day readmission after lung resection, postoperative length of stay (LOS) and hospital billing charges. RESULTS: Of 1542 CLM patients identified, 344 (22.3%) underwent lung resection during peak RSV season. 38% fewer operations were performed per month during peak RSV season than during off-peak months (p < .001). Children who underwent surgery during peak RSV season did not differ from the off-peak group in terms of age at operation, race, or comorbid conditions (i.e., congenital heart disease, newborn respiratory distress, and preoperative pneumonia). There was no association between hospital-specific RSV incidence at the time of surgery and postoperative mechanical ventilation, postoperative LOS, 30-day readmission rate or hospital billing charges. DISCUSSION: Performing elective lung surgery in children with CLMs during peak viral season is not associated with adverse surgical outcomes or increased utilization of healthcare resources.

A new species of deep-sea Booralana Bruce, 1986 (Crustacea: Isopoda: Cirolanidae) from The Bahamas, Western North Atlantic.

Booralana nickorum sp. nov. is described from the deep-water slope of the Exuma Sound, The Bahamas, from depths of 540 to 560 metres. It is the fourth species to be assigned to the genus and the second species described from the Western North Atlantic. The species can be distinguished from Booralana tricarinata Camp and Heard, 1988 and the other species by the sub-triangular pleotelson and the uropodal exopod of mature males being far longer than endopod, with both rami extending well beyond the posterior margin of the pleotelson. Additionally, pleopods 3 and 4 lack a prominent angle at midpoint of ramus.

On the dual behaviour of water in octanol-rich aqueous n-octanol mixtures: an X-ray scattering and computer simulation study.

Aqueous n-octanol (n = 1, 2, 3, and 4) mixtures from the octanol rich side are studied by X-ray scattering and computer simulation, with a focus on structural changes, particularly in what concerns the hydration of the hydroxyl-group aggregated chain-like structures, under the influence of various branching of the alkyl tails. Previous studies have indicated that hydroxyl-group chain-cluster formation is hindered in proportion to the branching number. Here, water mole fractions up to x = 0.2 are examined, i.e. up to the miscibility limit. It is found that water molecules within the hydroxyl-chain domains participate in the chain formations in a different manner for 1-octanol and the branched octanols. The hydration of the octanol hydroxyl chains is confirmed by the shifting of the scattering pre-peak position kPP to smaller values, both from measured and simulated X-ray scattering intensities, which corresponds to an increased size of the clusters. Experimental pre-peak amplitudes are seen to increase with increasing water content for 1-octanol, while this trend is reversed in all branched octanols, with the amplitudes decreasing with the increase of the branching number. Conjecturing that the amplitudes of pre-peaks are related to the density of the corresponding aggregates, these results are interpreted as water breaking large OH hydroxyl chains in 1-octanol, hence increasing the density of aggregates, while enhancing hydroxyl aggregates in branched alcohols by inserting itself into the OH chains. The analysis of the cluster distributions from computer simulations provide more details on the role of water. For cluster sizes smaller than dc = 2π/kPP, water is found to always play the role of a structure enforcer for all n-octanols, while for clusters of size dc water is always a destructor. For cluster sizes larger than dc, the role of water differs from 1-octanol and the branched ones: it acts as a structure maker or breaker in inverse proportion to the hindering of OH hydroxyl chain structures arising from the topology of the alkyl tails (branched or not).

Wildfire plume ageing in the Photochemical Large Aerosol Chamber (PHOTO-LAC).

Plumes from wildfires are transported over large distances from remote to populated areas and threaten sensitive ecosystems. Dense wildfire plumes are processed by atmospheric oxidants and complex multiphase chemistry, differing from processes at typical ambient concentrations. For studying dense biomass burning plume chemistry in the laboratory, we establish a Photochemical Large Aerosol Chamber (PHOTO-LAC) being the world's largest aerosol chamber with a volume of 1800 m3 and provide its figures of merit. While the photolysis rate of NO2 (jNO2) is comparable to that of other chambers, the PHOTO-LAC and its associated low surface-to-volume ratio lead to exceptionally low losses of particles to the walls. Photochemical ageing of toluene under high-NOx conditions induces substantial formation of secondary organic aerosols (SOAs) and brown carbon (BrC). Several individual nitrophenolic compounds could be detected by high resolution mass spectrometry, demonstrating similar photochemistry to other environmental chambers. Biomass burning aerosols are generated from pine wood and debris under flaming and smouldering combustion conditions and subsequently aged under photochemical and dark ageing conditions, thus resembling day- and night-time atmospheric chemistry. In the unprecedented long ageing with alternating photochemical and dark ageing conditions, the temporal evolution of particulate matter and its chemical composition is shown by ultra-high resolution mass spectrometry. Due to the spacious cavity, the PHOTO-LAC may be used for applications requiring large amounts of particulate matter, such as comprehensive chemical aerosol characterisation or cell exposures under submersed conditions.

The Degree of Preoperative Hypoalbuminemia Is Associated with Risk of Postoperative Complications in Metabolic and Bariatric Surgery Patients.

BACKGROUND: The incidence and impact of hypoalbuminemia in bariatric surgery patients is poorly characterized. We describe its distribution in laparoscopic sleeve gastrectomy (VSG) and Roux-en-Y gastric bypass (RYGB) patients undergoing primary or revision surgeries and assess its impact on postoperative complications. METHODS: The Metabolic and Bariatric Surgery Quality Improvement Program Database (2015 to 2021) was analyzed. Hypoalbuminemia was defined as Severe (< 3 g/dL), Moderate (3 ≤ 3.5 g/dL), Mild (3.5 ≤ 4 g/dL), or Normal (≥ 4 g/dL). Multivariable logistic regression was performed to calculate odds ratios of postoperative complications compared to those with Normal albumin after controlling for procedure, age, gender, race, body mass index, functional status, American Society of Anesthesia class, and operative length. RESULTS: A total of 817,310 patients undergoing Primary surgery and 69,938 patients undergoing Revision/Conversion ("Revision") surgery were analyzed. The prevalence of hypoalbuminemia was as follows (Primary, Revision): Severe, 0.3%, 0.6%; Moderate, 5.2%, 6.5%; Mild, 28.3%, 31.4%; Normal, 66.2%, 61.4%. Primary and Revision patients with hypoalbuminemia had a significantly higher prevalence (p < 0.01) of several co-morbidities, including hypertension and insulin-dependent diabetes. Any degree of hypoalbuminemia increased the odds ratio of several complications in Primary and Revision patients, including readmission, intervention, and reoperation. In Primary patients, all levels of hypoalbuminemia also increased the odds ratio of unplanned intubation, intensive care unit admission, and venous thromboembolism requiring therapy. CONCLUSION: Over 30% of patients present with hypoalbuminemia. Even mild hypoalbuminemia was associated with an increased rate of several complications including readmission, intervention, and reoperation. Ensuring nutritional optimization, especially prior to revision surgery, may improve outcomes in this challenging population.

Colonization, diversity, and seasonality of fishes at pelagic fish aggregating devices.

The pelagic zone of the ocean can be a challenging environment in which to conduct research and as a result we lack the robust baseline abundance and diversity data, compared to what is available in more accessible coastal habitats, to be able to track changes or stressors to the biota in this environment. Many large-scale fisheries target pelagic fish, and much of the information available on these species is based on fisheries-dependent data that may be biased towards hotspots and commercially valuable fishes. Here, a long-term video and visual fish survey was conducted on two subsurface moored fish aggregating devices (FADs) in the pelagic waters of the central Bahamas to determine the feasibility of using moored pelagic FADs as tools for collecting fish abundance and diversity data. A wide range of species was documented, including large migratory fish that are the focus of commercial and recreational fisheries, and smaller often overlooked species on which little abundance or seasonality information exists. We found that FADs colonize quickly and reach a peak stable (albeit seasonally cyclical) abundance and diversity within the first several months after deployment. Species richness was higher in video surveys, but abundance was higher in visual surveys, except for sharks. Our results highlight the need to tailor survey methods to fit the context and study objective, and provide further evidence for the importance of fisheries-independent data in monitoring pelagic species.

Habitat-specific impacts of climate change on the trophic demand of a marine predator.

Metabolic ecology predicts that ectotherm metabolic rates, and thus consumption rates, will increase with body size and temperature. Predicted climatic increases in temperature are likely to increase the consumption rates of ectothermic predators; however, the ecological impact of these increases will partly depend on whether prey productivity changes with temperature at a similar rate. Furthermore, total predator consumption and prey productivity will depend on species abundances that vary across habitat types. Here we combine energetics and biotelemetry to measure consumption rates in a critically endangered coral reef predator, the Nassau grouper (Epinephelus striatus), in The Bahamas. We estimate that, at present, the Nassau grouper needs to consume 2.2% ± 1.0% body weight day-1 , but this could increase up to 24% with a predicted 3.1°C increase in ocean temperature by the end of the century. We then used surveys of prey communities in two major reef habitat types (Orbicella reef and Gorgonian plain), to predict the proportion of prey productivity consumed by grouper and how this varied by habitat with changing climates. We found that at present, the predicted proportion of prey productivity consumed by Nassau grouper decreased with increasing prey productivity and averaged 1.2% across all habitats, with a greater proportion of prey productivity consumed (maximum of 5%) in Gorgonian plain habitats. However, because temperature increases consumption rates faster than prey productivity, the proportion of prey productivity consumed in a Gorgonian plain habitat could increase up to 24% under future climate change scenarios. Our results suggest that increasing ocean temperatures will lead to significant energetic challenges for the Nassau grouper because of differential impacts within reef food webs, but the magnitude of these impacts will probably vary across prey productivity gradients.

Emergent Applications of Machine Learning for Diagnosing and Managing Appendicitis: A State-of-the-Art Review.

Background: Appendicitis is an inflammatory condition that requires timely and effective intervention. Despite being one of the most common surgically treated diseases, the condition is difficult to diagnose because of atypical presentations. Ultrasound and computed tomography (CT) imaging improve the sensitivity and specificity of diagnoses, yet these tools bear the drawbacks of high operator dependency and radiation exposure, respectively. However, new artificial intelligence tools (such as machine learning) may be able to address these shortcomings. Methods: We conducted a state-of-the-art review to delineate the various use cases of emerging machine learning algorithms for diagnosing and managing appendicitis in recent literature. The query ("Appendectomy" OR "Appendicitis") AND ("Machine Learning" OR "Artificial Intelligence") was searched across three databases for publications ranging from 2012 to 2022. Upon filtering for duplicates and based on our predefined inclusion criteria, 39 relevant studies were identified. Results: The algorithms used in these studies performed with an average accuracy of 86% (18/39), a sensitivity of 81% (16/39), a specificity of 75% (16/39), and area under the receiver operating characteristic curves (AUROCs) of 0.82 (15/39) where reported. Based on accuracy alone, the optimal model was logistic regression in 18% of studies, an artificial neural network in 15%, a random forest in 13%, and a support vector machine in 10%. Conclusions: The identified studies suggest that machine learning may provide a novel solution for diagnosing appendicitis and preparing for patient-specific post-operative complications. However, further studies are warranted to assess the feasibility and advisability of implementing machine learning-based tools in clinical practice.