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Harmful algal blooms (HABs) are increasing globally, causing economic, human health, and ecosystem harm. In spite of the frequent occurrence of HABs, the mechanisms responsible for their exceptionally high biomass remain imperfectly understood. A 50-y-old hypothesis posits that some dense blooms derive from dinoflagellate motility: organisms swim upward during the day to photosynthesize and downward at night to access deep nutrients. This allows dinoflagellates to outgrow their nonmotile competitors. We tested this hypothesis with in situ data from an autonomous, ocean-wave-powered vertical profiling system. We showed that the dinoflagellate Lingulodinium polyedras vertical migration led to depletion of deep nitrate during a 2020 red tide HAB event. Downward migration began at dusk, with the maximum migration depth determined by local nitrate concentrations. Losses of nitrate at depth were balanced by proportional increases in phytoplankton chlorophyll concentrations and suspended particle load, conclusively linking vertical migration to the access and assimilation of deep nitrate in the ocean environment. Vertical migration during the red tide created anomalous biogeochemical conditions compared to 70 y of climatological data, demonstrating the capacity of these events to temporarily reshape the coastal oceans ecosystem and biogeochemistry. Advances in the understanding of the physiological, behavioral, and metabolic dynamics of HAB-forming organisms from cutting-edge observational techniques will improve our ability to forecast HABs and mitigate their consequences in the future.

In recent years, harmful algal blooms (HABs) have increased in their severity and extent in many parts of the world and pose serious threats to local aquaculture, fisheries, and public health. In many cases, the mechanisms triggering and regulating HAB events remain poorly understood. Using underwater microscopy and Residual Neural Network (ResNet-18) to taxonomically classify imaged organisms, we developed a daily abundance record of four potentially harmful algae (Akashiwo sanguinea, Chattonella spp., Dinophysis spp., and Lingulodinium polyedra) and major grazer groups (ciliates, copepod nauplii, and copepods) from August 2017 to November 2020 at Scripps Institution of Oceanography pier, a coastal location in the Southern California Bight. Random Forest algorithms were used to identify the optimal combination of environmental and ecological variables that produced the most accurate abundance predictions for each taxon. We developed models with high prediction accuracy for A. sanguinea ((Formula presented.)), Chattonella spp. ((Formula presented.)), and L. polyedra ((Formula presented.)), whereas models for Dinophysis spp. showed lower prediction accuracy ((Formula presented.)). Offshore nutricline depth and indices describing climate variability, including El Niño Southern Oscillation, Pacific Decadal Oscillation, and North Pacific Gyre Oscillation, that influence regional-scale ocean circulation patterns and environmental conditions, were key predictor variables for these HAB taxa. These metrics of regional-scale processes were generally better predictors of HAB taxa abundances at this coastal location than the in situ environmental measurements. Ciliate abundance was an important predictor of Chattonella and Dinophysis spp., but not of A. sanguinea and L. polyedra. Our findings indicate that combining regional and local environmental factors with microzooplankton populations dynamics can improve real-time HAB abundance forecasts.

The ecological and oceanographic processes that drive the response of pelagic ocean microbiomes to environmental changes remain poorly understood, particularly in coastal upwelling ecosystems. Here we show that seasonal and interannual variability in coastal upwelling predicts pelagic ocean microbiome diversity and community structure in the Southern California Current region. Ribosomal RNA gene sequencing, targeting prokaryotic and eukaryotic microbes, from samples collected seasonally during 2014-2020 indicate that nitracline depth is the most robust predictor of spatial microbial community structure and biodiversity in this region. Striking ecological changes occurred due to the transition from a warm anomaly during 2014-2016, characterized by intense stratification, to cooler conditions in 2017-2018, representative of more typical upwelling conditions, with photosynthetic eukaryotes, especially diatoms, changing most strongly. The regional slope of nitracline depth exerts strong control on the relative proportion of highly diverse offshore communities and low biodiversity, but highly productive nearshore communities.

Modern in situ digital imaging systems collect vast numbers of images of marine organisms and suspended particles. Automated methods to classify objects in these images – largely supervised machine learning techniques – are now used to deal with this onslaught of biological data. Though such techniques can minimize the human cost of analyzing the data, they also have important limitations. In training automated classifiers, we implicitly program them with an inflexible understanding of the environment they are observing. When the relationship between the classifier and the population changes, the computer's performance degrades, potentially decreasing the accuracy of the estimate of community composition. This limitation of automated classifiers is known as “dataset shift.” Here, we describe techniques for addressing dataset shift. We then apply them to the output of a binary deep neural network searching for diatom chains in data generated by the Scripps Plankton Camera System (SPCS) on the Scripps Pier. In particular, we describe a supervised quantification approach to adjust a classifier's output using a small number of human corrected images to estimate the system error in a time frame of interest. This method yielded an 80% improvement in mean absolute error over the raw classifier output on a set of 41 independent samples from the SPCS. The technique can be extended to adjust the output of multi-category classifiers and other in situ observing systems.

In the face of unprecedented disruption and complexity, the higher education sector appears to be largely underprepared for the projected exodus of senior-level administrators due to retirements and briefer tenures in leadership roles. Given that religiously affiliated institutions account for more than one in five colleges and universities in the United States, it is concerning that relatively few studies have addressed succession planning in this sector, and in Christ-centered higher education in particular. This article provides a review of the literature that has addressed the topic of succession planning and discusses the findings from a single-institution ethnographic case study that explored the culture of succession planning and leader development at Lipscomb University in Nashville, Tennessee. The conceptual framework used in this study was developed through the dissertation research of C. L. Richards in 2009, and is referred to as the "5Cs Model: Strategies for Succession Planning in the Academy." Through a grounded theory study, Richards suggested five strategies leaders should consider as they approach succession planning in academic institutions: "culture," "champions," "communication," "competency-based," and "continuous." The article then discusses succession planning as an effective process that presidents, boards, and senior leaders can use to intentionally develop a cadre of future leaders, highlighting the unique challenges and best practice opportunities of pursuing this strategy, and recommends several implications for practice in Christian higher education.

Purpose: The anatomy of the extraocular rectus muscle insertions is clinically relevant in the field of ophthalmology. This descriptive cadaveric study determines the relative degree orientation of the superior, lateral, and inferior rectus muscles with respect to the medial rectus and investigates the distances between the rectus muscle insertions. Method: Thirty cadavers (50% female, mean age = 81.86 years, SD 12.16) were included for a total of 60 eyes. For each eye, a lateral canthotomy and cantholysis were performed followed by a peritomy. Muscle hooks were then used to access and isolate the rectus muscles. The degree orientation was determined by marking the muscle midpoints at insertion, using the center of the cornea as the vertex, and measuring the angle with the Angle Meter 360 application (© Alexey Kozlov) (Figure 1). The distances between rectus muscles were measured from the same muscle midpoints using calipers. Results: The degree orientations with respect to the medial rectus are displayed in Figure 2 and were as follows: superior rectus (mean = 93.14, SD = 3.04, min. 82.3, max. 100.3), lateral rectus (mean = 180.21, SD = 5.65, min. 170.5, max. 190.6), and inferior rectus (mean = 90.57, SD = 4.47, min. 84.0, max. 98.9). The distances (measured in mm) between rectus muscle midpoints at insertion included medial rectus to inferior rectus (mean = 13.64, SD = 0.54), inferior rectus to lateral rectus (mean = 13.79, SD = 0.75), lateral rectus to superior rectus (mean = 13.54, SD = 0.63), and superior rectus to medial rectus (mean = 13.83, SD = 0.75). The relative distances between the midpoints of the extraocular muscles observed in males versus females showed statistically significant differences in medial rectus to inferior rectus (13.8 vs. 13.5, p = .01), inferior rectus to lateral rectus (14.1 vs. 13.5, p = .03), and superior rectus to medial rectus (14.0 vs. 13.5, p = .04), respectively (Table 1). Conclusion: This is an important study of the extraocular muscle degree orientation performed with an innovative measuring approach. The degree orientation of the insertions relative to the medial rectus may have surgical application in the field of ophthalmology. [ABSTRACT FROM AUTHOR]

The survival outcomes of patients with primary uveal melanomas based on Medicaid status have not been previously discussed in the literature. The Surveillance, Epidemiology, and End Results Medicaid database were utilized to identify patients with primary uveal melanomas diagnosed between 2006 and 2013. The Kaplan–Meier method was utilized to construct 5-year survival curves in adult, non-elderly patients. Log-rank testing was used to determine differences in survival rates, and multivariate Cox proportional hazards modeling was utilized to perform adjusted survival analysis. A total of 1,765 patients were included (Medicaid: 81, non-Medicaid: 1684). A total of 1683 (95.4%) were White. The average age was 51.75 years (SD = 9.5 years). Medicaid patients were more likely to be unmarried, live in a high poverty neighborhood, and live in a rural area (all p <.001). We observed no significant difference in 5-year survival rates between those enrolled in Medicaid (86.6%, 95% CI: 79.1%1–94.7%) and those not enrolled in Medicaid (85.5, 95% CI: 83.8%–87.2%) (p =.80). After controlling for socioeconomic and clinical factors, Medicaid enrollment was not associated with an increased risk of mortality compared to non-Medicaid enrollment. Age (aHR: 1.04, 95% CI: 1.02–1.06, p <.001) and tumor size >10 mm (aHR: 3.04, 95% CI: 1.49–6.21, p =.002) were associated with an increased risk of mortality. Medicaid enrollment was not associated with worse cancer-specific 5-year survival. Further research needs to be elicited to better understand the role of Medicaid enrollment in patients with primary uveal melanoma. [ABSTRACT FROM AUTHOR]

Peripherally inserted central catheters (PICCs) are vital in delivering intravenous therapy. Despite their advantages, PICCs can lead to complications such as catheter exit site bleeding, which can cause patient distress and increase infection risk. This study evaluated the efficacy of StatSeal, a topical haemostatic device, in managing PICC exit site bleeding. StatSeal uses a hydrophilic polymer and potassium ferrate to form a seal, reducing access site bleeding and minimising dressing changes. For this study, Patients were recruited at Frimley Health NHS Foundation Trust; the trial involved 177 patients with StatSeal, and shows that 99% did not require additional dressing changes within the standard 7-day period. The findings demonstrate StatSeal's effectiveness in improving patient outcomes by reducing exit site bleeding and associated complications, enhancing the efficiency of vascular access maintenance and potentially lowering associated healthcare costs. The trial emphasises the importance of innovative solutions such as StatSeal to advance PICC care and improve patient experience. [ABSTRACT FROM AUTHOR]