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Whereas recruitment success for many fisheries depends on coincident timing of larvae with abundance peaks of their prey, less can be more in the tropical/subtropical spawning areas of bluefin tunas if lower but steady food resources are offset by reduced larval vulnerability to pelagic predators. To understand larval habitat characteristics for Southern Bluefin Tuna (SBT), we quantified microbial community carbon flows based on growth and grazing rates from depth profiles of dilution incubations and carbon biomass assessments from microscopy and flow cytometry (FCM) during their peak spawning off NW Australia (Indian Ocean) in February 2022. Two Chla-based estimates of phytoplankton production gave differing offsets due to cycling or mixotrophy, exceeding 14C net community production on average (677 ± 98 versus 447 ± 43 mg C m−2 d−1). Productivity was higher than in the Gulf of Mexico spawning area for Atlantic Bluefin Tuna but less than similar studies of oceanic upwelling regions. Microzooplankton grazing averaged 482 ± 63 mg C m−2 d−1 (71 ± 13 % of production). Two measurement variables for Prochlorococcus gave average production and grazing rates of 282 ± 36 and 248 ± 32 mg C m−2 d−1 (86 ± 6 % grazed). Prochlorococcus comprised almost half of production and grazing fluxes in the upper (0–25 m) euphotic zone where SBT larvae reside. Prochlorococcus declined and eukaryotic phytoplankton and heterotrophic bacteria increased in relative importance in the lower euphotic zone. These results describe relatively classic open-ocean oligotrophic conditions as the food web base for nutritional flows to SBT larvae. 

Background Team leadership during medical emergencies like cardiac arrest resuscitation is cognitively demanding, especially for trainees. These cognitive processes remain poorly characterized due to measurement challenges. Using virtual reality simulation, this study aimed to elucidate and compare communication and cognitive processes-such as decision-making, cognitive load, perceived pitfalls, and strategies-between expert and novice code team leaders to inform strategies for accelerating proficiency development. Methods A simulation-based mixed methods approach was utilized within a single large academic medical center, involving twelve standardized virtual reality cardiac arrest simulations. These 10- to 15-minutes simulation sessions were performed by seven experts and five novices. Following the simulations, a cognitive task analysis was conducted using a cued-recall protocol to identify the challenges, decision-making processes, and cognitive load experienced across the seven stages of each simulation. Results The analysis revealed 250 unique cognitive processes. In terms of reasoning patterns, experts used inductive reasoning, while novices tended to use deductive reasoning, considering treatments before assessments. Experts also demonstrated earlier consideration of potential reversible causes of cardiac arrest. Regarding team communication, experts reported more critical communications, with no shared subthemes between groups. Experts identified more teamwork pitfalls, and suggested more strategies compared to novices. For cognitive load, experts reported lower median cognitive load (53) compared to novices (80) across all stages, with the exception of the initial presentation phase. Conclusions The identified patterns of expert performance — superior teamwork skills, inductive clinical reasoning, and distributed cognitive strategiesn — can inform training programs aimed at accelerating expertise development. 

Surrogate selection is an experimental design that without sequencing any DNA can restrict a sample of cells to those carrying certain genomic mutations. In immunological disease studies, this design may provide a relatively easy approach to enrich a lymphocyte sample with cells relevant to the disease response because the emergence of neutral mutations associates with the proliferation history of clonal subpopulations. A statistical analysis of clonotype sizes provides a structured, quantitative perspective on this useful property of surrogate selection. Our model specification couples within-clonotype birth-death processes with an exchangeable model across clonotypes. Beyond enrichment questions about the surrogate selection design, our framework enables a study of sampling properties of elementary sample diversity statistics; it also points to new statistics that may usefully measure the burden of somatic genomic alterations associated with clonal expansion. We examine statistical properties of immunological samples governed by the coupled model specification, and we illustrate calculations in surrogate selection studies of melanoma and in single-cell genomic studies of T cell repertoires. 

Abstract Robot-assisted surgeries (RAS) have an extremely steep learning curve. Because of this, surgeons have created many methods to practice RAS outside the operating room. These training models usually include animal or plastic models; however, extended reality simulators have recently been introduced into surgical training programs. This systematic review and meta-analysis was conducted to determine if extended reality simulators can improve the performance of robotic novices and how their performance compares to the conventional training of surgeons on surgical robots. Using the PRISMA 2020 guidelines, a systematic review was performed searching PubMed, Embase, Web of Science, and Cochrane library for studies that compared the performance of robotic novices that received no additional training, trained with extended reality, or trained with inanimate physical simulators (conventional additional training). Articles that gauged performance using GEARS or time to complete measurements were included, while articles that did not make this comparison were excluded. A meta-analysis was performed on the 15 studies found using SPSS to compare the performance outcomes of the novices after training. Robotic novices trained with extended reality simulators showed a statistically significant improvement in time to complete (Cohen’s d = −0.95,p = 0.02) compared to those with no additional training. Extended reality training also showed no statistically significant difference in performance in time to complete (Cohen’s d = 0.65,p = 0.14) or GEARS scores (Cohen’s d = −0.093, p = 0.34) compared to robotic novices trained with conventional models. This meta-analysis seeks to determine if extended reality simulators translate complex skills to surgeons in a low-cost and low-risk environment. 

Sudden onsets in the visual periphery elicit reflexive shifts of covert exogenous spatial attention. Here, we asked: are the behavioral effects of such an irrelevant exogenous cue modulated by implicit knowledge about the probability of the cue’s presence? Participants discriminated the orientation of a visual target that was preceded, on some trials, by an abrupt-onset task-irrelevant disk (exogenous cue). A color at fixation (red or green) signaled the probability that a cue would appear (0.8, “high- probability”, or 0.2, “low-probability”). When presented, this cue flashed briefly in the periphery, either near the target (valid cue) or non-target stimulus (invalid cue, equally likely). We used a speed- accuracy tradeoff (SAT) procedure to vary the time given for participants to process the stimuli before responding. We found that low-probability cues generated significantly larger cueing effects (discrimination accuracy, valid–invalid) than high-probability cues, but only when responses were made early in the accumulation of visual information (i.e., under strict time pressure). Both the directionality and temporal dynamics of these results were replicated across a series of online studies. Thus, expectations about an exogenous cue’s presence or absence have a significant yet transient impact on its ability to direct the reflexive allocation of covert exogenous spatial attention. 

Reliably identifying and verifying subjects remains integral to computer system security. Various novel authentication techniques, such as biometric authentication systems, have been developed in recent years. This article provides a detailed review of keystroke-based authentication systems and their applications. Keystroke dynamics is a behavioral biometric that is emerging as an important tool for cybersecurity as it promises to be nonintrusive and cost-effective. In addition, no additional hardware is required, making it convenient to deploy. This survey covers novel keystroke datasets, state-of-the-art keystroke authentication algorithms, keystroke authentication on touch screen and mobile devices, and various prominent applications of such techniques beyond authentication. The article covers all the significant aspects of keystroke dynamics and can be considered a reference for future researchers in this domain. The article includes a discussion of the latest keystroke datasets, providing researchers with an up-to-date resource for analysis and experimentation. In addition, this survey covers the state-of-the-art algorithms adopted within this domain, offering insights into the cutting-edge techniques utilized for keystroke analysis. Moreover, this article explains the diverse applications of keystroke dynamics, particularly focusing on security, verification, and identification uses. Beyond these crucial areas, we mention additional applications where keystroke dynamics can be applied, broadening the scope of understanding regarding its potential impact across various domains. Unlike previous survey articles, which typically concentrate on specific aspects of keystroke dynamics, our comprehensive analysis presents all relevant areas within this field. By introducing discussions on the latest advances, we provide readers with a thorough understanding of the current landscape and emerging trends in keystroke dynamics research. Furthermore, this article presents a summary of future research opportunities, highlighting potential areas for exploration and development within the realm of keystroke dynamics. This forward-looking perspective aims to inspire further inquiry and innovation, guiding the trajectory of future studies in this dynamic field.