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Surfzone eddies enhance the dispersion and transport of contaminants, bacteria, and larvae across the nearshore, altering coastal water quality and ecosystem health. During directionally spread wave conditions, vertical vortices (horizontal eddies) are injected near the ends of breaking crests. Energy associated with these eddies may be transferred to larger-scale, low-frequency rotational motions through an inverse energy cascade, consistent with two-dimensional turbulence. However, our understanding of the relationships between the wave conditions and the dynamics and energetics of low-frequency surfzone eddies are largely based on numerical modeling. Here, we test these relationships with remotely sensed and in situ observations from large-scale directional wave basin experiments with varying wave conditions over alongshore-uniform barred bathymetry. Surface velocities derived with particle image velocimetry were employed to assess the spatial scales of low-frequency surfzone eddies and compute structure functions with alongshore velocities. Second-order structure functions for directionally spread waves ( σ θ ≥ 10 °) are consistent with energy flux to larger or smaller length scales, while normally incident, unidirectional waves do not display this behavior. Third-order structure functions suggest that the surfzone flows exhibit a bidirectional energy cascade—a direct cascade to smaller and inverse cascade to larger length scales—during large directional spreads waves ( σ θ ≥ 18 °). However, there is not decisive evidence of an inverse energy cascade for moderate directional spreads ( σ θ = 10 °). Energy flux varies by cross-shore location and increases with increasing directional spread and wave height. Eddy decorrelation length scales weakly depend on wave directional spread. These findings advance our understanding of the dynamics linking wave breaking to large-scale rotational motions that enhance mixing and lead to rip currents, important conduits for cross-shore material exchange. [ABSTRACT FROM AUTHOR]

Off the central California coast near Pt. Sal, a large-amplitude internal bore was observed for 20 h over 10 km cross shore, or 100–10-m water depth (D), and 30 km along coast by remote sensing, 39 in situ moorings, ship surveys, and drifters. The bore is associated with steep isotherm displacements representing a significant fraction of D. Observations were used to estimate bore arrival time tB, thickness h, and bore and nonbore (ambient) temperature difference ΔT, leading to reduced gravity g′. Bore speeds c, estimated from mapped tB, varied from 0.25 to 0.1 m s−1 from D = 50 to 10 m. The h varied from 5 to 35 m, generally decreased with D, and varied regionally along isobath. The bore ΔT varied from 0.75° to 2.15°C. Bore evolution was interpreted from the perspective of a two-layer gravity current. Gravity current speeds U, estimated from the local bore h and g′, compared well to observed bore speeds throughout its cross-shore propagation. Linear internal wave speeds based on various stratification estimates result in larger errors. On average bore thickness h = D/2, with regional variation, suggesting energy saturation. From 50- to 10-m depths, observed bore speeds compared well to saturated gravity current speeds and energetics that depend only on water depth and shelf-wide mean g′. This suggests that this internal bore is the internal wave analog to a saturated surfzone surface gravity bore. Along-coast variations in prebore stratification explain variations in bore properties. Near Pt. Sal, bore Doppler shifting by barotropic currents is observed. [ABSTRACT FROM AUTHOR]

Cross‐shore transport of larvae, pollutants, and sediment between the surf zone and the inner shelf is important for coastal water quality and ecosystems. Rip currents are known to be a dominant pathway for exchange, but the effects of horizontal temperature and salinity gradients are not well understood. Airborne visible and infrared imaging performed on the California coast shows warm and cool plumes driven by rip currents in the surf zone and extending onto the shelf, with temperature differences of approximately 1°C. The airborne imagery and modeled temperatures and tracers indicate that warm plumes exhibit more lateral spreading and transport material in a buoyant near‐surface layer, whereas cool plumes move offshore in a subsurface layer. The average cross‐shore extent of warm plumes at the surface is approximately one surfzone width larger than for cool plumes. Future work may explore the sensitivity of nearshore plumes to density patterns, wave forcing, and bathymetry. Plain Language Summary: Waves and currents in the coastal ocean move plankton, pollutants, nutrients, and sediment between the beach and deeper waters, impacting ecosystems and water quality. Rip currents, strong narrow seaward currents caused by breaking waves, provide a conduit for larvae to move offshore and also carry pollutants away from the beach. One common type of rip current formed in channels interrupting sandbars can sometimes be observed as a plume of brown sediment‐laden water moving offshore. Previous studies of this rip‐current type have assumed that the movement of material by these currents is not affected by differences in the water density (temperature and salinity) between shallower and deeper water. However, thermal (infrared) images taken from an aircraft on the coast of California show that the wave‐breaking region near the beach is often significantly cooler or warmer than the ocean immediately offshore. Rip currents in these images and in numerical simulations appear either as warm plumes, which carry material further offshore and are concentrated at the water surface, or cool plumes, which move material offshore under the surface. The results show that differences in water temperature from the beach to deeper water impact how rip currents move material in the coastal ocean. Key Points: Airborne infrared imagery on the CA coast shows cool and warm plumes driven by rip currents that connect the surf zone to the inner shelfThe surface cross‐shore extent of warm plumes is about one surfzone width larger than that of cool plumes in observations and simulationsModeled cool nearshore plumes entering a stratified shelf subduct, whereas warm plumes extend offshore in a near‐surface layer [ABSTRACT FROM AUTHOR]

The article discusses roundtable conference on teaching Irish history. Topics discussed include transnationalism, history of Ireland and teaching history to undergraduates. Other topics which includes American undergraduates, student surveys and secondary education are also discussed. In addition, great Irish famine is mentioned.

Pyrethroids are commonly used as mosquito adulticides and evolution of resistance to these compounds is a major threat to public health. ‘Knockdown resistance’ to pyrethroids (kdr) is frequently caused by nonsynonymous mutations in the voltage-gated sodium channel transmembrane protein (para) that reduce pyrethroid binding. Early detection of kdr is critical to the development of resistance management strategies in mosquitoes including Aedes aegypti, the most prevalent vector of dengue and yellow fever viruses. Brengues et al. described seven novel mutations in hydrophobic segment 6 of domain II of para in Ae. aegypti. Assays on larvae from strains bearing these mutations indicated reduced nerve sensitivity to permethrin inhibition. Two of these occurred in codons Iso1011 and Val1016 in exons 20 and 21 respectively. A transition in the third position of Iso1011 encoded a Met1011 replacement and a transversion in the second position of Val1016 encoded a Gly1016 replacement. We have screened this same region in 1318 mosquitoes in 32 additional strains; 30 from throughout Latin America. While the Gly1016 allele was never detected in Latin America, we found two new mutations in these same codons. A transition in the first position of codon 1011 encodes a Val replacement while a transition in the first position of codon 1016 encodes an Iso replacement. We developed PCR assays for these four mutations that can be read either on an agarose gel or as a melting curve. Selection experiments, one with deltamethrin on a field strain from Santiago de Cuba and another with permethrin on a strain from Isla Mujeres, Mexico rapidly increased the frequency of the Iso1016 allele. Bioassays of F3 offspring arising from permethrin susceptible Val1016 homozygous parents and permethrin resistant Iso1016 homozygous parents show that Iso1016 segregates as a recessive allele in conferring kdr. Analysis of segregation between alleles at the 1011 and 1016 codons in the F3 showed a high rate of recombination even though the two codons are only separated by a ~250 bp intron. The tools and information presented provide a means for early detection and characterization of kdr that is critical to the development of strategies for resistance management. [ABSTRACT FROM AUTHOR]

Background: Conventional wisdom holds that hyperextension of the metacarpophalangeal joint of the thumb is secondary to degenerative subluxation of the trapeziometacarpal joint as occurs in osteoarthritis. We propose that a hypermobile metacarpophalangeal joint may have a causative role in the development of primary osteoarthritis at the base of the thumb by concentrating forces on the palmar aspect of the trapeziometacarpal joint.Methods: Twenty fresh-frozen cadaveric forearm specimens were obtained post mortem from donors with no history of connective-tissue disease. Each specimen was categorized by its passive range of metacarpophalangeal joint motion. Testing was conducted with Fuji ultra-low-pressure-sensitive film while the hand was in the lateral-pinch mode with the metacarpophalangeal joint in each of the following positions: unrestrained, pinned in neutral, pinned in 30 degrees of flexion, and pinned in maximal hyperextension. Quantitative analysis of the trapezial contact surface at each of the metacarpophalangeal joint positions was performed, and the center of pressure was determined. Each specimen was then classified according to the extent of arthritic disease (nonarthritic, moderately arthritic, or affected by end-stage arthritis).Results: In specimens affected by end-stage osteoarthritis, the center of pressure on the trapeziometacarpal joint moved dorsally by 56.8% of the length of the trapezial surface with metacarpophalangeal joint flexions of 30 degrees (p < 0.01), whereas the corresponding values were 28.2% and 40.9% in the hyperextended and neutral metacarpophalangeal joint positions, respectively. In specimens with moderate osteoarthritis, 30 degrees of metacarpophalangeal joint flexion also produced the most dorsal trapeziometacarpal center of pressure (44.8%); however, this center of pressure was not significantly different from the centers of pressure at the other metacarpophalangeal joint positions. In nonarthritic specimens, the center of pressure was again significantly more dorsal with metacarpophalangeal joint flexion of 30 degrees than it was at the other positions (p < 0.01).Conclusion: Metacarpophalangeal joint flexion effectively unloaded the most palmar surfaces of the trapeziometacarpal joint regardless of the presence or severity of arthritic disease in this joint. [ABSTRACT FROM AUTHOR]

Purpose LVAD exchange is an accepted treatment for LVAD complications but long-term results are poorly understood. We examined survival and re-thrombosis rate in patients after pump exchange Methods All patients undergoing LVAD exchange at our institution from Jan 2010 to Feb 2018 were retrospectively reviewed. Indications for exchange were pump thrombosis, driveline fracture, and device infection. Survival and freedom from LVAD-related complications were assessed by Kaplan-Meier method. Results Twenty-one patients were included, all underwent axial continuous-flow pump exchange: 14 patients (67%) for pump thrombosis, 5 patients (24%) for driveline fracture, and 2 patients (10%) for device infection. Basic characteristics of patients are presented in Table 1. Survival for all patients was 86±8% at one year and 70±39% at two years (Figure 1A). Amongst patients with pump thrombosis 14.3% died peri-operatively, 43% had recurrent thrombosis after a median of 5.7 months (freedom from hospital death and recurrent thrombosis is shown in Figure 1B). Amongst 6 patients with recurrent thrombosis 2 died during follow up, 1 underwent transplantation, 1 had a second exchange, 1 was defunctionalized and 1 remains on support. Survival at one year in this group was 85±10%, and 55±18% at two years. Conclusion Survival after LVAD exchange compares well with published results after primary LVAD implantation. However, recurrence of thrombosis was common among patients who required a LVAD exchange due to pump thrombosis and survival was less favorable. In this sub-group strong consideration should be given to alternative strategies to avoid recurrent complications. [ABSTRACT FROM AUTHOR]

Purpose To investigate the outcome of patients in refractory cardiogenic shock who required VA ECMO as a bridge to durable LVAD Methods This is a retrospective review of all adult INTERMACS profile 1 patients who underwent LVAD implantation at our institution between 01/01/2015 and 12/31/2017. The outcomes of patients who were bridged with VA ECMO (ECMO group) were compared with those without bridging (non-ECMO group). Results Out of 27 patients, 16 were bridged with VA ECMO. Basic characteristics are presented in Table 1. After the LVAD implantation, patients in the ECMO group experienced more right ventricular failure requiring temporary RVAD (75% vs. 27%, P = 0.014) and more postoperative surgical bleeding (75% vs. 36%, P = 0.045). Hospital mortality was 25% in ECMO and 18% in non-ECMO group (P = 0.675). Of the hospital survivors, 8 were transplanted, 4 recovered, one patient underwent pump exchange and three are still on support. One-year survival for ECMO group was 56 ±18% versus 47 ±20% in non-ECMO group (Figure 1A). Freedom from infection (Figure 1B), neurologic dysfunction (Figure 1C) and device malfunction (Figure 1D) was 47 ±13%, 65 ±20% and 79 ±11% in ECMO group and 44 ±18%, 37 ±22% and 78 ±14% in non-ECMO group. Conclusion Patients in refractory cardiogenic shock have acceptable post LVAD outcome when bridged with percutaneous VA ECMO. Despite significantly higher rate of postoperative surgical bleeding and the need for biventricular support, both overall survival and LVAD-associated complications are comparable to non-ECMO bridged INTERMACS profile 1 LVAD recipients. [ABSTRACT FROM AUTHOR]

Coral reefs are highly important ecosystems providing habitat for biodiverse marine life and numerous benefits for humans. However they face immense risks from climate change. To date, Representative Concentration Pathway (RCP) climate models have aided global discussions on possible policy responses to adapt to change, but tailored climate projections at a useful scale for environmental managers are often prohibitively expensive to produce. Our research addresses this problem by presenting a novel type of collaborative, participatory research that integrates 1) site specific climate metrics from the Community Earth System Model version 2 large ensemble (CESM2-LE), 2) ecosystem response models to determine Degree Heating Months and coral bleaching impacts, and 3) collaborative social science data from environmental manager engagement to see how managers in one of the most visited marine sanctuaries in the world are enacting adaptive governance, stewarding reefs through climate impacts of the future. Our research is valuable to decision-makers seeking opportunities for innovative policy responses to climate impacts focused on experimentation and dialogue., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Kelly Dunning reports financial support was provided by National Center for Atmospheric Research. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

The appropriate diagnosis and management of cryptogenic stroke and transient ischemic attack (TIA) is challenging and requires multidisciplinary involvement. Joint societal guidelines exist to guide the comprehensive evaluation of these entities. This study aimed to implement a standardized multidisciplinary diagnostic algorithm for cryptogenic stroke/TIA. We performed a retrospective analysis of patients admitted to the largest regional military healthcare center with stroke or TIA considered to be cryptogenic at the time of discharge. We abstracted baseline demographics and rates of extra- and intracranial imaging, transthoracic and transesophageal echocardiography, and event monitor orders at the time of discharge. The incidence of event monitor results at 30 days and six months were included. A diagnostic algorithm for evaluation of cryptogenic stroke/TIA was created and disseminated hospital-wide using increased compliance with neuroimaging, echocardiography, and cardiac rhythm monitoring as primary endpoints for our intervention. Post-intervention data abstraction revealed similar rates of extra- and intracranial imaging, but significantly greater rates of transthoracic echocardiography (70% vs. 87%, p 0.0073), inclusion of agitated saline study (41% vs. 65%, p 0.0024), and event monitors ordered at discharge (18% vs. 35%, p 0.0045). At six months there was a higher rate of event monitors obtained (24% vs. 45%, p 0.001). Our study showed implementation of an evidence-based diagnostic algorithm for evaluation of cryptogenic stroke/TIA increases appropriate use of echocardiography and event monitoring., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Hull et al.)

Exchange of material across the nearshore region, extending from the shoreline to a few kilometers offshore, determines the concentrations of pathogens and nutrients near the coast and the transport of larvae, whose cross-shore positions influence dispersal and recruitment. Here, we describe a framework for estimating the relative importance of cross-shore exchange mechanisms, including winds, Stokes drift, rip currents, internal waves, and diurnal heating and cooling. For each mechanism, we define an exchange velocity as a function of environmental conditions. The exchange velocity applies for organisms that keep a particular depth due to swimming or buoyancy. A related exchange diffusivity quantifies horizontal spreading of particles without enough vertical swimming speed or buoyancy to counteract turbulent velocities. This framework provides a way to determinewhich processes are important for cross-shore exchange for a particular study site, time period, and particle behavior.

Introduction: The Carpentier-Edwards PERIMOUNT Magna Ease valve is a third-generation bioprosthesis for aortic valve replacement (AVR). This is a postapproval study reporting on its 8-year outcomes., Methods: Adults undergoing AVR with the Magna Ease valve between October 2007 and December 2012 were enrolled for this prospective, nonrandomized, single-arm, and multicenter study. Assessments occurred preoperatively, at hospital discharge, 6 months, 1 year, and annually thereafter for up to 8 years. Outcomes included safety endpoints, hemodynamic performance, and New York Heart Association (NYHA) functional class., Results: Of the 258 study patients, 67.5% were in NYHA Class I or II, and 32.5% were in NYHA Class III or IV at baseline. Concomitant procedures were performed in 44.2%. Total follow-up was 1597.6 patient-years, and median follow-up was 7 years (interquartile range: 5.5-8.0 years). Eight years following AVR, the functional class remained improved from baseline with 93.9% in NYHA Class I/II and 6.1% in NYHA Class III; 38 deaths had occurred, 8 of which were valve related; freedom from all-cause mortality was 80.7% (95% confidence intervals: 74.9, 86.4); freedom from valve-related mortality was 95.8% (92.8, 98.8); freedom from reintervention, explant, major bleeding events, and structural valve deterioration was 89.8% (85.1, 94.6), 94.8% (91.7, 97.9), 85.1% (80.0, 90.1), and 90.1% (84.7, 95.4), respectively; effective orifice area was 1.5 ± 0.5 cm 2 , the mean gradient was 14.8 ± 8.3 mmHg, and 88.6% of patients had no or trivial aortic regurgitation., Conclusions: This study demonstrated satisfactory safety and sustained hemodynamic and functional improvements at 8 years following AVR with the Magna Ease valve., (© 2022 The Authors. Journal of Cardiac Surgery published by Wiley Periodicals LLC.)

Background: The personal statement is an integral part of a residency application but little guidance exists for medical students about what content to include., Objective: We use the framework of isomorphism, the process by which institutions model themselves after one another, to understand what internal medicine program directors (PDs) and associate program directors (APDs) recommend be included in the personal statement and how programs use personal statements in their selection of applicants to interview and rank., Methods: Semi-structured phone interviews were conducted between August and October 2020 with 13 academic PDs and APDs, who were selected for participation based on program size and geographic location. Interviews were recorded, transcribed, and coded using content analysis., Results: Effective personal statements should be well-written, present unique information, and demonstrate fit with a residency program. PDs and APDs recommended against expressing lack of interest in a program or highlighting negative personal characteristics. PDs and APDs used personal statements to distinguish between applicants and noted that personal statements help programs form an impression of the applicant. Consensus among PDs and APDs about what personal statements should include and how they are used indicates that isomorphism influences the match process., Conclusions: Our study found that the personal statement is a valued part of the residency application when it includes unique attributes and reveals personal values that align with that of the program. Additionally, PDs and APDs noted that when applicants highlight their unique characteristics, it can help distinguish themselves from others., Competing Interests: Conflict of interest: The authors declare they have no competing interests.

Background: Postcardiotomy extracorporeal membrane oxygenation (PC-ECMO) represents a unique subset of critically ill patients, with a paucity of data regarding long-term survival and correlated characteristics. We present a retrospective cohort of PC-ECMO patients, with outcomes at 1 and 3 years., Methods: Data were collected retrospectively for all patients requiring ECMO within 72 hours of an index cardiac operation (excluding assist devices and transplants). Primary outcomes were the ability to wean from ECMO, hospital survival, and long-term survival., Results: Thirty-one patients required PC-ECMO, representing a total of 172 days of ECMO support. Overall survival data were the ability to wean 58%, hospital survival 52%, 1-month survival 42%. The estimated 12- and 36-month survival for all PC-ECMO patients was 35% and 29%, respectively. Twelve and 36-month survival for all hospital survivors was 62% and 56%. Operative times, the Society of Thoracic Surgeons risk scores, type of operation, open chest status, hemorrhage, and cannulation location, and timing were all compared. Centrally cannulated patients were more likely to wean from ECMO (83% vs 44%; P = .03), and survive hospitalization (75% vs 36%; P = .04) and trended toward long-term survival benefit (67% vs 33%; P = .06). Otherwise, no statistically significant relationships were observed., Conclusions: Central cannulation may provide benefits in the postcardiotomy patient, compared to peripheral strategies. Twelve and 36-month survival for all PC-ECMO patients was 35% and 29%. For hospital survivors, 12 and 36-month survival 62% 56% at 36. These data support PC-ECMO as a reasonable salvage strategy, with midterm survival comparable to other surgically treated diseases., (© 2020 Wiley Periodicals LLC.)