Cellular adaptations leading to coral fragment attachment on artificial substrates in Acropora millepora (Am-CAM).

Reproductive propagation by asexual fragmentation in the reef-building coral Acropora millepora depends on (1) successful attachment to the reef substrate through modification of soft tissues and (2) a permanent bond with skeletal encrustation. Despite decades of research examining asexual propagation in corals, the initial response, cellular reorganisation, and development leading to fragment substrate attachment via a newly formed skeleton has not been documented in its entirety. Here, we establish the first "coral attachment model" for this species ("Am-CAM") by developing novel methods that allow correlation of fluorescence and electron microscopy image data with in vivo microscopic time-lapse imagery. This multi-scale imaging approach identified three distinct phases involved in asexual propagation: (1) the contact response of the coral fragment when contact with the substrate, followed by (2) fragment stabilisation through anchoring by the soft tissue, and (3) formation of a "lappet-like appendage" structure leading to substrate bonding of the tissue for encrustation through the onset of skeletal calcification. In developing Am-CAM, we provide new biological insights that can enable reef researchers, managers and coral restoration practitioners to begin evaluating attachment effectiveness, which is needed to optimise species-substrate compatibility and achieve effective outplanting.

Development and validation of a prognostic 40-day mortality risk model among hospitalized patients with COVID-19.

OBJECTIVES: The development of a prognostic mortality risk model for hospitalized COVID-19 patients may facilitate patient treatment planning, comparisons of therapeutic strategies, and public health preparations. METHODS: We retrospectively reviewed the electronic health records of patients hospitalized within a 13-hospital New Jersey USA network between March 1, 2020 and April 22, 2020 with positive polymerase chain reaction results for SARS-CoV-2, with follow-up through May 29, 2020. With death or hospital discharge by day 40 as the primary endpoint, we used univariate followed by stepwise multivariate proportional hazard models to develop a risk score on one-half the data set, validated on the remainder, and converted the risk score into a patient-level predictive probability of 40-day mortality based on the combined dataset. RESULTS: The study population consisted of 3123 hospitalized COVID-19 patients; median age 63 years; 60% were men; 42% had >3 coexisting conditions. 713 (23%) patients died within 40 days of hospitalization for COVID-19. From 22 potential candidate factors 6 were found to be independent predictors of mortality and were included in the risk score model: age, respiratory rate ≥25/minute upon hospital presentation, oxygenation <94% on hospital presentation, and pre-hospital comorbidities of hypertension, coronary artery disease, or chronic renal disease. The risk score was highly prognostic of mortality in a training set and confirmatory set yielding in the combined dataset a hazard ratio of 1.80 (95% CI, 1.72, 1.87) for one unit increases. Using observed mortality within 20 equally sized bins of risk scores, a predictive model for an individual's 40-day risk of mortality was generated as -14.258 + 13.460*RS + 1.585*(RS-2.524)^2-0.403*(RS-2.524)^3. An online calculator of this 40-day COVID-19 mortality risk score is available at www.HackensackMeridianHealth.org/CovidRS. CONCLUSIONS: A risk score using six variables is able to prognosticate mortality within 40-days of hospitalization for COVID-19. TRIAL REGISTRATION: Clinicaltrials.gov Identifier: NCT04347993.

Substrate stabilisation and small structures in coral restoration: State of knowledge, and considerations for management and implementation.

Coral reef ecosystems are under increasing pressure from local and regional stressors and a changing climate. Current management focuses on reducing stressors to allow for natural recovery, but in many areas where coral reefs are damaged, natural recovery can be restricted, delayed or interrupted because of unstable, unconsolidated coral fragments, or rubble. Rubble fields are a natural component of coral reefs, but repeated or high-magnitude disturbances can prevent natural cementation and consolidation processes, so that coral recruits fail to survive. A suite of interventions have been used to target this issue globally, such as using mesh to stabilise rubble, removing the rubble to reveal hard substrate and deploying rocks or other hard substrates over the rubble to facilitate recruit survival. Small, modular structures can be used at multiple scales, with or without attached coral fragments, to create structural complexity and settlement surfaces. However, these can introduce foreign materials to the reef, and a limited understanding of natural recovery processes exists for the potential of this type of active intervention to successfully restore local coral reef structure. This review synthesises available knowledge about the ecological role of coral rubble, natural coral recolonisation and recovery rates and the potential benefits and risks associated with active interventions in this rapidly evolving field. Fundamental knowledge gaps include baseline levels of rubble, the structural complexity of reef habitats in space and time, natural rubble consolidation processes and the risks associated with each intervention method. Any restoration intervention needs to be underpinned by risk assessment, and the decision to repair rubble fields must arise from an understanding of when and where unconsolidated substrate and lack of structure impair natural reef recovery and ecological function. Monitoring is necessary to ascertain the success or failure of the intervention and impacts of potential risks, but there is a strong need to specify desired outcomes, the spatial and temporal context and indicators to be measured. With a focus on the Great Barrier Reef, we synthesise the techniques, successes and failures associated with rubble stabilisation and the use of small structures, review monitoring methods and indicators, and provide recommendations to ensure that we learn from past projects.

Direct Write of 3D Nanoscale Mesh Objects with Platinum Precursor via Focused Helium Ion Beam Induced Deposition.

The next generation optical, electronic, biological, and sensing devices as well as platforms will inevitably extend their architecture into the 3rd dimension to enhance functionality. In focused ion beam induced deposition (FIBID), a helium gas field ion source can be used with an organometallic precursor gas to fabricate nanoscale structures in 3D with high-precision and smaller critical dimensions than focused electron beam induced deposition (FEBID), traditional liquid metal source FIBID, or other additive manufacturing technology. In this work, we report the effect of beam current, dwell time, and pixel pitch on the resultant segment and angle growth for nanoscale 3D mesh objects. We note subtle beam heating effects, which impact the segment angle and the feature size. Additionally, we investigate the competition of material deposition and sputtering during the 3D FIBID process, with helium ion microscopy experiments and Monte Carlo simulations. Our results show complex 3D mesh structures measuring ~300 nm in the largest dimension, with individual features as small as 16 nm at full width half maximum (FWHM). These assemblies can be completed in minutes, with the underlying fabrication technology compatible with existing lithographic techniques, suggesting a higher-throughput pathway to integrating FIBID with established nanofabrication techniques.

Structural Competency: Curriculum for Medical Students, Residents, and Interprofessional Teams on the Structural Factors That Produce Health Disparities.

Introduction: Research on disparities in health and health care has demonstrated that social, economic, and political factors are key drivers of poor health outcomes. Yet the role of such structural forces on health and health care has been incorporated unevenly into medical training. The framework of structural competency offers a paradigm for training health professionals to recognize and respond to the impact of upstream, structural factors on patient health and health care. Methods: We report on a brief, interprofessional structural competency curriculum implemented in 32 distinct instances between 2015 and 2017 throughout the San Francisco Bay Area. In consultation with medical and interprofessional education experts, we developed open-ended, written-response surveys to qualitatively evaluate this curriculum's impact on participants. Qualitative data from 15 iterations were analyzed via directed thematic analysis, coding language, and concepts to identify key themes. Results: Three core themes emerged from analysis of participants' comments. First, participants valued the curriculum's focus on the application of the structural competency framework in real-world clinical, community, and policy contexts. Second, participants with clinical experience (residents, fellows, and faculty) reported that the curriculum helped them reframe how they thought about patients. Third, participants reported feeling reconnected to their original motivations for entering the health professions. Discussion: This structural competency curriculum fills a gap in health professional education by equipping learners to understand and respond to the role that social, economic, and political structural factors play in patient and community health.

Early Childhood Oral Health and Nutrition in Urban and Rural Nepal.

Globalization and urbanization in Nepal have driven a nutritional transition from an agricultural-based diet to an ultra-processed, sugary diet. This study assessed the nutrition and oral health of 836 children age 6 months to 6 years and their families in rural and urban Nepal. Mothers were interviewed about maternal-child oral health and nutrition, and children received dental exams and height and weight measurements. Analyses utilized SPSS statistical software. Most families lived within a 5-minute walk to a store selling ultra-processed snacks and sugary drinks. While most mothers knew sweets caused tooth decay, half of the children were given sweets daily, and 58.2% of children had dental caries. Caries began in the first 2 years and increased in prevalence and severity to age 6, when 74.3% had caries and 20% experienced mouth pain. Despite greater health knowledge and resources among urban mothers, urban children's increased access to junk food and frequency of consumption was associated with higher prevalence and severity of caries compared to rural children. Severe caries was associated with malnutrition, especially in rural children. Preventive strategies are needed in early childhood to incorporate nutrition and oral health education and dental care into maternal-child health services, and develop policies to prohibit the sale of junk food around schools.

Growth and nanomechanical characterization of nanoscale 3D architectures grown via focused electron beam induced deposition.

Nanomechanical measurements of platinum-carbon 3D nanoscale architectures grown via focused electron beam induced deposition (FEBID) were performed using a nanoindentation system in a scanning electron microscope (SEM) for simultaneous in situ imaging. Compression tests were used to estimate the modulus of the platinum-carbon deposits to be in the range of 8.6-10.5 GPa. Cantilever arm bend tests resulted in a modulus estimation of 15.6 GPa. Atomic layer deposition was used to conformally coat FEBID structures with a thin film of Al2O3, which strengthened the structures and increased the measured modulus. Cycled load-displacement testing at various load rates of nano-truss structures was also performed, demonstrating a viscoelastic response in the FEBID material. Finally, load-displacement tests of a variety of 3-dimensional nanoarchitectures with and without Al2O3 coatings were measured.

3D Nanoprinting via laser-assisted electron beam induced deposition: growth kinetics, enhanced purity, and electrical resistivity.

We investigate the growth, purity, grain structure/morphology, and electrical resistivity of 3D platinum nanowires synthesized via electron beam induced deposition with and without an in situ pulsed laser assist process which photothermally couples to the growing Pt-C deposits. Notably, we demonstrate: 1) higher platinum concentration and a coalescence of the otherwise Pt-C nanogranular material, 2) a slight enhancement in the deposit resolution and 3) a 100-fold improvement in the conductivity of suspended nanowires grown with the in situ photothermal assist process, while retaining a high degree of shape fidelity.

Direct-Write 3D Nanoprinting of Plasmonic Structures.

During the past decade, significant progress has been made in the field of resonant optics ranging from fundamental aspects to concrete applications. While several techniques have been introduced for the fabrication of highly defined metallic nanostructures, the synthesis of complex, free-standing three-dimensional (3D) structures is still an intriguing, but so far intractable, challenge. In this study, we demonstrate a 3D direct-write synthesis approach that addresses this challenge. Specifically, we succeeded in the direct-write fabrication of 3D nanoarchitectures via electron-stimulated reactions, which are applicable on virtually any material and surface morphology. By that, complex 3D nanostructures composed of highly compact, pure gold can be fabricated, which reveal strong plasmonic activity and pave the way for a new generation of 3D nanoplasmonic architectures that can be printed on-demand.

Ethics Simulation in Global Health Training (ESIGHT).

INTRODUCTION: Many health care trainees and providers have reported feeling unprepared for the ethical dilemmas they faced while practicing in global health. Simulation is an effective teaching modality in the training of health care professionals. This resource describes the development, implementation, and assessment of an innovative simulation training program for global health ethics. METHODS: We conducted simulation training with trainees and professionals from various health care disciplines. After a didactic component in which general ethical principles were introduced, participants acted as either lead or observer in four simulations representing different ethical challenges. Participants interacted with simulated patients within a set designed to resemble a resource-constrained environment. Data on the participants' experiences and evaluations of the program's effectiveness were collected through pre-/postsession surveys and focus groups. RESULTS: All 53 participants (100%) agreed that the simulations "effectively highlighted ethical dilemmas I could face abroad," and 98% agreed that the content "was useful in my preparation for an international elective." Responses from surveys and focus groups stressed the importance of the realistic and emotional nature of the simulation in increasing confidence and preparedness, as well as a preference for simulation as the modality for teaching global health ethics. DISCUSSION: Simulation for global health ethics training can help to raise awareness of the complex ethical challenges one may face abroad. Incorporating simulation training within broader global health curricula can improve trainee preparedness and confidence in appropriately and effectively identifying, strategizing, and navigating through ethical dilemmas in the field.

Laser-Assisted Focused He+ Ion Beam Induced Etching with and without XeF2 Gas Assist.

Focused helium ion (He+) milling has been demonstrated as a high-resolution nanopatterning technique; however, it can be limited by its low sputter yield as well as the introduction of undesired subsurface damage. Here, we introduce pulsed laser- and gas-assisted processes to enhance the material removal rate and patterning fidelity. A pulsed laser-assisted He+ milling process is shown to enable high-resolution milling of titanium while reducing subsurface damage in situ. Gas-assisted focused ion beam induced etching (FIBIE) of Ti is also demonstrated in which the XeF2 precursor provides a chemical assist for enhanced material removal rate. Finally, a pulsed laser-assisted and gas-assisted FIBIE process is shown to increase the etch yield by ∼9× relative to the pure He+ sputtering process. These He+ induced nanopatterning techniques improve material removal rate, in comparison to standard He+ sputtering, while simultaneously decreasing subsurface damage, thus extending the applicability of the He+ probe as a nanopattering tool.

Simulation-Guided 3D Nanomanufacturing via Focused Electron Beam Induced Deposition.

Focused electron beam induced deposition (FEBID) is one of the few techniques that enables direct-write synthesis of free-standing 3D nanostructures. While the fabrication of simple architectures such as vertical or curving nanowires has been achieved by simple trial and error, processing complex 3D structures is not tractable with this approach. In part, this is due to the dynamic interplay between electron-solid interactions and the transient spatial distribution of absorbed precursor molecules on the solid surface. Here, we demonstrate the ability to controllably deposit 3D lattice structures at the micro/nanoscale, which have received recent interest owing to superior mechanical and optical properties. A hybrid Monte Carlo-continuum simulation is briefly overviewed, and subsequently FEBID experiments and simulations are directly compared. Finally, a 3D computer-aided design (CAD) program is introduced, which generates the beam parameters necessary for FEBID by both simulation and experiment. Using this approach, we demonstrate the fabrication of various 3D lattice structures using Pt-, Au-, and W-based precursors.

In Situ Mitigation of Subsurface and Peripheral Focused Ion Beam Damage via Simultaneous Pulsed Laser Heating.

Focused helium and neon ion (He(+)/Ne(+)) beam processing has recently been used to push resolution limits of direct-write nanoscale synthesis. The ubiquitous insertion of focused He(+)/Ne(+) beams as the next-generation nanofabrication tool-of-choice is currently limited by deleterious subsurface and peripheral damage induced by the energetic ions in the underlying substrate. The in situ mitigation of subsurface damage induced by He(+)/Ne(+) ion exposures in silicon via a synchronized infrared pulsed laser-assisted process is demonstrated. The pulsed laser assist provides highly localized in situ photothermal energy which reduces the implantation and defect concentration by greater than 90%. The laser-assisted exposure process is also shown to reduce peripheral defects in He(+) patterned graphene, which makes this process an attractive candidate for direct-write patterning of 2D materials. These results offer a necessary solution for the applicability of high-resolution direct-write nanoscale material processing via focused ion beams.

Inert Gas Enhanced Laser-Assisted Purification of Platinum Electron-Beam-Induced Deposits.

Electron-beam-induced deposition patterns, with composition of PtC5, were purified using a pulsed laser-induced purification reaction to erode the amorphous carbon matrix and form pure platinum deposits. Enhanced mobility of residual H2O molecules via a localized injection of inert Ar-H2 (4%) is attributed to be the reactive gas species for purification of the deposits. Surface purification of deposits was realized at laser exposure times as low as 0.1 s. The ex situ purification reaction in the deposit interior was shown to be rate-limited by reactive gas diffusion into the deposit, and deposit contraction associated with the purification process caused some loss of shape retention. To circumvent the intrinsic flaws of the ex situ anneal process, in situ deposition and purification techniques were explored that resemble a direct write atomic layer deposition (ALD) process. First, we explored a laser-assisted electron-beam-induced deposition (LAEBID) process augmented with reactive gas that resulted in a 75% carbon reduction compared to standard EBID. A sequential deposition plus purification process was also developed and resulted in deposition of pure platinum deposits with high fidelity and shape retention.

Electron-stimulated purification of platinum nanostructures grown via focused electron beam induced deposition.

Platinum-carbon nanostructures deposited via electron beam induced deposition from MeCpPt(IV)Me3 are purified during a post-deposition electron exposure treatment in a localized oxygen ambient at room temperature. Time-dependent studies demonstrate that the process occurs from the top-down. Electron beam energy and current studies demonstrate that the process is controlled by a confluence of the electron energy loss and oxygen concentration. Furthermore, the experimental results are modeled as a 2nd order reaction which is dependent on both the electron energy loss density and the oxygen concentration. In addition to purification, the post-deposition electron stimulated oxygen purification process enhances the resolution of the EBID process due to the isotropic carbon removal from the as-deposited materials which produces high-fidelity shape retention.

Purification of nanoscale electron-beam-induced platinum deposits via a pulsed laser-induced oxidation reaction.

Platinum-carbon deposits made via electron-beam-induced deposition were purified via a pulsed laser-induced oxidation reaction and erosion of the amorphous carbon to form pure platinum. Purification proceeds from the top down and is likely catalytically facilitated via the evolving platinum layer. Thermal simulations suggest a temperature threshold of ∼485 K, and the purification rate is a function of the PtC5 thickness (80-360 nm) and laser pulse width (1-100 µs) in the ranges studied. The thickness dependence is attributed to the ∼235 nm penetration depth of the PtC5 composite at the laser wavelength, and the pulse-width dependence is attributed to the increased temperatures achieved at longer pulse widths. Remarkably fast purification is realized at cumulative laser exposure times of less than 1 s.

Electron-beam-assisted oxygen purification at low temperatures for electron-beam-induced pt deposits: towards pure and high-fidelity nanostructures.

Nanoscale metal deposits written directly by electron-beam-induced deposition, or EBID, are typically contaminated because of the incomplete removal of the original organometallic precursor. This has greatly limited the applicability of EBID materials synthesis, constraining the otherwise powerful direct-write synthesis paradigm. We demonstrate a low-temperature purification method in which platinum-carbon nanostructures deposited from MeCpPtIVMe3 are purified by the presence of oxygen gas during a post-electron exposure treatment. Deposit thickness, oxygen pressure, and oxygen temperature studies suggest that the dominant mechanism is the electron-stimulated reaction of oxygen molecules adsorbed at the defective deposit surface. Notably, pure platinum deposits with low resistivity and retain the original deposit fidelity were accomplished at an oxygen temperature of only 50 °C.

Optimization of couch translational corrections to compensate for rotational and deformable target deviations in image guided radiotherapy.

The utilization of image-guided radiotherapy (IGRT) technologies helps correct temporal and spatial deviations of the target volume relative to planned radiation beams. With the aid of these IGRT technologies, it becomes possible to better identify the target volume before and even during radiation treatment. However, since components of the detected deviations may be translational, rotational, and deformable, the question remains whether simple treatment-couch translational movement can be optimized to compensate for these complicated deviations. Deviation of the target volume and changes in patient body shape from that acquired for treatment planning may further add to the variations from planned dose distribution. In this study, an optimization strategy is developed to investigate these issues. The optimization process involved the use of the hill climbing algorithm, the detected target volume and patient body shape, and the dose distribution based on acquired images at treatment. During the process, the planned dose distribution was iteratively adjusted to reflect the changes of depth and distance as the translational treatment couch movement was being optimized. The optimal treatment couch movement was considered achieved when the highest fraction of the detected target volume was covered by prescription dose. This optimization strategy was evaluated on clinical prostate cancer cases. For each of the cases, cone beam computed tomography (CBCT) images were acquired right after fiducial marker-based kilovolt orthogonal imaging verification and setup adjustment. Based on the CBCT images, the clinical target volume at the treatment was delineated and the translational treatment-couch movements were optimized with the developed strategy. The resultant dose coverage was compared to that without the optimization. The results showed that with the present strategy, rotational and deformable target deviations can be further compensated with translational couch correction.