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Understanding the response of coastal barriers to future changes in rates of sea level rise, sediment availability, and storm intensity/frequency is essential for coastal planning, including socioeconomic and ecological management. Identifying drivers of past changes in barrier morphology, as well as barrier sensitivity to these forces, is necessary to accomplish this. Using remote sensing, field, and laboratory analyses, we reconstruct the mesoscale (decades–centuries) evolution of central Fire Island, a portion of a 50 km barrier island fronting Long Island, New York, USA. We find that the configuration of the modern beach and foredune at Fire Island is radically different from the system's relict morphostratigraphy. Central Fire Island is comprised of at least three formerly inlet-divided rotational barriers with distinct subaerial beach and dune–ridge systems that were active prior to the mid-19th century. Varying morphologic states reflected in the relict barriers (e.g., progradational and transgressive) contrast with the modern barrier, which is dominated by a tall and nearly continuous foredune and is relatively static, except for erosion and drowning of its fringing marsh. We suggest that this state shift indicates a transition from a regime dominated by inlet-mediated gradients in alongshore sediment availability to one where human impacts exerted greater influence on island evolution from the late 19th century onward. The retention of some geomorphic capital in Fire Island's relict subaerial features combined with its static nature renders the barrier increasingly susceptible to narrowing and passive submergence. This may lead to an abrupt geomorphic state shift in the future, a veiled vulnerability that may also exist in other stabilized barriers.

Abstract The effects of microgravity on soft matter morphogenesis have been documented in countless experiments, but physical understanding is still lacking in many cases. Here we review how gravity affects shape emergence and pattern formation for both inert matter and living systems of different biological complexities. We highlight the importance of building physical models for understanding the experimental results available. Answering these fundamental questions will not only solve basic scientific problems, but will also enable several industrial applications relevant to space exploration.

Barrier islands and their associated backbarrier environments protect mainland population centers and infrastructure from storm impacts, support biodiversity, and provide long-term carbon storage, among other ecosystem services. Despite their socio-economic and ecological importance, the response of coupled barrier-marsh-lagoon environments to sea-level rise is poorly understood. Undeveloped barrier-marsh-lagoon systems typically respond to sea-level rise through the process of landward migration, driven by storm overwash and landward mainland marsh expansion. Such response, however, can be affected by human development and engineering activities such as lagoon dredging and shoreline stabilization. To better understand the difference in the response between developed and undeveloped barrier-marsh-lagoon environments to sea-level rise, we perform a local morphologic analysis that describes the evolution of Long Beach Island (LBI), New Jersey, over the last 182 years. We find that between 1840 and 1934 the LBI system experienced landward migration of all five boundaries, including 171 meters of shoreline retreat. Between the 1920s and 1950s, however, there was a significant shift in system behavior that coincided with the onset of groin construction, which was enhanced by beach nourishment and lagoon dredging practices. From 1934 to 2022 the LBI system experienced ~22 meters of shoreline progradation and a rapid decline in marsh platform extent. Additionally, we extend a morphodynamic model to describe the evolution of the system in terms of five geomorphic boundaries: the ocean shoreline and backbarrier-marsh interface, the seaward and landward lagoon-marsh boundaries, and the landward limit of the inland marsh. We couple this numerical modeling effort with the map analysis during the undeveloped phase of LBI evolution, between 1840 and 1934. Despite its simplicity, the modeling framework can describe the average cross-shore evolution of the barrier-marsh-lagoon system during this period without accounting for human landscape modifications, supporting the premise that natural processes were the key drivers of morphological change. Overall, these results suggest that anthropogenic effects have played a major role in the evolution of LBI over the past century by altering overwash fluxes and marsh-lagoon geometry; this is likely the case for other barrier-marsh-lagoon environments around the world.

Luca Al Sabbagh, Daniele Santarelli, Herman H. Schwedt e Domizia Weber. Giudici della Fede. L'Inquisizione romana e i suoi tribunali in eta moderna. Firenze: Edizioni Clori, 2017. Daniele Santarelli e [...]

Initially, stressed plates are widely used in modern fabrication techniques, such as additive manufacturing and UV lithography, for their tunable morphology by application of external stimuli. In this work, we propose a formal asymptotic derivation of the Föppl–von Kármán equations for an elastic plate with initial stresses, using the constitutive theory of nonlinear elastic solids with initial stresses under the assumptions of incompressibility and material isotropy. Compared to existing works, our approach allows us to determine the morphological transitions of the elastic plate without prescribing the underlying target metric of the unstressed state of the elastic body. We explicitly solve the derived FvK equations in some physical problems of engineering interest, discussing how the initial stress distribution drives the emergence of spontaneous curvatures within the deformed plate. The proposed mathematical framework can be used to tailor shape on demand, with applications in several engineering fields ranging from soft robotics to four-dimensional printing.

Barrier coasts, including barrier islands, beach-ridge plains, and associated landforms, can assume a broad spectrum of morphologies over multi-decadal scales that reflect conditions of sediment availability, accommodation, and relative sea-level rise. However, the quantitative thresholds of these controls on barrier-system behavior remain largely unexplored, even as modern sea-level rise and anthropogenic modification of sediment availability increasingly reshape the world's sandy coastlines. In this study, we conceptualize barrier coasts as sediment-partitioning frameworks, distributing sand delivered from the shoreface to the subaqueous and subaerial components of the coastal system. Using an idealized morphodynamic model, we explore thresholds of behavioral and morphologic change over decadal to centennial timescales, simulating barrier evolution within quasi-stratigraphic morphological cross sections. Our results indicate a wide diversity of barrier behaviors can be explained by the balance of fluxes delivered to the beach vs. the dune or backbarrier, including previously understudied forms of transgression that allow the subaerial system to continue accumulating sediment during landward migration. Most importantly, our results show that barrier state transitions between progradation, cross-shore amalgamation, aggradation, and transgression are controlled largely through balances within a narrow range of relative sea-level rise and sediment flux. This suggests that, in the face of rising sea levels, subtle changes in sediment fluxes could result in significant changes in barrier morphology. We also demonstrate that modeled barriers with reduced vertical sediment accommodation are highly sensitive to the magnitude and direction of shoreface fluxes. Therefore, natural barriers with limited sediment accommodation could allow for exploration of the future effects of sea-level rise and changing flux magnitudes over a period of years as opposed to the decades required for similar responses in sediment-rich barrier systems. Finally, because our model creates stratigraphy generated under different input parameters, we propose that it could be used in combination with stratigraphic data to hindcast the sensitivity of existing barriers and infer changes in prehistoric morphology, which we anticipate will provide a baseline to assess the reliability of forward modeling predictions.

Professional advocacy in the field of school counseling is critical to promote the profession and ensure that school counselors are engaged in appropriate roles that are aligned with the American School Counselor Association (ASCA). To better understand how they are engaging in this important work, we interviewed and surveyed school counselors about their experiences with professional advocacy. Findings suggest that school counselors possess strengths and face challenges when advocating for their roles.

The present paper is dedicated to the structural stability of the linear model of a mixture of two porous solids. It is shown that the variation of the characteristic coefficients that describe the coupling of the various mechanical effects involved in the model in concern does not destroy its structure. This means that any small variation of these coefficients leads to small variations in the corresponding solutions of the associated initial boundary value problems. For this purpose, more mathematical estimates are presented describing precisely the continuous dependence of the solutions with respect to all external given data of the initial boundary value problem, as well as with respect to appropriate measures of the set of coupling parameters. This allows the conclusion that the model of the mixture of porous materials is consistent. In particular, it is believed that the estimates obtained in terms of structural stability are particularly meaningful with regard to the materials used in building contexts and the related decay phenomena. [ABSTRACT FROM AUTHOR]

Understanding the response of coastal barriers to future changes in rates of sea level rise, sediment availability, and storm intensity/frequency is essential for coastal planning, including socioeconomic and ecological management. Identifying drivers of past changes in barrier morphology, as well as barrier sensitivity to these forces, is necessary to accomplish this. Using remote sensing, field, and laboratory analyses, we reconstruct the mesoscale (decades–centuries) evolution of central Fire Island, a portion of a 50 km barrier island fronting Long Island, New York, USA. We find that the configuration of the modern beach and foredune at Fire Island is radically different from the system's relict morphostratigraphy. Central Fire Island is comprised of at least three formerly inlet-divided rotational barriers with distinct subaerial beach and dune–ridge systems that were active prior to the mid-19th century. Varying morphologic states reflected in the relict barriers (e.g., progradational and transgressive) contrast with the modern barrier, which is dominated by a tall and nearly continuous foredune and is relatively static, except for erosion and drowning of its fringing marsh. We suggest that this state shift indicates a transition from a regime dominated by inlet-mediated gradients in alongshore sediment availability to one where human impacts exerted greater influence on island evolution from the late 19th century onward. The retention of some geomorphic capital in Fire Island's relict subaerial features combined with its static nature renders the barrier increasingly susceptible to narrowing and passive submergence. This may lead to an abrupt geomorphic state shift in the future, a veiled vulnerability that may also exist in other stabilized barriers. [ABSTRACT FROM AUTHOR]

The National Highway Traffic Safety Administration issued guidelines on the safe transport of pediatric patients to lessen the chance of injury during ambulance transport. However, adherence to these standards have been slow to take hold. The objective of this quality improvement study is to evaluate barriers and facilitators of safe transport at the individual, organizational, and societal levels and identify improvement opportunities in the safe transport of pediatric patients. This study was designed using an implementation science framework. Six focus groups were held with EMS clinicians to assess knowledge, behaviors, barriers, and facilitators of safe pediatric transport. Four interviews were conducted with EMS leadership to characterize organizational safe transport practices and policies. Detailed notes were taken during focus groups; interviews were recorded and transcribed. Qualitative data were analyzed using a thematic content analysis approach where team members reviewed transcripts using an established framework and identified major and minor themes related to safe pediatric transport. Three focus groups were conducted in a hospital setting and three were conducted at EMS base stations. Interview participants included two paramedic leaders, an ambulance service chief executive officer, and an ambulance service clinical coordinator. Recurring themes included the belief that children were inherently difficult to transport, the sentiment that training in pediatric transport is lacking, and the acknowledgement that familiarity with pediatric transport guidelines is low. Additionally, a major theme was that situational practicality can take precedence over adherence to best practice recommendations. Participants reported the presence of organizational and external barriers that made it more difficult for EMS personnel to follow safety guidelines. This included equipment unavailability, lack of clear policies, low pediatric patient volume, manufacturer design preferences, and prevailing EMS culture/norms. EMS clinicians need hands-on training and knowledge reinforcement in safe pediatric ground ambulance transport. EMS agencies should ensure that their crews have proper equipment, training, and protocols in place. Regulators and manufacturers can be catalysts for the implementation of these recommendations. Substantial change at the individual, organizational, and societal levels are needed to improve the safety of pediatric patients being transported via ground ambulance. [ABSTRACT FROM AUTHOR]

This work investigates the mechano-biological features of cells cultured in monolayers in response to different osmotic conditions. In-vitro experiments have been performed to quantify the long-term effects of prolonged osmotic stresses on the morphology and proliferation capacity of glioblastoma cells. The experimental results highlight that both hypotonic and hypertonic conditions affect the proliferative rate of glioblastoma cells on different cell cycle phases. Moreover, glioblastoma cells in hypertonic conditions display a flattened and elongated shape. The latter effect is explained using a nonlinear elastic model for the single cell. Due to a crossover between the free energy contributions related to the cytosol and the cytoskeletal fibers, a critical osmotic stress determines a morphological transition from a uniformly compressed to an elongated shape.

Background People living with HIV/AIDS (PLWHA) must contend with a significant burden of disease. However, current studies of this demographic have yielded wide variations in the incidence of suicidality (defined as suicidal ideation, suicide attempt and suicide deaths).Aims This systematic review and meta-analysis aimed to assess the lifetime incidence and prevalence of suicidality in PLWHA.Methods Publications were identified from PubMed (MEDLINE), SCOPUS, OVID (MEDLINE), Joanna Briggs Institute EBP and Cochrane Library databases (from inception to before 1 February 2020). The search strategy included a combination of Medical Subject Headings associated with suicide and HIV. Researchers independently screened records, extracted outcome measures and assessed study quality. Data were pooled using a random-effects model. Subgroup and meta-regression analyses were conducted to explore the associated risk factors and to identify the sources of heterogeneity. Main outcomes were lifetime incidence of suicide completion and lifetime incidence and prevalence of suicidal ideation and suicide attempt.Results A total of 185 199 PLWHA were identified from 40 studies (12 cohorts, 27 cross-sectional and 1 nested case-control). The overall incidence of suicide completion in PLWHA was 10.2/1000 persons (95%CI: 4.5 to 23.1), translating to 100-fold higher suicide deaths than the global general population rate of 0.11/1000 persons. The lifetime prevalence of suicide attempts was 158.3/1000 persons (95%CI: 106.9 to 228.2) and of suicidal ideation was 228.3/1000 persons (95%CI: 150.8 to 330.1). Meta-regression revealed that for every 10-percentage point increase in the proportion of people living with HIV with advanced disease (AIDS), the risk of suicide completion increased by 34 per 1000 persons. The quality of evidence by Grading of Recommendations, Assessment, Development and Evaluations for the suicide deaths was graded as ‘moderate’ quality.Conclusions The risk of suicide death is 100-fold higher in people living with HIV than in the general population. Lifetime incidence of suicidal ideation and attempts are substantially high. Suicide risk assessments should be a priority in PLWHA, especially for those with more advanced disease.

AIM:To estimate the pooled prevalence and incidence of suicidal ideation, attempts, and deaths in people with sleep apnea. METHOD:We will identify epidemiological studies reporting the prevalence or incidence rate of suicide in people with sleep apnea. We will search the following databases: PubMed (MEDLINE), Scopus, Cochrane Library, OVID (HEALTH STAR), OVID (MEDLINE) and Joana Briggs Institute EBF Database. No age, geographical location, study-design or language limits will be applied. This protocol was developed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols (PRISMA-P) guidelines. Two reviewers (YY and YP) will independently screen citations, abstracts and will identify full-text articles for inclusion, extract data, and appraise the quality and bias of included studies. Discrepancies will be resolved by consulting with a third researcher (MC). Study quality will be assessed by the Newcastle-Ottawa Scale. The primary outcomes will be the overall prevalence or incidence of suicidal ideation, attempts and completion and the risk of suicide in people with sleep apnea. For pooling of the studies, we will use a random-effects model with a logit transformation. The DerSimonian and Laird (DL) random-effects method will be used to estimate the pooled inter-study variance. We will assess the between-study heterogeneity using I2 statistics, and Cochrane's Q statistic (significance level < 0.05). If the I2 is high (>75%), we will perform subgroup meta-analyses and conduct a meta-regression analysis to explore sources of study heterogeneity using study level median age, study-level proportions of race, gender, depression and quality scores. We will report effect estimates as suicide risk per 1000 individuals. Egger's test and funnel plots will be used to assess publication bias, and adjusted estimates using trim and fill methods will be reported if publication bias is suspected. ETHICS AND DISSEMINATION:No ethics clearance is required as no primary data will be collected. The results of this systematic review and meta-analysis will be presented at scientific conferences and published in a peer-review journal. The results may shed more light on the burden of suicide risk among individuals with sleep apnea and may guide future population-specific interventions. TRIAL REGISTRATION:PROSPERO registration number: CRD42020165404.

Our understanding of material instabilities in soft solids remains elusive mainly due to the mathematical challenges in capturing localised phenomena within nonlinear elastic materials. Ciarletta develops an analytical theory to describe the nucleation threshold of creases in agreement with experiments.

Submerged barrier deposits preserved on continental shelf seabeds provide a record of paleocoastal environmental change from the last glacial maximum through the Holocene. The formation of these offshore deposits is often attributed to intermittent periods of rapidly rising sea levels, especially glacial meltwater pulses, which are expected to lead to partial or complete drowning – overstepping – of migrating barrier islands. However, recent cross-shore modeling and field evidence suggests that even for constant sea-level rise and shelf slope, the internal dynamics of migrating barriers could plausibly drive periodic retreat accompanied by autogenic partial overstepping and deposition of barrier sediment. We hypothesize that the interaction of periodic retreat with changes in external (allogenic) forcing from sea-level rise may create novel retreat responses and corresponding relict barrier deposits. Specifically, we posit that autogenic deposits can be amplified by an increased rate of relative sea-level rise, while in other cases internal dynamics can disrupt or mask the production of allogenic deposits. Here, we model barriers through a range of autogenic–allogenic interactions, exploring how barriers with different inherent autogenic periods respond to discrete, centennial-scale sea-level-rise pulses of variable magnitude and timing within the autogenic transgressive barrier cycle. Our results demonstrate a diversity of depositional signals, where production of relict sands is amplified or suppressed depending on both the barrier’s internal dynamic state and the pulse magnitude. We also show that millennial-scale autogenic periodicity renders barriers vulnerable to complete drowning for relatively low pulse rates of rise (