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In October 2010, a United Nations peacekeeping mission to Haiti following a highly destructive earthquake inadvertently introduced cholera (1,2), leading to [approximately equal to] 820,000 cases and [approximately equal to] [...]

This study explored how early childhood intervention (ECI) professionals could support the development of secure attachment in children with developmental delay or disability (DD) within the context of ECI in Australia. Secure parent--child attachment is conducive to the aims of ECI to enhance the development, well-being, and participation of children with DD. Constructivist grounded theory methodology was applied to collect and analyze data from in-depth, semi-structured interviews with three parents and 18 professionals. Seven conceptual categories were selected: (a) Importance; (b) Challenges; (c) The System; (d) The Key Worker; (e) Assessment; (f) Strategies; and (g) Outcomes. Two dominant themes were identified: the quality of the relationship between the ECI professional and the family and self-regulation. An attachment-focused ECI framework is proposed, aligned with the ecological system model.

Abstract The eastern North American margin community seismic experiment (ENAM‐CSE) was conceived to target the ENAM Geodynamic Processes at Rifting and Subducting Margins (GeoPRISMS) primary site with a suite of both active‐ and passive‐source seismic data that would shed light on the processes associated with rift initiation and evolution. To fully understand the ENAM, it was necessary to acquire a seismic dataset that was both amphibious, spanning the passive margin from the continental interior onto the oceanic portion of the North American plate, and multiresolution, enabling imaging of the sediments, crust, and mantle lithosphere. The ENAM‐CSE datasets were collected on‐ and offshore of North Carolina and Virginia over a series of cruises and land‐based deployments between April 2014 and June 2015. The passive‐source component of the ENAM‐CSE included 30 broadband ocean‐bottom seismometers (OBSs) and 3 onshore broadband instruments. The broadband stations were deployed contemporaneously with those of the easternmost EarthScope Transportable Array creating a trans‐margin amphibious seismic dataset. The active‐source portion of the ENAM‐CSE included several components: (1) two onshore wide‐angle seismic profiles where explosive shots were recorded on closely spaced geophones; (2) four major offshore wide‐angle seismic profiles acquired with an airgun source and short‐period OBSs (SPOBSs), two of which were extended onland by deployments of short‐period seismometers; (3) marine multichannel seismic (MCS) data acquired along the four lines of SPOBSs and a series of other profiles along and across the margin. During the cruises, magnetic, gravity, and bathymetric data were also collected along all MCS profiles. All of the ENAM‐CSE products were made publicly available shortly after acquisition, ensuring unfettered community access to this unique dataset.

Seismic tomography observations show a low‐velocity feature in the upper mantle beneath eastern North America known as the Northern Appalachian Anomaly (NAA). Proposed models for the formation of the NAA include a remnant high‐temperature feature resulting from the passage of the Great Meteor Hotspot, edge‐driven convection, and ongoing asthenospheric upwelling. We investigate the structure of the lithosphere above the central portion of the NAA using data from the New England Seismic Transects (NEST) experiment. Ps receiver functions reveal two consistent interfaces beneath the dense northern line of NEST: the Moho (the base of the crust) and a deeper negative velocity gradient (NVG) feature located at depths between 60 and 110 km. We consider several potential explanations for this NVG feature; based on comparisons with previous results, we propose that it likely corresponds to the lithosphere‐asthenosphere boundary. Our results indicate that the lithosphere beneath New England is nonuniform and has likely been thinned. Plain Language Summary: Eastern North America has a rich geologic history. One puzzling aspect of the seismic structure of New England is that it overlies a prominent region of anomalously low seismic velocities in the upper mantle, known as the Northern Appalachian Anomaly (NAA). The origin of this feature remains poorly understood; furthermore, it is not clear whether and how the upper mantle anomaly has affected the tectonic plate above it. Here we use data from seismic stations of the New England Seismic Transects (NEST) array to study the thickness of the continental lithosphere above the NAA. Specifically, we examine P waves from distant earthquakes and look for evidence of P wave to S wave conversions at the base of the lithosphere. We find evidence for particularly thin lithosphere, indicating that it has been thinned over geologic time. Key Points: We use P‐to‐S receiver function analysis to identify negative velocity gradients beneath New EnglandWe find evidence for prominent negative velocity gradients between ∼60 and 110 km depth across stations of the NEST arrayWe infer relatively thin continental lithosphere above the Northern Appalachian Anomaly (NAA) in the upper mantle [ABSTRACT FROM AUTHOR]

Observations of seismic waves that have passed through the Earth's lowermost mantle provide insight into deep mantle structure and dynamics, often on relatively small spatial scales. Here we use SKS, S2KS, S3KS, and PKS signals recorded across a large region including the United States, Mexico, and Central America to study the deepest mantle beneath large swaths of North America and the northeastern Pacific Ocean. These phases are enhanced via beamforming and then used to investigate polarization‐ and propagation direction‐dependent shear wave speeds (seismic anisotropy). A differential splitting approach enables us to robustly identify contributions from D″ ${\mathrm{D}}^{{\prime\prime}}$ anisotropy. Our results show strong seismic anisotropy in approximately half of our study region, indicating that D″ ${\mathrm{D}}^{{\prime\prime}}$ anisotropy may be more prevalent than commonly thought. In some regions, the anisotropy may be induced by flow driven by sinking cold slabs, and in other, more compact regions, by upwelling flow. Measured splitting due to lowermost mantle anisotropy is sufficiently strong to be non‐negligible in interpretations of SKS splitting due to upper mantle anisotropy in certain regions, which may prompt future re‐evaluations of upper mantle anisotropy beneath North and Central America. Plain Language Summary: Earthquakes emit seismic waves that travel through Earth's deep interior. In some parts of Earth, the speed of these waves depends on their vibrational directions. In these cases, the material they travel through can be described as seismically anisotropic. Such seismic anisotropy is often caused by material deformation due to convective flow in Earth's interior. We show in this work that Earth's mantle beneath North America and the northeastern Pacific Ocean is seismically anisotropic in many places just above its boundary with the core at a depth of ∼2900km ${\sim} 2900\,\text{km}$. In some of these places, the deformation may be caused by sinking subducted slabs, upwelling flow, or changes in horizontal flow at the mantle's lower boundary layer. We additionally show that potential contributions from the lowermost mantle anisotropy cannot always be neglected when measuring seismic anisotropy in other parts of the mantle. Key Points: We infer D″ ${\mathrm{D}}^{{\prime\prime}}$ seismic anisotropy beneath North America and parts of the Pacific Ocean from beamformed SKS, S2KS, S3KS, and PKS dataWe find widespread seismic anisotropy in the deepest mantle, likely induced by a variety of different convective flow regimesThe influence of the deepest mantle on SKS (usually used to infer upper mantle anisotropy) is non‐negligible in some regions [ABSTRACT FROM AUTHOR]

Previous geophysical studies in the New England Appalachians identified a ∼15 km offset in crustal thickness near the surface boundary between Laurentia and the accreted terranes. Here, we investigate crustal structure using data from a denser array: New England Seismic Transects experiment, which deployed stations spaced ∼10 km apart across the Laurentia‐Moretown terrane suture in northwestern Massachusetts. We used receiver function (RF) analysis to detect P to SV converted waves and identified multiple interfaces beneath the transect. We also implemented a harmonic decomposition analysis to identify features at or near the Moho with dipping and/or anisotropic character. Beneath the Laurentian margin, the Ps converted phase from the Moho arrives almost 5.5 s after the initial P wave, whereas beneath the Appalachian terranes, the pulse arrives at 3.5 s, corresponding to ∼48 and ∼31 km depth, respectively. The character of the RF traces beneath stations in the middle of our array suggests a complex transitional zone with dipping and/or anisotropic boundaries extending at least ∼30 km. This extension is measured in our profiles and perpendicular to the suture. We propose one possible crustal geometry model that is consistent with our observations and results from previous studies. Plain Language Summary: We explore the crustal structure that developed during the formation of the Appalachian Mountains beneath northwestern Massachusetts during the Paleozoic. In this region, the geology reflects the accretion of multiple terranes onto Laurentia, the ancient core of North America. Previous studies using seismic data have shown evidence for crustal geometries beneath New England that reflect a complex tectonic history of the formation of the Appalachians. We processed recordings of waves from distant earthquakes measured at seismic stations including the New England Seismic Transects array, which has seismic observatories spaced about 10 km apart. This approach allows a clear visualization of the deep crustal geometry beneath the area. We found evidence for a sharp contrast in crustal thickness near the boundary between Laurentia and the Moretown terrane, which was the first terrane accreted. Near the boundary between these terranes, we found evidence for a complex and overlapping set of crust‐mantle interfaces. We also identified a highly deformed crust with a layer that shows strong seismic anisotropy (the directional dependence of seismic wave speeds). We created a model for the evolution of crustal structure based on the interpretation of our seismic results along with previous studies based on thermochronologic, paleogeographic, and geophysical data. Key Points: Dense seismic array provides detailed resolution of the crustal thickness and Moho geometry beneath the Appalachians of NW MassachusettsCrustal thickness beneath Laurentia (∼44 km) and accreted terranes (∼32 km) is very different with a complex transition zone and a possible step‐like Moho geometryAn anisotropic layer near the zone of Moho complexity indicates a highly deformed zone near the base of the crust [ABSTRACT FROM AUTHOR]

Background: To explore media awareness efforts regarding family violence during the COVID-19 pandemic in Saudi Arabia and compare them to global standards. Methods: This scoping review included media awareness efforts: interviews, lectures, workshops, and forums. Moreover, all efforts must be regarding positive parenting, family well-being, care of the elderly, domestic violence, child abuse, and neglect during the first nine months of the COVID-19 pandemic (April-December 2020). Results: Seven organizations in Saudi Arabia initiated 32 awareness programs; the National Family Safety Program implemented 17(53%) of awareness efforts, followed by the Family Affairs Council 6(19%). The qualitative analysis of the awareness transcripts utilized three main themes: promoting family well-being, supporting the victims, and preventing family violence. Conclusion: Considering global efforts in Australia, Greenland, France, Spain, and Italy. Like other countries, Saudi Arabia could use more advanced measures to prevent and respond appropriately to family violence during pandemic-like situations. [ABSTRACT FROM AUTHOR]

Convective flow in the deep mantle controls Earth's dynamic evolution, influences plate tectonics, and has shaped Earth's current surface features. Present and past convection‐induced deformation manifests itself in seismic anisotropy, which is particularly strong in the mantle's uppermost and lowermost portions. While the general patterns of seismic anisotropy have been mapped for the upper mantle, anisotropy in the lowermost mantle (called D′′) is at an earlier stage of exploration. Here we review recent progress in methods to measure and interpret D′′ anisotropy. Our understanding of the limitations of existing methods and the development of new measurement strategies have been aided enormously by the availability of high‐performance computing resources. We give an overview of how measurements of seismic anisotropy can help constrain the mineralogy and fabric of the deep mantle. Specifically, new and creative strategies that combine multiple types of observations provide much tighter constraints on the geometry of anisotropy than have previously been possible. We also discuss how deep mantle seismic anisotropy provides insights into lowermost mantle dynamics. We summarize what we have learned so far from measurements of D′′ anisotropy, how inferences of lowermost mantle flow from measurements of seismic anisotropy relate to geodynamic models of mantle flow, and what challenges we face going forward. Finally, we discuss some of the important unsolved problems related to the dynamics of the lowermost mantle that can be elucidated in the future by combining observations of seismic anisotropy with geodynamic predictions of lowermost mantle flow. Plain Language Summary: Earthquakes cause waves that travel through Earth's interior and are recorded by distant seismometers. These seismic waves behave differently depending on the material that they pass through, revealing Earth's material properties. At the very bottom of the mantle, seismic waves sometimes travel at different speeds depending on their direction. This material property is called seismic anisotropy and is caused by material deformation and flow. Global patterns of mantle flow, which is directly connected to surface processes such as the movement of tectonic plates or hotspot volcanism, can therefore be inferred from seismic anisotropy. Recent years have seen advances in anisotropy imaging in the lowermost mantle as well as in numerical calculations of flow in Earth's lowermost mantle. We review the methods that are used to infer lowermost mantle anisotropy. We further give an overview of previous results and interpretations, which include seismic anisotropy caused by upwelling plumes and ancient slab remnants. Future improvements in the fields of seismology, geodynamics, and mineral physics are needed to improve our understanding of global deep mantle flow. Key Points: Measurement techniques for deep mantle anisotropy have been improved substantially in the last decadeThese improvements enable inferences of deep mantle flow with increasing confidenceKnowledge of mantle dynamics elucidates the drivers of flow, relationships among structures, and Earth's dynamic evolution [ABSTRACT FROM AUTHOR]

Continental lithosphere is deformed, destroyed, or otherwise modified in several ways. Processes that modify the lithosphere include subduction, terrane accretion, orogenesis, rifting, volcanism/magmatism, lithospheric loss or delamination, small-scale or edge-driven convection, and plume-lithosphere interaction. The eastern North American margin (ENAM) provides an exceptional locale to study this broad suite of processes, having undergone multiple complete Wilson cycles of supercontinent formation and dispersal, along with ∼200 Ma of postrift evolution. Moreover, recent data collection efforts associated with EarthScope, GeoPRISMS, and related projects have led to a wealth of new observations in eastern North America. Here I highlight recent advances in our understanding of the structure of the continental lithosphere beneath eastern North America and the processes that have modified it through geologic time, with a focus on recent geophysical imaging that has illuminated the lithosphere in unprecedented detail. Eastern North America experienced a range of processes that deform, destroy, or modify continental lithosphere, providing new insights into how lithosphere evolves through time. Subduction and terrane accretion, continental rifting, and postrift evolution have all played a role in shaping lithospheric structure beneath eastern North America. Relict structures from past tectonic events are well-preserved in ENAM lithosphere; however, lithospheric modification that postdates the breakup of Pangea has also been significant. [ABSTRACT FROM AUTHOR]

We investigated the interaction between the insect-specific virus, Piura virus (PIUV), and the arbovirus Zika virus (ZIKV) in Aedes albopictus cells. We performed coinfection experiments in C6/36 cells. Piura virus (Cor 33 strain, Colombia) and ZIKV (PRVABC58 strain, Puerto Rico) were co-inoculated into C6/36 cells using two multiplicity of infection (MOI) combinations: 0.1 for both viruses and 1.0 for ZIKV, 0.1 for PIUV. Wells were infected in triplicate with either PIUV and ZIKV coinfection, ZIKV-only, or PIUV-only. Mock infected cells served as control wells. The cell suspension was collected daily 7 days post-infection. Zika virus load was titrated by TCID50 on Vero 76 cells. The ZIKV-only infection and PIUV and ZIKV coinfection experiments were also quantified by RT-qPCR. We also investigated whether ZIKV interfered in the PIUV replication. PIUV suppressed the replication of ZIKV, resulting in a 10,000-fold reduction in ZIKV titers within 3 days post-infection. PIUV viral loads were not reduced in the presence of ZIKV. We conclude that, when concurrently infected, PIUV suppresses ZIKV in C6/36 cells while ZIKV does not interfere in PIUV replication. [ABSTRACT FROM AUTHOR]

We present a simple, ultra-rapid and robust method to create sharp nanostructures-nanopetals-in a shape memory polymer substrate demonstrating unprecedented enhancements for surface enhanced sensing over large surface areas. These bimetallic nanostructures demonstrate extremely strong surface plasmon resonance effects due to the high density multifaceted petal structures that increase the probability of forming nanogaps. We demonstrate that our nanopetals exhibit extremely strong surface plasmons, confining the emission and enhancing the fluorescence intensity of the nearby high-quantum yield fluorescein by >4000×. The enhancements are confined to the extremely small volumes at the nanopetal borders. This enables us to achieve single molecule detection at relatively high and physiological concentrations. © 2010 American Institute of Physics.

We present a theory for the multiple scattering of light by obstacles situated over a rough surface. This problem is important for applications in biological and chemical sensors. To keep the formulation of this theory simple, we study scalar waves. This theory requires knowledge of the scattering operator (t-matrix) for each of the obstacles as well as the reflection operator for the rough surface. The scattering operator gives the field scattered by the obstacle due to an exciting field incident on the scatterer. The reflection operator gives the field reflected by the rough surface due to an exciting field incident on the rough surface. We apply this general theory for the special case of point scatterers and a slightly rough surface with homogeneous Dirichlet and Neumann boundary conditions. We show examples that demonstrate the utility of this theory.

(Figure Presented) Controllable biaxial and uniaxial nanowrinkles (see figure) are fabricated by a simple two-step approach - metal deposition and subsequent heating - based on shape memory polymer (prestressed polystyrene) sheets. The wavelengths of the wrinkles can be tuned by controlling the thickness of deposited metal. The ready integration of the nanowrinkles into microchannels and their effectiveness in surface enhanced sensing is demonstrated. © 2009 Wiley-VCH Verlag GmbH & Co. KGaA.

Along‐strike variation of the Laurentian rifted margin and the Appalachian orogen has long been recognized in the geologic record. We investigated the manifestation of this along‐strike variation at depth by generating scattered wavefield migration profiles from four dense seismic arrays deployed across the Appalachian orogen at different latitudes. All profiles exhibit a similar crustal thickness decrease of 15–20 km from the Mesoproterozoic Grenville Province to the Paleozoic Appalachian accreted terranes, but the Moho architecture differs dramatically along strike. The profiles beneath the central and southern Appalachians show a smoothly varying Moho geometry; in contrast, there is an abrupt Moho depth offset beneath the New England Appalachians. This contrast in Moho geometry may result from variations in the Laurentian rifted margin architecture, changes in Taconic orogeny subduction polarity, and greater crustal shortening during the Acadian‐Neoacadian orogeny in southern New England and the Alleghanian orogeny in the central and southern Appalachians. A first‐order along‐strike transition in the behavior of Appalachian orogenic processes is located between the central and New England Appalachians. Plain Language Summary: The Proterozoic Grenville Province and Paleozoic Appalachian domains are the two major tectonic units in eastern North America, associated with two past supercontinent cycles. The Grenville Province has generally thicker crust than the Appalachian domains, and a Moho depth decrease from Grenville to Appalachians has been observed throughout the Appalachian orogen by previous continental‐scale seismic studies. The Moho beneath the Laurentian margin records how the Proterozoic rifted margin of Laurentia interacted with the Paleozoic Appalachian orogenesis at crustal levels. However, the detailed geometry of the Moho beneath the edge of Laurentia, and how it varies along the margin, have not been resolved by previous work. In this study, we apply a scattered wavefield migration imaging technique to four dense seismic arrays deployed at different latitudes across the Appalachian orogen to investigate the geometry of the Moho across the Grenville‐Appalachian transition. The Moho depth change is smooth beneath the central and southern Appalachians but abrupt beneath New England. This distinction may result from a combination of a non‐uniform Grenville rifted margin, different styles and directions of Appalachian subduction and terrane accretion episodes, and varied amount of crustal shortening along the Appalachian orogen. Key Points: We investigated the Moho geometry beneath the Grenville‐Appalachian transition using the scattered wavefield migration techniqueThe Moho depth change is gradual beneath the central and southern Appalachians, but abrupt beneath New EnglandVaried Moho geometries provide new insights into along‐strike variations in tectonic settings before and during Appalachian orogenesis [ABSTRACT FROM AUTHOR]