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Coastal dunes, in particular foredunes, support a resilient ecosystem and reduce coastal vulnerability to storms. In contrast to dry desert dunes, coastal dunes arise from interactions between biological and physical processes. Ecologists have traditionally addressed coastal ecosystems by assuming that they adapt to preexisting dune topography, whereas geomorphologists have studied the properties of foredunes primarily in connection to physical, not biological, factors. Here, we study foredune development using an ecomorphodynamic model that resolves the coevolution of topography and vegetation in response to both physical and ecological factors. We find that foredune growth is eventually limited by a negative feedback between wind flow and topography. As a consequence, steady-state foredunes are scale invariant, which allows us to derive scaling relations for maximum foredune height and formation time. These relations suggest that plant zonation (in particular for strand “dune-building” species) is the primary factor controlling the maximum size of foredunes and therefore the amount of sand stored in a coastal dune system. We also find that aeolian sand supply to the dunes determines the timescale of foredune formation. These results offer a potential explanation for the empirical relation between beach type and foredune size, in which large (small) foredunes are found on dissipative (reflective) beaches. Higher waves associated with dissipative beaches increase the disturbance of strand species, which shifts foredune formation landward and thus leads to larger foredunes. In this scenario, plants play a much more active role in modifying their habitat and altering coastal vulnerability than previously thought.

Noncompressible truncal hemorrhage is a leading cause of potentially preventable death in trauma and acute care surgery patients. These patients are at high risk of exsanguination before potentially life-saving surgical intervention may be performed. Temporary aortic occlusion is an effective means of augmenting systolic blood pressure and perfusion of the heart and brain in these patients. Aortic occlusion temporarily controls distal bleeding until permanent hemostasis can be achieved. The traditional method for temporary aortic occlusion is via resuscitative thoracotomy with cross clamping of the descending aorta. While effective, resuscitative thoracotomy is highly invasive and may worsen blood loss, hypothermia, and coagulopathy by opening an otherwise uninjured body cavity. Resuscitative endovascular balloon occlusion of the aorta (REBOA) achieves temporary aortic occlusion using an occlusive balloon catheter that is introduced into the aorta via endovascular access of the common femoral artery. For this reason it is thought that REBOA could provide a less-invasive method for temporary aortic occlusion. Our purpose is to describe our experience with the implementation of REBOA at our Level 1 trauma center. A retrospective case series describing all cases of REBOA performed at a prominent level 1 trauma center between October 2011 and September 2015. The study inclusion criteria were any patient that received a REBOA procedure in the acute phases after injury. There were no exclusion criteria. Data were collected from electronic medical records and the hospital's trauma registry. A total of 31 patients underwent REBOA during the study period. The median age of REBOA patients was 47 (interquartile range [IQR] = 27 to 63) and 77% were male. A majority (87%) of patients sustained blunt trauma. The median injury severity score was 34 (IQR = 22 to 42). The overall survival rate was 32% but varied greatly between subgroups. Balloon inflation resulted in a median increase in systolic blood pressure of 55-mm Hg (IQR 33 to 60), in cases where the data were available (n = 20). A return to spontaneous circulation was noted in 60% of patients who had arrested before REBOA (n = 10). Overall, early death by hemorrhage was 28% with only 2 deaths in the emergency department before reaching the operating room. REBOA is an effective method for achieving temporary aortic occlusion in trauma patients with noncompressible truncal hemorrhage. Balloon inflation correlated with increased blood pressure and temporary hemorrhage control in a vast majority of patients.

Pancreatic ductal adenocarcinoma (PDA) is the fourth-leading cause of cancer death in the United States with a 5-year overall survival rate of 8% for all stages combined. But this decreases to 3% for the majority of patients that present with stage IV PDA at time of diagnosis. The lack of distinct early symptoms for PDA is one of the primary reasons for the late diagnosis. Common symptoms like weight loss, abdominal and back pains, and jaundice are often mistaken for symptoms of other issues and do not appear until the cancer has progressed to a late stage. Thus the development of novel imaging platforms for PDA is crucial for the early detection of the disease. MUC1 is a tumor-associated antigen (tMUC1) expressed on 80% of PDA. The goal of this study was to determine the targeting and detection capabilities of a tMUC1 specific antibody, TAB004. TAB004 antibody conjugated to a near infrared fluorescent probe was injected intraperitoneally into immune competent orthotopic and spontaneous models of PDA. Results show that fluorophore conjugated TAB004 specifically targets a) 1 week old small tumor in the pancreas in an orthotopic PDA model and b) very early pre-neoplastic lesions (PanIN lesions) that develop in the spontaneous PDA model before progression to adenocarcinoma. Thus, TAB004 is a promising antibody to deliver imaging agents directly to the pancreatic tumor microenvironment, significantly affecting early detection of PDA.

Using a morphological‐behavior model to conduct sensitivity experiments, we investigate the sea level rise response of a complex coastal environment to changes in a variety of factors. Experiments reveal that substrate composition, followed in rank order by substrate slope, sea level rise rate, and sediment supply rate, are the most important factors in determining barrier island response to sea level rise. We find that geomorphic threshold crossing, defined as a change in state (e.g., from landward migrating to drowning) that is irreversible over decadal to millennial time scales, is most likely to occur in muddy coastal systems where the combination of substrate composition, depth‐dependent limitations on shoreface response rates, and substrate erodibility may prevent sand from being liberated rapidly enough, or in sufficient quantity, to maintain a subaerial barrier. Analyses indicate that factors affecting sediment availability such as low substrate sand proportions and high sediment loss rates cause a barrier to migrate landward along a trajectory having a lower slope than average barrier island slope, thereby defining an “effective” barrier island slope. Other factors being equal, such barriers will tend to be smaller and associated with a more deeply incised shoreface, thereby requiring less migration per sea level rise increment to liberate sufficient sand to maintain subaerial exposure than larger, less incised barriers. As a result, the evolution of larger/less incised barriers is more likely to be limited by shoreface erosion rates or substrate erodibility making them more prone to disintegration related to increasing sea level rise rates than smaller/more incised barriers. Thus, the small/deeply incised North Carolina barriers are likely to persist in the near term (although their long‐term fate is less certain because of the low substrate slopes that will soon be encountered). In aggregate, results point to the importance of system history (e.g., previous slopes, sediment budgets, etc.) in determining migration trajectories and therefore how a barrier island will respond to sea level rise. Although simple analytical calculations may predict barrier response in simplified coastal environments (e.g., constant slope, constant sea level rise rate, etc.), our model experiments demonstrate that morphological‐behavior modeling is necessary to provide critical insights regarding changes that may occur in environments having complex geometries, especially when multiple parameters change simultaneously.

Coastal foredunes form via biophysical feedbacks between sand accretion and burial‐tolerant vegetation and can protect coastlines from hazards such as extreme storms and sea level rise. Predicting how coastal dunes, and the services they provide, will change in the future requires an understanding of the relative roles of the physical and ecological processes that shape their structure and function. Here we assess the relative roles of sand supply, beach morphology, and vegetation in determining foredune morphology, and its change, along a 300‐km stretch of the US Central Atlantic coast. In particular, we used the spatial variability inherent in beaches and dunes of this region to determine the relative importance of shoreline change rate (SCR; a proxy for sand supply to the beach), beach morphology, and grass density of four widespread dune grasses (Uniola paniculata, Ammophila breviligulata, Panicum amarum, and Spartina patens) to foredune morphology metrics (height, width, and aspect ratio) along the North Carolina Outer Banks barrier islands. Foredune morphology and change metrics are correlated with three main factors: multidecadal SCR (1997–2016), beach slope, and dune grass density and species identity. Multidecadal SCR and beach width explained the most variation in, and were positively correlated with, foredune height and width, and were negatively correlated with foredune aspect ratio (height divided by width). In addition, grass density and changes in grass density contributed significantly to foredune morphology change. We found a positive relationship between change in A. breviligulata density and foredune width, which aligns with previous studies on the US Atlantic and Pacific Northwest coasts. Our results demonstrate the interactive roles of beach sand supply and dune grass functional morphology in dune building processes on highly vulnerable coastlines.

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an adjunct used to temporize uncontrolled abdominopelvic hemorrhage. No published clinical data exist that describe average catheter lengths or balloon fill volumes necessary to occlude the aorta. A prospective, single-institution registry was queried for patients who underwent placement of a Prytime ER-REBOA™ catheter. Demographic, catheter, hemodynamic, and morphometric data were measured. Linear regression analyses were performed to identify variables associated with insertion distances and balloon volumes. 45 patients underwent supraceliac REBOA: median catheter insertion distance 45 cm [IQR 42–46], balloon inflation volume 14 mL [IQR 8–19], systolic blood pressure (SBP) augmentation 50 mmHg [IQR 35–55]. 14 patients underwent infrarenal deployment: median catheter insertion distance 28.5 cm [IQR 26.5–32.5], balloon volume 10 mL [IQR 5–15]; SBP augmentation 55 mmHg [IQR 40–65]. Patient body metrics were not associated with catheter length or balloon volume. A wide range of catheter insertion distances and balloon fill volumes were necessary for correct REBOA positioning and occlusion. No single patient metric accurately correlated with catheter distance or balloon volume. Level IV, Prognostic. •Data from this registry were measured in real time during emergent REBOA catheter placements in adult trauma patients.•A wide range of catheter insertion distances were necessary for optimal REBOA positioning in both zone 1 and zone 3.•A wide range of REBOA balloon inflation volumes was necessary to occlude the aorta in both zone 1 and zone 3.•No single patient metric accurately correlated with REBOA catheter insertion distance or balloon fill volume. There has been renewed interest in resuscitative endovascular balloon occlusion of the aorta (REBOA) following the introduction of a new low-profile, guidewire-free catheter. However, its use in actual patients is not well-described in the literature. This research describes a single institution experience, describing catheter lengths and balloon volumes necessary for accurate occlusion. Catheter data are then compared to patient body metrics and linear regression analyses were performed to identify associations.

Coastal dunes arise from feedbacks between vegetation and sediment supply. Species-specific differences in plant functional morphology affect sand capture and dune shape. In this study, we build on research showing a relationship between dune grass species and dune geomorphology on the US central Atlantic Coast. This study seeks to determine the ways in which four co-occurring dune grass species (Ammophila breviligulata, Panicum amarum, Spartina patens, Uniola paniculata) differ in their functional morphology and sand accretion. We surveyed the biogeography, functional morphology, and associated change in sand elevation of the four dune grass species along a 320-kilometer distance across the Outer Banks. We found that A. breviligulata had dense and clumped shoots, which correlated with the greatest sand accretion. Coupled with fast lateral spread, it tends to build tall and wide foredunes. Uniola paniculata had fewer but taller shoots and was associated with ~42% lower sand accretion. Coupled with slow lateral spread, it tends to build steeper and narrower dunes. Panicum amarum had similar shoot densities and associated sand accretion to U. paniculata despite its shorter shoots, suggesting that shoot density is more important than morphology. Finally, we hypothesize, given the distributions of the grass species, that foredunes may be taller and wider and have better coastal protection properties in the north where A. breviligulata is dominant. If under a warming climate A. breviligulata experiences a range shift to the north, as appears to be occurring with U. paniculata, changes in grass dominance and foredune morphology could make for more vulnerable coastlines.

Damage control laparotomy (DCL) is performed for physiologically deranged patients. Recent studies suggest overutilization of DCL, which may be associated with potentially iatrogenic complications. We conducted a retrospective study of trauma patients over a 2-year period that underwent an emergent laparotomy and received preoperative blood products. The group was divided into definitive laparotomy and DCL. A total of 237 received were included: 78 in definitive laparotomy group, 144 in the DCL group, and 15 who died in the operating room. The DCL group was more severely injured and required more transfusions. After propensity score matching, DCL was associated with an 18% increase in hospital mortality, a 13% increase in ileus, and a 7% increase in enteric suture line failure, an 11% increase in fascial dehiscence, and a 19% increase in superficial surgical site infection. The potential overuse of DCL unnecessarily exposes patients to increased morbidity and mortality. •In bleeding patients, damage control laparotomy (DCL) can be life-saving.•In this cohort of bleeding patients, DCL appears overused.•DCL is associated with an increase in multiple complications.•DCL is associated with an 18% increase in mortality.•Overutilization of DCL exposes patients to potentially iatrogenic complications.

Resuscitative endovascular balloon occlusion of the aorta (REBOA) has recently gained popularity as a minimally invasive alternative to open aortic cross-clamping in the management of patients with non-compressible hemorrhage arising below the diaphragm. The purpose of this review is to provide a description of the technical aspects of REBOA use along with an overview of the current animal and clinical data regarding its use.

Barrier islands are complex and dynamic systems that provide critical ecosystem services to coastal populations. Stability of these systems is threatened by rising sea level and the potential for coastal storms to increase in frequency and intensity. Recovery of dune-building grasses following storms is an important process that promotes topographic heterogeneity and long-term stability of barrier islands, yet factors that drive dune recovery are poorly understood. We examined vegetation recovery in overwash zones on two geomorphically distinct (undisturbed vs. frequently overwashed) barrier islands on the Virginia coast, USA. We hypothesized that vegetation recovery in overwash zones would be driven primarily by environmental characteristics, especially elevation and beach width. We sampled species composition and environmental characteristics along a continuum of disturbance from active overwash zones to relict overwash zones and in adjacent undisturbed environments. We compared species assemblages along the disturbance chronosequence and between islands and we analyzed species composition data and environmental measurements with Canonical Correspondence Analysis to link community composition with environmental characteristics. Recovering and geomorphically stable dunes were dominated by Ammophila breviligulata Fernaud (Poaceae) on both islands while active overwash zones were dominated by Spartina patens (Aiton) Muhl. (Poaceae) on the frequently disturbed island and bare sand on the less disturbed island. Species composition was associated with environmental characteristics only on the frequently disturbed island (p = 0.005) where A. breviligulata was associated with higher elevation and greater beach width. Spartina patens, the second most abundant species, was associated with larger sediment grain size and greater sediment size distribution. On the less frequently disturbed island, time since disturbance was the only factor that affected community composition. Thus, factors driving the abundance of dune-building grasses and subsequent recovery of dunes varied between the two geomorphically distinct islands.