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Intussusception is more commonly considered in the pediatric patient with abdominal pain, but can occur in adults as well. Adult patients are more likely to have an underlying intra-abdominal pathology leading to the condition. We present an adult patient presenting with abdominal pain with ileocecal intussusception diagnosed on imaging and confirmed surgically. In this case, appendiceal pathology served as the lead point for the intussusception.

Background. C2 cervical fractures account for approximately 18% of cervical spine injuries. Few studies have examined patients presenting to an emergency department (ED) with this injury relative to demographics, injury mechanism, and hospital course. Objectives. To compare multiple variables of ED patients presenting with these types of injuries. Methods. In this retrospective cohort study, data were obtained from the Trauma Registry of an academic trauma referral center from January 1, 2011, to December 31, 2015. Patients who presented with a C2 fracture were identified. Information regarding the patient’s gender, age, mechanism of injury, associated injuries, if a procedure was required, disposition, and mortality was extracted. Comparative analyses were conducted between cases over or under age 60. Results. Between January 1, 2011, to December 31, 2015, a total of 139 patients with C2 fractures were identified. Most patients were 60 years or older (79%). Of those, 62% were female, and falls were the most common mechanism (78%). Of those under 60, 50% were female and motor vehicle crashes (MVCs) were the most common mechanism (71%). Odontoid fractures comprised 84% of C2 fractures. Only 6% had an associated spinal cord injury. Less than one-third of patients required operative intervention for their spinal injuries, and intervention was more common in older patients. Following admission, 19% of patients required placement into a nursing home or skilled nursing facility. Conclusions. C2 fractures are more common in older adults and usually resulted from falls. Odontoid fractures are most common. Most C2 fractures do not result in neurologic injury, and only a third were treated surgically. However, several patients were unable to return to their homes following their injury.

Injuries to the clavicle and associated structures may involve fractures of the clavicle or injuries to the surrounding joints, usually from a blow to the shoulder. They present with variable signs and symptoms, requiring a thorough history and physical examination. Diagnosis typically involves plain radiographs but more advanced imaging may be required, especially in the case of sternoclavicular joint dislocations. Often, nonoperative management is indicated but, occasionally, surgical intervention is required. Due to the high incidence of clavicle injuries, it is paramount that the primary care physician be able to recognize, diagnose, and manage these injuries.

We have developed epoxy-based, broadband anti-reflection coatings for millimeter-wave astrophysics experiments with cryogenic optics. By using multiple-layer coatings where each layer steps in dielectric constant, we achieved low reflection over a wide bandwidth. We suppressed the reflection from an alumina disk to 10% over fractional bandwidths of 92% and 104% using two-layer and three-layer coatings, respectively. The dielectric constants of epoxies were tuned between 2.06 and 7.44 by mixing three types of epoxy and doping with strontium titanate powder required for the high dielectric mixtures. At 140 Kelvin, the band-integrated absorption loss in the coatings was suppressed to less than 1% for the two-layer coating, and below 10% for the three-layer coating., 5 pages, 5 figures, Submitted to Applied Optics

The dry-cast membrane-formation process is a principal technique by which asymmetric porous membranes as well as dense films can be obtained. Much insight into the fundamental nature of this process can be obtained via real-time measurements of mass and thickness changes. The former requires an equation of state for the density to obtain the average instantaneous film thickness. Optical techniques for the latter such as interferometry and reflectometry usually require transparent samples and good reflecting surfaces; in many cases, such characteristics cannot be obtained. In this article, we report the adaptation of ultrasonic time-domain reflectometry (TDR) for real-time, noninvasive measurement of thickness changes of polymeric films. Ultrasonic TDR does not depend on optical characteristics and is based upon the reflection of longitudinal plane waves at the interface between two media with different acoustic impedances. The technique utilizes the acoustic velocity, which, in general, is a function of temperature and composition. Representative ultrasonic-TDR thickness data are presented for the cellulose acetate (CA)-acetone, CA-acetone-water, and polysulfone (PSf)-tetrahydrofuran systems. Values are compared to those obtained independently using a direct micrometer measurement as well as mass-loss data. In general, the results are in excellent agreement with a maximum error of less than 5%. In addition to overall changes in thickness, preliminary data indicate that ultrasonic TDR can be used to locate the interface between the polymer solution and an opaque solidified region. The latter is a characteristic of polymer systems that undergo a phase separation during solidification. Ultrasonic TDR thus appears to be a promising technique that can be applied to a wide range of polymer systems.

Background: Current literature supports the use of the three-view plain-radiograph series supplemented, when necessary, with helical computed tomography to evaluate the cervical spine in patients who have sustained trauma injury. The purpose of this study was to determine if helical computed tomography alone can be used to evaluate the cervical spine for acute osseous injury following high-energy trauma, thus eliminating the need to make radiographs. Methods: Patients were prospectively evaluated with helical computed tomography scanning of the cervical spine and standard three-view plain radiography. At a later date, the plain radiographs and computed tomography scans were independently reviewed by two radiologists who were blinded to both the initial interpretation and the interpretation of the corresponding study. The radiologists documented whether the plain radiographs were adequate and whether they showed an acute process. The findings in the study were compared with the initial findings and, when necessary, with the discharge summaries to determine if an injury had been identified. The accuracy of the plain radiographs, of the plain radiographs that had been deemed adequate, and of helical computed tomography used alone was ascertained. Results: Plain radiographs and helical computed tomography scans were made for 407 patients, and traumatic injuries were identified in fifty-eight of them. Plain radiographs alone were adequate for 194 (48%) of the 407 patients. Plain radiographs had a sensitivity of 45%, a specificity of 97%, a positive predictive value of 74%, and a negative predictive value of 91%. Adequate plain radiographs had a sensitivity of 52%, a specificity of 98%, a positive predictive value of 81%, and a negative predictive value of 93%. Helical computed tomography had a sensitivity and specificity of 98%, a positive predictive value of 89%, and a negative predictive value of >99%. The sensitivity, positive predictive value, and negative predictive value of adequate plain radiographs differed significantly from those of helical computed tomography alone (p < 0.001). Twelve (48%) of twenty-five adequate plain radiographs of patients in whom an injury had been identified on computed tomography missed that injury. Helical computed tomography alone missed one (2%) of the fifty-eight injuries. Conclusions: Although helical computed tomography has a limited ability to detect pure ligamentous injury, it can be safely used without plain radiographs to evaluate the cervical spine for osseous abnormalities such as fractures and dislocations after high-energy trauma. Level of Evidence: Diagnostic Level I. See Instructions to Authors for a complete description of levels of evidence.

Sorted patterned ground refers to polygons, nets, or stripes defined by rocky borders which are the result of sorting in soil subjected to frost action. This paper presents a model in which convection cells, driven by unstable density stratification in the aqueous phase, result in uneven melting of the underlying ice front during thawing. The resulting undulatory ice front with regularly spaced peaks and troughs provides the pattern which results in the regularity observed for certain types of patterned ground. In addition, the model predicts the width to depth-of-sorting ratio for both polygons and stripes, and explains the characteristic hexagonal shape of sorted polygons, the transition from sorted polygons to sorted stripes on sloped terrain, and the formation of sorted polygons under water. The predicted ratio of width to depth-of-sorting of 3.81 for sorted polygons is compared with the ratio of width to depth-of-sorting of 3.57 found from a linear regression analysis of 18 field study data.

Today, the leading technology for new desalination installations uses reverse osmosis (RO) membranes. The current generation of RO membranes is of sufficiently high permeability that further significant improvement in RO membrane permeability is less likely to be the primary driver for a major reduction in the cost of desalination but should arise from a variety of other process improvements. As the primary energy use in an RO system is the power required for the high pressure to pump the feed water and is directly related to the feed pressure and flow rate, savings can come in the energy costs in pre‐empting fouling problems. In this project, a novel sensor has been developed to provide more reliable information for process monitoring based on a side-stream RO fouling monitor cell simulating flows in the plant termed the ‘canary cell’. The canary cell is found to be representative of the spiral wound module (SWM), which is the most commonly used configuration in the water desalination industry that can serve as an early warning system. Using a non‐invasive method of Ultrasonic Time Domain Reflectometry (UTDR), foulants on the RO membrane can be detected. The UTDR sensor applies an acoustic signal that reflects from interfaces such as membrane and fouling layer in the cell. The method can detect changes in properties over a few microns and are well suited for integration with the ‘canary cell’ to detect incipient fouling. The UTDR sensor has been shown to monitor colloidal fouling in-situ, in real-time and non-destructively that provides evidence for the metastability of colloidal fouling. Various operational parameters are further evaluated to understand and potentially control the onset of metastability. With the usage of acoustic enhancers, the UTDR sensor was further adapted for the detection of the biofouling, which would otherwise be incapable of reflecting the ultrasound wave for detection due to insufficient difference in acoustic impedance since the bulk of biofilms are water medium. The combination with another online sensor, the Feed Fouling Monitor (FFM), further expanded the application of the UTDR sensor to predicting RO fouling through the measurements of foulant thickness and mass-based specific cake resistance. FFM is an adaptation of the Integrity Sensor (IS) that operates by measuring the transmembrane pressure (TMP) across a membrane of a low hydraulic resistance relative to a reference pressure differential. Doctor of Philosophy (CEE)