Simulation of ultrasonic lamb wave generation, propagation and detection for an air coupled robotic scanner

A computer simulator, to facilitate the design and assessment of a reconfigurable, air-coupled ultrasonic scanner is described and evaluated. The specific scanning system comprises a team of remote sensing agents, in the form of miniature robotic platforms that can reposition non-contact Lamb wave transducers over a plate type of structure, for the purpose of non-destructive evaluation (NDE). The overall objective is to implement reconfigurable array scanning, where transmission and reception are facilitated by different sensing agents which can be organised in a variety of pulse-echo and pitch-catch configurations, with guided waves used to generate data in the form of 2-D and 3-D images. The ability to reconfigure the scanner adaptively requires an understanding of the ultrasonic wave generation, its propagation and interaction with potential defects and boundaries. Transducer behaviour has been simulated using a linear systems approximation, with wave propagation in the structure modelled using the local interaction simulation approach (LISA). Integration of the linear systems and LISA approaches are validated for use in Lamb wave scanning by comparison with both analytic techniques and more computationally intensive commercial finite element/difference codes. Starting with fundamental dispersion data, the paper goes on to describe the simulation of wave propagation and the subsequent interaction with artificial defects and plate boundaries, before presenting a theoretical image obtained from a team of sensing agents based on the current generation of sensors and instrumentation

Factors Affecting Healing in the Treatment of Hidradenitis Suppuritiva

Background: Hidradenitis suppurativa (HS) is a chronic and debilitating condition which causes recurrent painful nodules. Patients often progress to develop subdermal abscesses, chronic induration, and suppurative draining sinus tracts. HS causes significant debility and morbidity in patients’ body image, and overall quality of life. Despite this, there is typically a 5-­14 year delay in diagnosis from symptom onset. Treatment of HS depends on disease stage, goals of care, access to care, and frequency of symptoms. We have developed a hidradenitis suppurativa multidisciplinary program (HSMP). We present our experience with surgical treatment for patients with HS who follow in the HSMP. Methods: We retrospectively reviewed the outcomes of all patients referred through the HSMP for surgical treatment to plastic surgery at a single institution from January 2013­December 2015. Inclusion criteria included adults with a diagnosis of HS and exclusion criteria included patients with less than 2 years follow up after surgery. Types of surgical interventions included incision and drainage with fulguration, excision with wound left open, and excision with primary repair. Demographic data, participation in a multidisciplinary program, type of surgery, healing rates, and potential factors contributing to wound healing were retrospectively reviewed in all cases using multivariate analysis. Results: Two hundred forty ­eight patients met inclusion criteria with a total of 810 involved sites. Overall, 59% of patients had Hurley stage 3 disease at the time of surgery. Healing rates of 80% were observed in stage 1 and 2 and 74% observed in stage 3. Hurley stage was not a significant predictor of healing (P = 0.09). Surgical treatment consisted of 38% incision and drainage, 44% excision without closure, and 17% excision with primary closure. Incisional and excisional treatments healed 78% and 79%, respectively, at 2 years. Primarily repaired defects (grafts and flaps) were 68% healed at 2 years. Observed healing rates were uniform regardless of the number of sites involved (P = 0.959). Participation in the multidisciplinary program was the strongest predictor of healing (78% vs 45%, P = 0.004). Gender, age, body mass index, tobacco use, diabetes, pre-surgery hemoglobin, and family history of HS were statistically not significant. Continuation of immune modulating therapy within 2 weeks of surgery was a predictor of reduced healing (odds ratio 0.23, P = 0.004), while holding biologics for at least 2 weeks was not significant (odds ratio 1.99, P = 0.146). Conclusion: Participation in a multidisciplinary program is a strong predictor of long­term success when treating HS. Hurley score and number of involved sites did not correlate with successful healing after surgery. If taking biologics, we identified 2 weeks as an appropriate break from biologics before and after surgical intervention. Healing rates were highest with ablative procedures (incision and drainage, excision) alone.https://scholarlycommons.henryford.com/merf2019clinres/1055/thumbnail.jp

Genomes of uncultured eukaryotes: sorting FACS from fiction

A recent study explores the genome content of uncultured unicellular marine eukaryotes and provides insights about interactions between uncultured eukaryotes and other biological entities

Legionnaires\u27 Disease, A Rising Occurrence in the United States

Legionella pneumophila, a microscopic bacterium usually responsible for a number of illnesses and fatalities, can eliminate a local population, a region or even a nation. In 1976, L. pneumophila was first discovered due to a number of cases presenting with pneumonia-like symptoms. These cases occurred in an isolated population attending an American Legion convention in Philadelphia, Pennsylvania, therefore lending to the name Legionella. Usually found in aquatic environments such as lakes, streams, cooling towers, air conditioning systems and hot tubs, its ability to thrive in artificial and natural environments makes it an ideal bacterium. L. pneumophila can be transmitted via inhaling aerosols that contain the pathogen. After inhalation, the alveolar macrophages phagocytize the pathogen which then serves as its host Virulence factors such as lipopolysaccharides (LPS), are one way the pathogen causes infection, however it can also utilize heat shock protein and surface antigens. Usually with Legionnaires\u27 disease the physical symptoms consist of high fever, malaise, muscle aches, rigors, confusion, headache and diarrhea which categorizes this pathogen as causing an atypical pneumonia. Since L. pneumophila may be associated with travel-related infections, it is hard to track and isolate travel-associated incident clusters because the symptoms present themselves after returning from travel. In regard to diagnosis, this disease has five available techniques to confirm that the patient is in fact positive for L. pneumophila. Programs such as the Environmental Legionella Isolation Techniques Evaluation Program (ELITE) have been started by the Centers for Disease Control and Prevention (CDC) in order to decrease outbreak incidences. Additionally, the current recommendations for the management of Legionnaires\u27 disease adapted from the CDC have been summarized into a flow chart which may help clinical decisions in the treatment of this disease

Perianal Pigmented Variant of Dermatofibrosarcoma Protuberans

Dermatofibrosarcoma protuberans (DFSP) is a low-to-intermediate grade cutaneous sarcoma with reported at 3 per 1,000,000 individuals. It is a locally aggressive tumor which originates in the dermis and invades deeper structures. Up to 90% of cases of DFSP are associated with a translocation between chromosomes 17 and 22. These tumors have a high risk of local recurrence but very rarely exhibit metastatic spread. Several histologic variants exist, including fibrosarcomatous DFSP, and in this case, pigmented DSFP. Pigmented dermatofibrosarcoma protuberans, otherwise also known as a Bednar tumor, is a rare variant of DFSP first described in 1956 which accounts for less than 5% of all DSFP cases. It is distinguished by the presence of melanin containing dendritic cells within the tumor. Histologically, tumor cells are arranged in compact spindle shaped bundles. These tumors may be derived from neuroectodermal cells although no consensus has been reached. DSFP occurs equally in men and women and most commonly occurs in young to middle aged adults. These cutaneous sarcomas typically present on the trunk, back and shoulders as a slow-growing mass or plaque that may be hyperpigmented. Less that 1% present on genitalia, and only two DSFP cases to date have been reported involving the perianal region.https://scholarlycommons.henryford.com/merf2019caserpt/1085/thumbnail.jp

Guaranteeing representation at first Court appearances may be better for defendants, and cheaper for local governments

"If you cannot afford an attorney, one will be appointed for you." It's a familiar phrase, but what does "appointed" really mean? In many jurisdictions in the United States, even after a judge appoints counsel for you, you may spend days or weeks in jail before you actually meet your lawyer. In new research, Alissa Pollitz Worden, Kirstin Morgan, Reveka Shteynberg and Andrew Davies study New York State-funded programs which ensure lawyers are present at defendants’ first court appearances (which is when judges make bail and pretrial detention decisions). They find that the presence of these lawyers may reduce the numbers of people jailed pretrial in misdemeanor cases. This in turn may mean lower incarceration costs for local governments and reduce the social harm of pretrial detention for defendants

Intra-accumbens injections of the adenosine A(2A) agonist CGS 21680 affect effort-related choice behavior in rats

Rationale: Nucleus accumbens dopamine (DA) participates in the modulation of instrumental behavior, including aspects of behavioral activation and effort-related choice behavior. Rats with impaired accumbens DA transmission reallocate their behavior away from food-reinforced activities that have high response requirements, and instead select less-effortful types of food-seeking behavior. Although accumbens DA is considered a critical component of the brain circuitry regulating effort-related processes, emerging evidence also implicates adenosine A2A receptors. Objective: The present work was undertaken to test the hypothesis that accumbens A2A receptor stimulation would produce effects similar to those produced by DA depletion or antagonism. Methods: Three experiments assessed the effects of the adenosine A2A agonist CGS 21680 on performance of a concurrent choice task (lever pressing for preferred food vs. intake of less preferred chow) that is known to be sensitive to DA antagonists and accumbens DA depletions. Results: Systemic injections of CGS 21680 reduced lever pressing but did not increase feeding. In contrast, bilateral infusions of the adenosine A2A receptor agonist CGS 21680 (6.0- 24.0 ng) into the nucleus accumbens decreased lever pressing for the preferred food, but substantially increased consumption of the less preferred chow. Injections of CGS 21680 into a control site dorsal to the accumbens were ineffective. Conclusions: Taken together, these results are consistent with the hypothesis that local stimulation of adenosine A2A receptors in nucleus accumbens produces behavioral effects similar to those induced by accumbens DA depletions. Accumbens adenosine A2A receptors appear to be a component of the brain circuitry regulating effort-related choice behavio

NAISR: A 3D Neural Additive Model for Interpretable Shape Representation

Deep implicit functions (DIFs) have emerged as a powerful paradigm for many computer vision tasks such as 3D shape reconstruction, generation, registration, completion, editing, and understanding. However, given a set of 3D shapes with associated covariates there is at present no shape representation method which allows to precisely represent the shapes while capturing the individual dependencies on each covariate. Such a method would be of high utility to researchers to discover knowledge hidden in a population of shapes. We propose a 3D Neural Additive Model for Interpretable Shape Representation (NAISR) which describes individual shapes by deforming a shape atlas in accordance to the effect of disentangled covariates. Our approach captures shape population trends and allows for patient-specific predictions through shape transfer. NAISR is the first approach to combine the benefits of deep implicit shape representations with an atlas deforming according to specified covariates. Although our driving problem is the construction of an airway atlas, NAISR is a general approach for modeling, representing, and investigating shape populations. We evaluate NAISR with respect to shape reconstruction, shape disentanglement, shape evolution, and shape transfer for the pediatric upper airway. Our experiments demonstrate that NAISR achieves competitive shape reconstruction performance while retaining interpretability.Comment: 20 page