A direct wavepath-based element localization algorithm to enable flexible ultrasound array imaging.

An algorithm is developed for determining the element locations of a flexible ultrasonic array when applied to a surface of unknown geometry. The algorithm forms a dataset of traveltimes from the direct wavepaths (i.e. rays) between transmitters and receivers, which serves as the input to an optimization scheme that iterates on the array element locations until an objective function is minimized. Once, the relative array locations have been determined, they are used as an input to a phased array ultrasound imaging algorithm. In this study, the total focusing method with full matrix capture is used as a testbed code to demonstrate the benefits of the relative array element localization algorithm. The algorithm is verified by simulation and experimentation.

Analysis of geometric defects in square locally resonant phononic crystals: A comparative study of modeling approachesa).

Phononic crystals can develop defects during manufacturing that alter the desired dynamic response and bandgap behavior. This frequency behavior change can enable successful defect inspection if the characteristic defect response is known. In this study, the behavior of a defective square unit cell comprising a freed and shortened leg is studied using a wave finite element method and an approximate continuous-lumped model to elucidate the defect induced qualitative dynamical features. These metrics are a computationally inexpensive alternative to modeling a defective unit cell within a large pristine array entirely in finite elements. The accuracy of these models is validated by comparing the result to a full finite element model. The impact of a shortened unit cell leg on the behaviors of an infinite array of defective cells and a finite array with a single defect are successfully predicted through dispersion curves and frequency response functions, respectively. These methods reveal defect-induced modes that split the local resonance bandgap of the pristine cell, as well as new anti-resonances resulting from the shortened leg. The study uses both approaches to evaluate the effect of defects in complex phononic crystal geometries and provides a comparative evaluation of the results of each model.

Autologous fat grafting after breast conserving surgery: Breast imaging changes and patient-reported outcome.

BACKGROUND: Autologous fat grafting (AFG) to the breast is known to cause radiologic breast imaging changes. However, these changes have primarily been investigated in breast augmentation settings, whereas the radiologic breast imaging changes after AFG in patients who underwent breast conserving surgery (BCS) have been only sparsely studied. METHODS: All women scheduled to receive AFG to reconstruct BCS defects at our institution between 2014 and 2015 were eligible to participate. Before and after AFG, participants underwent radiologic breast imaging and completed patient-reported outcome measures for body image, aesthetic breast appearance, scar quality, and fear of cancer recurrence. Moreover, an observer evaluated changes in the aesthetic breast appearance and scar quality. RESULTS: Of 49 eligible patients, 42 were included. Participants received 1-3 AFG procedures, with a mean total grafted volume of 135 ± 74 mL. Post-AFG breast imaging was performed 9 ± 5 (range 2-25) months after the final AFG procedure. Comparison of pre- and post-AFG radiologic breast images revealed that 21% had developed calcifications, 85% had developed oil cysts, and 3% had developed increased scarring. Five patients presented with breast imaging changes that required biopsy or additional radiologic evaluation. Significant improvements were observed in breast aesthetic appearance, body image, and scar quality. No major surgical complications occurred. Minor surgical complications were observed in 3% of the patients. CONCLUSIONS: Using AFG to reconstruct BCS defects induces considerable radiologic breast imaging changes. Although the patients experience significant improvements in body image, breast aesthetic appearance, and scar quality, the long-term effect of breast imaging changes warrants further investigation.

Neurophysiological localisation of ulnar neuropathy at the elbow: Validation of diagnostic criteria developed by a taskforce of the Danish Society of clinical neurophysiology.

OBJECTIVE: This study validates consensus criteria for localisation of ulnar neuropathy at elbow (UNE) developed by a taskforce of the Danish Society of Clinical Neurophysiology and compares them to the existing criteria from the American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM). The Danish criteria are based on combinations of conduction slowing in the segments of the elbow and forearm expressed in Z-scores, and difference between the segments in m/s. Examining fibres to several muscles and sensory fibres can increase the certainty of the localisation. METHODS: Diagnostic accuracy for UNE was evaluated on 181 neurophysiological studies of the ulnar nerve from 171 peer-reviewed patients from a mixed patient-group. The diagnostic reference standard was the consensus diagnosis based on all available clinical, laboratory, and electrodiagnostic information reached by a group of experienced Danish neurophysiologists. RESULTS: The Danish criteria had high specificity (98.4%) and positive predictive value (PPV) (95.2%) and fair sensitivity (76.9%). Compared to the AANEM criteria, the Danish criteria had higher specificity (p<0.001) and lower sensitivity (p=0.02). CONCLUSIONS: The Danish consensus criteria for UNE are very specific and have high PPV. SIGNIFICANCE: The Danish criteria for UNE are reliable and well suited for use in different centres as they are based on Z-scores.

Severe adverse effects related to dermal exposure to a glyphosate-surfactant herbicide.

This is a case of severe chemical burns following prolonged accidental exposure to a glyphosate-surfactant herbicide. The patient developed local swelling, bullae and exuding wounds. Neurological impairment followed affecting finger flexion and sensation with reduced nerve conduction. Imaging revealed oedema of the soft tissue and juxta-articular osteopenia, and a causal relationship to exposure is suggested.

Toxicity of Alexandrium lusitanicum to gastropod larvae is not caused by paralytic-shellfish-poisoning toxins.

Laboratory grazing experiments compared ingestion of two subclones of the dinoflagellate Alexandrium lusitanicum by gastropod veliger larvae (Nassarius sp.). While the two prey subclones originated from the same monoclonal isolate of A. lusitanicum, one possessed the ability to produce paralytic-shellfish-poisoning toxins (PSTs), while the other did not. Ingestion rates on the two Alexandrium subclones were not significantly different over a range of prey concentrations (approximately 100 - 660 cells ml-1), indicating that PSTs did not serve as a grazing deterrent for these larvae. However, ingestion rates on both subclones were low at the higher prey concentrations tested. Mortality of the predators also increased linearly with concentration of either subclone. These observations indicated that both A. lusitanicum subclones produced an unknown substance that inhibited and killed the grazers. Veliger mortality was not induced by culture filtrates or lysates, suggesting either that the substance was either highly labile or that contact with intact cells was required. Because toxic algae can produce multiple bioactive substances, experimental demonstrations of alleopathic effects of toxic species should not be assigned to known toxins without supporting evidence. In addition, the results show that the effectiveness of algal grazing deterrents can increase with cell concentration, which may have implications for bloom dynamics.

[EEG and early diagnosis of Angelman syndrome]. / Eeg og tidlig diagnostik af Angelmans syndrom.

The diagnosis of Angelman syndrome has seldom been made in infancy because the typical craniofacial dysmorphism and the typical outbursts of unprovoked laughter are not fully developed before the second and third year of life. Other features such as mental retardation or absence of language, though invariably present, are less obvious in the first year of life. We describe three children in whom consecutive electroencephalographic (EEG) studies show very large amplitude slow activity at 2-3/s, often rhythmic, usually occurring in prolonged runs and often more prominent posteriorly, sometimes with spikes or sharp-wave activity, and invariably associated with a diffuse rhythmic activity at 4-6/ s of 200 microvolts. The changes were present as early as six months of life. They preceded development of seizure and occurred much earlier than the craniofacial dysmorphology. It is concluded that methodical use of EEG in the elucidation of children with developmental disorder and knowledge of the characteristic EEG picture may help to identify patients with Angelman syndrome at an early age and before the clinical features become obvious.

DDAVP and life-threatening diffuse gastric bleeding in uraemia. Case report.

Bleeding in uraemia is frequently manifest as diffuse gastric mucosal haemorrhage. In a patient with acute renal failure, prolonged bleeding time and life-threatening bleeding of this type, effective haemostasis was established with platelet-rich blood products and 1-deamino-8-D-arginine vasopressin (DDAVP).