Improving the Acoustic Performance of Linear Multi-Element Transducers

The electro-acoustic performance of transducers has a direct impact on the performance of ultrasound inspections. The signal/noise ratio and the resolution (both axial and lateral) are key factors for detecting and/or proportioning the indications being sought. The signal/noise ratio partly depends on the sensitivity and the signal/noise ratio of the transducer itself. The axial resolution depends on the length of the signal and therefore, for a given maximum frequency, on the damping of the transducer. Sensitivity and damping are often considered antagonistic, as damping traditionally reduces resonance and therefore sensitivity. Earlier studies have demonstrated the advantages gained through using piezocomposite technology to improve this compromise. These two parameters also depend on the acoustic adaptation to the coupling medium (water, plexiglass, rexolite, steel, etc.), and according to the design used, performance deteriorates more or less as one moves further from the nominal use. In addition to sensitivity and the signal/noise ratio, other parameters such as the angular acceptance and resistance to abrasion are sometimes to be integrated in the expected performances. This article presents the recent developments undertaken and tested in the context of improving the acoustic performance of multi-element probes: - Identification of the components that influence performance; - Simulations; - Selection of the configurations that meet the needs of various applications; - The experimental results obtained; - Comparison with the simulations. These studies have led to the development of a design expertise for responding to requests for custom-made, industrial, multi-element probes with improved performance, for production runs from a single item to dozens, even hundreds. The detailed results will be presented, as well as the possibilities for future development

Bostonia. Volume 16

Founded in 1900, Bostonia magazine is Boston University's main alumni publication, which covers alumni and student life, as well as university activities, events, and programs

assessment of pd 1 pd l1 colocalization in hepatocellular carcinoma hcc using bright field double labeling and quantitative digital image analysis

n/

Enhancing self-care adherence in patients with heart failure: a study protocol for developing a theory-based behaviour change intervention using the COM-B behaviour model (ACHIEVE study)

INTRODUCTION: Although international guidelines recommend self-care as an integral part of routine heart failure management, and despite evidence supporting the positive outcomes related to self-care, patients are frequently unable to adhere. Self-care can be modified through behaviour change interventions (BCIs). However, previous self-care interventions have shown limited success in improving adherence to self-care, because they were neither theory-based nor well defined, which precludes the identification of underlying causal mechanisms as well as reproducibility of the intervention. Thus, our aim is to develop an intervention manual that contains theory-based BCIs that are well-defined using eight descriptors proposed to describe BCIs in a standardised way. METHODS AND ANALYSIS: BCIs will be based on statements of findings derived through qualitative meta-summary techniques and a quantitative meta-analysis. These reviews will be used to extract factors (target behaviours) associated with self-care adherence/non-adherence. Extracted target behaviours will be mapped onto the ‘Capability, Opportunity, Motivation and Behaviour’ (COM-B) model to capture the underlying mechanisms involved. To develop approaches for change, the ‘Taxonomy of Behaviour Change Techniques’ will be used to allow effective mapping of the target behaviours onto established behaviour change techniques. Suggested BCIs will then be translated into locally relevant interventions using the Normalisation Process Theory to overcome the difficulties of implementing theoretically derived interventions into practice. Finally, a consensus development method will be employed to fine-tune the content and acceptability of the intervention manual to increase the likelihood of successfully piloting and implementing future BCIs into the German healthcare system. ETHICS AND DISSEMINATION: This study has been reviewed and approved by the Ethics Committee of the Medical Faculty of the Heinrich Heine University Düsseldorf, Germany (Ref #: 2018-30). The results will be disseminated via peer-reviewed journal publications, conference presentations and stakeholder engagement activities. TRIAL REGISTRATION NUMBER: DRKS00014855; Pre-results

Liquid Chromatography Electron Capture Dissociation Tandem Mass Spectrometry (LC-ECD-MS/MS) versus Liquid Chromatography Collision-induced Dissociation Tandem Mass Spectrometry (LC-CID-MS/MS) for the Identification of Proteins

Electron capture dissociation (ECD) offers many advantages over the more traditional fragmentation techniques for the analysis of peptides and proteins, although the question remains: How suitable is ECD for incorporation within proteomic strategies for the identification of proteins? Here, we compare LC-ECD-MS/MS and LC-CID-MS/MS as techniques for the identification of proteins.Experiments were performed on a hybrid linear ion trap–Fourier transform ion cyclotron resonance mass spectrometer. Replicate analyses of a six-protein (bovine serum albumin, apo-transferrin,lysozyme, cytochrome c, alcohol dehydrogenase, and β-galactosidase) tryptic digest were performed and the results analyzed on the basis of overall protein sequence coverage and sequence tag lengths within individual peptides. The results show that although protein coverage was lower for LC-ECDMS/MS than for LC-CID-MS/MS, LC-ECD-MS/MS resulted in longer peptide sequence tags,providing greater confidence in protein assignment

Atp7a determines a hierarchy of copper metabolism essential for notochord development

SummaryThe critical developmental and genetic requirements of copper metabolism during embryogenesis are unknown. Utilizing a chemical genetic screen in zebrafish, we identified small molecules that perturb copper homeostasis. Our findings reveal a role for copper in notochord formation and demonstrate a hierarchy of copper metabolism within the embryo. To elucidate these observations, we interrogated a genetic screen for embryos phenocopied by copper deficiency, identifying calamity, a mutant defective in the zebrafish ortholog of the Menkes disease gene (atp7a). Copper metabolism in calamity is restored by human ATP7A, and transplantation experiments reveal that atp7a functions cell autonomously, findings with important therapeutic implications. The gene dosage of atp7a determines the sensitivity to copper deprivation, revealing that the observed developmental hierarchy of copper metabolism is informed by specific genetic factors. Our data provide insight into the developmental pathophysiology of copper metabolism and suggest that suboptimal copper metabolism may contribute to birth defects

BAsE-Seq: a method for obtaining long viral haplotypes from short sequence reads.

We present a method for obtaining long haplotypes, of over 3 kb in length, using a short-read sequencer, Barcode-directed Assembly for Extra-long Sequences (BAsE-Seq). BAsE-Seq relies on transposing a template-specific barcode onto random segments of the template molecule and assembling the barcoded short reads into complete haplotypes. We applied BAsE-Seq on mixed clones of hepatitis B virus and accurately identified haplotypes occurring at frequencies greater than or equal to 0.4%, with >99.9% specificity. Applying BAsE-Seq to a clinical sample, we obtained over 9,000 viral haplotypes, which provided an unprecedented view of hepatitis B virus population structure during chronic infection. BAsE-Seq is readily applicable for monitoring quasispecies evolution in viral diseases

Kalign2: high-performance multiple alignment of protein and nucleotide sequences allowing external features

In the growing field of genomics, multiple alignment programs are confronted with ever increasing amounts of data. To address this growing issue we have dramatically improved the running time and memory requirement of Kalign, while maintaining its high alignment accuracy. Kalign version 2 also supports nucleotide alignment, and a newly introduced extension allows for external sequence annotation to be included into the alignment procedure. We demonstrate that Kalign2 is exceptionally fast and memory-efficient, permitting accurate alignment of very large numbers of sequences. The accuracy of Kalign2 compares well to the best methods in the case of protein alignments while its accuracy on nucleotide alignments is generally superior. In addition, we demonstrate the potential of using known or predicted sequence annotation to improve the alignment accuracy. Kalign2 is freely available for download from the Kalign web site (http://msa.sbc.su.se/)