Prediction of sound transmission loss of cylindrical acoustic enclosure using statistical energy analysis and its experimental validation.

In the present work, the sound transmission through a cylindrical shape acoustic enclosure is predicted analytically and verified experimentally. An analytical model is developed, based on the statistical energy analysis (SEA) approach, to examine the transmission loss of a cylindrical acoustic enclosure in different frequency regions, including the low-, intermediate-, and high-frequency ranges. In the developed model, the nonresonant wave response is included in addition to consideration of the resonant response for obtaining more accurate results. It is demonstrated that the developed SEA formulation in this work can compute the resonant as well as the nonresonant sound transmission of the cylindrical acoustic enclosure separately. To validate the analytical model, an experimental setup was developed, and the sound transmission loss of a cylindrical acoustic enclosure was measured using the sound intensity experimental technique. It was found that the analytical results are in good agreement with the measured transmission loss, especially at the panel ring and critical frequencies. The results obtained indicate that the proposed analytical model is efficient to predict the sound transmission loss of cylindrical acoustic enclosures.

Development and Validation of a Deep Learning Strategy for Automated View Classification of Pediatric Focused Assessment With Sonography for Trauma.

OBJECTIVE: Pediatric focused assessment with sonography for trauma (FAST) is a sequence of ultrasound views rapidly performed by clinicians to diagnose hemorrhage. A technical limitation of FAST is the lack of expertise to consistently acquire all required views. We sought to develop an accurate deep learning view classifier using a large heterogeneous dataset of clinician-performed pediatric FAST. METHODS: We developed and conducted a retrospective cohort analysis of a deep learning view classifier on real-world FAST studies performed on injured children less than 18 years old in two pediatric emergency departments by 30 different clinicians. FAST was randomly distributed to training, validation, and test datasets, 70:20:10; each child was represented in only one dataset. The primary outcome was view classifier accuracy for video clips and still frames. RESULTS: There were 699 FAST studies, representing 4925 video clips and 1,062,612 still frames, performed by 30 different clinicians. The overall classification accuracy was 97.8% (95% confidence interval [CI]: 96.0-99.0) for video clips and 93.4% (95% CI: 93.3-93.6) for still frames. Per view still frames were classified with an accuracy: 96.0% (95% CI: 95.9-96.1) cardiac, 99.8% (95% CI: 99.8-99.8) pleural, 95.2% (95% CI: 95.0-95.3) abdominal upper quadrants, and 95.9% (95% CI: 95.8-96.0) suprapubic. CONCLUSION: A deep learning classifier can accurately predict pediatric FAST views. Accurate view classification is important for quality assurance and feasibility of a multi-stage deep learning FAST model to enhance the evaluation of injured children.

Experimental process parameters optimization and in-depth product characterizations for teak sawdust pyrolysis.

Pyrolysis is an efficient thermochemical route to obtain biofuels in the form of bio-oil, biochar and pyrolytic gas from the processing of biomass. Pyrolysis experiments were performed with teak sawdust to determine the yield and main characteristics of solid, liquid and gaseous products. Experiments were carried out in the temperature range of 400-700 °C in 100 °C intervals, nitrogen flow rate of 150-250 mL/min, packed bed height in between 2 and 8 cm and particle size in between 0.18 and 0.60 mm. The maximum bio-oil and biochar yield were observed at 600 °C (48.8%) and 400 °C (37.42%), respectively. Physical properties (viscosity, density, carbon residue, pH and HHV) of bio-oil were determined and the chemical properties were investigated using FTIR and GC-MS. Further, biochar was characterized with proximate, ultimate, HHV, FTIR, SEM-EDX, BET surface area and XRD analysis. Non-condensable gases coming out during pyrolysis were analyzed using gas chromatography and amount of H2, CH4, CO and CO2 were determined. According to characterization results, bio-oil can be used as biofuel after up gradation or as source of valuable chemicals, biochar can be utilized as solid fuel or seems to be suitable in waste stream purification as it has very high BET surface area. In addition, pyrolytic gases have significant amount of methane and hydrogen that provides good combustion properties.

Aggressive Vertebral Body Hemangioma Causing Compressive Myelopathy - Two Case Reports.

INTRODUCTION: Hemangiomas are benign tumors characterized by proliferation of blood vessels. A few hemangiomas are aggressive, characterized by bone expansion and extraosseous extension. These benign tumors may be mistaken for metatasis resulting in unnecessary biopsies, which have a high risk of hemorrhage. These hemangiomas can spread not just into the paraspinal soft tissues but also into the epidural region of the spinal canal causing cord compression and paraparesis. These clinical symptoms can be relieved by surgical decompression of the posterior elements, embolization or radiotherapy. CASE REPORT: In this case report the authors describe the imaging features of two aggressive vertebral body hemangiomas in two patients with back pain. One patient had isolated motor deficit while the other patient had both sensory and motor deficit. On imaging this benign tumor was seen involving both the vertebral body and its posterior elements with paraspinal and epidural extension causing compressive myelopathy. CONCLUSION: Thus, these case reports help identify the characteristic imaging features of an aggressive vertebral body hemangioma, preventing unnecessary and often risky biopsy. The clinical symptoms of the patient can be relieved by surgical decompression of the posterior elements or by radiotherapy. Use of onyx for intraarterial embolization is now believed to be the safest and most efficacious method for treatment of aggressive vertebral body hemangiomas. However, in the absence of definite guidelines, a multicentric study is warranted to prove that embolization with onyx is better than surgery with post-operative radiotherapy.

qFlow Cytometry-Based Receptoromic Screening: A High-Throughput Quantification Approach Informing Biomarker Selection and Nanosensor Development.

Nanosensor-based detection of biomarkers can improve medical diagnosis; however, a critical factor in nanosensor development is deciding which biomarker to target, as most diseases present several biomarkers. Biomarker-targeting decisions can be informed via an understanding of biomarker expression. Currently, immunohistochemistry (IHC) is the accepted standard for profiling biomarker expression. While IHC provides a relative mapping of biomarker expression, it does not provide cell-by-cell readouts of biomarker expression or absolute biomarker quantification. Flow cytometry overcomes both these IHC challenges by offering biomarker expression on a cell-by-cell basis, and when combined with calibration standards, providing quantitation of biomarker concentrations: this is known as qFlow cytometry. Here, we outline the key components for applying qFlow cytometry to detect biomarkers within the angiogenic vascular endothelial growth factor receptor family. The key aspects of the qFlow cytometry methodology include: antibody specificity testing, immunofluorescent cell labeling, saturation analysis, fluorescent microsphere calibration, and quantitative analysis of both ensemble and cell-by-cell data. Together, these methods enable high-throughput quantification of biomarker expression.

Oxidative stress and antioxidants in disease and cancer: a review.

Reactive oxygen species (ROS), highly reactive molecules, are produced by living organisms as a result of normal cellular metabolism and environmental factors, and can damage nucleic acids and proteins, thereby altering their functions. The human body has several mechanisms to counteract oxidative stress by producing antioxidants. A shift in the balance between oxidants and antioxidants in favor of oxidants is termed as "oxidative stress". Paradoxically, there is a large body of research demonstrating the general effect of oxidative stress on signaling pathways, less is known about the initial and direct regulation of signaling molecules by ROS, or what we term the "oxidative interface." This review focuses on the molecular mechanisms through which ROS directly interact with critical signaling molecules to initiate signaling in a broad variety of cellular processes, such as proliferation and survival (MAP kinases and PI3 kinase), ROS homeostasis, and antioxidant gene regulation (Ref-1 and Nrf-2). This review also deals with classification as well as mechanisms of formation of free radicals, examining their beneficial and deleterious effects on cellular activities and focusing on the potential role of antioxidants in preventing and repairing damage caused by oxidative stress. A discussion of the role of phytochemical antioxidants in oxidative stress, disease and the epigenome is included.