Low-Cost Scalable PCB-Based 2-D Transducer Arrays for Volumetric Photoacoustic Imaging.

Photoacoustic (PA) imaging provides deep tissue molecular imaging of chromophores with optical absorption contrast and ultrasonic resolution. Present PA imaging techniques are predominantly limited to one 2D plane per acquisition. 2D ultrasound transducers, required for real-time 3D PA imaging, are high-cost, complex to fabricate and have limited scalability in design. We present novel PCB-based 2D matrix ultrasound transducer arrays that are capable of being bulk manufactured at low-cost without using laborious ultrasound fabrication tools. The 2D ultrasound array specifications are easily scalable with respect to widely available PCB design and fabrication tools at low cost. To demonstrate scalability, we fabricated low (11 MHz) frequency 8x8 matrix array and high (40 MHz) frequency 4x4 matrix array by directly bonding an undiced polyvinylidene fluoride (PVDF) piezoelectric material of desired thickness to the custom designed PCB substrate. Characterization results demonstrate wideband PA receive sensitivity for both low (87%) and high (188%) frequency arrays. Volumetric PA imaging results of light absorbing targets inside optical scattering medium demonstrate improved spatial resolution and field of view with increase in aperture size.

Assessment of Trachyspermum ammi essential oil against Aspergillus flavus, aflatoxin B1 contamination, and post-harvest quality of Sorghum bicolor.

The present investigation explored the antifungal effectiveness of Trachyspermum ammi essential oil (TAEO) against Aspergillus flavus, aflatoxin B1 (AFB1) contamination, and its mechanism of action using biochemical and computational approaches. The GC-MS result revealed the chemical diversity of TAEO with the highest percentage of γ-terpinene (39 %). The TAEO exhibited minimum inhibitory concentration against A. flavus growth (0.5 µL/mL) and AFB1 (0.4 µL/mL) with radical scavenging activity (IC50 = 2.13 µL/mL). The mechanism of action of TAEO was associated with the alteration in plasma membrane functioning, antioxidative defense, and carbon source catabolism. The molecular dynamic result shows the multi-regime binding of γ-terpinene with the target proteins (Nor1, Omt1, and Vbs) of AFB1 biosynthesis. Furthermore, TAEO exhibited remarkable in-situ protection of Sorghum bicolor seed samples against A. flavus and AFB1 contamination and protected the nutritional deterioration. Hence, the study recommends TAEO as a natural antifungal agent for food protection against A. flavus mediated biodeterioration.

Feasibility of USG-Guided Objective Initial Assessment of Pupillary Size and Pupillary Reflexes Versus Clinical Examination in Patients With Altered Mental Status: A Cross-Sectional Study.

BACKGROUND: Pupillary assessment is an important part of the neurological assessment which provides vital information in critically ill patients. However, clinical pupillary assessment is subjective. The ultrasound-guided pupillary examination is objective. There are limited pieces of literature regarding its use in assessing patients with altered mental status. So, we studied the extent of agreement of B-mode ultrasound with clinical examination for assessment of the pupillary size and reflex in patients with altered mental status. OBJECTIVES: The primary objective was to determine the extent of agreement between clinical examination and ultrasound-based examination for assessing pupillary reflex and size in patients with altered mental status in two settings (trauma and non-trauma patients). METHODS: Exactly 200 subjects (158 males, mean [range] age 43.56 [18-92 years]) with no history of partial globe rupture or dementia were included in this cross-sectional study from March 2019 to March 2020. B-mode ultrasound was performed with the subject's eyes closed using a 7-12 MHz linear probe and a standardized light stimulus. ICC score, paired t-test, kappa, Wilcoxon signed-rank test, and Bland-Altman plots were used for statistical analysis. RESULTS: The clinical-USG agreement for pupillary light reflex examination (Pupillary Diameter [PD] at rest, after direct light stimulation [Dstim ] and consensual light stimulation [Cstim ]) was excellent (ICC, 0.93-0.96). The Kappa coefficient (0.74 ± 0.07) showed an agreement of 87.36% between clinical and USG examination for pupillary reflex (reactive or non-reactive). CONCLUSION: USG-guided pupillary examination proves to be a better adjunct to neurological assessment in patients with altered mental status.

A Comparative Investigation of Automatic Speech Recognition Platforms for Aphasia Assessment Batteries.

The rehabilitation of aphasics is fundamentally based on the assessment of speech impairment. Developing methods for assessing speech impairment automatically is important due to the growing number of stroke cases each year. Traditionally, aphasia is assessed manually using one of the well-known assessment batteries, such as the Western Aphasia Battery (WAB), the Chinese Rehabilitation Research Center Aphasia Examination (CRRCAE), and the Boston Diagnostic Aphasia Examination (BDAE). In aphasia testing, a speech-language pathologist (SLP) administers multiple subtests to assess people with aphasia (PWA). The traditional assessment is a resource-intensive process that requires the presence of an SLP. Thus, automating the assessment of aphasia is essential. This paper evaluated and compared custom machine learning (ML) speech recognition algorithms against off-the-shelf platforms using healthy and aphasic speech datasets on the naming and repetition subtests of the aphasia battery. Convolutional neural networks (CNN) and linear discriminant analysis (LDA) are the customized ML algorithms, while Microsoft Azure and Google speech recognition are off-the-shelf platforms. The results of this study demonstrated that CNN-based speech recognition algorithms outperform LDA and off-the-shelf platforms. The ResNet-50 architecture of CNN yielded an accuracy of 99.64 ± 0.26% on the healthy dataset. Even though Microsoft Azure was not trained on the same healthy dataset, it still generated comparable results to the LDA and superior results to Google's speech recognition platform.

Performance Evaluation of Machine Learning Frameworks for Aphasia Assessment.

Speech assessment is an essential part of the rehabilitation procedure for patients with aphasia (PWA). It is a comprehensive and time-consuming process that aims to discriminate between healthy individuals and aphasic patients, determine the type of aphasia syndrome, and determine the patients' impairment severity levels (these are referred to here as aphasia assessment tasks). Hence, the automation of aphasia assessment tasks is essential. In this study, the performance of three automatic speech assessment models based on the speech dataset-type was investigated. Three types of datasets were used: healthy subjects' dataset, aphasic patients' dataset, and a combination of healthy and aphasic datasets. Two machine learning (ML)-based frameworks, classical machine learning (CML) and deep neural network (DNN), were considered in the design of the proposed speech assessment models. In this paper, the DNN-based framework was based on a convolutional neural network (CNN). Direct or indirect transformation of these models to achieve the aphasia assessment tasks was investigated. Comparative performance results for each of the speech assessment models showed that quadrature-based high-resolution time-frequency images with a CNN framework outperformed all the CML frameworks over the three dataset-types. The CNN-based framework reported an accuracy of 99.23 ± 0.003% with the healthy individuals' dataset and 67.78 ± 0.047% with the aphasic patients' dataset. Moreover, direct or transformed relationships between the proposed speech assessment models and the aphasia assessment tasks are attainable, given a suitable dataset-type, a reasonably sized dataset, and appropriate decision logic in the ML framework.

Sudden cardiac death: epidemiology, pathogenesis and management.

Sudden cardiac death (SCD) is an unexpected sudden death due to a heart condition, that occurs within one hour of symptoms onset. SCD is a leading cause of death in western countries, and is responsible for the majority of deaths from cardiovascular disease. Moreover, SCD accounts for mortality in approximately half of all coronary heart disease patients. Nevertheless, the recent advancements made in screening, prevention, treatment, and management of the underlying causes has decreased this number. In this article, we sought to review established and new modes of screening patients at risk for SCD, treatment and prevention of SCD, and the role of new technologies in the field. Further, we delineate the current epidemiologic trends and pathogenesis. In particular, we describe the advancement in molecular autopsy and genetic testing, the role of target temperature management, extracorporeal membrane oxygenation (ECMO), cardiopulmonary resuscitation (CPR), and transvenous and subcutaneous implantable cardioverter devices (ICDs).

Fabrication of volatile compounds loaded-chitosan biopolymer nanoparticles: Optimization, characterization and assessment against Aspergillus flavus and aflatoxin B1 contamination.

The study demonstrates the use of chitosan as a carrier agent of designed antifungal formulation (CME 4:1:1) based on a combination of plant compounds such as trans- cinnamaldehyde (C), methyl eugenol (M), and estragole (E). The formulation was encapsulated inside the chitosan biopolymer nanomatrix (Ne-CME) and characterized by SEM, FTIR, and XRD. The Ne-CME exhibited enhanced antifungal and aflatoxin B1 inhibitory effect compared to the individual compounds and unencapsulated form. Ne-CME (0.04 µl/ml) caused significant protection of Piper longum fruit from fungal (90.05%) and aflatoxin B1 (100%) contamination and had no significant negative effects on its nutritional properties. In addition, the probable antifungal mechanism of Ne-CME was investigated using in-silico (effect on Omt-1 and Vbs structural genes of AFB1 biosynthesis) and biochemical (perturbances in the cell membrane, carbohydrate catabolism, methyl-glyoxal, mitochondrial membrane potential, and antioxidant defense system) assay.

An Efficient Deep Learning Based Method for Speech Assessment of Mandarin-Speaking Aphasic Patients.

Speech assessment is an important part of the rehabilitation process for patients with aphasia (PWA). Mandarin speech lucidity features such as articulation, fluency, and tone influence the meaning of the spoken utterance and overall speech clarity. Automatic assessment of these features is important for an efficient assessment of the aphasic speech. Hence, in this paper, a standardized automatic speech lucidity assessment method for Mandarin-speaking aphasic patients using a machine learning based technique is presented. The proposed assessment method adopts the Chinese Rehabilitation Research Center Aphasia Examination (CRRCAE) standard as a guideline. Quadrature based high-resolution time-frequency images with a convolutional neural network (CNN) are utilized to develop a method that can map the relationship between the severity level of aphasic patients' speech and the three speech lucidity features. The results show a linear relationship with statistically significant correlations between the normalized true-class output activations (TCOA) of the CNN model and patients' articulation, fluency, and tone scores, i.e., 0.71 (p < 0.001), 0.60 (p < 0.001) and 0.58 (p < 0.001), respectively. The linearity of the proposed Mandarin aphasic speech assessment method and its significant correlation with the speech severity levels show the efficacy of the method in predicting the severity of impaired Mandarin speech. The outcome of this research envisages assisting speech-language pathologists in Mandarin-speech impairment assessment and promoting early support discharge; hence could alleviate the stress that the healthcare system is currently experiencing in China nationwide. The framework of the proposed Mandarin aphasic speech assessment method can be readily extended to other languages.

Managing central venous access during a health care crisis.

OBJECTIVE: During the COVID-19 pandemic, central venous access line teams were implemented at many hospitals throughout the world to provide access for critically ill patients. The objective of this study was to describe the structure, practice patterns, and outcomes of these vascular access teams during the COVID-19 pandemic. METHODS: We conducted a cross-sectional, self-reported study of central venous access line teams in hospitals afflicted with the COVID-19 pandemic. To participate in the study, hospitals were required to meet one of the following criteria: development of a formal plan for a central venous access line team during the pandemic; implementation of a central venous access line team during the pandemic; placement of central venous access by a designated practice group during the pandemic as part of routine clinical practice; or management of an iatrogenic complication related to central venous access in a patient with COVID-19. RESULTS: Participants from 60 hospitals in 13 countries contributed data to the study. Central venous line teams were most commonly composed of vascular surgery and general surgery attending physicians and trainees. Twenty sites had 2657 lines placed by their central venous access line team or designated practice group. During that time, there were 11 (0.4%) iatrogenic complications associated with central venous access procedures performed by the line team or group at those 20 sites. Triple lumen catheters, Cordis (Santa Clara, Calif) catheters, and nontunneled hemodialysis catheters were the most common types of central venous lines placed by the teams. Eight (14%) sites reported experience in placing central venous lines in prone, ventilated patients with COVID-19. A dedicated line cart was used by 35 (59%) of the hospitals. Less than 50% (24 [41%]) of the participating sites reported managing thrombosed central lines in COVID-19 patients. Twenty-three of the sites managed 48 iatrogenic complications in patients with COVID-19 (including complications caused by providers outside of the line team or designated practice group). CONCLUSIONS: Implementation of a dedicated central venous access line team during a pandemic or other health care crisis is a way by which physicians trained in central venous access can contribute their expertise to a stressed health care system. A line team composed of physicians with vascular skill sets provides relief to resource-constrained intensive care unit, ward, and emergency medicine teams with a low rate of iatrogenic complications relative to historical reports. We recommend that a plan for central venous access line team implementation be in place for future health care crises.

Encapsulation of Bunium persicum essential oil using chitosan nanopolymer: Preparation, characterization, antifungal assessment, and thermal stability.

The present study reports the antifungal, aflatoxin B1 inhibitory, and free radical scavenging activity of chitosan-based nanoencapsulatedBunium persicum Boiss. essential oil (Ne-BPEO). The chemical profile ofBPEO was identified through Gas chromatography mass spectrometry analysis where cuminaldehyde (21.23%), sabinene (14.66%), and γ-terpinen (12.49%) were identified as the major compounds. Ne-BPEO was prepared using chitosan and characterised by Scanning electron microscope (SEM), Atomic force microscope (AFM), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) assay. Ne-BPEO completely inhibited the growth and aflatoxin B1 production at a concentration of 0.3 µL/mL. The antifungal and aflatoxin B1 inhibitory effects were related to decreasing in ergosterol content, leakage of membrane ions (Ca2+, K+, and Mg2+), impairment in carbohydrate catabolism, and functioning of ver-1 gene of A. flavus exposed to Ne-BPEO over the control. In addition, Ne-BPEO exhibited promising free radical scavenging activity through DPPH assay (IC50 12.64 µL/mL) with high thermo-stability. Therefore, chitosan could be used as a carrier agent of plant-based preservative to enhance the shelf-life of food products against A. flavus and aflatoxin B1 contamination.

Inequity in health care delivery in India: the problem of rural medical practitioners.

A considerable section of the population in India accesses the services of individual private medical practitioners (PMPs) for primary level care. In rural areas, these providers include MBBS doctors, practitioners of alternative systems of medicine, herbalists, indigenous and folk practitioners, compounders and others. This paper describes the profile, knowledge and some practices of the rural doctor in India and then discusses the reasons for lack of equity in health care access in rural areas and possible solutions to the problem.