Heart and Lung Sound Measurement Using an Esophageal Stethoscope with Adaptive Noise Cancellation.

In surgeries where general anesthesia is required, the auscultation of heart and lung sounds is essential to provide information on the patient's cardiorespiratory system. Heart and lung sounds can be recorded using an esophageal stethoscope; however, there is huge background noise when this device is used in an operating room. In this study, a digital esophageal stethoscope system was designed. A 3D-printed case filled with Polydimethylsiloxane material was designed to hold two electret-type microphones. One of the microphones was placed inside the printed case to collect the heart and lung sound signals coming out from the patient through the esophageal catheter, the other was mounted on the surface of the case to collect the operating room sounds. A developed adaptive noise canceling algorithm was implemented to remove the operating room noise corrupted with the main heart and lung sound signals and the output signal was displayed on software application developed especially for this study. Using the designed case, the noise level of the signal was reduced to some extent, and by adding the adaptive filter, further noise reduction was achieved. The designed system is lightweight and can provide noise-free heart and lung sound signals.

Position Tracking Techniques Using Multiple Receivers for Anti-Drone Systems.

The need for drone traffic control management has emerged as the demand for drones increased. Particularly, in order to control unauthorized drones, the systems to detect and track drones have to be developed. In this paper, we propose the drone position tracking system using multiple Bluetooth low energy (BLE) receivers. The proposed system first estimates the target's location, which consists of the distance and angle, while using the received signal strength indication (RSSI) signals at four BLE receivers and gradually tracks the target based on the estimated distance and angle. We propose two tracking algorithms, depending on the estimation method and also apply the memory process, improving the tracking performance by using stored previous movement information. We evaluate the proposed system's performance in terms of the average number of movements that are required to track and the tracking success rate.

Effects of Sous-vide Cooking Temperature on Triceps Brachii of Black Goats.

The aim of this study was to determine the effects of sous-vide cooking temperature on the triceps brachii of black goats. Triceps brachii of black goats (12 months) were sous-vide cooked at 55°C, 60°C, and 65°C. The samples were examined for color, scanning electron microscope photographs, sarcomere length, fiber cross-sectional area, cooking yield, shear force, sensory evaluation, and aromatic profile. The results showed that CIE a*, CIE b*, and chroma increased with increasing sous-vide cooking temperature. However, the cooking yield significantly decreased with increasing sous-vide cooking temperature, and the shear forces of the 60°C and 65°C samples showed no significant differences. For sensory evaluation, the 60°C sample showed the highest scores for flavor, texture, and off-flavor. Furthermore, the 60°C sample showed the significantly lowest value of octadienone (aroma characteristics of metallic) intensity (p<0.05). Therefore, sous-vide cooking of triceps brachii of black goats at 60°C is effective in reducing off-flavor and improving tenderness.

Industrial Research and Development on the Production Process and Quality of Cultured Meat Hold Significant Value: A Review.

Cultured meat has been gaining popularity as a solution to the increasing problem of food insecurity. Although research on cultured meat started later compared to other alternative meats, the industry is growing rapidly every year, with developed products evaluated as being most similar to conventional meat. Studies on cultured meat production techniques, such as culturing new animal cells and developing medium sera and scaffolds, are being conducted intensively and diversely. However, active in-depth research on the quality characteristics of cultured meat, including studies on the sensory and storage properties that directly influence consumer preferences, is still lacking. Additionally, studies on the combination or ratio of fat cells to muscle cells and on the improvement of microbiota, protein degradation, and fatty acid degradation remain to be conducted. By actively investigating these research topics, we aim to verify the quality and safety of cultured meats, ultimately improving the consumer preference for cultured meat products.

Correlations between heart sound components and hemodynamic variables.

Although the esophageal stethoscope is used for continuous auscultation during general anesthesia, few studies have investigated phonocardiographic data as a continuous hemodynamic index. In this study, we aimed to induce hemodynamic variations and clarify the relationship between the heart sounds and hemodynamic variables through an experimental animal study. Changes in the cardiac contractility and vascular resistance were induced in anesthetized pigs by administering dobutamine, esmolol, phenylephrine, and nicardipine. In addition, a decrease in cardiac output was induced by restricting the venous return by clamping the inferior vena cava (IVC). The relationship between the hemodynamic changes and changes in the heart sound indices was analyzed. Experimental data from eight pigs were analyzed. The mean values of the correlation coefficients of changes in S1 amplitude (ΔS1amp) with systolic blood pressure (ΔSBP), pulse pressure (ΔPP), and ΔdP/dt during dobutamine administration were 0.94, 0.96, and 0.96, respectively. The mean values of the correlation coefficients of ΔS1amp with ΔSBP, ΔPP, and ΔdP/dt during esmolol administration were 0.80, 0.82, and 0.86, respectively. The hemodynamic changes caused by the administration of phenylephrine and nicardipine did not correlate significantly with changes in the heart rate. The S1 amplitude of the heart sound was significantly correlated with the hemodynamic changes caused by the changes in cardiac contractility but not with the variations in the vascular resistance. Heart sounds can potentially provide a non-invasive monitoring method to differentiate the cause of hemodynamic variations.

Physicochemical Properties of Black Korean Goat Meat with Various Slaughter Ages.

This study was conducted to analyze the physicochemical properties of black goat meat according to the slaughter age (3, 6, 9, 12, 24, 36 months). The moisture content tended to decrease, whereas the fat content, pH, and free amino acid composition tended to increase with increasing slaughter age. The collagen content increased significantly with the increasing slaughter age (p < 0.05). The cooking yield showed a tendency to increase up to 12 months of age, and there was no significant difference after 12 months of age. In all mineral contents, the sample for 12 months of age showed higher values than the others. Considering fatty acid composition, the saturated fatty acid content of the 12-month sample had a lower value than the other samples. However, the unsaturated fatty acid of the 12-month sample had higher values than the other samples. Therefore, the best slaughter age for black goats occurs at 12 months of age when nutrition is excellent.

Tablet-Based Wearable Patch Sensor Design for Continuous Cardiovascular System Monitoring in Postoperative Settings.

Meticulous monitoring for cardiovascular systems is important for postoperative patients in postanesthesia or the intensive care unit. The continuous auscultation of heart and lung sounds can provide a valuable information for patient safety. Although numerous research projects have proposed the design of continuous cardiopulmonary monitoring devices, they primarily focused on the auscultation of heart and lung sounds and mostly served as screening tools. However, there is a lack of devices that could continuously display and monitor the derived cardiopulmonary parameters. This study presents a novel approach to address this need by proposing a bedside monitoring system that utilizes a lightweight and wearable patch sensor for continuous cardiovascular system monitoring. The heart and lung sounds were collected using a chest stethoscope and microphones, and a developed adaptive noise cancellation algorithm was implemented to remove the background noise corrupted with those sounds. Additionally, a short-distance ECG signal was acquired using electrodes and a high precision analog front end. A high-speed processing microcontroller was used to allow real-time data acquisition, processing, and display. A dedicated tablet-based software was developed to display the acquired signal waveforms and the processed cardiovascular parameters. A significant contribution of this work is the seamless integration of continuous auscultation and ECG signal acquisition, thereby enabling the real-time monitoring of cardiovascular parameters. The wearability and lightweight design of the system were achieved through the use of rigid-flex PCBs, which ensured patient comfort and ease of use. The system provides a high-quality signal acquisition and real-time monitoring of the cardiovascular parameters, thus proving its potential as a health monitoring tool.

Effects of Using Soybean Protein Emulsion as a Meat Substitute for Chicken Breast on Physicochemical Properties of Vienna Sausage.

The aim of this study is to determine the effects of using emulsion manufactured with soybeans (ES) to substitute chicken breast in Vienna sausages. Four types of Vienna sausages (S1: 10% ES and 50% chicken, S2: 20% ES and 40% chicken, S3: 30% ES and 30% chicken, and S4: 40% ES and 20% chicken) for this study were made. The pH, color, proximate composition, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), microphotographs, cooking yields, and texture profile analysis of sausages were examined. The pH value of uncooked and cooked sausages increased significantly with increasing ES content (p<0.05). The crude protein contents of S2, S3, and S4 were significantly higher than that of the control (p<0.05). Furthermore, the SDS-PAGE results showed that α-conglycinin, ß-conglycinin, and the acidic subunit of glycinin all increased with increasing ES content. Microphotographs revealed that increasing the ES content decreased the size of fat globules. The cooking yields of samples increased significantly with increasing ES content (p<0.05). The hardness values of ES treated samples were significantly lower than that of the control (p<0.05). Therefore, 30% substitute of chicken breast with ES can improve the quality and structure of Vienna sausage, without inducing critical defects.

Changes in Physico-Chemical and Storage Properties of Dry-Aged Beef Loin Using Electric Field Refrigeration System.

The aim of this study is to establish the dry aging period of beef loin in an electric field refrigeration system. Beef loins (Korea quality grade 2) were dry aged at 0, -1, and -2 °C temperature in an electric field refrigeration system (air velocity, 5 ± 2 m/s) and aging stopped as the value of TPC reached 7 log CFU/g. Samples were examined by aging yield, trimming yield, pH, color, water holding capacity (WHC), cooking yield, shear force, total plate count (TPC), 2-thiobarbituric acid reactive substances (TBARS), and volatile basic nitrogen (VBN). The results for aging yield, trimming yield, redness, yellowness, and chroma decreased with increasing the dry aging period. Contrariwise, those for pH, lightness, hue angle, WHC, and cooking yield increased with the dry aging period. In shear force, the lowest value occurred at four weeks at all temperatures. The results for TPC, TBARS, and VBN increased with aging period, and VBN at 6 weeks at 0 °C and 9 weeks at -1 °C exceed the standard value (20 mg/100 g), while dry aging temperature had an effect on physico-chemical and storage properties by lower temperatures showed slower progress. Therefore, dry aging on an electric field refrigerate system can be used until 4 weeks at 0 °C, 8 weeks at -1 °C, and 10 weeks at -2 °C. However, considering physico-chemical properties, 4 weeks at every temperature is suitable for manufacturing soft dry-aged beef loin.

Quality properties of whole milk powder on chicken breast emulsion-type sausage.

The aim of the study was to determine the effect of whole milk powder (WMP) as heterologous proteins on chicken breast emulsion-type sausages. The quality properties of WMP on such chicken breast emulsion-type sausages were investigated by measuring the proximate composition, pH, color, cooking yield, protein solubility, and by applying other methods, such as texture profile analysis (TPA), microphotograph, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and electronic nose. The crude fat, protein, and ash contents of 15% WMP samples were significantly higher than the control samples (p < 0.05). The redness of the cooked samples significantly increased with an increase in the WMP contents (p < 0.05). The cooking yield of WMP treated samples was significantly higher than the control sample (p < 0.05). Additionally, the hardness, gumminess, and chewiness of WMP treated samples were significantly higher than the control sample (p < 0.05). The sarcoplasmic and myofibrillar proteins of samples containing 15% WMP were significantly higher than the control samples (p < 0.05). The result of SDS-PAGE showed that the C protein, sarcoplasmic protein, actin, and tropomyosin increased with an increase in the WMP contents. The principal component analysis plot of WMP-treated samples was clearly different from that of the control samples. Based on these results, it was predicted that WMP could be useful as heterologous protein on emulsion-type sausage.

Survival Benefit of Surgical Removal of Primary Tumor in Patients With Stage IV Breast Cancer.

BACKGROUND: Several studies have suggested that primary tumor removal improved overall survival for patients with stage IV breast cancer. However, the survival benefit of local treatment remains controversial. The purpose of the present study was to determine whether surgical removal of the primary tumor provides survival benefits to patients with stage IV breast cancer. PATIENTS AND METHODS: We retrospectively reviewed the medical records of 155 patients with an initial diagnosis of stage IV breast cancer at Seoul National University Bundang Hospital from 2003 to 2014. Kaplan-Meier analysis was used to estimate the median survival. The log-rank test was used to compare differences in patient and tumor characteristics. Multivariate Cox regression analysis for survival was used, controlling for potential confounding variables. RESULTS: Of 155 patients with stage IV breast cancer, 95 (61%) underwent surgical removal of the primary tumor. The median follow-up period was 59 months (95% confidence interval [CI], 45-73 months). The median survival was longer for the patients with a better response to chemotherapy (70 vs. 47 months; P = .010) and for those who had undergone surgery (118 vs. 28 months; P < .001) than for those who without a better chemotherapy response or surgery. The median survival of the patients who received radiotherapy was better than that of the patients who did not (65 vs. 39 months; P = .004). Patients with luminal A cancer had a median survival of 118 months, the longest compared with those with other subtypes (P = .001). In addition, patients with distant metastasis at a single site had a longer median survival than did those with multiple metastatic sites. The multivariate Cox regression analysis revealed that fewer distant metastases, surgery of the primary tumor, a better response to chemotherapy, and luminal A subtype were significant independent predictors of survival. CONCLUSION: Our results showed that primary tumor removal was independently associated with improvement in survival. Therefore, surgical management for the primary tumor could be considered more actively in patients with stage IV breast cancer.

Optimal time of initiating adjuvant chemotherapy after curative surgery in colorectal cancer patients.

PURPOSE: Adjuvant chemotherapy is routinely recommended for locally advanced colorectal cancer (CRC). There are very few data for the optimal starting date of adjuvant chemotherapy after the surgery. This study aimed to evaluate the effectiveness of earlier adoption of adjuvant chemotherapy after curative surgery for stage III CRC. METHODS: In this study, 159 patients with stage III CRC, who had undergone a curative resection, were enrolled retrospectively. Patients were categorized into 3 groups representing different timings to initiate the chemotherapy; less than 2 weeks (group 1), 3 to 4 weeks (group 2), and more than 5 weeks (group 3). The overall survival rate (OS) and the relapse-free survival rate (RFS) were analyzed to evaluate the effectiveness of adjuvant chemotherapy. RESULTS: The 5-year OSs of the patients were 73.7% in group 1, 67.0% in group 2, and 55.2% in group 3. The 5-year RFSs of the patients were 48.8% in group 1, 64.7% in group 2, and 57.1% in group 3. There were no significant differences in either the OS or the RFS (P = 0.200, P = 0.405). CONCLUSION: Starting chemotherapy earlier than 6 weeks after surgery does not show any significant difference. Thus, although adjuvant chemotherapy should preferably begin within 6 weeks, the starting date should not necessarily be hastened, and the patient's general condition should be taken into consideration.