An exploratory clinical trial of preoperative non-invasive localization before breast-conserving surgery using augmented reality technology.

PURPOSE: This single-center, randomized, prospective, exploratory clinical trial was conducted to assess the clinical efficacy of an augmented reality (AR)-based breast cancer localization imaging solution for patients with breast cancer. METHODS: This clinical trial enrolled 20 women who were diagnosed with invasive breast cancer between the ages of 19 and 80, had a single lesion with a diameter ≥ 5 mm but ≤ 30 mm, had no metastases to other organs, and had not received prior chemotherapy. All patients underwent mammography, ultrasound, computed tomography, and magnetic resonance imaging for preoperative assessment. Patients were randomly assigned to ultrasound-guided skin marking localization (USL) and AR-based localization (ARL) groups (n = 10 in each group). Statistical comparisons between USL and ARL groups were made based on demographics, radiologic features, pathological outcomes, and surgical outcomes using chi-square and Student t-tests. RESULTS: Two surgeons performed breast-conserving surgery on 20 patients. Histopathologic evaluation of all patients confirmed negative margins. Two independent pathologists evaluated the marginal distances, and there were no intergroup differences in the readers' estimates (R1, 6.20 ± 4.37 vs. 5.04 ± 3.47, P = 0.519; R2, 5.10 ± 4.31 vs. 4.10 ± 2.38, P = 0.970) or the readers' average values (5.65 ± 4.19 vs. 4.57 ± 2.84, P = 0.509). In comparing the tumor plane area ratio, there was no statistically significant difference between the two groups in terms of either reader's mean values (R1, 15.90 ± 9.52 vs. 19.38 ± 14.05, P = 0.525; R2, 15.32 ± 9.48 vs. 20.83 ± 12.85, P = 0.290) or the overall mean values of two readers combined (15.56 ± 9.11 vs. 20.09 ± 13.38, P = 0.388). Convenience, safety, satisfaction, and reusability were all superior in the AR localization group (P < 0.001) based on the two surgeons' responses. CONCLUSION: AR localization is an acceptable alternative to ultrasound-guided skin marking with no significant differences in surgical outcomes.

Evaluation for Parkinsonian Bradykinesia by deep learning modeling of kinematic parameters.

A wearable sensor system is available for monitoring of bradykinesia in patients with Parkinson's disease (PD), however, it remains unclear whether kinematic parameters would reflect clinical severity of PD, or would help clinical diagnosis of physicians. The present study investigated whether the classification model using kinematic parameters from the wearable sensor may show accordance with clinical rating and diagnosis in PD patients. Using the Inertial Measurement Units (IMU) sensor, we measured the movement of finger tapping (FT), hand movements (HM), and rapid alternating movements (RA) in 25 PD patients and 21 healthy controls. Through the analysis of the measured signal, 11 objective features were derived. In addition, a clinician who specializes in movement disorders viewed the test video and evaluated each of the Unified Parkinson's Disease Rating Scale (UPDRS) scores. In all items of FT, HM, RA, the correlation between the linear regression score obtained through objective features (angle, period, coefficient variances for angle and period, change rates of angle and period, angular velocity, total angle, frequency, magnitude, and frequency × magnitude) and the clinician's UPDRS score was analyzed, and there was a significant correlation (rho > 0.7, p < 0.001). PD patients and controls were classified by deep learning using objective features. As a result, it showed a high performance with an area under the curve (AUC) about as high as 0.9 (FT Total = 0.950, HM Total = 0.889, RA Total = 0.888, ALL Total = 0.926. This showed similar performance to the classification result of binary logistic regression and neurologist, and significantly higher than that of family medicine specialists. Our results suggest that the deep learning model using objective features from the IMU sensor can be usefully used to identify and evaluate bradykinesia, especially for general physicians not specializing in neurology.

Pinus densiflora bark extract ameliorates 2,4-dinitrochlorobenzene-induced atopic dermatitis in NC/Nga mice by regulating Th1/Th2 balance and skin barrier function.

Korean red pine (Pinus densiflora) bark has been traditionally used in Korea and other parts of East Asia to relieve inflammatory diseases. Although many studies using P. densiflora bark have been reported, its effect on atopic dermatitis (AD) has not been elucidated. Thus, we investigated whether the P. densiflora bark extract (PBE) has potential to attenuate AD symptoms and elucidated the molecular mechanism. Oral administration of PBE to mice with 2,4-dinitrochlorobenzene (DNCB)-induced AD lessened dermatitis scores and scratching behavior and significantly reduced measures of epidermal thickness, infiltration of mast cells and eosinophils, levels of immunoglobulin E (IgE), and IgG1 /IgG2a ratio in serum. PBE not only inhibited IL-4, IL-5, and IL-13 but also increased IFN-γ in splenic production. Furthermore, PBE significantly suppressed mRNA expression of thymic stromal lymphopoietin and further downregulated the mRNA expression of Th2 and Th17 cytokines such as IL-4, IL-13, IL-17, IL-31, and TNF-α. In addition, the protein expressions of filaggrin, involucrin, and loricrin in lesional skin were recovered by PBE. These results suggest that PBE attenuates DNCB-induced AD via regulating Th1/Th2 balance and skin barrier function.

Blastomonas fulva sp. nov., aerobic photosynthetic bacteria isolated from a Microcystis culture.

Two Gram-stain-negative, aerobic, non-motile, non-spore-forming and rod-shaped bacteria, designated strains T2T and T5, were isolated from a culture of Microcystis from Daejeon, Republic of Korea. Comparative 16S rRNA gene sequence studies placed the new isolates in the class Alphaproteobacteria and, notably, most closely related to Blastomonasaquatica PE 4-5T, Blastomonas natatoria DSM 3183T and Blastomonas ursincola KR-99T showing 99.4 %, 98.2 % and 97.9 % 16S rRNA gene sequence similarities, respectively. The two novel strains shared 100 % similarity with each other. The cells of strains T2T and T5 formed yellow colonies on R2A agar and contained Q-10 as the only ubiquinone, sphingoglycolipid, phosphatidylethanolamine, phosphatidylcholine, and phosphatidylglycerol as major polar lipids, and C17 : 1ω6c, summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), C17 : 1ω8c and C17 : 0 as the major fatty acids (>5 %). The DNA G+C content of the genomes was determined to be 64.2 mol% for strain T2T and 64.4 mol% for strain T5. The DNA-DNA hybridization values of strains T2T and T5 with B.aquatica PE 4-5T, B. natatoria DSM 3183T, and B. ursincola KR-99T were 19.7-42.4 %. Based on the combined genotypic and phenotypic data, we propose that strains T2T and T5 represent a novel species of the genus Blastomonas, for which the name Blastomonas fulvasp. nov. is proposed. The type strain is T2T (=KCTC 42354T=JCM 30467T).

Prognostic Value of Computed Tomography-Detected Extramural Venous Invasion to Predict Disease-Free Survival in Patients With Gastric Cancer.

OBJECTIVE: This study aimed to investigate whether there is a correlation between the computed tomography-detected extramural venous invasion (ctEMVI) and disease-free survival (DFS) in patients with gastric cancer using pathologic lymphovascular invasion as a reference standard. METHODS: We retrospectively reviewed 153 patients with gastric cancer who underwent computed tomography during 1 year. Differences in pathological findings between the ctEMVI-positive and ctEMVI-negative groups were analyzed. Disease-free survival was estimated using the Kaplan-Meier method. Factors affecting DFS were analyzed with the Cox proportional hazard model. RESULTS: The ctEMVI-positive group was correlated more with lymphovascular invasion (P = 0.008). The 1- and 2-year DFS rates were 92% and 80%, respectively, in the ctEMVI-negative group, but 77% and 54%, respectively, in the ctEMVI-positive group. A multivariate analysis revealed that tumor size, ctEMVI, and pathological stage remained associated with DFS (Ps = 0.037, 0.015, and 0.002, respectively). CONCLUSIONS: The ctEMVI was an independent prognostic factor for worse DFS in patients with gastric cancer.

Efficacy and patency of primary stenting for hepatic venous outflow obstruction after living donor liver transplantation.

BACKGROUND: Hepatic venous outflow is important for graft survival in living donor liver transplantation (LDLT). If hepatic venous outflow obstruction occurs, hepatic vein stenting is considered to restore the patency. PURPOSE: To retrospectively evaluate the efficacy and patency of primary hepatic vein stenting for hepatic venous outflow obstruction (HVOO) after LDLT. MATERIAL AND METHODS: Percutaneous interventions, including hepatic vein stent placement with or without balloon angioplasty, were performed in 21 patients who had undergone LDLT and had HVOO confirmed through hepatic venography or manometry, including the patients who had a structural abnormality. Two stents each were inserted in four patients; therefore, the total number of treated anastomoses was 25. Technical success, patency rates, and pressure gradients between hepatic veins and the right atrium were evaluated in 19 patients each. RESULTS: Technical success was achieved in 25 of 26 vessels (96%). The mean interval between operation and stenting was 43 days. After the procedure, the follow-up period was a mean 530 days. The mean pressure gradient decreased from 8.5 mmHg to 2.1 mmHg after treatment (P < 0.01). The patency rates of the 25 vessels were 80% at 1, 2, and 3 years after stent placement. However, middle hepatic vein stenting revealed a low patency rate (all were 36%). Three of seven stents (43%) in the middle hepatic vein occluded during follow-up. CONCLUSION: Percutaneous primary hepatic vein stent replacement is an effective treatment for HVOO after LDLT.

Comparison of the image qualities of filtered back-projection, adaptive statistical iterative reconstruction, and model-based iterative reconstruction for CT venography at 80 kVp.

PURPOSE: To evaluate the subjective and objective qualities of computed tomography (CT) venography images at 80 kVp using model-based iterative reconstruction (MBIR) and to compare these with those of filtered back projection (FBP) and adaptive statistical iterative reconstruction (ASIR) using the same CT data sets. MATERIALS AND METHODS: Forty-four patients (mean age: 56.1 ± 18.1) who underwent 80 kVp CT venography (CTV) for the evaluation of deep vein thrombosis (DVT) during 4 months were enrolled in this retrospective study. The same raw data were reconstructed using FBP, ASIR, and MBIR. Objective and subjective image analysis were performed at the inferior vena cava (IVC), femoral vein, and popliteal vein. RESULTS: The mean CNR of MBIR was significantly greater than those of FBP and ASIR and images reconstructed using MBIR had significantly lower objective image noise (p < .001). Subjective image quality and confidence of detecting DVT by MBIR group were significantly greater than those of FBP and ASIR (p < .005), and MBIR had the lowest score for subjective image noise (p < .001). CONCLUSION: CTV at 80 kVp with MBIR was superior to FBP and ASIR regarding subjective and objective image qualities. KEY POINTS: • MBIR provides superior image quality compared with FBP and ASIR • CTV at 80kVp with MBIR improves diagnostic confidence in diagnosing DVT • CTV at 80kVp with MBIR presents better image quality with low radiation.

The Value of Ki67 in Very Young Women with Hormone Receptor-Positive Breast Cancer: Retrospective Analysis of 9,321 Korean Women.

BACKGROUND: Young breast cancer patients have a poorer prognosis, especially when their tumors are hormone receptor positive. We analyzed the association between Ki67 and age and the impact of these factors on outcomes in hormone receptor-positive breast cancer. METHODS: The records of 9,321 hormone receptor-positive invasive breast cancer patients from three large centers were retrospectively reviewed. Each institution separately assayed Ki67 level immunohistochemically. Univariate and multivariate analysis for recurrence-free survival (RFS) was performed on 4,738 patients from a single center. RESULTS: Ki67 level was inversely proportional to age in all three data sets and was significantly higher for younger patients (p < 0.001, 0.03, and <0.001, respectively). This correlation was seen only in the human epidermal growth factor receptor 2 (HER2)-negative population. Survival analysis showed that both very young age (<35 years) and high Ki67 level (≥10 %) were independent prognostic factors. Although young age was a worse prognostic indicator regardless of HER2 status, Ki67 index was associated with worse prognosis only in HER2-negative patients. When patients were stratified into those with low and high Ki67, young age remained a significant factor for RFS, with hazard ratios in these two Ki67 groups of 2.15 and 2.57, respectively (p < 0.001). Also, the young age/low Ki67 group had significantly poorer RFS than the older age/high Ki67 group (p < 0.001). CONCLUSIONS: Ki67 level was higher in younger patients. However, very young patients had a poorer prognosis regardless of Ki67 level. Unknown biologic factors other than high cell proliferation might play a role in the aggressiveness of hormone receptor-positive breast cancer in very young patients.

Abdominal tuberculosis with periportal lymph node involvement mimicking pancreatic malignancy in an immunocompetent adolescent.

Abdominal tuberculosis manifesting as isolated lymphadenopathy is rare, particularly in children. Tuberculous involvement of the pancreatic head and peripancreatic area can simulate a neoplasm of the pancreatic head. To our knowledge, obstructive jaundice caused by tuberculous lymphadenopathy has not been reported in children or adolescents. Here we present radiologic findings in a case of tuberculous lymphadenopathy that mimicked malignancy of the pancreatic head and caused obstructive jaundice in an immunocompetent adolescent.

Investigating the Impact of Superabsorbent Polymer Sizes on Absorption and Cement Paste Rheology.

This study aims to understand the water retention capabilities of Superabsorbent Polymers (SAPs) in different alkaline environments for internal curing and to assess their impact on the rheological properties of cement paste. Therefore, the focus of this paper is on the absorption capacities of two different sizes of polyacrylic-based Superabsorbent Polymers : SAP A, with an average size of 28 µm, and SAP B, with an average size of 80 µm, in various solutions, such as pH 7, pH 11, pH 13, and cement filtrate solution (pH 13.73). Additionally, the study investigates the rheological properties of SAP-modified cement pastes, considering three different water-to-cement (w/c) ratios (0.4, 0.5, and 0.6) and four different dosages of SAPs (0.2%, 0.3%, 0.4%, and 0.5% by weight of cement). The results showed that the absorption capacity of SAP A was higher in all solutions compared to SAP B. However, both SAPs exhibited lower absorption capacity and early desorption in the cement filtrate solution. In contrast to the absorption results in pH 13 and cement filtrate solutions, the rheological properties, including plastic viscosity and yield stress, of the cement paste with a w/c ratio of 0.4 and 0.5, as well as both dry and wet (presoaked) SAPs, were higher than those of the cement paste without SAP, indicating continuous absorption by SAP. The viscosity and yield stress increased over time with increasing SAP dosage. However, in the mixes with a w/c ratio of 0.6, the values of plastic viscosity and yield stress were initially lower for the mixes with dry SAPs compared to the reference mix. Additionally, cement pastes containing wet SAP showed higher viscosity and yield stress compared to the pastes containing dry SAP.

A prospective randomized controlled trial to determine the safety and efficacy of extracorporeal shock waves therapy for primary prevention of subclinical cardiotoxicity in breast cancer patients without a cardiovascular risk treated with doxorubicin.

Background: Doxorubicin is a highly effective anti-cancer drug that causes left ventricular (LV) dysfunction and induces late-onset cardiomyopathy. However, an effective and clinically applicable preventive treatment is yet to be discovered. Objective: Cardiac-Extracorporeal shockwave therapy (C-ESWT) has been suggested to treat inflammatory and ischemic diseases and protect cardiomyocytes from doxorubicin-induced cardiomyopathy. This study aims to assess the safety and efficacy of C-ESWT in the prevention of subclinical cardiotoxicity. Methods: We enrolled 64 breast cancer patients. C-ESWT group 33 patients were treated with our C-ESWT (200 shots/spot at 0.09 mJ/mm2 for 20 spots, 3 times every six weeks). The efficacy endpoints were the difference in left ventricular global longitudinal strain (LVGLS) change by 2D speckle tracking echocardiography and chemotherapy-related cardiac dysfunction (CTRCD). Echocardiography was performed on the baseline line and every 4 cycles of chemotherapy, followed by a follow-up 3,6 months after chemotherapy to compare the incidence of cardiomyopathy of subclinical LV dysfunction due to chemotherapy between the two groups. Results: Participants averaged 50 ± 9 years in age, 100% female. In the results of follow-up 6 months after the end of chemotherapy, there was a significant difference in delta LVGLS between the C-ESWT group and the control group (LVGLS; -1.1 ± 10.9% vs. -11.5 ± 11.6% p-value; <0.001). A total of 23% (15 patients) of patients developed CTRCD (Control group; 13 vs. C-ESWT group; (2). C-ESWT was performed safely without any serious adverse events. Conclusion: In this prospective study, C-ESWT established efficacy in preventing subclinical cardiotoxicity, especially in breast cancer patients using doxorubicin chemotherapy, and the safety of C-ESWT. Clinical Trial Registration: ClinicalTrials.gov, identifier (NCT05584163).

Prognostic effect of preoperative serum estradiol level in postmenopausal breast cancer.

BACKGROUND: The prognostic role of serum estrogen level in breast cancer patients is unclear. We investigated the prognostic importance of preoperative serum estradiol (E2) level in postmenopausal women according to their estrogen receptor (ER) status. METHODS: The medical records of 313 postmenopausal breast cancer patients who underwent surgery between 2006 and 2008 at a single institution were retrospectively evaluated. Patients who received neoadjuvant chemotherapy, synchronous bilateral breast cancer, or those with metastasis at diagnosis were excluded. Serum E2 and follicular stimulating hormone (FSH) levels were measured by radioimmunoassay and immunoradiometric assay, respectively, within 3 months prior to surgery. After a median follow-up of 52.0 months (11-77 months), 21 women were found to have metastatic disease. RESULTS: The overall, median E2 level was 13.0 pg/ml, and was slightly higher in ER-positive than ER-negative (p=0.69). The mean serum E2 level was significantly higher in patients with metastasis (17.41 ± 8.34 pg/ml) than in those without metastasis (13.54 ± 7.58 pg/ml) (p=0.02). Kaplan-Meier analysis using a cut-off of 13 pg/ml showed that, ER negative (p=0.02) but not ER positive (p>0.05) patients with higher E2 level showed significantly poorer metastasis-free survival. Multivariate analysis showed that, the high E2 level of ER negative tumors was an independent negative prognostic factor for metastasis- free survival (HR, 3.32; 95% CI, 1.05 to 10.51; p=0.04). CONCLUSIONS: Higher preoperative serum E2 level had a negative prognostic effect in postmenopausal women with breast cancer, especially in the ER-negative subgroup.

Variability of Transrectal Shear Wave Elastography in a Phantom Model.

Purpose: This study aimed to assess the variability of transrectal shear wave elastography (SWE) using a designed phantom. Materials and Methods: In a phantom, the SWE values were examined by two radiologists using agarose and emulsion silicone of different sizes (1, 2, and 3 cm) and shapes (round, cubic) at three depths (1, 2, and 3 cm), two region of interest (ROI) and locations (central, peripheral) using two ultrasound machines (A, B from different vendors). Variability was evaluated using the coefficient of variation (CV). Results: The CVs decreased with increasing phantom size. Significant changes in SWE values included; agarose phantom at 3 cm depth (p < 0.001; machine A), 1 cm depth (p = 0.01; machine B), emulsion silicone at 2 cm depth (p = 0.047, p = 0.020; both machines). The CVs increased with increasing depth. Significant changes in SWE values included; 1 cm agarose (p = 0.037, p = 0.021; both machines) and 2 cm agarose phantom (p = 0.047; machine A). Significant differences in SWE values were observed between the shapes for emulsion silicone phantom (p = 0.032; machines A) and between ROI locations on machine B (p ≤ 0.001). The SWE values differed significantly between the two machines (p < 0.05). The intra-/inter-operator agreements were excellent (intraclass correlation coefficient > 0.9). Conclusion: The phantom size, depth, and different machines affected the variability of transrectal SWE.

Factors associated with increased risk of peritoneal seeding after radiofrequency ablation for hepatocellular carcinoma.

PURPOSE: To evaluate the incidence, risk factors, and prognosis associated with peritoneal seeding after percutaneous radiofrequency ablation (RFA) for HCC, focusing on viable tumors after previous locoregional treatment, including TACE and RFA. METHODS: Exactly 290 patients (mean age, 67.9 years ± 9.74; 223 men) with 383 HCCs (mean size, 15.9 mm ± 5.49) who underwent RFA between June 2012 and December 2019 were included in this retrospective study. Among them, 158 had history of previous treatment (mean number, 1.3 ± 1.8) with 109 viable HCCs. Cumulative seeding after RFA was estimated using the Kaplan-Meier method. Independent factors affecting seeding were investigated using multivariable Cox proportional hazards regression analysis. RESULTS: Median follow-up was 1175 days (range: 28-4116). Seeding incidence was 4.1 (12/290) and 4.7% (17/383) per patient and tumor, respectively. The median time interval between RFA and detection of seeding was 785 days (range: 81-1961). Independent risk factors for seeding included subcapsular tumor location (hazard ratio [HR] 4.2; 95% confidence interval [CI] 1.4, 13.0; p = 0.012) and RFA for viable HCC after previous locoregional treatment (HR 4.5; 95% CI 1.7, 12.3; p = 0.003). Subgroup analysis for viable tumors, revealed no significant difference in cumulative seeding rates between the TACE and RFA groups (p = 0.078). Cumulative overall survival rates differed significantly between patients with and without seeding metastases (p < 0.001). CONCLUSION: Peritoneal seeding after RFA is a rare, delayed complication. Subcapsular-located and viable HCC after previous locoregional treatment are potential risk factors for seeding. Seeding metastases could affect the prognosis of patients who cannot receive local therapy.

Liver stiffness measurement using acoustic radiation force impulse (ARFI) elastography and effect of necroinflammation.

BACKGROUND: Acoustic radiation force impulse (ARFI) elastography can be used to assess the degree of liver fibrosis. AIM: We evaluated the performance of ARFI elastography in assessment of liver fibrosis and compared it with the performance of aspartate aminotransferase-to-platelet ratio index (APRI) and transient elastography with Fibroscan (FS). METHODS: We prospectively analyzed 250 consecutive patients who underwent liver biopsy and ARFI from June 2010 to May 2011. Reliable FS values were obtained for 97 (38.8%) patients. RESULTS: The mean age of patients (147 male and 103 female) was 46.6 years. Liver stiffness values obtained by use of ARFI elastography significantly correlated with histological fibrosis stage (R = 0.575, P < 0.001). Area under the receiver operating characteristics curves (AUROCs) of ARFI elastography for predicting significant fibrosis (≥F2) and cirrhosis (F4) was 0.74 (95% confidence interval [CI], 0.64-0.86, P = 0.001) and 0.79 (95% CI, 0.67-0.91, P = 0.001), respectively, and those for APRI were 0.69 (95% CI, 0.58-0.79, P = 0.001) and 0.76 (95% CI, 0.64-0.85, P < 0.001), respectively. The optimum cutoff values for ARFI elastography were 1.13 m/s for ≥F2 and 1.98 m/s for F4; these decreased to 1.09 m/s for ≥F2 and 1.81 m/s for F4 when 131 patients with normal alanine aminotransferase (ALT) were selected. In the sub-group of 97 patients with reliable FS values, the performance in predicting ≥F2 or F4 was equivalent between ARFI elastography and FS. CONCLUSIONS: ARFI elastography is a reliable surrogate marker of liver fibrosis, if its relationship with biochemical markers, for example ALT level, is taken into account.

Chronic destructive pulmonary tuberculosis: assessment of disease activity by computed tomography.

BACKGROUND: Determination of disease activity of chronic destructive pulmonary tuberculosis (TB) on imaging studies can be difficult because several imaging findings due to disease chronicity such as a residual cavity can be misinterpreted as an active disease. PURPOSE: To evaluate computed tomography (CT) findings to predict active disease in patients with chronic destructive pulmonary TB. MATERIAL AND METHODS: CT findings of 36 patients with chronic active destructive pulmonary TB and 78 patients with chronic inactive destructive pulmonary TB were reviewed and their patterns of lung lesions were compared. Statistical comparisons were performed using chi-square and Student's T tests for univariate analyses, and a stepwise logistic regression method was used for multivariate analysis. RESULTS: Based on univariate analyses, cavitary destruction (P = 0.015), non-branching centrilobular nodules (P < 0.001), tree-in-bud pattern (P < 0.001), airspace nodules (P < 0.001), and cavities in other lobes (P = 0.001) were more frequently seen in chronic active destructive pulmonary TB. A stepwise logistic regression analysis demonstrated that tree-in-bud pattern (odds ratio, 52.3; 95% confidence interval, 6.2-437.2; P < 0.001) were significant CT findings associated with active disease. CONCLUSION: Tree-in-bud pattern were the most characteristic CT findings to predict active disease in patients with chronic destructive pulmonary TB.

Promoting Psychological Well-Being at Workplace through Protean Career Attitude: Dual Mediating Effect of Career Satisfaction and Career Commitment.

The management paradigm of SMEs is changing due to the recent Fourth Industrial Revolution and the changing COVID-19 environment. To respond to these changes, companies are focusing on protean career attitude (PCA) and psychological well-being (PWB) of employees to improve corporate performance. Under these circumstances, this study investigated the structural relationship of the dual mediation effects of career commitment and career satisfaction in the relationship between PCA and PWB. To this end, this study targeted 307 employees of Korean small and medium-sized enterprises (SMEs), and the results are as follows. First, PCA was found to have a positive effect on career satisfaction and PCA was found to have a positive effect on career commitment. Second, PCA was found to have a significant effect on PWB. Third, career satisfaction, a parameter of this study, was found to have a positive impact on career commitment; in the relationship between PCA and PWB, the dual mediation effects of career satisfaction and career commitment were found to be significant. Finally, this study provided discussions and theoretical and practical implications based on those results, as well as directions for future research.

Inhibition of monogalactosyldiacylglycerol synthesis by down-regulation of MGD1 leads to membrane lipid remodeling and enhanced triacylglycerol biosynthesis in Chlamydomonas reinhardtii.

BACKGROUND: Membrane lipid remodeling involves regulating the physiochemical modification of cellular membranes against abiotic stress or senescence, and it could be a trigger to increase neutral lipid content. In algae and higher plants, monogalactosyldiacylglycerol (MGDG) constitutes the highest proportion of total membrane lipids and is highly reduced as part of the membrane lipid remodeling response under several abiotic stresses. However, genetic regulation of MGDG synthesis and its influence on lipid synthesis has not been studied in microalgae. For development of an industrial microalgae strain showing high accumulation of triacylglycerol (TAG) by promoting membrane lipid remodeling, MGDG synthase 1 (MGD1) down-regulated mutant of Chlamydomonas reinhardtii (Cr-mgd1) was generated and evaluated for its suitability for biodiesel feedstock. RESULTS: The Cr-mgd1 showed a 65% decrease in CrMGD1 gene expression level, 22% reduction in MGDG content, and 1.39 and 5.40 times increase in diacylglyceryltrimethylhomoserines (DGTS) and TAG, respectively. The expression levels of most genes related to the decomposition of MGDG (plastid galactoglycerolipid degradation1) and TAG metabolism (diacylglycerol O-acyltransferase1, phospholipid:diacylglycerol acyltransferase, and major lipid droplet protein) were increased. The imbalance of DGDG/MGDG ratio in Cr-mgd1 caused reduced photosynthetic electron transport, resulting in less light energy utilization and increased reactive oxygen species levels. In addition, endoplasmic reticulum stress was induced by increased DGTS levels. Thus, accelerated TAG accumulation in Cr-mgd1 was stimulated by increased cellular stress as well as lipid remodeling. Under high light (HL) intensity (400 µmol photons/m2/s), TAG productivity in Cr-mgd1-HL (1.99 mg/L/d) was 2.71 times higher than that in wild type (WT-HL). Moreover, under both nitrogen starvation and high light intensity, the lipid (124.55 mg/L/d), TAG (20.03 mg/L/d), and maximum neutral lipid (56.13 mg/L/d) productivity were the highest. CONCLUSIONS: By inducing lipid remodeling through the mgd1 gene expression regulation, the mutant not only showed high neutral lipid content but also reached the maximum neutral lipid productivity through cultivation under high light and nitrogen starvation conditions, thereby possessing improved biomass properties that are the most suitable for high quality biodiesel production. Thus, this mutant may help understand the role of MGD1 in lipid synthesis in Chlamydomonas and may be used to produce high amounts of TAG.

Two-stage binary classifier for neuromuscular disorders using surface electromyography feature extraction and selection.

If surface electromyography (sEMG) can be used to determine neuromuscular disorders, it can diagnose conditions more easily than needle electromyography. In this study, sEMG during maximum voluntary isometric contraction and repetitive exercise was measured, and normal, myopathy, and neuropathy were classified with high accuracy using these signals. First, a two-stage binary classifier model was constructed to classify the patient group and the normal group and categorize the cases assigned to the patient group into myopathy and neuropathy groups. To this end, features related to muscle activity and muscle fatigue were extracted using activity analysis and frequency analysis of the sEMG signal. Since the features for high performance are different for each classifier, the features with statistical differences in the data of each class were selected for each classifier. The selected features and a two-stage binary classifier were distinguished with an accuracy of 86.9%. This shows an accuracy higher than 82.3%, which was found for the two-stage binary classifier without feature selection and 73.9% of the multi-classifier. Through this, the possibility of using sEMG to diagnose neuromuscular disorders was confirmed.

Two-step microalgal (Coelastrella sp.) treatment of raw piggery wastewater resulting in higher lipid and triacylglycerol levels for possible production of higher-quality biodiesel.

Microalgal treatment of undiluted raw piggery wastewater is challenging due to ammonia toxicity and a deep dark color hampering photosynthesis. To overcome these problems, (1) a microalga (Coelastrella sp.) was isolated from an ammonia-rich environment, (2) the wastewater treatment was divided into two steps: a heterotrophic process followed by a mixotrophic process, and (3) a narrower transparent photobioreactor was employed with higher light intensity in the mixotrophic process. Coelastrella sp. removed 99% of ammonia, 92% of chemical oxygen demand (COD), and 100% of phosphorus during the 4-day process. Acetate in the wastewater relieved the ammonia stress on microalgae and promoted algal lipid and triacylglycerol productivity. Oxidative stability and low-temperature fluidity of triacylglycerols in lipids were improved by means of an altered fatty acid profile. Aside from the overall microalgal treatment performance, the proposed processing of piggery wastewater yielded a material suitable for possible production of algal biodiesel of better quality.