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Clinical validation of a deep learning-based approach for preoperative decision-making in implant size for total knee arthroplasty
No full textBackground
Orthopedic surgeons use manual measurements, acetate templating, and dedicated software to determine the appropriate implant size for total knee arthroplasty (TKA). This study aimed to use deep learning (DL) to assist in deciding the femoral and tibial implant sizes without manual manipulation and to evaluate the clinical validity of the DL decision by comparing it with conventional manual procedures.
Methods
Two types of DL were used to detect the femoral and tibial regions using the You Only Look Once algorithm model and to determine the implant size from the detected regions using convolutional neural network. An experienced surgeon predicted the implant size for 234 patient cases using manual procedures, and the DL model also predicted the implant sizes for the same cases.
Results
The exact accuracies of the surgeon’s template were 61.54% and 68.38% for predicting femoral and tibial implant sizes, respectively. Meanwhile, the proposed DL model reported exact accuracies of 89.32% and 90.60% for femoral and tibial implant sizes, respectively. The accuracy ± 1 levels of the surgeon and proposed DL model were 97.44% and 97.86%, respectively, for the femoral implant size and 98.72% for both the surgeon and proposed DL model for the tibial implant size.
Conclusion
The observed differences and higher agreement levels achieved by the proposed DL model demonstrate its potential as a valuable tool in preoperative decision-making for TKA. By providing accurate predictions of implant size, the proposed DL model has the potential to optimize implant selection, leading to improved surgical outcomes
Human Facial Age Group Recognizer Using Assisted Bottleneck Transformer Encoder
No full textRecognizing age from facial images has attracted considerable attention because of its wide array of applications and practical utilities. These include support for advertising platforms, access control, forensic objectives, and video surveillance. Efficient facial age recognition for these varied purposes is essential, necessitating smooth operation on low-cost devices or, at the very least, on a CPU to minimize implementation costs. This work proposes a lightweight CNN architecture efficiently integrated with a transformer encoder to perform facial age group recognition. An assisted bottleneck transformer encoder (ABTE) is introduced to enhance the feature extractor, generating only a few parameters and requiring low computation. As a result, the proposed architecture can achieve competitive performance on the two benchmark datasets, UTKFace and FG-NET. Moreover, this recognizer can attain real-time speed at 147 and 136 frames per second (FPS) with a single and double utilization of the ABTE, respectively, on a CPU device with Intel Core i7-9750H 2.6 GHz and 20 GB of RAM while maintaining its performance
Development and validation of risk prediction model for post?donation renal function in living kidney donors
No full textThis study aimed to create and validate a predictive model for renal function following live kidney donation, using pre-donation factors. Accurately predicting remaining renal function post live kidney donation is currently insufcient, necessitating an efective assessment tool. A multicenter retrospective study of 2318 live kidney donors from two independent centers (May 2007-December 2019) was conducted. The primary endpoint was the reduction in eGFR to below 60 mL/min/m26 months post-donation. The primary endpoint was achieved in 14.4% of the training cohort and 25.8% of the validation cohort. Sex, age, BMI, hypertension, preoperative eGFR, and remnant kidney proportion (RKP) measured by computerized tomography (CT) volumetry were found signifcant in the univariable analysis. These variables informed a scoring system based on multivariable analysis: sex (male: 1, female: 0), age at operation (< 30: 0, 30-39: 1, 40-59: 2, ≥ 60: 3), preoperative eGFR (≥ 100: 0, 90-99: 2, 80-89: 4, < 80: 5), and RKP (≥ 52%: 0, < 52%: 1). The total score ranged from 0 to 10. The model showed good discrimination for the primary endpoint in both cohorts. The prediction model provides a useful tool for estimating post-donation renal dysfunction risk, factoring in the side of the donated kidney. It ofers potential enhancement to pre-donation evaluations
Randomized clinical trial to evaluate the efficacy of porcine and bovine collagen membranes
No full text개요
교원질 차폐막은 제거가 필요 없어 환자 건강에 미치는 영향이 낮고 안정적인 결과를 보이기 때문에 골유도재생에 많이 사용되는 막 중 하나이다. 교원질 차폐막은 노출될 가능성이 적고, 부분적 노출이 되더라도 안정적인 결과를 나타낸다. 교원질 차폐막은 소, 돼지, 말에서 유래된다. 이러한 차폐막의 효용성은 연구가 잘 되어있지만, 무작위 임상시험은 그 수가 적다. 본 연구의 목적은 구강악안면외과 영역의 임상에서 소 및 돼지 유래의 교원질 차폐막 간의 효과를 비교하는 것이었습니다.
재료 및 방법
비구개낭이나 치근당낭과 같이 악골의 결손부에 골 이식이 필요한 환자가 대상이었다. 연조직으로 완전히 피개가 가능한 결손만 고려되었다. 조절되지 않는 대사 질환, 골조직에 영향을 미치는 약물을 주사 맞은 이력이 있는 환자, 또는 임산부는 제외되었다. 흡연량이 많은 환자 및 치료 부위에서 방사선 치료를 받은 환자는 연구에 제외되었다. 총 12 명의 환자가 선정되었으며 최소 5 회 방문해야 했다. 방문 1, 3 및 5에서 콘빔 컴퓨터 단층촬영, 디지털 모델 스캐닝 자료를 획득했다. 매 방문 마다 파노라마 사진 촬영 및 부작용 평가가 이루어졌다. 방문 2, 3, 4 및 5에서 임상 사진이 촬영되었다. 돼지 유래의 골이 이식되었고, 무작위로 배정된 소 및 돼지 유래의 차폐막이 환자에게 적용되었다. 골 부피 평가 및 차폐막의 효용성 평가를 위하여 임상적, 방사선학적, 그리고 3차우너 분석이 시행되었다. 임상적으로 수술부위의 염증, 감염, 창상열개, 그리고 이물질 반응이 있는지 평가되었다. 콘빔 컴퓨터 단층촬영에서 결손 부위를 포함한 치료 영역이 수동으로 설정되었다. 결손 부위를 포함하는 각 단층에서 골 이식의 가장 바깥쪽 테두리를 연결하여 이식된 골의 부피를 측정했다. 소주골 두께는 골 이식의 연속된 길이의 평균으로 정의하였다. 모든 측면에서 둘러싸인 기공과 외부 구조에 연결된 기공은 각각 폐쇄된 모공과 개방된 모공으로 측정하였다. 모든 모공의 부피는 전체 부피의 백분율로 측정하였다. 연조직 평가는 방문 1과 3에서 얻은 석고 모형의 정보를 비교하여 분석되었다. 모형 스캐닝은 구강내 스캐너(Medit i500 oral scanner, 메가젠, 한국)으로 시행되고 3차원 프로그램(Geomagic Control X, 3D Systems, 미국)으로 분석되었다.
결과
성비는 남녀 각각 9:3이었으며, 나이는 24세에서 73세까지 분포되었다. 평균 연령은 43세였다. 치근단낭(8명) 은 총 모집단의 83%를 구성하는 가장 우세한 조직병리학적 결과였고, 비구개낭의 결과는 두 명이었다. 추적관찰 기간에 염증 및 감염의 소견은 관찰되지 않았다. 통계 처리한 결과 대조군과 실험군 사이에 유의한 차이는 없었다(p>0.05, student’s t-test and Mann-Whitney u-test). 3D 모델을 중첩시켜 연조직 부피를 분석하는 결과에서 각각 5건은 감소 및 변화 없음이었고, 증가한 결과는 2건이었다.
결론
이 연구에서 임상적 및 방사선학적 분석결과 소 유래의 교원질 차폐막과 돼지 유래의 교원질 차폐막 간의 골유도재생술 및 연조직 부피 유지 결과에서 유의할 만한 차이는 없었다. 따라서 본 연구에서 사용된 소 및 돼지 유래의 교원질 차폐막은 임상 적용에서 큰 차이를 보이지 않았다.
중심어: 교원질 차폐막, 골유도재생, 골이식, CBCT, 중첩, 분해|Introduction
Collagen membranes are one of the most popularly used membranes for guided bone regeneration (GBR) because there is no need for removal and it shows lower rate of patient morbidity. It is less likely to be exposed and presents stable results even after partial exposure. The sources of the collagen membrane are porcine, bovine and equine. The efficacies of those collagen membrane are well studied, however, randomized clinical trial is scarce. The purpose of this study was to compare the efficacy of collagen membrane from bovine and porcine in oral and maxillofacial pathologic lesions.
Patient & Methods
Patients who needed bone graft due to jaw bone defect such as nasopalatine cyst and periapical cyst were included in this study. Patients whose bone defects underwent primary closure were included. Patients with uncontrolled metabolic disease, history of bone target agent infusion and pregnant woman were excluded. Heavy smokers and those who received radiation therapy at the treatment site were also unable to participate the study. A total of 12 patients were selected and was required to visit 5 times at minimum. Conebeam computed tomography (CBCT), digital model scanning data were acquired at visits 1, 3, and 5. Panoramic views were taken, and adverse reaction evaluation were performed at each visit. Clinical photos were taken at visits 2, 3, 4, and 5. Porcine bone was grafted and bovine and porcine membranes were randomly allocated for each patients. The evaluation methods were clinical, radiological and 3-dimesional model scanning for volume change and efficacy of collagen membranes. Clinical evaluation included presence of inflammation, infection, presence of dehiscence, and foreign body reaction. The treatment area which contained the defect sites were selected and manually manipulated for CBCT analysis. The grafted volume was measured by connecting the outermost border of bone graft in each CBCT layer containing the defect. Trabecular thickness which stands for bone regeneration were measured in the CBCT scan. Pores that are enclosed from all sides and pores connected to the external structure were respectively measured as closed and open pores. The volume of pores was measured as a percentage of the total volume. Soft tissue volume change was evaluated by comparing the data of the plaster models acquired at visit 1 and 5. Model scanning was performed by an intraoral scanner (Medit i500 oral scanner, MegaGen, Korea) and compared by a 3-dimensional analysis software (Geomagic Control X, 3D Systems, Cary, NC, USA).
Results
The gender ratio was 9:3 for males and females, with an age distribution ranging from 24 to 73 years. Periapical cysts (n=10) were the most dominant histopathological result composing 83% of the total group followed by nasopalatine cyst (n=2). No signs of infection or inflammation were presented during follow-up periods. There was no statistical difference between the porcine and bovine membrane groups (p>0.05 on the student’s t-test and Mann-Whitney u-test) from the CBCT data. In the analysis of soft tissue volume in superimposition with 3D models, decreasing and no changing results were 5 cases each, and increasing results were 2 cases.
Conclusion
The results of GBR and soft tissue volume maintenance in the porcine and bovine membrane group showed no significant difference in clinical and radiologic analysis. Therefore, the bovine and porcine membranes used in the study showed no significant difference in clinical application.
Keywords: collagen membrane, guided bone regeneration, bone graft, CBCT, superimposition, degradationMaste
Variation of heart rate during listening to music
No full text음악은 인간의 감정과 긴밀한 연관성을 가지며, 다양한 분야에서 음악의 효과와 응용 가능성을 탐구하기 위해 음악과 감정의 관계를 연구하고 있다. 최근, 이러한 주관적인 감정에 대한 척도를 뇌신호와 같은 생체신호에 기반하여 정량화 하는 연구가 시도되고 있다. 본 연구에서는 음악 청취 시 변화하는 감정이 심박수에 어떤 형태로 발현되는지에 관한 상관 관계를 분석하여 심박수가 감정의 변화를 예측할 수 있는 객관적인 지표인지를 연구하였다. 음악 청취 시 심 전도를 측정하며, 음악 청취 후 선호도, 친숙도, 각성도, 정서가의 정서적 특성을 리커트 척도 점수로 평가하여 음악 청취 시 나타나는 정서적 특성에 따른 심박수의 변화를 분석하였다. 청취 음악에 대해 낮은 선호, 높은 각성, 부정적 정서가의 특성을 보인 경우 차이심박수가 작았으며, 높은 선호, 낮은 각성, 긍정적 정서가의 특성을 보인 경우 차이심박수가 상대 적으로 큰 경향을 보였다. 본 연구 결과 심박수는 음악 청취에 따른 정서적 특성의 변화를 예측할 수 있음을 보여주고 있으며, 향후 다양한 음악 산업에 활용할 수 있으리라 기대한다.
Music has a close connection with human emotions, and this relationship has been explored in various fields. Recently, research has been attempted to quantify these subjective emotions based on biosignals such as brain signals. However, emotional changes when listening to music, as measured by heart rate, which can be easily measured in daily life, are not sufficiently known. In this study, we investigated how changing emotions are expressed through variations in heart rate during music listening. The electrocardiogram (ECG) was measured while participants listened to music, and the emotional characteristics of preference, familiarity, arousal, and valence after listening were evaluated using Likert scale scores to analyze the correlation between changes in heart rate and emotional characteristics. The study confirmed that smaller changes in heart rate were associated with lower preference, higher arousal, and more negative emotional valence, while larger heart rate differences were associated with higher preference, lower arousal, and more positive emotional valence. This study demonstrates that heart rate can be used to objectively predict emotional changes due to music listening, and it is expected to have applications in various music-related industries in the future
Impact of Communication and Conflict Management on Sustainable Supply Chains: Applying Gottman’s Theories
No full text본 연구는 공급망 내에서 소통과 갈등관리가 만족도와 파트너십에 미치는 영향을 분석한다. 이를 위해한국의 공급망 관리 관련 부서 직원들을 대상으로 설문 조사를 하고 구조 방정식 모델을 사용하여 가설을검증하였다. 분석 결과, 소통과 갈등관리는 공급망 내에서 만족도와 파트너십을 긍정적으로 증진시키는것으로 나타났다. 본 연구는 소통과 갈등관리와 같은 무형적 관리 요소가 공급망 성과를 개선하는 데중요한 역할을 한다는 새로운 관점을 제시한다. 그리고 향후 연구에서는 다양한 산업군과 국가를 대상으로비교 연구를 진행하여 문화적 차이와 산업별 특성을 반영한 보다 폭넓은 연구가 필요함을 시사하였다.
This study explores the impact of communication and conflict management on satisfaction and partnership within the supply chain and their role in fostering a sustainable supply chain. It examines how these factors influence supply chain stability and performance, providing strategic insights for long-term success.
A survey was conducted among supply chain management professionals in Korea, and the hypotheses were tested using SPSS 18.0 and AMOS 18.0 with structural equation modeling.
The findings reveal that communication and conflict management positively affect satisfaction and partnership, enhancing trust and cooperation. These improvements ultimately lead to better supply chain stability and performance.
The study highlights the importance of integrating psychological and sociological constructs into supply chain management. Future research could investigate the role of emotional intelligence in leadership and assess "relational health" across supply chain links.
This research underscores how intangible factors like communication and conflict management strengthen relationships and improve supply chain outcomes, offering fresh perspectives for the field
Isolated respiratory tract microorganisms and clinical characteristics in asthma exacerbation of obese patients: a multicenter study
No full textBackground: Viral infection is a risk factor for asthma exacerbation (AE). However, bacterial infections related to AE in adults are poorly known. On the other hand, obese patients with asthma have their own clinical and biological characteristics compared with non-obese patients.
Methods: We investigated the differences in isolated pathogens for AE between obese and non-obese patients with asthma. We included 407 patients with AE from 24 medical centers in Korea. Microorganisms isolated from culture, RT-PCR or serologic tests using lower respiratory tract specimens were retrospectively investigated.
Results: A total of 171 obese and 236 non-obese patients with asthma were included for analysis. Compared to non-obese patients, obese patients were associated with women (77.2% vs. 63.6%), never smoker (82.5% vs. 73.9%), shorter duration of asthma (7.9 ± 8.4 vs. 10.5 ± 10.1 years), less history of pulmonary tuberculosis (8.8% vs. 17.4%), and more comorbidity of allergic rhinitis (48.5% vs. 0.8%). Viral and/or bacterial infections were detected in 205 patients (50.4%) with AE. The numbers of patients with viral only, bacterial only, or both infections were 119, 49, and 37, respectively. The most commonly isolated bacterium was Streptococcus pneumoniae, followed by Pseudomonas aeruginosa and Chlamydia pneumoniae. Obese patients showed a lower incidence of Chlamydia pneumoniae infection. In the non-obese group, bacterial infection, especially Chlamydia pneumoniae infection, was significantly associated with the duration of systemic corticosteroid use (13.6 ± 19.8 vs. 9.7 ± 6.7 days, p = 0.049).
Conclusion: Bacterial infection was associated with a longer period of corticosteroid use in the non-obese group. Acute Chlamydia pneumoniae infection was less associated with obese patients with AE. Further well-designed studies are needed to evaluate microorganisms and the efficacy of antibiotics in patients with AE
Diagnostic Accuracy of Plasma Renin Concentration and Renin Activity in Predicting Mortality and Kidney Outcomes in Patients With Septic Shock and Hypoperfusion or Hypotension: A Multicenter, Prospective, Observational Study
No full textBackground: Lactate is a commonly used biomarker for sepsis, although it has limitations in certain cases, suggesting the need for novel biomarkers. We evaluated the diagnostic accuracy of plasma renin concentration and renin activity for mortality and kidney outcomes in patients with sepsis with hypoperfusion or hypotension.
Methods: This was a multicenter, prospective, observational study of 117 patients with septic shock treated at three tertiary emergency departments between September 2021 and October 2022. The accuracy of renin activity, renin, and lactate concentrations in predicting 28-day mortality, acute kidney injury (AKI), and renal replacement requirement was assessed using the area under the ROC curve (AUC) analysis.
Results: The AUCs of initial renin activity, renin, and lactate concentrations for predicting 28-day mortality were 0.66 (95% confidence interval [CI], 0.55-0.77), 0.63 (95% CI, 0.52-0.75), and 0.65 (95% CI, 0.53-0.77), respectively, and those at 24 hrs were 0.74 (95% CI, 0.62-0.86), 0.70 (95% CI, 0.56-0.83), and 0.67 (95% CI, 0.54-0.79). Renin concentrations and renin activity outperformed initial lactate concentrations in predicting AKI within 14 days. The AUCs of renin and lactate concentrations were 0.71 (95% CI, 0.61-0.80) and 0.57 (95% CI, 0.46-0.67), respectively (P=0.030). The AUC of renin activity (0.70; 95% CI, 0.60-0.80) was also higher than that of lactate concentration (P=0.044).
Conclusions: Renin concentration and renin activity show comparable performance to lactate concentration in predicting 28-day mortality in patients with septic shock but superior performance in predicting AKI
Fabrication and photo/electrochemical properties of cobalt-manganese binary metal sulfides deposited on titania nanotubes: Efficient and stable photoelectrodes for photo-assisted charging supercapacitors
No full textOptically-chargeable supercapacitors with the simultaneous capability of conversion and storage of solar energy into electricity are innovative in the area of renewable energy. Nevertheless, it is very complicated to carry out energy conversion and storage on the same system with an effective and compact design. In addition, such devices are dependent on the same electrode for energy harvest and storage in their compressed form. Thus, the development of energy-efficient photoelectrodes with essential properties of good optical and electrochemical activities is still a challenge. In this work, photoelectrodes with cobalt manganese sulfide (as a promising material for supercapacitors) on TiO2 nanotubes (as stable photoactive electrodes) have been developed as energy-efficient photoelectrodes for photo-supercapacitors. A mixture of KOH and PVA as the separator and electrolyte, respectively, has been used to assemble the all-solid-state asymmetric supercapacitor (ASC) device. This photo-ASC can simultaneously harvest light energy and store charge to provide more effective charge storage performance under light irradiation in comparison with the dark. Light irradiation leads to prolonged discharge time. According to the galvanostatic charge-discharge (GCD) of the device, a capacity enhancement of ∼70 % is obtained at 42.2 mF/cm2 under light irradiation compared to the dark. The capability of light absorption and charge separation efficiency shown by the transition metal sulfide-metal oxide-based photocathodes fulfill the needs for applications in light-chargeable energy storage systems. Furthermore, stable charge storage over long-term cycling (∼4 % capacity loss after 5000 cycles) is shown by this assembled photo-ASC. These results pave the path for the development of promising, self-chargeable energy storage devices with favorable electrochemical performance and stability
Ultrasound standing wave spatial patterning of human umbilical vein endothelial cells for 3D micro-vascular networks formation
No full textGenerating functional and perfusable micro-vascular networks is an important goal for the fabrication of large and three-dimensional tissues. Up to now, the fabrication of micro-vascular networks is a complicated multitask involving several different factors such as time consuming, cells survival, micro-diameter vasculature and strict alignment. Here, we propose a technique combining multi-material extrusion and ultrasound standing wave forces to create a network structure of human umbilical vein endothelial cells within a mixture of calcium alginate and decellularized extracellular matrix. The functionality of the matured microvasculature networks was demonstrated through the enhancement of cell-cell adhesion, angiogenesis process, and perfusion tests with microparticles, FITC-dextran, and whole mouse blood. Moreover, animal experiments exhibited the implantability including that the pre-existing blood vessels of the host sprout towards the preformed vessels of the scaffold over time and the microvessels inside the implanted scaffold matured from empty tubular structures to functional blood-carrying microvessels in two weeks