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Background This study was conducted as an effort to develop a Korean construction job exposure matrix (KoConJEM) based on 60 occupations recently consolidated by the construction workers mutual aid association for use by the construction industry. Methods The probability, intensity, and prevalence of exposure to 26 hazardous agents for 60 consolidated occupations were evaluated as binary (Yes/No) or four categories (1 to 4) by 30 industrial hygiene experts. The score for risk was calculated by multiplying the exposure intensity by the prevalence of exposure. Fleiss' kappa for each hazardous agent and occupation was used to determine agreement among the 30 experts. The JEM was expressed on a heatmap and a web-based dashboard to facilitate comparison of factors affecting exposure according to each occupation and hazardous agent. Results Awkward posture, heat/cold, heavy lifting, and noise were hazardous agents regarded as exposure is probable by at least one or more experts in all occupations, while exposure to asphalt fumes was considered hazardous in the smallest number of occupations (n = 5). Based on the degree of agreement among experts, more than half of the harmful factors and most occupations showed fair to good results. The highest risk value was 16 for awkward posture for most occupations other than safety officer. Conclusions The KoConJEM provides information on the probability, intensity, and prevalence of exposure to harmful factors, including most occupations employing construction workers; therefore, it may be useful in the conduct of epidemiological studies on assessment of health risk for construction workers. [ABSTRACT FROM AUTHOR]

Detecting thermal faults is critical to the safety of lithium-ion batteries. This article, therefore, proposes a neural network-based approach. The approach relies on the long short-term memory neural network, in conjunction with an alteration to the walk-forward technique, to accurately estimate the surface temperature of the cell. It also relies on a residual monitor to detect the faults in real time. This data-driven method is introduced to expand the available options in thermal fault detection. It offers an easy-to-implement option that does not require expert understanding in battery physics, complex mathematical modeling, and tedious parameter tuning processes. The experimental results demonstrate that this approach can detect thermal faults accurately. It is adaptive to different battery chemistries and form factors, and thanks to its online training capability, it can also automatically retrain itself to capture changes in the battery over time. [ABSTRACT FROM AUTHOR]

This paper uses a physics-based battery model to develop a generic framework to solve optimal charging strategies. The study will also provide insight into the interplay between optimized charging strategies and the battery internal electrochemical kinetics. With a physics-based battery model, a multi-objective optimal control problem is proposed to investigate the charging strategies that optimally trade off the temperature rise, charging time, and loss. First, a fast-charging strategy (minimum time) with the sole purpose of reducing charging time is presented and experimentally validated. The fast-charging strategy can significantly reduce the charging time but causes a high-temperature rise and charging loss. Next, the interplays between temperature rise and charging time, charging loss, and charging time are investigated, respectively. It is found that, in order to reduce the battery temperature during charging, high-current charging at the initial stage should be avoided. Finally, a balanced charging strategy, which considers temperature rise, charging time, and charging loss simultaneously, is developed and analyzed. Experimental results show that the balanced charging strategy has a similar temperature rise as 4C CC/CV charging, but the charging time is reduced by 24.8% and the charging loss is reduced by 56.4%. [ABSTRACT FROM AUTHOR]

The article presents a case study of a previously healthy 14-year-old boy who presented at a medical clinic for the evaluation of recurrent, painless gross hematuria, which was of a two-weeks duration. A physical examination was performed and vital signs were found to be normal. Computed tomography of the boy's abdomen and pelvis was performed which suggested a hemorrhage into cysts. Questions regarding a differential diagnosis and what additional tests should be performed are presented.

The article provides the answers to two questions regarding a differential diagnosis of a case study of a 14-year-old boy who presented at a medical clinic for the evaluation of recurrent, painless gross hematuria.

ENG is an accessory receptor molecule that, in association with TGF-β family receptors types I and II, binds TGF-β1, TGF-β3, activin A, bone morphogenetic protein (BMP)-2, and BMP-7, regulating TGF-β dependent cellular responses. ENG, predominantly expressed in vascular endothelial cells, is also detected in fibroblasts, vascular smooth muscle cells and mesangial cells, among others. Since ENG negatively regulates extracellular matrix (ECM) levels, this molecule may be relevant to DN, which is primarily a disorder of ECM accumulation. 125 T1D pts were ranked based on their electron microscopy estimated rate of mesangial expansion (ME) or ME score (MES). The 20 pts with the highest MES and proteinuria ("fast-track") and the 20 with the lowest MES and normoalbuminuria ("slow-track"), along with 20 healthy controls without D family history, were studied. SF ENG mRNA expression levels were assessed by microarray (Affimetrix HG-U133A GeneChip) and by QRT-PCR. Four subjects from each group, representing a wide range of microarray ENG mRNA expression levels, were selected for western blot using a mouse anti-human ENG monoclonal antibody. Age [36 ± 10 (mean ± SD); 38 ± 8; 41 ± 8 years] and sex (8; 9; 8 males) were similar among "slow-" and "fast-track" pts and controls, respectively. D duration was similar (20 ± 8 vs. 24 ± 7 years), while Ale (8.4 ± 1.2 vs. 9.4 ± 1.5%) and mean blood pressure (85 ± 8 vs. 96 ± 8 mmHg) were lower and glomerular filtration rate (115 ± 13 vs. 72 ± 20 ml/min/1.73m²) higher in "slow" vs. "fast-track" pts. Controls and "fast-track" pts had similar microarmy ENG expression levels (p=0.91), whereas these levels were higher in "slow-track" pts than controls (13=0.015) and "fast-track" pts (p=0.0069). These findings were confirmed by QRT-PCR, where ENG mRNA expression levels were higher in "slow-" (2.07 ± 0.39) than in "fast-track" pts (1.75 ± 0.27; p--0.009) or controls (1.78 ± 0.5; p=0.02). ENG microarmy and QRT-PCR mRNA levels were correlated (r=0.65; p=0.022), and ENG protein expression correlated with ENG mRNA expression levels measured by microarray (r=0.59; p=0.044) and QRT-PCR (r=0.61; p=0.034). Monocyte cell line studies have shown that cells transfected with ENG have lower fibronectin synthesis after TGF-β exposure than control cells. Given this background, our studies are compatible with the idea that "slow-track" T1D pts, strongly protected from DN, have distinct cellular behaviors consistent with reduced ECM production. [ABSTRACT FROM AUTHOR]

Although endothelial dysfunction is known to be associated with the complications of diabetes, including diabetic nephropathy (DN), there are no studies of endothelial cell morphological changes in diabetic patients. Here, we studied endothelial fenestration in relation to other glomerular structural parameters of DN and to glomerular filtration rate (GFR) and albumin excretion rate (AER) in T1DM patients. Research kidney biopsies from 6 (5 males) normal living kidney donors (controls), age 41 (20-50) [median (range)] years; 12 (5 males) non-proteinuric (NP) T1DM patients, age 31 (19-54) years and 6 (2 males) proteinuric (P) T1DM patients, age 34 (26-49) years were studied by electron microscopy. T1DM duration was 20 ± l0 years for NP and 22 ± 7 years for P T1DM patients (not different). Glomerular basement membrane (GBM) width, fractional volume of mesangium [Vv(Mes/gom)], foot process width (FPW) and surface density of capillary endothelial fenestration (SvEF) were measured by stereological methods. GBM width and Vv(Mes/glom) were, as expected, greater in T1DM patients than controls (p<0.05 and p<0.01, respectively). FPW was greater in P patients than NP T1DM patients (p<0.01) or controls (p<0.005) (Table). 41% of the glomerular capillary endothelial coverage was fenestrated in controls. This was reduced by 25% in NP (p=0.01) and by 34% in P (p=0.004) T1D patients, but the difference was not statistically significant between NP and P patients. SvEF was inversely related to Vv(Mes/glom) (r=-0.57, p=0.01), FPW (r=-0.58, p=0.01) and AER (r=0.58, p=0.01) in TlDM patients. Thus, EF is reduced in T1DM patients compared to controls and is related to important glomerular structural parameters of DN (mesangial expansion) and of proteinuria (FPW). Further studies are needed to explore this new structural abnormality in relation to endothelial dysfunction, DN pathogenesis and DN risk. [ABSTRACT FROM AUTHOR]

A novel phenomenological multi-physics model of Lithium-ion battery cells is developed for control and state estimation purposes. The model can capture electrical, thermal, and mechanical behaviors of battery cells under constrained conditions, e.g., battery pack conditions. Specifically, the proposed model predicts the core and surface temperatures and reaction force induced from the volume change of battery cells because of electrochemically- and thermally-induced swelling. Moreover, the model incorporates the influences of changes in preload and ambient temperature on the force considering severe environmental conditions electrified vehicles face. Intensive experimental validation demonstrates that the proposed multi-physics model accurately predicts the surface temperature and reaction force for a wide operational range of preload and ambient temperature. This high fidelity model can be useful for more accurate and robust state of charge estimation considering the complex dynamic behaviors of the battery cell. Furthermore, the inherent simplicity of the mechanical measurements offers distinct advantages to improve the existing power and thermal management strategies for battery management. [ABSTRACT FROM AUTHOR]

[Display omitted] • Deep learning model with domain adaptation is proposed for state-of-charge estimation. • Improvement of data-driven model's generalizability with theoretical guarantees. • Controllable technique for reducing the likelihood of negative transfer learning. • The proposed method outperforms existing deep and transfer learning benchmarks. • The method is robust to operating conditions, aging levels, and battery chemistries. Deep learning models have been drawing significant attention in the literature of state-of-charge (SOC) estimation because of their capabilities to capture non-trivial temporal patterns. However, most of such models ignore cell-to-cell variations or focus on short-term estimations that are not practical for battery cells with limited charging-discharging history. We propose a Controllable Deep Transfer Learning (CDTL) network for short and long-term SOC estimations at early stages of degradation. The CDTL utilizes shared knowledge between the target cells of interest and historical source cells with rich SOC data using controllable Multiple Domain Adaptation (MDA). Specifically, the CDTL consists of two long-short term memory (LSTM) networks, the source LSTM, and the target LSTM. The source LSTM is trained on SOC data from historical battery cells. The target LSTM is then trained using limited available SOC data from the target cell and the transferred knowledge from the source LSTM using controllable MDA with adaptive regularization. The contributions of the CDTL are two-folded. First, it reduces the likelihood of negative transfer learning using controllable MDA with adaptive regularization, which enhances the target LSTM generalizability for long-term SOC estimation. Second, the CDTL offers theoretical guarantees on the controllability and convergence of transferred knowledge from the source cell to target cell. The experimental results demonstrate that the proposed CDTL outperforms existing deep and transfer learning benchmarks with 1) a maximum improvement of 60% in root-mean-squared error (RMSE) for battery cells with the same chemistry, 2) an average improvement of 50% in RMSE across different battery chemistries, and 3) about 39% reduction in computational time. [ABSTRACT FROM AUTHOR]

Abstract: Recently, several accidents caused by cyber attacks on digital systems have been reported in the nuclear industry. To cope with such threats, regulatory agency and standardization organization have published several guidelines for nuclear power plants. However it is difficult to apply the requirements to research reactor facilities directly because the characteristics in terms of facility scale, purpose, and system design, are different from those of power plants. This paper suggests a graded approach to cyber security in a research reactor facility. It introduces cyber security activities for guarding digital systems of a reactor facility safely as a cyber security program based on the practices at a research reactor facility. [Copyright &y& Elsevier]

Abstract: Endoglin is an accessory receptor molecule that, in association with transforming growth factor β (TGF-β) family receptors Types I and II, binds TGF-β1, TGF-β3, activin A, bone morphogenetic protein (BMP)-2 and BMP-7, regulating TGF-β dependent cellular responses. Relevant to diabetic nephropathy, endoglin, expressed in vascular endothelial and smooth muscle cells, fibroblasts, and mesangial cells, negatively regulates extracellular matrix (ECM). The aim of this study was to evaluate endoglin expression in cultured skin fibroblasts from patients with Type 1 diabetes with and without diabetic nephropathy. Kidney and skin biopsies were performed in 125 Type 1 diabetic patients. The 20 with the fastest rate of mesangial expansion (estimated by electron microscopy) and proteinuria (“fast-track”) and the 20 with the slowest rate and normoalbuminuria (“slow-track”), along with 20 controls were studied. Endoglin mRNA expression was assessed by microarray and quantitative real-time polymerase chain reaction (QRT-PCR) and protein expression by Western blot. Age and sex distribution were similar among groups. Diabetes duration was similar (20±8 vs. 24±7 years), hemoglobin A1c lower (8.4±1.2% vs. 9.4±1.5%), and glomerular filtration rate higher (115±13 vs. 72±20 ml/min per 1.73 m2) in slow-track vs. fast-track patients. Microarray endoglin mRNA expression levels were higher in slow-track (1516.0±349.9) than fast-track (1211.0±274.9; P=.008) patients or controls (1223.1±422.9; P=.018). This was confirmed by QRT-PCR. Endoglin protein expression levels correlated with microarray (r=0.59; P=.044) and QRT-PCR (r=0.61; P=.034) endoglin mRNA expression. These studies are compatible with the hypothesis that slow-track Type 1 diabetic patients, strongly protected from diabetic nephropathy, have distinct cellular behaviors that may be associated with reduced ECM production. [Copyright &y& Elsevier]

Two new heterometallic metal–organic frameworks (MOFs), LnZnTPO 1 and 2, and two homometallic MOFs, LnTPO 3 and 4 (Ln=Eu for 1 and 3, and Tb for 2 and 4; H3TPO=tris(4‐carboxyphenyl)phosphine oxide) were synthesized, and their structures and properties were analyzed. They were prepared by solvothermal reaction of the C3‐symmetric ligand H3TPO with the corresponding metal ion(s) (a mixture of Ln3+ and Zn2+ for 1 and 2, and Ln3+ alone for 3 and 4). Single‐crystal XRD (SXRD) analysis revealed that 1 and 3 are isostructural to 2 and 4, respectively. TGA showed that the framework is thermally stable up to about 400 °C for 1 and 2, and about 450 °C for 3 and 4. PXRD analysis showed their pore‐structure distortions without noticeable framework–structure changes during drying processes. The shapes of gas sorption isotherms for 1 and 3 are almost identical to those for 2 and 4, respectively. Solvothermal immersion of 1 and 2 in Tb3+ and Eu3+ solutions resulted in the framework metal‐ion exchange affording 4 and 3, respectively, as confirmed by photoluminescence (PL), PXRD, IR, inductively coupled plasma atomic emission spectroscopy (ICP‐AES), and energy‐dispersive X‐ray (EDX) analyses. [ABSTRACT FROM AUTHOR]

The utilization of automatic mooring systems is under extensive interest with the growing technological demands for autonomous ships and smart ports. A vacuum suction pad with a rubber seal, which endures external loads to the moored ship, such as mooring forces, is a critical element in an automatic mooring system. To develop a high-performance automatic mooring system, a vacuum suction pad and a rubber seal need to be thoroughly designed, manufactured, and evaluated. This work demonstrates a protocol for evaluating the performance of a vacuum suction pad through both simulation and experimental testing. Uniaxial tensile testing was conducted to understand the mechanical behavior of a rubber seal. Stabilized stress-strain curves were utilized to find an optimal strain energy density function model and to extract material parameters for 3D finite element method (FEM) simulations. The FEM simulations were conducted to calculate strain distributions, contact status and the maximum load capacity, and along with the FEM simulation results, experimental evaluations of the vacuum suction pad were designed and conducted against static and cyclic loads. Based on the simulation and experimental results, we can conclude that the vacuum suction pad can maintain the stable suction at least up to 25 kN suitable for the use in automatic mooring systems. • A protocol is demonstrated to evaluate the performance of a rubber seal and a vacuum suction pad which can withstand a heavy load and thus, can be applicable to an automatic mooring system. • Finite element method (FEM) simulations with material parameters of the rubber seal material extracted from uniaxial tests can be effective to predict the rubber seal performance. • Experimental evaluation of a vacuum suction pad performance against static and cyclic loads to mimic the mooring situations is demonstrated, which support the FEM simulation results. [ABSTRACT FROM AUTHOR]

In the heating, ventilation, and air-conditioning (HVAC) system of electric vehicles (EVs), an electric heater is often used for a reheating process that warms up the chilled evaporator outlet air for thermal comfort before it is supplied to the cabin. The usage of the electric heater can significantly reduce the driving range of an EV. Therefore, optimal control of the HVAC system with consideration of the reheating process becomes essential for an increased driving range. In addition, considering the primary role of cabin climate control, it is desirable to intelligently consider the passengers' thermal comfort in climate control design. In this paper, thermal comfort-conscious eco-climate control (TCC-ECC) based on model predictive control (MPC) is proposed to enhance the energy efficiency of the HVAC operation while ensuring passengers' thermal comfort. The MPC design uses a reduced-order HVAC system model based on an ideal vapor-compression cycle. For the integration of thermal comfort into the MPC, a new approach is proposed to obtain an approximate solution of a predictive mean vote (PMV)-based thermal comfort model, which aims to balance computational efficiency and prediction accuracy. With the proposed TCC-ECC, a parametric study is conducted to analyze the impact of weighting factors on energy consumption and thermal comfort under two different thermal load conditions. Then, the performance of the tuned TCC-ECC is evaluated in comparison with a rule-based (RB) controller and the baseline eco-climate control (ECC) without considering thermal comfort. In the performance evaluation, the proposed TCC-ECC demonstrates that with the inclusion of thermal comfort it performs better in terms of energy efficiency and thermal comfort than manually adjusting a target cabin temperature depending on the environmental thermal load. The energy consumption of the proposed TCC-ECC is 22.5% and 35.24% less than that of the RB controller at an ambient temperature of 24 °C and 35 °C, respectively, and 14.5% and 18.5% less than the baseline ECC at the same conditions, respectively. • Eco friendly climate control in an EV should consider both cooling and reheating. • Reheat process in an EV may consume significant energy. • Approximated solution for a PMV-based modified thermal comfort model. • Better energy efficiency by including thermal comfort in MPC-based climate control. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Saline versus Albumin Fluid Evaluation Study," by Simon Finfer, Neil Boyce and Robyn Norton, published in the May 27, 2004 issue.

A role for extrarenal cells in the regeneration following acute renal failure. Background. Recovery of renal function following acute tubular necrosis (ATN) is dependent on the replacement of necrotic tubular cells with functional tubular epithelium. The source of these new tubular cells is thought to be resident renal tubular cells. The discovery of pluripotent bone marrow-derived stem cells has led to a reexamination of the cellular source and processes involved in the recovery from organ injury. Methods. To test the hypothesis in humans that extrarenal cells participate in the recovery following ATN, we examined the origin of tubular cells in male patients with resolving ATN who had received a kidney transplant from a female donor. Immunohistochmistry of kidney biopsies was performed to identify renal tubular epithelial cells (cytokeratin positive) and leukocytes (CD45 positive). Fluorescent in-situ hybridization was used to detect Y chromosome containing cells with DAPI serving as a nuclear stain. All staining was performed on the same section. Results. The Y chromosome was detected in approximately 40% of tubular cell nuclei in male kidneys (positive control) and in no nuclei of female kidneys (negative control). In male recipients of female kidneys who developed ATN, 1% of tubules contained Y chromosome cells defined by their morphology, positive staining for cytokeratin, and negative staining for CD45. When present, multiple cells in a positive tubule stained for the Y chromosome. No Y chromosome containing tubular cells were seen in similar sex mismatched transplants in male recipients who did not develop ATN, suggesting that recipient derived cells do not routinely repopulate the transplanted kidney. Conclusions. This proof-of-principle clinical observation demonstrates that extrarenal cells can participate in the regenerative response following ATN. These findings provide rationale for the cellular therapy of acute renal failure. [ABSTRACT FROM AUTHOR]

Background: The objective of this study is to investigate the differences in incidence rates of targeted diseases by classification of occupations among construction workers in Korea., Methods: In a subject-based cohort of the Korean Construction Worker's Cohort, we surveyed a total of 1,027 construction workers. As occupational exposure, the classification of occupations was developed using two axes: construction business and job type. To analyze disease incidence, we linked survey data with National Health Insurance Service data. Eleven target disease categories with high prevalence or estimated work-relatedness among construction workers were evaluated in our study. The average incidence rates were calculated as cases per 1,000 person-years (PY)., Results: Injury, poisoning, and certain other consequences of external causes had the highest incidence rate of 344.08 per 1,000 PY, followed by disease of the musculoskeletal system and connective tissue for 208.64 and diseases of the skin and subcutaneous tissue for 197.87 in our cohort. We especially found that chronic obstructive pulmonary disease was more common in construction painters, civil engineering welders, and civil engineering frame mold carpenters, asthma in construction painters, landscape, and construction water proofers, interstitial lung diseases in construction water proofers., Conclusions: This is the first study to systematically classify complex construction occupations in order to analyze occupational diseases in Korean construction workers. There were differences in disease incidences among construction workers based on the classification of occupations. It is necessary to develop customized occupational safety and health policies for high-risk occupations for each disease in the construction industry., Competing Interests: Competing interests: The authors declare that they have no competing interests., (Copyright © 2023 Korean Society of Occupational & Environmental Medicine.)

Background: In the manufacturing industry, work-family conflict (WFC) is related to working hour characteristics. Earlier studies on the relationship between working hour characteristics and WFC in the manufacturing industry have been limited to some regions in Korea. No study has addressed the data on a national scale. Thus, this study investigated the impact of weekly working hours, weekend work, and shift work on WFC using national-scale data., Methods: This study was based on the fifth Korean Working Conditions Survey of 5,432 manufacturers. WFC consists of 5 variables; WFC1 "kept worrying about work"; WFC2 "felt too tired after work"; WFC3 "work prevented time for family"; WFC4 "difficult to concentrate on work"; WFC5 "family responsibilities prevented time for work". As WFC refers to the inter-role conflict between the need for paid work and family work, WFC has been measured in two directions, work to family conflict (WTFC: WFC1, 2, 3) and family to work conflict (FTWC: WFC4, 5). With these WFC variables, we conducted multiple logistic analyses to study how working hours, weekend work, and shift work impact WFC., Results: Korean manufacturers' prolonged working hours increased all aspects of WFCs. Odds ratios (ORs) of WFCs based on working hours (reference of under 40 hours) of 41-52, 53-60, over 61 were 1.247, 1.611, 2.279 (WFC1); 1.111, 2.561, 6.442 (WFC2); 1.219, 3.495, 8.327 (WFC3); 1.076, 2.019, 2.656 (WFC4); and 1.166, 1.592, 1.946 (WFC5), respectively. Shift-work in the WFC2 model showed a significantly higher OR of 1.390. Weekend work 'only on Saturday' had significant ORs with WFC2 (1.323) and WFC3 (1.552)., Conclusions: An increase in working hours leads to the spending of less time attending to problems between work and family, causing both WTFC and FTWC to increase. As weekends, evenings, and nighttime are considered to be family-friendly to people, working on weekends and shift-work were highly correlated to WTFC., Competing Interests: Competing interests: The authors declare that they have no competing interests., (Copyright © 2022 Korean Society of Occupational & Environmental Medicine.)

Background: A job-exposure matrix (JEM) is an important surrogate indicator to evaluate past exposure levels. Although a Korean asbestos JEM has been constructed previously, this JEM includes only a few industrial and occupational groups. This study aimed to reconstruct the JEM by integrating the latest organized data to improve its utility., Methods: We used recent Korean standard industry and occupation codes and extracted 36 articles from a systematic literature review to initiate the reconstruction of the previous Korean asbestos JEM. The resulting data consisted of 141 combinations of industrial and occupational groups. Data from the Netherlands's JEM were also reviewed and categorized into 70 industrial and 117 occupational groups by matching with the Korean data. We also utilized Germany's data, which consisted of 10 industrial and 14 occupational groups., Results: The reconstructed Korean asbestos JEM had 141 combinations of industries and occupations. The time periods are from the 1980s to the 2000s in 10-year intervals. Most of the data were distributed between the 1990s and the 2000s. Occupations with high exposure to asbestos included knitting and weaving machine operators, automobile mechanics or assemblers, ship mechanics or assemblers, mineral ore and stone products processing mechanics, and metal casting machine operators or mold makers., Conclusions: The reconstructed Korean asbestos JEM has expanded the type and duration of the occupational groups of the previous JEM and can serve as an important reference tool for evaluating asbestos exposure and designing compensation and prevention policies in Korea., Competing Interests: All authors have no conflicts of interest to declare., (© 2020 The Authors.)