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Background: Sepsis is the most common cause of death in hospitals, and intra-abdominal infection (IAI) accounts for a large portion of the causes of sepsis. We investigated the clinical outcomes and factors influencing mortality of patients with sepsis due to IAI. Methods: This post-hoc analysis of a prospective cohort study included 2126 patients with sepsis who visited 16 tertiary care hospitals in Korea (September 2019–February 2020). The analysis included 219 patients aged > 19 years who were admitted to intensive care units owing to sepsis caused by IAI. Results: The incidence of septic shock was 47% and was significantly higher in the non-survivor group (58.7% vs 42.3%, p = 0.028). The overall 28-day mortality was 28.8%. In multivariable logistic regression, after adjusting for age, sex, Charlson Comorbidity Index, and lactic acid, only coagulation dysfunction (odds ratio: 2.78 [1.47–5.23], p = 0.001) was independently associated, and after adjusting for each risk factor, only simplified acute physiology score III (SAPS 3) (p < 0.001) and continuous renal replacement therapy (CRRT) (p < 0.001) were independently associated with higher 28-day mortality. Conclusions: The SAPS 3 score and acute kidney injury with CRRT were independently associated with increased 28-day mortality. Additional support may be needed in patients with coagulopathy than in those with other organ dysfunctions due to IAI because patients with coagulopathy had worse prognosis. [ABSTRACT FROM AUTHOR]

The Korean government implemented a 52-h workweek policy for employees' welfare. Consequently, companies face workforce availability reduction with the same number of employees. That is, labor-dependent companies suffer from workforce shortage. To handle the workforce shortage, they increase irregular employees who are paid relatively less. However, the problem of 'no-show', due to the stochastic characteristics of irregular employee's absence, happens. Therefore, this study aims to propose a staff scheduling strategy considering irregular employee absence and a new labor policy by using linear programming. By deriving a deterministic staff schedule through system parameters derived from the features and rules of an actual company in the numerical experiment, the practicality and applicability of the developed mathematical model are proven. Furthermore, through sensitivity analysis and simulation considering the stochastic characteristics of absences, various proactive cases are provided. Through the proactive cases, the influence of the change of the average percent of irregular employees' absences on the total labor costs and staff schedules and the expected number who would not come to work could be given when assuming the application in practice. This finding can help decision-makers prepare precautious measures, such as assigning extra employees in case of an irregular employee's absence. [ABSTRACT FROM AUTHOR]

This study aims to investigate the difference in physiological loading on the spine in three different motions (flexion–extension, lateral bending, and axial rotation) between osteoporotic and normal spines, using finite element modelling. A three-dimensional finite element (FE) model centered on the lumbar spine was constructed. We applied two different material properties of osteoporotic and normal spines. For the FE analysis, three loading conditions (flexion–extension, lateral bending, and axial rotation) were applied. The von Mises stress was higher on the nucleus pulposus at all vertebral levels in all movements, in the osteoporosis group than in the normal group. On the annulus fibrosus, the von Mises stress increased at the level of L3–L4, L4–L5, and L5–S in the flexion–extension group and at L4–L5 and L5–S levels in the lateral bending group. The values of two motions, flexion–extension and lateral bending, increased in the L4 and L5 cortical bones. In axial rotation, the von Mises stress increased at the level of L5 of cortical bone. Additionally, the von Mises stress increased in the lower endplate of L5–S and L4–L5 in all movements, especially lateral bending. Even in the group with no increase, there was a part that received increased von Mises stress locally for each element in the three-dimensional reconstructed view of the pressure distribution in color. The von Mises stress on the lumbar region in the three loading conditions, was greater in most components of osteoporotic vertebrae than in normal vertebrae and the value was highest in the nucleus pulposus. Considering the increase in the measured von Mises stress and the local increase in the pressure distribution, we believe that these results can contribute to explaining discogenic pain and degeneration. [ABSTRACT FROM AUTHOR]

Background: The treatment options for basal ganglia intracerebral hemorrhage (ICH), either surgical or conservative, remain controversial. A previous study developed "A new modified ICH (MICH) score" that suggests which treatment option will be better for basal ganglia ICH. According to this scoring system, a MICH score of 0 or 1 indicates that conservative treatment is better than surgical treatment. The purpose of this study was to determine whether conservative treatment is still a better option for a basal ganglia hemorrhage in patients with MICH scores of 0 and 1, with initial poor motor grades. Methods: This retrospective study was comprised of 41 patients with a spontaneous basal ganglia hemorrhage. These patient groups had no previous brain lesions, their initial MICH score was 0 or 1, and the manual muscle test (MMT) of their hand was grade 2+ or lower in the initial evaluation. All patients were transferred to the Department of Rehabilitation Medicine and received rehabilitation treatment. Ten patients had an operative intervention, which was burr-hole aspiration or craniotomy with hematoma removal. The control group included 31 patients who underwent conservative treatment. Outcome evaluations used the Berg Balance Scale (BBS), Modified Barthel Index (MBI), and Brunnstrom recovery stage (BRS) which were evaluated at initial and regular follow-ups after 1, 3, and 6 months. We defined an improvement state if the BRS of their hand became 4 or more in 6 months, which means an escape from the synergic pattern. Results: Demographic characteristics showed no significant differences in age, sex, hemiplegic side, initial GCS score, presence of IVH and hydrocephalus, or distribution of MICH scores 0 and 1. There was only a significant difference in the distribution of hematoma volume between groups of less than 20 mL and groups from 21 to 50 mL (p = 0.049). There were no significant differences in MBI values in 1 month or improvement of BRS of their hand in 6 months between the two groups. Conclusions: Even in the group classified as predominantly conservative in basal ganglia hemorrhage patients, if the initial muscle strength is low, it is necessary to reconsider whether conservative treatment is superior to surgical treatment in terms of functional improvement. [ABSTRACT FROM AUTHOR]

Trigeminal neuralgia (TN) is a debilitating condition characterized by sudden, excruciating facial pain due to neurovascular compression of the trigeminal nerve. Stent deployment can change the course of the superior cerebellar artery upwards, possibly releasing the root entry zone of the trigeminal nerve. We developed a novel stent, the Transform stent, for TN treatment, and evaluated its mechanical properties using benchtop and in vitro hemocompatibility tests. We compared the performance of Transform and Enterprise stents in treating TN because they share similar self-expanding closed-cell features in the manufacturing process, are derived from nitinol tubes, and are fabricated through a laser-cutting process, but also because only the safety of Enterprise stents deployed in intracranial arteries has been reported clinically. All benchtop measurements, including radial force, trackability, bending stiffness, and conformability, were performed thrice for each stent model, and their average values are presented. Transform stents showed higher radial forces in vessels of diameters ranging from 1.0 mm than Enterprise stents. The trackability of the Transform stent was better than that of the Enterprise stent in a neurovascular model. Bending stiffness was stronger in the Transform stent whereas conformability was superior in the Enterprise stent. No significant thrombogenic issues were observed in the in vitro hemocompatibility tests. This study demonstrated the Transform stent as a potential option and paved the way for innovative endovascular approaches for the future TN treatment. Namely, the study confirmed that the characteristics of Transform stents at benchtop and in vitro evaluations may be used as a first step for studies such as in vivo pre- and clinical studies. [ABSTRACT FROM AUTHOR]

Delayed hemothorax after thoracic trauma is a rare type of thoracic injury that may require angioembolization and surgical treatment. We report a case of a 59-year-old man with a delayed massive hemothorax from a fall-induced blunt thoracic trauma, causing multiple right lower rib fractures. The patient fell from a chair while standing on and working from it. He was diagnosed with right 7th–11th rib fractures, scanty hemothorax and liver contusion. The patient was hospitalized and received conservative treatment, and a delayed massive hemothorax was present on the fourth day after the injury. Chest tube drainage and video-assisted thoracoscopic surgery were performed, and the patient was discharged 16 days after the surgery without bleeding or other complications. Delayed hemothorax should be considered when thoracic trauma patients complain of chest discomfort, dyspnea, cold sweating or fatigue. Early recognition, appropriate diagnosis and rapid intervention can improve prognosis and lead to successful patient treatment. [ABSTRACT FROM AUTHOR]

Summary: In the present report, the fatty acid alkyl esters and fatty acid amides were synthesized from natural triglycerides by highly selective solvent‐free one‐step methods using 3.5‐CaO@KC‐400 nanocrystals as a heterogeneous catalyst. A modified wetness chemical impregnation method was used to prepared potassium carbonate‐doped CaO, ZnO, and MgO nanocrystals. The prepared 3.5‐CaO@KC‐400 nanocrystals were found as the most efficient heterogeneous catalyst (5%, w/w) for amidation (6:1 M ratio of diethanolamine/oil, 110°C) and transesterification (12:1 M ratio of methanol/oil, 65°C) of waste cooking oil and took 30 minutes for the completion of both the reactions. The 3.5‐CaO@KC‐400 nanocrystals were found to be efficient at room temperature also and reused for 10 reaction cycles for both reactions. The pseudo‐first‐order kinetic model was applied and the first‐order rate constant was calculated as 0.15 minute−1 and 0.103 minute−1 for the amidation and transesterification reactions of waste cooking oil, respectively. [ABSTRACT FROM AUTHOR]

Highlights • Aminolyzed PLLA microcylinders were introduced to a GelMA-based bioink for a better printing experience. • The printed microcylinder-laden bioink proved to have higher resolution than pure GelMA ink. • The pre-osteoblasts printed with the novel bioink exhibited increased viability compared to the conventional bioink. Abstract Developing bioinks for 3D bioprinting that are easy to print and highly biocompatible is essential for the growth of the tissue engineering field. Here, a gelatin methacryloyl-based (GelMA) bioink that is loaded with aminolyzed poly(L-lactic acid) (PLLA) microcylinders is developed. The bioink showed better printing capabilities compared to pure GelMA, which exhibited a smaller window of high quality printability. The addition of microcylinders makes the bioink more forgiving to print by increasing its minimum viscosity while keeping its structural integrity after printing. Cell viability of printed constructs was compared to non-printed constructs to see the effects of shear stress in the new bioink. [ABSTRACT FROM AUTHOR]

A bimodal grain structure consisting of fine grains ( d ~ 1–2 µm) and coarse grains ( d ~ 10–20 µm) was achieved in the biomedical Co–20Cr–15W–10Ni alloy via medium cold rolling (area reduction of 50%) followed by short-term annealing (15 min) at relatively low temperatures (950–1100 °C). The medium cold rolling induced a heterogeneous microstructure featuring the coexistence of severely deformed regions and weakly deformed domains. With short-term annealing at low temperatures, fine and coarse grains were preferentially recrystallized in severely deformed regions and weakly deformed domains, respectively, resulting a bimodal grain size distribution. During tension, dislocations were more rapidly generated in the fine grains, thus increasing the strain hardening, while they glided longer on the {111} planes in the coarse grains, contributing a high ductility. The combination of these two factors provided well-balanced strength–ductility behavior with an ultimate tensile strength of 1278 MPa, a yield strength of 787 MPa, and an elongation to fracture of 53%, making the alloy suitable for surgical implant and stent applications where the strength and ductility are both important to ensure mechanical reliability in a human body. [ABSTRACT FROM AUTHOR]

The study aims to evaluate the method of Thermal Response Tests (TRTs) in assessing in-situ residual saturation of CO 2 storage in saline aquifers. Similar to TRTs, mathematically the same type of an exact analytical solution presented by Theis is well-established for the transient drawdown in an infinite uniform confined aquifer. With the change of supercritical CO 2 and saline water in pore space, the inverse models of temperature change over time either heating or cooling may lead to the detection of a change in thermal properties of fluids and sold matrix. In assessing the overall thermal conductivity using the three inverse models, the Wang model describes the saline aquifer of the interest structurally well among the chosen four conductivity models. The results of the Wang model and the arithmetic model showed almost insensitivity to the residual CO 2 saturation up to 50 percents in the estimation of the overall thermal conductivity, while they did a sensitivity to porosity variation of the same range. Accuracy analysis of the three inversion models showed that a developed nonlinear least square inverse model produces the least error in the estimation consistently with the wide range of the residual saturation variation of CO 2 . [ABSTRACT FROM AUTHOR]

Herein, nitrogen-doped tin oxide intercalated activated carbon nanocomposite (N-AC/SnO 2 ) were prepared using hydrothermal strategy and explored as an electrode for capacitive desalination and disinfection. Although tin oxide (SnO 2 ) has good characteristics, the nitrogen must be carefully considered for modifying the characteristics of the carbonaceous materials to improve the performance as an electrode in the CDI process. The characterization of the proposed materials which investigated by XRD, TEM, FE-SEM, XPS and FT-IR affirmed the formation of the nanocomposite. The electrosorption behavior investigated by electrochemical techniques demonstrates that, compared to the specific capacitance of the AC and AC/SnO 2 (207.46 F g −1 and 233.21 F g −1 ), that of the N-AC/SnO 2 is higher at 408.8 F g −1 , and N-AC/SnO 2 exhibits better electrical conductivity. The CDI performance evaluated by batch mode experiments through an applied voltage of 1.2 V in a 50 mg L −1 NaCl aqueous solution shows that the N-AC/SnO 2 electrode introduces a higher electrosorptive capacity of 3.42 mg g −1 , an enhanced desalination efficiency of 61.13%, and good antibacterial performance. Overall, the present study demonstrates that N-AC/SnO 2 has considerable potential as an electrode material for CDI application. [ABSTRACT FROM AUTHOR]

The tensile test criterion to obtain a reliable stress-strain curve from load-displacement data of metallic materials exhibiting twinning or phase transformation was developed especially for environments that do not allow the use of an extensometer. The study shows that neither ASTM E8 / E8M standard specimen nor strip-shaped specimen geometry was appropriate for converting load-displacement data to an actual stress-strain curve; the former exhibited an undesired two-stage yield, while the latter revealed premature fracture. To solve these problems, the relationship between the specimen geometries and load-displacement data was carefully analyzed for dog-bone type specimens having a minimized fillet radius; it was found that the ratio of grip width W gr to gauge width W ga should be higher than the ratio of fracture stress to the first yield stress σ 1 . Otherwise, a second yield always occurred when the stress reached a value close to σ 1 W gr / W ga , obstructing the data analysis to reconstruct the actual stress-strain curve from load-displacement data. Finally, a methodology to verify whether the tensile test satisfied the criterion was suggested in terms of a nominal strain hardening rate. [ABSTRACT FROM AUTHOR]

The effect of the solution treatment and aging (STA) conditions on the tensile properties of Ti–4 mass%Fe–4 mass%Al–0.25 mass%Si alloy has been investigated in this work. The obtained results revealed that varying the solution temperature affected the stability of the β phase due to the Fe partitioning (which inhibited the β→α′/α″ reaction during water quenching), while the magnitude of the aging temperature determined the predominant products of the β→isothermal ω→secondary α rich →secondary α lean +TiFe phase transformation with distinct tensile characteristics. In addition, the relationship between the alloy microstructure and its tensile properties was discussed. [ABSTRACT FROM AUTHOR]

Microstructure, mechanical properties as well as phase transformation behavior of newly developed Ni 49 Ti 36 Hf 15-x Ta (x=0, 3, 6, 9, 12) high temperature shape memory alloys has been investigated. Ni 49 Ti 36 Hf 15 alloy consists of (Ti,Hf) 2 Ni phase which is brittle and incoherent with the martensite matrix. However, addition of Ta in place of Hf suppresses the brittle (Ti,Hf) 2 Ni phase formation with white Ta rich phase. More than 70% reduction in area has been observed in Ta added Ni 49 Ti 36 Hf 15 high temperature shape memory alloys. The austenitic transformation temperature is well above 200 °C (473 K) for lower Ta concentrations with up to 6 at. %; however; at higher Ta concentrations (i.e. above 9 at. %) decreases significantly. Overall, the addition of Ta greatly influences the hot deformation behavior and high temperature shape memory properties of Ni 49 Ti 36 Hf 15 alloy. The present paper discusses the detailed investigation on Ni 49 Ti 36 Hf 15-x Ta (x=0, 3, 6, 9, 12) high temperature shape memory alloys. [ABSTRACT FROM AUTHOR]

The mechanisms of dynamic recrystallization (DRX) in a 50Ti-47Ni-3Fe alloy are studied using compression tests at temperatures of 1023–1323 K with strain rates of 0.01–10 s −1 , and the resulting stress-strain curves are used to construct an Arrhenius equation with a Zener-Hollomon parameter (Z). The relationship between this Z parameter and stress, and its effect on the subgrain size are discussed. With the help of electron backscatter diffraction (EBSD), the development of recrystallizing grain boundaries is tracked in deformed grains with different grain orientation spread (GOS) values. Continuous dynamic recrystallization (CDRX) is subsequently confirmed by evidence of the conversion of low-angle boundaries (LAGBs) into high-angle boundaries (HAGBs). Grain boundary sliding (GBS) and HAGB migration are therefore considered secondary mechanisms under high-Z (ln Z > 29) and low-Z (ln Z < 23.5) conditions, but CDRX is confirmed as the dominant DRX mechanism. [ABSTRACT FROM AUTHOR]

This study develops and characterizes a fiber-optic monitoring system for the key environment variables of the spent nuclear fuel pool (SNFP) at a nuclear power plant. The three key environmental variables indicating the SNFP status directly are its water temperature, water level, and radiation level. First, this study develops and characterizes the individual fiber-optic sensors for measuring the three key environmental variables and then assembles them into an integrated monitoring system. The individual fiber-optic sensors commonly use optical fibers to transmit the signals delivered from their sensing probes despite their different characteristics. For the fiber-optic temperature sensor (FOTS), two types of FOTS are developed: contact and non-contact types, which are distinguished by whether their sensing probes are in direct contact with water. The contact-type FOTS uses a copper metal cap as its sensing probe, and the non-contact-type FOTS uses an infrared optical fiber, whose peripheral surface is coated with an anti-fog solution as its sensing probe. The fiber-optic water level sensor (FOWS) consists of optical fibers with their ends connected to the sensing probes fabricated with a NaCl solution and stainless steel. The FOWS measures the water level using the Fresnel reflection phenomenon, i.e., reflection of a portion of incident light at a discrete interface between two media having different refractive indices. The FOWS identifies the water level by measuring the amount of light reflected at the interface between the sensing probe and its outside medium, which varies according to whether the sensing probe is in contact with water. The fiber-optic radiation sensor (FORS) measures the gamma radiation in the SNFP. The sensing probe of FORS is a cylindrical-shaped LYSO:Ce scintillator, whose peripheral is wrapped with aluminum foil as the reflector. After characterizing the three individual sensors developed in this study, they are assembled and tested at a model water pool, 500 mm × 500 mm × 500 mm in size. The performance test results shows that individual sensors can measure the changes in each environmental variable in real-time. [ABSTRACT FROM AUTHOR]

B Introduction: b Sepsis is the most common cause of death in hospitals, a large proportion of which may be attributed to intra-abdominal infection (IAI). B Conclusions: b Considering the independent risk factors affecting 28-day mortality, more intensive care may be needed in patients with coagulopathy than in those with other organ dysfunction due to IAI. [Extracted from the article]

• Instantaneous current residual map (ICRM) is proposed for CNN-based fault diagnosis. • ICRM highlights fault-related physical behaviors of stator motor current signals. • A motor fault type can be figured out by using ICRM as the 2D input to a CNN model. • The effectiveness of ICRM for fault diagnosis of a PMSM is experimentally validated. To take full advantage of a convolutional neural network (CNN) for deep learning-based fault diagnosis, many studies have examined the transformation of sensory signals into a two-dimensional (2D) input image. An important question to consider is: how can fault-related signatures in motor stator current signals be incorporated into the 2D input image to a CNN model for fault diagnosis of a permanent magnet synchronous motor (PMSM)? To answer the question, this study newly proposes a novel health image, namely instantaneous current residual map (ICRM). Inspired by the idea that the phase and amplitude modulations in motor stator current signals are related to faulty states of a PMSM, the overall procedure for constructing ICRM includes two key steps: (1) to calculate current residuals (CRs); and (2) to spread the scaled CR pairs into a 2D matrix. A type of faults can be figured out by analyzing a degree or shape of spreading of the CRs in ICRM. Moreover, ICRM is robust to variable operating conditions in practical settings because the scaled CRs that the effects of the operating conditions are reduced can highlight fault-induced irregularities. To demonstrate the effectiveness of ICRM, it was experimentally validated using a surface mounted PMSM, operated under variable-speed and different load torque conditions. [ABSTRACT FROM AUTHOR]

Introduction: With the availability of retrospective pharmacovigilance data, the common data model (CDM) has been identified as an efficient approach towards anonymized multicenter analysis; however, the establishment of a suitable model for individual medical systems and applications supporting their analysis is a challenge. Objective: The aim of this study was to construct a specialized Korean CDM (K-CDM) for pharmacovigilance systems based on a clinical scenario to detect adverse drug reactions (ADRs). Methods: De-identified patient records (n = 5,402,129) from 13 institutions were converted to the K-CDM. From 2005 to 2017, 37,698,535 visits, 39,910,849 conditions, 259,594,727 drug exposures, and 30,176,929 procedures were recorded. The K-CDM, which comprises three layers, is compatible with existing models and is potentially adaptable to extended clinical research. Local codes for electronic medical records (EMRs), including diagnosis, drug prescriptions, and procedures, were mapped using standard vocabulary. Distributed queries based on clinical scenarios were developed and applied to K-CDM through decentralized or distributed networks. Results: Meta-analysis of drug relative risk ratios from ten institutions revealed that non-steroidal anti-inflammatory drugs (NSAIDs) increased the risk of gastrointestinal hemorrhage by twofold compared with aspirin, and non-vitamin K anticoagulants decreased cerebrovascular bleeding risk by 0.18-fold compared with warfarin. Conclusion: These results are similar to those from previous studies and are conducive for new research, thereby demonstrating the feasibility of K-CDM for pharmacovigilance. However, the low quality of original EMR data, incomplete mapping, and heterogeneity between institutions reduced the validity of the analysis, thus necessitating continuous calibration among researchers, clinicians, and the government. [ABSTRACT FROM AUTHOR]

A tissue engineering composite scaffold serves as a temporary skeleton to accommodate and stimulate new tissue growth. Here we report the development of a biodegradable porous composite scaffold made from the bioactive chitosan (CHN) and hyaluronic acid (HYA) with graphene oxide (GO). The CHN–HYA–GO composite scaffold was successfully prepared and compared with CHN-HYA composite scaffold and found that CHN–HYA–GO significantly improved mechanical and biological properties. Moreover, the CHN–HYA–GO composite scaffold possessed an adequate porosity, swelling behavior and degradation rate to mimic the extracellular matrix (ECM) with a favorable cell attachment and proliferation. The cells in contact with CHN–HYA–GO composite scaffolds remained viable and exhibited a high growth potential. Therefore the uniquely fabricated CHN–HYA–GO composite scaffolds possess great potential for various tissue engineering applications. [ABSTRACT FROM AUTHOR]

Bulk nanocrystalline ( d = 20–40 nm) Ni–Ti shape memory alloy was produced via cold marforming, followed by optimum post-heat treatment. The total accumulative strain ( ε ∼ 0.7) during the process was much lower than that typically imposed during severe plastic deformation operations (i.e., 5 ≤ ε ≤ 12). In-situ heating transmission electron microscopy revealed that the present process was effective in promoting static recrystallization and limiting grain growth. The nanocrystalline alloy exhibited enhanced shape memory behaviors. [ABSTRACT FROM AUTHOR]

Plastic anisotropy and associated deformation mechanisms of rolling textured high purity alpha phase titanium were investigated by carrying out uniaxial compression tests along the three featured directions, the rolling direction (RD), normal direction (ND) and transverse direction (TD), in combination with an electron backscatter diffraction measurement and a Schmid factor (SF) analysis. The results revealed that the specific crystallographic feature of the material, caused by rolling texture, influences the activities of dislocation slips and twinning by affecting their SF, and this significantly varies with the loading direction, consequently leading to anisotropic deformation. The material yielding was dominated by dislocation slips, and the change of yielding mechanism with the loading direction (prismatic slip for the RD and TD, and basal slip for the ND) gave rise to yielding anisotropy. As the material deformed beyond the yielding point, deformation twins took place and played a decisive role in the deformation. The twinning characteristics including types of twins, morphology, twin area fraction with strain and related texture modification significantly varied with the loading direction, and this had a completely different effect on strain hardening behavior, thereby causing deformation anisotropy. [ABSTRACT FROM AUTHOR]

An analytical model is developed to evaluate airtightness, which is one of the most important requirements of vacuum tube transportation systems. The main objective of the model is to anticipate the pressure inside a closed structure, which initially decreases and then rises with time owing to the inflow of the air outside. The model is formulated by using Darcy’s law and by solving the differential equations that consider the air permeability of the material and physical configuration of the tube. Equations are derived for a tube section in two cases: one with constant thickness and another with variable thickness. Although the developed model must be verified experimentally, results simulated by using the model with several assumed sections were consistent with the findings of a previous study. The mathematical model developed here to predict the behavior of the pressure inside a vacuum tube structure could be effectively used to evaluate the airtightness of vacuum tube transportation systems. Such data could provide background technical information for the practical design of the system. [ABSTRACT FROM AUTHOR]

We developed a geothermal monitoring system with an open-source Internet of Things (IoT) system. The study's objective is to achieve an economical alternative solution to the expensive commercial data loggers, local PC-based control, data storage limitation, the number of sensor connections, and secure data transmission over the Internet in a decentralized renewable energy system. The developed system consists of hardware and software customized with open-source support that helps resolve the conventional limitations that the commercial system inherently has. We have applied the system to a geothermal energy system deployed at a residential care facility for the elderly in Chuncheon, South Korea. The proposed system enabled us to acquire the data of temperature and fluid flow in real-time and for a prolonged period (i.e., years) at an affordable price compared to installing a conventional data-acquisition system. The real-time multi-year-long data helped confirm seasonality in heating and cooling. We can also apply the same proposed system to the other renewable energy systems monitoring temperature, pressure, wind speed, displacement, noise, seismicity, etc. • Development of a geothermal monitoring system with an open-source IoT system. • The system was applied to a geothermal system deployed at a residential care facility. • The real-time multi-year-long data helped confirm seasonality in heating and cooling. • We can also apply the same proposed system to the other renewable energy. [ABSTRACT FROM AUTHOR]

Functional graded nanobiomembranes (FGMs) with multiple layers were created by a single process using a novel electrospinning system equipped with a generator and a PCI type motion board as a controller in order to control the drug release rate. By varying physical apparatus-related parameters such as nozzle-to-collector distance via a robot and the collector moving velocity the FGMs were formed. For the membrane base layer, poly-(ε-caprolactone) (PCL) with paclitaxel (PTX) was dissolved in a solvent (dichloromethane, N,N-dimethylformamide) and electrospun. For the top layers, the PCL solution was electrospun according to the distance and FGM system parameters, which can move the collector location at a constant ratio. It was observed that pore size, porosity, and permeability were higher when the membrane was spun at the far distance. The top surface of FGM is more porous, rougher, more permeable, and more hydrophilic so as to be active to the surrounding tissue cells. Meanwhile, the porous inside membrane was as low as the membrane spun at a close distance. Thus it induced a slow drug release due to the internal structure of FGM, which is considered to be very effective for slow drug release as well as bioactivity and bioconductivity. [ABSTRACT FROM AUTHOR]

Feature selection based on an ensemble classifier has been recognized as a crucial technique for modeling high-dimensional data. Feature selection based on the random forests model, which is constructed by aggregating multiple decision tree classifiers, has been widely used. However, a lack of stability and balance in decision trees decreases the robustness of random forests. This limitation motivated us to propose a feature selection method based on newly designed nearest-neighbor ensemble classifiers. The proposed method finds significant features by using an iterative procedure. We performed experiments with 20 datasets of microarray gene expressions to examine the property of the proposed method and compared it with random forests. The results demonstrated the effectiveness and robustness of the proposed method, especially when the number of features exceeds the number of observations. [ABSTRACT FROM AUTHOR]

This study developed a noncontact fiber-optic temperature sensor that can be installed in a spent nuclear fuel pool. This fiber-optic temperature sensor was fabricated using an infrared optical fiber to transmit the infrared light emitted from water at a certain temperature. To minimize the decrease in the detection efficiency of the fiber-optic temperature sensor due to vapor generation, its surface was coated by spraying an antifog solution and drying several times. The measurement data of the fiber-optic temperature sensor was almost linear in the range of 30~70°C. This sensor could be used as an auxiliary temperature monitoring system in a spent nuclear fuel pool. [ABSTRACT FROM AUTHOR]

In this paper, we investigated the effect of laser polishing at different treatment times on the surface roughness and corrosion resistance of a biliary nickel-titanium (NiTi or Nitinol) stent. A specific area of the stent wire surface was checked for changes in roughness by scanning electron microscopy (SEM) and a noncontact profilometer. The corrosion resistance was assessed by potentiodynamic polarization test and electrochemical impedance spectroscopy. The surface characterization revealed that laser polishing reduced the surface roughness of stent by 34-64% compared to that of the as-received stent surface condition depending on the treatment time (i.e., 700-1600 μm). Measurements using potentiodynamic polarization in simulated body fluid solution showed better anti-corrosion performance of laser-polished stent compared to magnetically-polished stent and has comparable corrosion resistance with the as-received stent condition. In this paper, we have shown a preliminary study on the potential of laser polishing for the improvement of surface roughness of stent without affecting much its corrosion resistance. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the effects of particle size and other injection factors on the skin penetration of nanoparticles delivered with a needle-free injector. Experimental and simulation tests were carried out at various parameters. In addition to testing different sizes of nanoparticles, we also observed the effects of several injection pressures and syringe orifice diameters (SOD) on the dispersion pattern of the nanoparticles after injection. Our results showed that as the nanoparticle size increased from 45 nm to 452 nm, the resulting puncture opening, channel diameter, and depth of the nanoparticle dispersion decreased, but the width of the dispersion increased. Conversely, as the SOD increased, the puncture opening, channel diameter, and depth of the dispersion increased, but width of the dispersion decreased. Increasing the injection pressure also decreased the size, depth, and width of the puncture opening. These results identify how these three parameters affect nanoparticle delivery from a needle-free injector; therefore, our findings will be beneficial for optimization and further study of needle-free injectors as a mechanism for transdermal delivery of nanoparticles. [ABSTRACT FROM AUTHOR]

Highlights: [•] We have investigated the effect of cold working on the martensitic transformation. [•] The TiNi wire showed multiple-stage martensitic transformation behavior. [•] The multiple-stage transformations originated from microstructural instability. [ABSTRACT FROM AUTHOR]

Abstract: Beta-TCP (β-TCP) particle-containing LA/PCL micro/nanofibers were fabricated via a one-step electrospinning process. The morphology and chemical structure of the composite nanofibers were characterized by FESEM, XRD, and FTIR. Rougher surfaces were observed for the LA/PCL micro/nanofibers containing β-TCP compared to the neat LA/PCL fibers, which could possibly provide extra sites for cell binding. XRD and FTIR confirmed the presence of β-TCP as being firmly deposited on the fibers. After an immersion in distilled water, we observed that the β-TCP-containing composite fibers were more degradable with many damaged and broken fibers compared to the LA/PCL fibers. MTT assay and immersion test showed better cell viability and proliferation, and improved mineralization ability compared to the LA/PCL only mat. Thus, the incorporation of β-TCP and the presence of LA in PCL micro/nanofibers could result to an improved biocompatibility and faster degradation of the composite fibers, which would possibly be useful for tissue scaffold application. [Copyright &y& Elsevier]

Highlights: [•] Low temperature milling effectively decreased grain size. [•] Low temperature milling was very effective in oxide particle size reduction. [•] Homogeneous distribution of Y2O3 was very important for fine microstructure. [•] Tensile strength was significantly increased by low temperature milling. [Copyright &y& Elsevier]

Highlights: [•] Flow softening of Ti–6Al–4V with a lamellar microstructure was modeled. [•] Flow softening originated from colony rotation and alpha particle coarsening. [•] The model provided an accurate prediction of the flow response during hot working. [ABSTRACT FROM AUTHOR]

Abstract: This study reports on the effect of high-frequency magnetic field on the heating of electrospun polyurethane (PU) nanofibers decorated with Fe2O3 nanoparticles (NPs). The morphological and thermal properties were checked by several characterization techniques. Here, the effect of Fe2O3 NP concentration and intensity of magnetic field on the inductive heating of the composite mat were investigated. Fe2O3 nanoparticles were confirmed to be embedded on/in the nanofibers and their presence has increased the thermal stability of the composite nanofibers compared to the neat PU nanofibers. The composite nanofibers under high-frequency magnetic field showed a temperature increase of 3–17% with respect to the neat PU nanofibers depending on the Fe2O3 NP concentration and magnetic field strength. The present results suggest the potential use of electrospun nanofibers as good substrate for magnetic nanoparticles, and when exposed to external magnetic field, can induce heating that may be useful for localized hyperthermia application. [Copyright &y& Elsevier]

Abstract: The aim of this study was to survey the radon concentrations at 21 elementary schools in Gyeongju, Republic of Korea, to identify those schools with high radon concentrations. Considering their geological characteristics and the preliminary survey results, three schools were finally placed under close scrutiny. For these three schools, continuous measurements over 48h were taken at the principal's and administration office. The radon concentrations at one school, Naenam, exceeded the action level (148Bq/m3) established by the U.S. EPA, while those at the other two schools were below that level. [Copyright &y& Elsevier]

In this paper, we report an evaluation of the performance of a new stent durability tester based on the electrical potential sensing method through accelerated in vitro testing of six different nonvascular Nitinol stents simulating physiological conditions. The stents were subjected to a pulsatile loading of 33 Hz for a total of 62,726,400 cycles, at constant temperature and pressure of 35±0.5 °C and 120±4 mmHg, respectively. The electrical potential of each stent was measured in real-time and monitored for any changes in readings. After conducting test-to-fracture tests, the stents were visually checked, and by scanning electron microscopy. A sudden electrical potential drop in the readings suggests a fracture has occurred, and the only two instances of fracture in our present results were correctly determined by our present device, with the fractures confirmed visually after the test. The excellent performance of our new method shows good potential for a highly reliable and applicable in vitro durability testing for different kinds and sizes of metallic stents. [ABSTRACT FROM AUTHOR]

In law, inferences of causation are sometimes made through a structured process in which multiple participants play various roles, and make decisions concerning various logical components of the overall inference (such as legal rules, policy objectives, presumptions, evidence, burdens of proof and findings of fact). This article illustrates such a process using empirical research into compensation decisions in the USA for injuries allegedly caused by vaccinations. Empirical research into actual legal processes is essential, in order to discover how various players approach their sub-tasks of decisionmaking. It also provides insights for areas outside of law, such as non-monotonic logic, cognitive science, sociology and artificial intelligence. [ABSTRACT FROM AUTHOR]

The type I interferons (IFN-Is) are critical not only in early viral control but also in prolonged T-cell immune responses. However, chronic viral infections such as those of human immunodeficiency virus (HIV) and hepatitis C virus (HCV) in humans and lymphocytic choriomeningitis virus (LCMV) in mice overcome this early IFN-I barrier and induce viral persistence and exhaustion of T-cell function. Although various T-cell-intrinsic and -extrinsic factors are known to contribute to induction of chronic conditions, the roles of IFN-I negative regulators in chronic viral infections have been largely unexplored. Herein, we explored whether 2′–5′ oligoadenylate synthetase-like 1 (OASL1), a recently defined IFN-I negative regulator, plays a key role in the virus-specific T-cell response and viral defense against chronic LCMV. To this end, we infected Oasl1 knockout and wild-type mice with LCMV CL-13 (a chronic virus) and monitored T-cell responses, serum cytokine levels, and viral titers. LCMV CL-13-infected Oasl1 KO mice displayed a sustained level of serum IFN-I, which was primarily produced by splenic plasmacytoid dendritic cells, during the very early phase of infection (2–3 days post-infection). Oasl1 deficiency also led to the accelerated elimination of viremia and induction of a functional antiviral CD8 T-cell response, which critically depended on IFN-I receptor signaling. Together, these results demonstrate that OASL1-mediated negative regulation of IFN-I production at an early phase of infection permits viral persistence and suppresses T-cell function, suggesting that IFN-I negative regulators, including OASL1, could be exciting new targets for preventing chronic viral infection. [ABSTRACT FROM AUTHOR]

The formation of submicrocrystalline (SMC) Ti–6Al–4V was achieved by imposing a much lower strain (ε =1.4) compared to that typically imposed during severe plastic deformation operations (i.e. 4⩽ ε ⩽8). Electron backscatter diffraction analysis revealed that the novel process was effective in promoting dynamic recrystallization and limiting α grain growth. The SMC sheet had much higher yield strength than usual (1134MPa) and reasonable elongation (∼12%) at room temperature, and exhibited enhanced ductility at elevated temperatures. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a simple and efficient strategy was developed for preparing flower-shaped ZnO doped reduced graphene oxide (RGO) composite material by simultaneous crystal growth (of ZnO) and reduction (of graphene oxide) using hydrothermal process. Several analytical techniques, including scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), FT-IR spectroscopy, Raman spectroscopy, and photoluminescence spectroscopy have been used to characterize the resulting ZnO/RGO photocatalyst. Results showed that highly crystalline ZnO nano-flowers were effectively doped on the surface of RGO sheets. The unique properties of RGO sheets not only provide the decreased rate of electron–hole separation in ZnO but also prevent from the loss of photocatalyst during recovery due to the fixed attachment of ZnO NPs on the surface of high aspect ratio graphene sheets. Therefore, as-synthesized composite is an economically and environmentally friendly photocatalyst. [Copyright &y& Elsevier]

Abstract: Multiwalled carbon nanotube/polyurethane (MWNT/PU) composites were prepared by electrospinning and solution casting. The morphological and thermal properties, and mechanical performance of the nanofiber and film composites were characterized and compared. The tensile strength of neat PU film was 9-fold higher than that of neat PU nanofibrous mat. The incorporation of MWNTs increased the tensile strength and modulus of the composite nanofibers by 69% and 140%, respectively, and 62% and 78%, respectively for composite films. The MWNT/PU composites showed an improved thermal degradation behavior, with the incorporation of low MWNT content in the composites. [Copyright &y& Elsevier]

Abstract: In this study, we describe the enhancing ability of electrospun polyurethane (PU) nanofibers containing carbon nanotubes (CNTs) as nanofillers for silicone film in improving the physico-mechanical properties of the composite material. We prepared the samples combining two simple techniques: solution casting and electrospinning. Neat PU nanofibers alone are good reinforcing materials but the presence of CNTs inside the PU nanofibers has drastically improved the mechanical properties of the silicone composite film. The silicone film increased its tensile strength by 226% and its tensile modulus by more than 14-fold when CNT/PU nanofibers were incorporated. [Copyright &y& Elsevier]

Abstract: Here, we report a simple heat-treatment process to prepare hydroxyapatite (HA)-coated Ti6Al4V anterior cruciate ligament (ACL) anchor that has good hard tissue compatibility and biostability. Heat treatment was carried out for 1.5h at temperature range of 700–900°C. Morphological characterization showed rougher surface and larger pore spaces as the heat treatment temperature was increased. The Ti6Al4V heat-treated at 800°C had the highest diffused titanium phosphide formation, thus making it high in biocompatibility. For in vivo test, the most bone integration ability was obtained for heat-treatment at 800 and 900°C. Furthermore, the HA/Ti6Al4V ACL anchor heat-treated at 800°C had the highest amount of new bone formation. The present results suggest that an implant with complex shape like an ACL anchor could be prepared and used with an easy and low-cost technique by simple heat treatment surface modification method after dip-coating with HA. [Copyright &y& Elsevier]

Abstract: In this work, nylon-6 spider-wave-like nano-nets are fabricated by regulating the amount of graphene oxide (GO) in polymer solution during electrospinning. The spider-wave-like nano-nets that comprise interlinked thin (≈14nm diameter) and thick fibers (≈192nm diameter) are widely distributed throughout the mat when suitable amount of GO is blended with nylon-6 solution. The heterogeneous composite mats were composed of bimodal nanofibers in which pore diameter was sufficiently decreased. The acceleration in ionization and degradation of nylon-6 (due to formic acid) solution caused by well-dispersed GO sheet as well as the formation of hydrogen bond between nylon-6 molecules and GO sheet during electrospinning are proposed as the possible mechanisms for the formation of these spider-wave-like nano-nets. [Copyright &y& Elsevier]

Abstract: In this study, TiO2-impregnated ZnO nano-flowers were synthesized by one-pot hydrothermal process. Aqueous suspension containing ZnO precursor and commercial TiO2 NPs (P25) is heated at 140°C for 2h. The morphology and structure of as-synthesized particles were characterized by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD), which revealed that TiO2 NPs were attached on the surface of ZnO flower. It was observed that the presence of TiO2 NPs in the hydrothermal solution could sufficiently decrease the size of ZnO flower. The hybrid nanostructure, with unique morphology, obtained from this convenient method (low temperature, less time, and less number of reagents) was found to be effective photocatalyst under UV-irradiation. [Copyright &y& Elsevier]

Abstract: Uniaxial tensile properties influenced by the dynamic recrystallization (DRX) behavior of the partially strain-hardened magnesium AZ31 sheets (H24) containing scores of twins were investigated and compared to those of fully annealed ones (O) with absence of twins. For this purpose, a series of uniaxial tensile tests were carried out for the H24 and O materials at temperatures ranged from room temperature to 300°C and at strain rates between 10−3 and 10−1 s−1. At 150 and 200°C, the H24 material exhibited higher yield strength without much loss in elongation compared to those of the O material; this trend was attributed to the continuous DRX along or around grain boundaries as well as extensive twin-aided DRX inside grains. In addition, the post-deformation hardness value of the H24 material showed higher than that of the O material. On the other hand, at higher temperatures of 250 and 300°C, it was observed that twins shown in the H24 material were disappeared even prior to deformation, resulting in the similar grain structure and mechanical property values to those of the O material, e.g., discontinuous DRX associated with grain boundary bulging. Finally, the initiation of DRX was rationalized in terms of microstructure morphology, deformation temperature and strain rate, and then modeled in the context of strain hardening rate analysis. A comparison of experimental results and predictions for both H24 and O materials showed that the model can provide a reasonable prediction of critical strain to initiate DRX. [Copyright &y& Elsevier]

This article describes a preliminary investigation and prototype fabrication of a novel potential sensing method to continuously monitor vascular stent fractures. A potential measurement system consisting of Wheatstone bridge circuit and signal conditioning circuit was designed for the cardiovascular stent durability and fatigue test. Each end of a bare and polyurethane-covered Nitinol vascular stent was electrically connected to the potential measurement system and then immersed either in simulated body fluid (SBF) media or distilled water at 36.4±1°C. When the stent experienced fracture (i.e., a cut), its electrical potential decreased with an increase in electrical resistance. This method successfully measured fractures in the stent regardless of location. Furthermore, the number of cycles at the onset of stent fracture was accurately detected and continuously monitored using this technique. Thus, the present fracture detection method, which to our knowledge is the first ever report to use electrical potential measurement for stent durability test, gives a fast, real-time, accurate and efficient detection of fractures in stent during in vitro fatigue and durability test. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the present study is to evaluate the influence of nano-sized carbides upon tensile behavior in UFG medium-carbon steels and to develop a material with improved tensile properties. UFG medium-carbon steels with fine carbides were successfully fabricated by multi-pass caliber rolling at 773K. Alloying chromium and molybdenum resulted in thinner pearlitic lamellae, which were transformed into finer particles after severe plastic deformation. The UFG steel containing the alloying elements exhibited superior tensile properties, which was attributed to the enhanced strain hardening rate by the imbedded finer particles. Subsequent annealing induced growth of grains and particles, which also recovered elongation at the expense of strength. All UFG steels investigated here showed a yield-point phenomenon due to the decreased hardening rate and lack of mobile dislocations and their sources. The deteriorating effect of particle growth overwhelmed the improving effect of grain growth after annealing of the UFG medium-carbon steel, leading to a reduced strain hardening rate. This resulted in a positive correlation between a grain size and Lüders elongation in the investigated UFG steels. [Copyright &y& Elsevier]

Abstract: Measuring the level of radioactive contamination in a high-radiation area with a complex geometry requires a new measuring system that can be operated remotely and free of electronic noise by radiation. In this study, a measuring system suitable for measuring high-level radioactive contamination in the narrow gap of a nuclear facility was developed. The measuring system was a fiber-optic remote system using an organic scintillator, epoxy resin and an optical fiber. The measuring system was tested for Cs-137 and Sr/Y-90 radiation sources, and could measure radioactive contamination remotely in a narrow area. [Copyright &y& Elsevier]

Metallic implantation materials having high yield strength, low elastic modulus, and non-cytotoxic alloying elements would be advantageous for the long-term stability of implants. This study assessed the surface and mechanical properties, and also in vitro osteoconductivity of ultrafine-grained (UFG) Ti-13Nb-13Zr alloy produced by dynamic globularization without any severe deformation for future biomedical applications as an endosseous implant material. The surface characteristics and mechanical properties were investigated by orientation image microscopy, contact angle measurements, optical profilometry, and uniaxial tension tests. Mouse calvaria-derived pre-osteoblastic cell (MC3T3-E1) attachment, spreading, viability, alkaline phosphatase (ALP) activity, and quantitative analysis of osteoblastic gene expression on UFG Ti-13Nb-13Zr alloy were compared with coarse-grained (CG) Ti-13Nb-13Zr and CG Ti-6Al-4V alloys. Dynamic globularized Ti-13Nb-13Zr alloy has an ultrafine grain size (0.3 μm) and an excellent combination of yield strength and elastic modulus compared with CG alloys, which displayed significantly lower water contact angles compared with CG alloys ( P<0.05). The UFG and CG Ti-13Nb-13Zr alloys displayed significantly increased cellular attachment compared with CG Ti-6Al-4V alloy ( P<0.05). The UFG Ti-13Nb-13Zr supported better cell spreading and more numerous focal adhesions. ALP activity ( P<0.05) and mRNA expressions of the osteoblast transcription factor genes (osterix, Runx2) and marker gene for osteoblast differentiation (osteocalcin) were markedly increased in cells grown on the UFG substrate compared with CG substrates at early incubation timepoints. Enhanced pre-osteoblast response to UFG Ti-13Nb-13Zr substrate is attributable to the non-cytotoxic alloying elements and the submicron scale grain size contributes to the superior surface hydrophilicity and abundant grain boundaries favorable for cell behavior. These findings indicate that dynamic globularized UFG Ti-13Nb-13Zr alloy is promising for load-bearing endosseous implant material because of excellent mechanical and biological compatibilites. Park CH, Lee CS, Kim Y-J, Jang J-H, Suh J-Y, Park J-W. Improved pre-osteoblast response and mechanical compatibility of ultrafine-grained Ti-13Nb-13Zr alloy. Clin. Oral Impl. Res. , 2011; 735-742 doi: 10.1111/j.1600-0501.2010.02053.x [ABSTRACT FROM AUTHOR]