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Background The aim of the study is to evaluate the risk factors of anastomotic leakage (AL) and develop a nomogram to predict the risk of AL in surgical management of primary ovarian cancer. Methods We retrospectively reviewed 770 patients with primary ovarian cancer who underwent surgical resection of the rectosigmoid colon as part of cytoreductive surgery between January 2000 to December 2020. AL was defined based on radiologic studies or sigmoidoscopy with relevant clinical findings. Logistic regression analyses were performed to identify the risk factor of AL, and a nomogram was developed based on the multivariable analysis. The bootstrapped-concordance index was used for internal validation of the nomogram, and calibration plots were constructed. Results The incidence of AL after resection of the rectosigmoid colon was 4.2% (32/770). Diabetes (OR 3.79; 95% CI, 1.31–12.69; p = 0.031), co-operation with distal pancreatectomy (OR, 4.8150; 95% CI, 1.35–17.10; p = 0.015), macroscopic residual tumor (OR, 7.43; 95% CI, 3.24–17.07; p = 0https://ALnomogram.github.io/. Conclusion Four risk factors for AL after resection of the rectosigmoid colon are identified from the largest ovarian cancer study cohort. The nomogram from this information provides a numerical risk probability of AL, which could be used in preoperative counseling with patients and intraoperative decision for accompanying surgical procedures and prophylactic use of ileostomy or colostomy to minimize the risk of postoperative leakage. Trial registration Retrospectively registered.

The purpose of this study was to evaluate the surgical outcomes and learning curve of multiport robot-assisted hysterectomy.Eighty-eight patients were identified who underwent multiport robot-assisted surgery for hysterectomy. A retrospective analysis was performed. The cumulative summation technique (CUSUM) was used to investigate the learning curve in surgical proficiency by analyzing total operative, docking, and console times.The patients' median age was 51 years. In addition, the median operative time was 120.5 min (range 56-344 min). The most common indication for surgery was myoma (33.0%). The median estimated blood loss was 30 mL (range 5-200 mL). There was no conversion to laparoscopic or open surgery. No transfusion was required, and only one complication including umbilical incisional hernia was reported. A tendency of decline in total operative time following the first 23 cases was found. The CUSUM graph for total operative time indicated the generation of three distinct performance phases: learning (n = 23), competence (n = 36), and mastery (n = 29). The median docking time was 3 min (range 1-10 min) and median console time was 70 min (range 24-298 min).The multiport robot-assisted surgery is an easy and safe procedure with minimal postoperative complications and can be quickly learned. The learning curve was 23 cases to significantly decrease the operative time.

Background Thyroid abnormality is a common late effect seen in childhood cancer survivors (CCSs). We analyzed the prevalence and risk factors of thyroid abnormalities based on diagnoses and treatment modalities in CCSs. Methods The medical records of 257 CCSs who were diagnosed with cancer less than 20 year of age were retrospectively reviewed. The median age was 11.8 years (0.1–19.8). The median follow-up period after completion of therapy was 9.6 years (5.0–19.5). Results Of 257 subjects, thyroid abnormalities were identified in 107 (41.6%). Sixty-five out of 257 (25.3%) had subclinical hypothyroidism, and 16 (6.2%) developed central hypothyroidism. Five CCSs (1.9%) had primary overt hypothyroidism. Five (1.9%) and 6 (2.3%) CCSs were diagnosed with autoimmune thyroiditis and thyroid cancer, respectively. Among the different diagnostic groups, thyroid abnormalities were frequent in the brain tumor or Hodgkin disease or nasopharyngeal cancer groups. CCSs who received irradiation directly or near hypothalamus-pituitary-thyroid (HPT) axis had more thyroid abnormalities compared to the rest CCSs (P P = 0.0069). Forty-five (42%) of 107 subjects with thyroid abnormalities had normalized thyroid hormone levels at the last follow-up. Irradiation directly or near HPT axis were thought to be a predicting factor of persistent subclinical hypothyroidism. Conclusions Subclinical hypothyroidism was common in CCSs. CCSs with irradiation directly or near HPT axis were at risk for persistent thyroid dysfunction.

Background Ureteral reconstruction is required after surgical resection of the tumor invading the urinary tract in ovarian cancer with low incidence. There are no currently reported surgical outcomes of ureteral reconstruction during cytoreductive surgery. The aim of the study is to investigate the clinical features and surgical outcomes of ureteral reconstruction during primary, interval and secondary cytoreductive surgery for ovarian cancer. Methods A total of 3226 patients who underwent primary, interval or secondary cytoreductive surgery for ovarian cancer between January 2000 and May 2021 were reviewed. Fifty-six patients who underwent ureteral reconstruction during cytoreductive surgery were included in the analysis. Results Ureteral reconstruction was required in 1.7% (56/3226) of ovarian cancer patients. Of the 56 patients who underwent ureteral reconstruction during cytoreductive surgery, 35 (62.5%) had primary ovarian cancer, and 21 (37.5%) had recurrent ovarian cancer. The median tumor size invading the lower urinary tract was 2.0 cm (range, 0.4–9.5 cm). Ureteroneocystostomy with direct implantation (51.8%) and psoas hitch (8.9%), transureteroureterostomy (7.1%), and ureteroureterostomy (32.1%) were required as part of cytoreductive surgery. Complete cytoreduction with ureteral reconstruction was achieved in 83.9% (47/56) and the rest of the patient population (16.1%) achieved a gross residual tumor size of less than 1 cm. All complications, including hydronephrosis (33.9%), were managed, none resulting in long-term sequelae. In primary ovarian cancer, the 5-year disease-free survival and overall survival were 50.0% and 89.5%, respectively. In patients with recurrent ovarian cancer, the 5-year disease-free survival and overall survival were 23.6% and 64.0%, respectively. Conclusions Ureteral reconstruction as a part of cytoreductive surgery for ovarian cancer could be performed with acceptable morbidities. Complete cytoreduction by a multidisciplinary surgical team, including urologic oncologists, should be pursued for the surgical management of ovarian cancer. Trial registration Retrospectively registered.

Model matching for asynchronous sequential machines (ASMs) is to design a corrective controller so as to match the stable-state behavior of the closed-loop system to that of a reference model. In this paper, we discuss the model matching problem for ASMs with discrepancy in the initial state. Owing to a lot of practical constraints, the controlled ASM may not commence its operation at the same initial state as the model, leading to initial model mismatch. We investigate under which condition an appropriate corrective controller can be designed that solves initial model mismatch. If such a condition is not valid, we address delayed model matching in which the closed-loop system is controlled to be stably equivalent with the model within an allowable delay-bound from the initial operation. FPGA experiments on an asynchronous error counter are provided to show the applicability of the proposed control scheme.

Amorphous structures of the as-cast bulk metallic glass samples (BMGs) of Cu60Zr25Ti15 and (Cu60Zr25Ti15)95Ni5 alloys are confirmed by X-ray diffraction. Isothermal crystallization kinetics of these BMGs are investigated using differential scanning calorimetry. For both the alloys, the apparent activation energy (Ea) shows a strong dependency on crystallization volume fraction (x). Isothermal crystallization kinetic parameters are calculated by Arrhenius and Johnson–Mehl–Avrami equations. Avrami exponential factor (n) is also found to show clear correlation with the crystallization volume fraction (x). It is found that the crystallization process is easier in Cu60Zr25Ti15 BMG than in (Cu60Zr25Ti15)95Ni5 BMG as the Ea decreases constantly for the former alloy though in the case of second alloy, the Ea is almost unchanged up to x = 60%. For both the alloys, nucleation activation energy (Enucleation) is found to be higher than that of growth activation energy (Egrowth). This indicates that the growth of crystals during isothermal crystallization in these glasses is easier than nucleation, and the minor addition of Ni causes the higher thermal stability against crystallization in isothermal condition.

Gamma-rays and fast and thermal neutron attenuation features of (Bi2O3)x–(TeO2)(100−x) (where x = 5, 8, 10, 12, and 15 mol%) and [(TeO2)0.7–(B2O3)0.3](1−x)–(Bi2O3)x (where x = 0.05, 0.10, 0,15, 0.20, 0.25, and 0.3 mol%) glass systems have been explored and compared. For all samples, mass attenuation coefficients (μ/ρ) are estimated within 0.015–15 MeV photon energy range by MCNP5 simulation code and correlated with WinXCom results, which showed a satisfactory agreement between computed μ/ρ values by these both methods. Additionally, effective atomic number (Zeff), effective electron density (Neff), half-value layer (HVL), tenth-value layer (TVL), mean free path (MFP), total atomic cross-section (σa), and total electronic cross-section (σe) are calculated by utilizing μ/ρ values. The μ/ρ, Zeff, and Neff are energy dependent and have higher values at the lowest energy and smaller values at higher energies. Moreover, using the G–P fitting method as a function of penetration depth (up to 40 mfp) and incident photon energy (0.015–15 MeV range), exposure buildup factors (EBFs) and energy absorption buildup factors (EABFs) are evaluated. Both 85TeO2–15Bi2O3 (mol%) and 49TeO2–21B2O3–30Bi2O3 (mol%) samples, by possessing higher values of Zeff, exhibit minimum EBF and EABF values. Highest μ/ρ, Zeff values and lowest HVL, TVL, MFP values of 49TeO2–21B2O3–30Bi2O3 (mol%) sample indicated its better gamma-ray absorption capability among all selected glasses. Further, macroscopic effective removal cross-section for fast neutrons (ΣR), coherent scattering cross-section (σcs), incoherent scattering cross-section (σics), absorption cross-section (σA), and total cross-section (σT) values for thermal neutron attenuation have been computed. Among all samples, 49TeO2–21B2O3–30Bi2O3 (mol%) glass possesses a better ΣR value for fast neutron attenuation, while the largest ‘σT’ value of 66.5TeO2–28.5B2O3–5Bi2O3 (mol%) sample suggests its good thermal neutron absorption efficiency.

Earned Value Management (EVM) has been established as a project management technique for project monitoring and control. The traditional EVM performs well in forecasting Cost Performance index and other cost metrics. However, in terms of schedule performance, the accuracy of the forecasted schedule metrics through the traditional EVM approach are always questionable. The schedule performance is not measured in time unit but rather in monetary units or uses cost information, which may cause misleading in the interpretation of the EVM schedule metrics. The schedule performance is not accurately forecasted, resulting in underestimating the estimate at completion (t). Even the renowned Earned Schedule also uses cost as a proxy to determine the earned schedule. This paper presents a new EVM tool, Duration estimate at completion (DEAC-model) developed to accurately forecast the time estimate at completion. DEAC-model uses the actual time spent on each activity, either in progress or upon completion, where the Performance is measured in time units. The benefits of DEAC-model to project management team and researchers are that it can be used: 1) to forecast schedule metrics accurately so that resources can be effectively allocated to complete the remaining activities, 2) as a gauge to assess if the project can be completed within the plan schedule, and 3) to apply time series and simple linear regression model concepts using excel worksheet syntax to forecast duration estimate at completion that is easily applicable.

This study explores changes in means and extreme events of human-sensible temperature (HST), which is quantified by selective combination of Universal Apparent Temperature, Heat Index, and a new Wind Chill Index, in Korea for the last 100 years (1919-2018) and illustrates the synoptic patterns of the East Asian monsoon system (EAMS) for extreme HST events. The time series analyses show that HST has increased much faster than near-surface air temperature (AT) in winter due to decrease in wind chill as well as to increase in AT. On the other hand, HST in summer, which is higher than AT on average because of high humidity in monsoon climate, has increased at a slow rate compared with those in other seasons. However, more extremely hot, long-lasting HST events have been observed in recent decades, as in 1994, 2013, 2016, and 2018, with shorter recurrent intervals. Greater increases of HST than AT are more distinct in the southern region under maritime subtropical climate than in the temperate climate zone in the north in all seasons. Composite maps for multiple high or low HST extreme events reveal that a dipole pressure anomaly pattern, rather than the intensity at the center of these air masses, is more closely related to the frequency of extreme HST events in Korea: A west high-east low pattern in winter formed by the expansion of the Siberian High accompanying an intense migratory low pressure system, and a south high-north low pattern formed by the westward intrusion of the Northwest Pacific subtropical high in summer after earlier terminations of summer rainy period (Changma). These indicate that monitoring of changing EAMS's characteristics is crucial to the mitigation of potential damages caused by unprecedented HST extreme events in the warmer twenty-first century.

Authors aim to study multicomponent barium bismuth borate glasses doped with Dy3+ (1 mol%) for white light-emitting diodes (WLEDs) application. All samples, synthesized through melt-quench approach, were characterized by XRD, optical absorption, excitation, emission, and decay lifetimes. Oscillator strengths and Judd–Ofelt intensity parameters (Ω2, Ω4, Ω6) for all glasses were computed from absorption spectra and further, radiative emission transition probability (AR), branching ratio (βR), and radiative lifetime (τR) were estimated for Dy3+ ion various excited states using J–O parameters. Upon 350 nm excitation, 4I15/2 → 6H15/2 [454 nm (blue)], 4F9/2 → 6H15/2 [483 nm (blue)], 4F9/2 → 6H13/2 [575 nm (yellow)], and 4F9/2 → 6H11/2- [663 nm (red)] emission transitions were observed among which 4F9/2 → 6H13/2 transition exhibits the highest intensity. Dy3+: Li glass showed relatively higher PL intensity and quantum efficiency than Dy3+: Na and Dy3+: K samples. Calculated CIE chromaticity (x = ~ 0.35, y = ~ 0.39) coordinates (λex.: 350 nm) and CCTs (4749‒4890 K) proclaimed overall neutral white light emission from all samples, implying their suitability for WLED applications. Decay lifetimes (τexp) were determined for Dy3+: 4F9/2 → 6H13/2 transition. Additionally, stimulated emission cross-section ($$\sigma^{\text{E}}_{\text{p}}$$) and gain bandwidth ($$\sigma^{\text{E}}_{\text{p}}$$ × Δλeff) were calculated for respective blue and yellow emission transitions.

In this paper, a series of combustion tests using PMMA/O2 was conducted to examine the initiating characteristics of low frequency instability (LFI) in relation to the changes in both flow and combustion conditions. By selecting parameters such as the oxidizer mass flow rate, fuel grain length, and mixing ratio of mixture oxidizer composed of oxygen and nitrogen; combustion tests were conducted to vary the equivalence ratio in the combustion. This study further validated instability characteristics in connection with coupling behavior between the high frequency pressure and heat release oscillations in 500 Hz band. Based on the results, a combustion stability map was plotted and it shows that the initiation of LFI is contingent upon the satisfaction of specific conditions of flow and combustion. The results also confirmed that the initiation of LFI is highly linked to an establishment of a positive coupling between high frequency pressure and heat release oscillations. In addition, equivalence ratio was found to be a critical factor in the transition of coupling status between the two high frequency oscillations. For a given flow condition, the sole increase in equivalence ratio above a certain threshold resulted in the phase shift between the two oscillations leading to a positive coupling or vice versa.

Computing the productivity of a dozer involves correcting a set of multivariate values. The existing dozer-productivity computation models utilize unique sets of input variables, formulae, and experimental data. However, these are considered appropriate only for performing comparative studies, not for obtaining a precise productivity value. With a set of input variables obtainable from a job site, it is important for an earthwork manager to quickly identify a model that computes the dozing productivity and to compute the productivity by implementing the model. Expediting the productivity computation intertwines with the determination of eco-dozing performance, which relates to the fuel consumption per unit earthwork production. This paper presents a dozer-productivity correction method (DPCM) that computes the variations between the existing productivity models. This method can determine the sensitivity in selecting a model to compute the productivity. This study is of value to researchers because it considers the productivity-correction factors exhaustively and consistently while expediting the computation. It is also of relevance to earthwork managers because it illustrates the variability in the outputs from different models. Hence, it facilitates the estimation of fuel efficiency of a dozing operation. The test case verifies the validity of the computational method.

This study aimed to compare the sentinel lymph node (SLN) identification rates for breast cancer patients after neoadjuvant chemotherapy (NAC) between the dual method (DM) of indocyanine green fluorescence (ICG-F) plus a radioisotope (RI) and RI alone. This randomized study enrolled 130 patients who received NAC for breast cancer and 122 patients who received SLN biopsy (SLNB) using either DM (n = 58) or RI only (n = 64). The study compared the identification rate, number of SLNs, and detection time of SLNB. Among the 122 patients, 113 (92.6%) were clinically node-positive before NAC. The SLN identification rate was 98.3% in the DM group and 93.8% in the RI group (p = 0.14). The DM group and the RI group were similar in the average number of SLNs (2.2 ± 1.13 vs. 1.9 ± 1.33; p = 0.26) and the time to detection of the first SLN (8.7 ± 4.98 vs. 8.3 ± 4.31 min; p = 0.30). In the DM group, transcutaneous lymphatic drainage was visualized by fluorescence imaging for 65.5% (38 of 58) of the patients. The SLN identification rate was 94.7% using ICG-F and 93% using RI (p = 0.79). During and after the operation, no complications, including allergic reactions or skin necrosis, occurred. This study is the first randomized trial to use ICG-F for SLNB in breast cancer patients after NAC. The DM including ICG-F could be a feasible and safe method for SLNB in initially node-positive breast cancer patients with NAC.

Highly accurate detection of the intracranial hemorrhage without delay is a critical clinical issue for the diagnostic decision and treatment in an emergency room. In the context of a study on diagnostic accuracy, there is a tradeoff between sensitivity and specificity. In order to improve sensitivity while preserving specificity, we propose a cascade deep learning model constructed using two convolutional neural networks (CNNs) and dual fully convolutional networks (FCNs). The cascade CNN model is built for identifying bleeding; hereafter the dual FCN is to detect five different subtypes of intracranial hemorrhage and to delineate their lesions. Using a total of 135,974 CT images including 33,391 images labeled as bleeding, each of CNN/FCN models was trained separately on image data preprocessed by two different settings of window level/width. One is a default window (50/100[level/width]) and the other is a stroke window setting (40/40). By combining them, we obtained a better outcome on both binary classification and segmentation of hemorrhagic lesions compared to a single CNN and FCN model. In determining whether it is bleeding or not, there was around 1% improvement in sensitivity (97.91% [± 0.47]) while retaining specificity (98.76% [± 0.10]). For delineation of bleeding lesions, we obtained overall segmentation performance at 80.19% in precision and 82.15% in recall which is 3.44% improvement compared to using a single FCN model.

In this research, thermally conductive polyamide 6/hexagonal boron nitride (PA6/hBN) nanocomposites waaere fabricated via an in-situ ring-opening polymerization of e-caprolactam. The hBN filler was exfoliated through a co-solvent exfoliation process and then chemically modified to form an e-caprolactam-grafted BN (cBN). After that, PA6 was introduced onto the cBN surface using a grafting from method. The thermal conductivities of the PA6/cBN composites significantly increased up to 180 % when the BN content was 16.5 wt%. The tensile strength and Young’s modulus of the PA6/cBN composites with 16.5 wt% hBN increased by 30 % and 92 %, respectively, compared to the pristine PA6. The grafted PA6 on BN composites exhibited strong polymer-filler interfacial interactions. Overall, this study provides a facile method of fabricating high-performance PA6 with improved thermal and mechanical properties and higher thermal conductivity.

Background Laparoscopic surgery for T4 colon cancer may be safe in selected patients. We hypothesized that small tumor size might preoperatively predict a good laparoscopic surgery outcome. Herein, we compared the clinicopathologic and oncologic outcomes of laparoscopic and open surgery in small T4 colon cancer. Methods In a retrospective multicenter study, we reviewed the data of 449 patients, including 117 patients with tumors ≤ 4.0 cm who underwent surgery for T4 colon cancer between January 2014 and December 2017. We compared the clinicopathologic and 3-year oncologic outcomes between the laparoscopic and open groups. Survival curves were estimated using the Kaplan–Meier method and compared using the log-rank test. Univariate and multivariate analyses were performed using the Cox proportional hazards model. A p < 0.05 was considered statistically significant. Results Blood loss, length of hospital stay, and postoperative morbidity were lower in the laparoscopic group than in the open group (median [range], 50 [0–700] vs. 100 [0–4000] mL, p < 0.001; 8 vs. 10 days, p < 0.001; and 18.0 vs. 29.5%, p = 0.005, respectively). There were no intergroup differences in 3-year overall survival or disease-free survival (86.6 vs. 83.2%, p = 0.180, and 71.7 vs. 75.1%, p = 0.720, respectively). Among patients with tumor size ≤ 4.0 cm, blood loss was significantly lower in the laparoscopic group than in the open group (median [range], 50 [0–530] vs. 50 [0–1000] mL, p = 0.003). Despite no statistical difference observed in the 3-year overall survival rate (83.3 vs. 78.7%, p = 0.538), the laparoscopic group had a significantly higher 3-year disease-free survival rate (79.2 vs. 53.2%, p = 0.012). Conclusions Laparoscopic surgery showed similar outcomes to open surgery in T4 colon cancer patients and may have favorable short-term oncologic outcomes in patients with tumors ≤ 4.0 cm.

This paper reports the crystallization kinetics of (Cu60Zr25Ti15)99.3Nb0.7 bulk metallic glass under isothermal conditions. Differential scanning calorimetry (DSC) has been employed for isothermal annealing at ten different temperatures prior to the onset of crystallization (To) temperature. X-ray diffraction and transmission electron microscopy have been used to confirm the amorphous structure of the as cast sample. Crystallized volume fractions (x) are calculated from the exothermic peaks of DSC scans. Crystallized volume fractions (x) against time show sigmoidal type of curves as well as the curves become steeper at higher annealing temperatures. Continuous heating transformation diagram has been simulated to understand the stability of the bulk metallic glass. Crystallization kinetics parameters are calculated using Arrhenius and Johnson–Mehl–Avrami equations. Activation energy (Ea) and Avrami exponential factor (n) have exhibited strong correlation with crystallized volume fraction (x). The average activation energy for isothermal crystallization is found to be 330 ± 30 kJ/mol by Arrhenius equation. Nucleation activation energy (Enucleation) is found to be higher than that of growth activation energy (Egrowth). The Avrami exponential factor (n) indicates about the diffusion controlled mechanism of the nucleation and three-dimensional growth.

For 25 Li2O–(75 − x) B2O3–x Bi2O3 (where x = 0, 5, 10, 15, 20, 25, 30, 35, and 40 mol%) glasses, gamma-ray and neutrons attenuation features were explored by theoretical approach using ParShield/WinXCOM program, Geant4, and Penelope codes. At 133Ba (276, 303, 356, and 384 keV), 22Na (511 and 1280 keV), 137Cs (662 keV), 54Mn (835 keV), and 60Co (1170 and 1330 keV) photon peaks, for all samples, mass attenuation coefficient (μ/ρ), effective atomic number (Zeff), effective electron density (Neff), half-value layer (HVL), and mean free path (MFP) parameters have been evaluated using ParShield/WinXCOM program. The μ/ρ values computed by WinXCOM, Geant4, and Penelope codes were compared to check the accuracy, and satisfactory agreement among the values was identified. Moreover, using G–P fitting method as a function of penetration depth (1, 5, 10, 15, 20, 25, 30, 35, and 40 mfp) within the photon energy range of 0.015–15 MeV, exposure buildup factor (EBF) and energy absorption buildup factor (EABF) were derived. For all selected glasses, the effectiveness of the neutrons attenuation has been discussed in terms of macroscopic effective removal cross-section (ΣR), coherent scattering cross-section (σcs), incoherent scattering cross-section (σics), absorption cross-section (σA), and total neutron cross-section (σT). The ‘σT’ values have been calculated within 10−4–10−8 MeV neutron energy range using the Geant4 code. The μ/ρ possessed larger values at the lowest energy and lower values at higher energy regions for all studied glasses. The μ/ρ, Zeff, HVL, and MFP values showed enhanced γ-ray shielding capability with Bi2O3 content increment in the samples. The 25 Li2O–35 B2O3–40 Bi2O3 (mol%) sample by having larger Zeq and/or Zeff value, faired lower EBF and EABF values. Largest μ/ρ and Zeff, and minimal HVL, MFP, EBF, and EABF values of 25 Li2O–35 B2O3–40 Bi2O3 (mol%) glass demonstrated its superior γ-ray attenuation ability among all examined glasses. Further, among all glasses, 25 Li2O–75 B2O3 (mol%) sample exhibits relatively higher ΣR (0.11326 cm−1) and ‘σT’ (46.109 cm−1 → 0.84607 cm−1 from 1 × 10−8 MeV → 1×10−4 MeV neutron energy) values for fast and thermal neutrons attenuation, respectively, indicating its better neutrons absorption competence.

For Pb-free 35B2O3‒35Bi2O3‒(30–x)TeO2‒(x)BaO (x = 5, 10, 15, 20, and 25 mol%) and (90–x)TeO2‒10Bi2O3‒(x)BaO (x = 10, 15, and 20 mol%) glass systems, gamma and neutron (both fast and thermal neutron) radiation shielding features were examined and compared. Within 0.015–15 MeV photon energy, mass attenuation coefficients (μ/ρ), for all samples, which have been assessed using WinXCOM program are in fair agreement with deduced MCNP5 simulation code μ/ρ results. For all selected samples, at the lowest energy, μ/ρ has bigger values whereas at higher energy regions possess lower values. Furthermore, by employing μ/ρ values, effective atomic number (Zeff), effective electron density (Neff), half-value layer (HVL), tenth-value layer (TVL), and mean free path (MFP) are figured out for both glass systems. For studied samples, with the gradual replacement of TeO2 content with BaO, the derived values of Zeff, HVL, TVL, and MFP revealed improved γ-ray shielding potentiality. Besides, within photon energy range of 0.015–15 MeV, exposure build-up factors (EBFs) and energy absorption build-up factors (EABFs) were estimated for all samples by utilizing G‒P fitting method as a function of different penetration depths (0.5, 1, 2, 3, 4, 5, 6, 7, 8, 10, 15, 20, 25, 30, 35, and 40 mfp). The 35B2O3–35Bi2O3–5TeO2–25BaO (mol%) glass relatively larger μ/ρ and Zeff values, lower HVL, TVL, and MFP values, and minimal EBF and EABF values confirm its superior γ-ray attenuation competence among all samples. Additionally, in comparison, HVL and MFP values of 35B2O3–35Bi2O3–5TeO2–25BaO (mol%) sample are lower than the respective values of some commercial γ-ray shielding glasses and different types of standard concretes, signifying its better shielding features than them. Moreover, macroscopic removal cross-section for fast neutrons (ΣR), coherent scattering cross-section (σcs), incoherent scattering cross-section (σics), absorption cross-section (σA), and total cross-section (σT) for thermal neutrons absorption were derived for both glass systems. Among all selected glasses, 35B2O3–35Bi2O3–5TeO2–25BaO (mol%) sample possesses relatively higher ΣR (0.106 cm−1) and ‘σT’ (8.809 cm−1 at 0.0253 eV neutron energy) values for fast and thermal neutrons attenuation, respectively, demonstrating its favorable absorption capability for neutrons.

The accuracies of driver’s gaze detection by previous researches are affected by the various sitting positions and heights of drivers in case that initial calibration of driver is not performed. By using dual cameras, the driver’s calibration can be omitted, but processing time with complexity is increased. In addition, the problem of disappearing corneal specular reflection (SR) in the eye image as the driver severely turns his/her head has not been dealt in previous researches. To consider these issues, we propose a gaze tracking method based on driver’s one-point calibration using both corneal SR and medial canthus (MC) based on maximum entropy criterion. An experiment with collected data from 26 subjects (wearing nothing, glasses, sunglasses, hat, or taking various hand pose) in a vehicle, showed that the accuracy of the proposed method is higher than that of other gaze tracking methods. In addition, we showed the effectiveness of our method in the real driving environment.

This paper presents a computational method called Stochastic Multi-variate Performance Trade-off (SMPT), which identifies optimal sets of construction methods for activities, hence appropriately trading-off the project completion time, cost, environmental impact, and quality. SMPT computes exact solution(s), near-optimal solution(s), and stochastic optimal solution(s) using an enumerative analysis, genetic algorithm, and simulation, respectively. This study is of value to project planners because SMPT identifies the sets of construction methods that satisfy user-defined constraints relative to specific performance indicators. SMPT is also of relevance to researchers because it facilitates experiments using different performance indicators, either jointly or independently. Three test cases verify the validity of the computational methods.

Worker safety awareness issue in construction job site is a major concern due to the hazardous work conditions attributed to the dynamic and complex nature of construction job sites. Providing intuitive knowledge expressed as linguistic statements would be useful for corrective and/or preventive actions. This study investigates 98,189 serious injury and fatal accidents that occurred in Korean building construction sites in the period 2006–2010 in order to discover intuitive knowledge expressed as association rules among multi-attributes of construction accidents. 74 association rules are identified as valid by computing the minimum support, confidence, and lift of each rule. Finally, 30 consolidated association rules are obtained as meaningful knowledge for implementing corrective and preventive actions for effective job site safety management after either combining or pruning those 74 rules. This study provides the theoretical rule base that defines the association among accident attributes causing serious injuries and fatalities at construction job site. These rules may be useful for efficient safety control and education.

The staged Hybrid rocket engine (HRE) is a relatively new concept that minimizes a loss of combustion performance with an oxidizer to fuel ratio shifting, while maintaining the key advantages of HREs. Knowing that a key component of the staged HRE is the secondary combustion, in this study a reacting flow Computational fluid dynamics (CFD) based tool was developed to analyze and to predict the performance of staged HRE secondary combustion. Using an equilibrium-chemistry one stream Probability density function (PDF) combustion model, the reacting flow CFD modelling has been done under eight different test conditions. After extensive validations both with non-reacting flow experimental and numerical data and with combustion experiments, this study finds that the CFD-based tool provides satisfactory predictions about the combustion efficiency of staged HRE secondary combustion. The results of both the CFD-based tool and combustion experiments showed a very similar tendency to combustion efficiency under the same test conditions, with an exception that the CFD-based tool seems to overestimate the combustion performance by 11-25 % compared to the combustion experiment. These differences are likely due to overestimation of the one-stream PDF model and oversimplification of the CFD modeling as well as measurement uncertainty in the experiments.

The construction industry has significant effects on global warming, and efforts are being made continuously to reduce environmental load. However, it is difficult to assess the environmental load at the planning phase of Social Overhead Capital (SOC) because it is impossible to obtain the necessary information for calculating the amount of resources used. In this study, a forecast model based on Case-based Reasoning (CBR) was developed and its reliability was evaluated. The purpose of this model is to estimate environmental load accurately and rapidly through Life Cycle Assessment (LCA) by using only 11 types of information for deduction during the planning phase for the road earthwork section of the SOC. The value of environmental load estimated by the asdeveloped model showed an average error of 19.21%. The reliability is approximately 18%P higher than that of the value estimated based on the basic unit (/m, /m2) that can be used at the planning phase. Thus, the capability to perform environmental load assessment through LCA with better reliability even with information that can be used at the planning phase of road facilities through the as-developed CBR-based environmental load estimation model is demonstrated.

The authors aim to study the gamma-rays and neutron beam shielding capabilities of zinc bismuth borate glasses doped with erbium ions. Mass attenuation coefficient (MAC) (μ/ρ) values were computed employing XCOM and two different simulation codes, MCNP5 and Geant4, within 0.015–15 MeV photon energy, which showed good agreement within the derived values. The effective atomic number (Zeff), electron density (Ne), half-value layer (HVL) and mean free path (MFP) values were derived using MAC values. To account on the scattering effects of photons from the samples, exposure buildup factor (EBF) were determined, applying geometric progression (G-P) method, within 0.015–15 MeV photon energy and penetration depth of 1–40 mfp (intervals: 1, 5, 10, 15, and 40 mfp). The high MAC, Zeff values and low HVL, MFP values of 16.93B2O3‒22.57ZnO‒60Bi2O3‒0.5Er2O3 (mol%) glass optimized its shielding effects against gamma-rays. The macroscopic effective removal cross-section for fast neutron (ΣR) values lie within the range of 0.1142–0.1232 cm−1 for the selected Er2O3-doped samples. The studied parameters of the experimented glasses revealed their dominant radiation shielding features compared to commercial shielding glasses, concretes, and alloys.

Background The differences in progression-free survival (PFS) and cancer-specific survival (CSS) of metastatic renal cell carcinoma (mRCC) patients according to treatment, type of metastasis, and Heng criteria risk are unclear. In this study, we compared survival according to various such parameters. Methods Between 2000 to 2014, 214 mRCC patients, of whom 171 (79.9%) were intermediate-risk and 43 (20.1%) were poor-risk, were retrospectively selected; 126 (58.9%) patients were treated with immunotherapy (IT) and 88 (41.1%) with targeted therapy (TT). Moreover, 144 patients had synchronous mRCCs (67.3%, SM) and 70 had metachronous mRCCs (32.7%, MM). The Kaplan-Meier method and log-rank test were used to compare progression-free survival (PFS) and CSS. Results During a median 4.2 (1.0–70.4) months of systemic treatment and 98.3 (4.8–147.6) months of follow-up, the median PFS and CSS were 4.7 (95% confidence interval [CI]: 3.8–5.5) and 13.8 (95% CI, 9.8–18.3) months, respectively. The PFS and CSS were significantly better in the MM (5.9 and 21.3 months) and intermediate-risk groups (5.2 and 18.3 months) than those in the SM (4.4 and 9.6 months) and poor-risk groups (2.7 and 5.8 months), respectively (p 0.05). Conclusion Dividing patients into specific subcategories helps to better predict therapeutic outcomes. Electronic supplementary material The online version of this article (10.1186/s12885-019-5900-1) contains supplementary material, which is available to authorized users.

Many researchers have focused on the role of adipocytes in increasing efficient bone tissue engineering and osteogenic differentiation of stem cells. Previous reports have not reached a definite consensus on whether adipocytes positively influence in vitro osteogenic differentiation and in vivo bone formation. We investigated the adipocyte influence on osteogenic differentiation from adipose-derived stromal cells (ADSCs) and bone formation through histological analysis in vitro and in vivo. Using the direct co-culture system, we analyzed the influence of adipocytes to promote the differentiation fate of ADSCs. Using co-transplantation of ADSC-derived adipocytes and osteoblasts into the dorsal region of mice, the osteogenesis and bone quality were determined by histological morphology, radiography, and the measurement of the Ca2+ concentration. The adipocyte negatively affected the osteoblast differentiation of ADSCs in the in vitro system and induced osteogenesis of osteoblasts in the in vivo system through co-transplantation. Interestingly, in the co-transplanted adipocytes and osteoblasts, the bone formation areas decreased in the osteoblast only group compared with the mixed adipocytes and osteoblast group 6 weeks after transplantation. Conversely, co-transplantation and osteoblast transplantation had similar degrees of calcification as observed from radiography analysis and the measurement of the Ca2+ concentrations. Our results revealed that adipocytes inhibited osteoblast differentiation in vitro but enhanced the efficacy of osteogenesis in vivo. In addition, the adipocytes controlled the activity of osteoclasts in the newly formed bone tissue. Our approach can be used to reconstruct bone using stem cell-based tissue engineering and to enhance the understanding of the role adipocytes play.

Against the background of accelerating global warming due to the effect of greenhouse gases, efforts to reduce greenhouse gas emissions are being made worldwide. Among public works, road construction, which involves numerous processes, leads to greenhouse gas emission. Although many studies have been conducted on earth work in road construction few studies on have dealt with paving work. The purpose of this study is to propose an optimum equipment combination selection method that simultaneously considers the construction cost, construction period, and environmental load of paving equipment used for paving construction. Standards of estimate and price information were used to estimate the construction cost and period, and a LCI database was used to estimate environmental load. The result showed that construction period and cost were proportionally interrelated, but the environmental load was inversely proportional. Accordingly, the optimum area was established for which the numerical values of the construction period and cost and environmental load can appropriately be considered. It is expected that the proposed selection method for paving work equipment combination will be helpful in selecting combinations that can consider both economic feasibility and the environmental effect.

This study was conducted to evaluate the preventive effect of hesperetin against radiation-induced DNA damage and immune dysfunction in murine splenocytes. Isolated splenocytes from BALB/c mice were treated with hesperetin (20, 100, and 500 µM), and then irradiated at a dose of 2 and 4 Gy of γ-irradiation. Exposure to ?-radiation resulted in DNA damage and a reduction of cell viability as well as an elevation of the levels of proinflammatory cytokines, intracellular ROS (reactive oxygen species), and NO (nitric oxide). Hesperetin significantly enhanced the cell viability of the splenocytes compared with the irradiated group. In addition, hesperetin was found to be highly effective in preventing DNA damage as identified by comet and DNA ladder assays. Hesperetin also effectively inhibited proinflammatory cytokines, intracellular ROS, and NO in irradiated splenocytes. In conclusion, hesperetin was shown to be radioprotective against irradiation-induced DNA damage and immune dysfunction in murine splenocytes.

Metabolic labeling is one of the most powerful methods to label the live cell for in vitro and in vivo tracking. However, the cellular mechanisms by modified glycosylation due to metabolic agents are not fully understood. Therefore, metabolic labeling has not yet been widely used in EPC tracking and labeling. In this study, cell functional properties such as proliferation, migration and permeability and gene expression patterns of metabolic labeling agent-treated hUCB-EPCs were analyzed to demonstrate cellular effects of metabolic labeling agents. As the results, 10 μM Ac4ManNAz treatment had no effects on cellular function or gene regulations, however, higher concentration of Ac4ManNAz (>20 μM) led to the inhibition of functional properties (proliferation rate, viability and rate of endocytosis) and down-regulation of genes related to cell adhesion, PI3K/AKT, FGF and EGFR signaling pathways. Interestingly, the new blood vessel formation and angiogenic potential of hUCB-EPCs were not affected by Ac4ManNAz concentration. Based on our results, we suggest 10 μM as the optimal concentration of Ac4ManNAz for in vivo hUCB-EPC labeling and tracking. Additionally, we expect that our approach can be used for understanding the efficacy and safety of stem cell-based therapy in vivo.

In regards to the guideline for computing carbon emission amount by Ministry of Land, Infrastructure and Transport (MLIT) and existing studies on the computation of environmental load of road facilities, they present computation methods based on construction output volume finalized after the design development. Accordingly, they are not being helpful in the decision making of the environmental economics of road facilities in the planning stage in which specific information on construction output volume is lacking. Based on literature analysis of existing studies and consultation from a group of construction environmental professionals, 12 types of property information considered to be related to environmental load were selected from an inventory of information that will be available in the road planning stage. In addition, multiple regression analysis was performed based on the environmental load computed through the Life Cycle Assessment (LCA) of 40 national highway project cases of Korea to deduce five impact factors of environmental load in the road facilities planning stage, namely administrative district, road height, road division, geographical feature and design speed. This paper presented a foundation on which environmental economics can be assessed by quantifying in the planning stage environmental load expected to occur from road construction project.

We use a multilevel vector autoregressive model (VAR-L), to forecast sea surface temperature anomalies (SSTAs) in the Atlantic hurricane Main Development Region (MDR). VAR-L is a linear regression model using global SSTA data from L prior months as predictors. In hindcasts for the recent 30 years, the multilevel VAR-L outperforms a state-of-the-art dynamic forecast model, as well as the commonly used linear inverse model (LIM). The multilevel VAR-L model shows skill in 6–12 month forecasts, with its greatest skill in the months of the active hurricane season. The optimized model for the best long-range skill score in the MDR, chosen by a cross-validation procedure, has 12 time levels and 12 empirical orthogonal function modes. We investigate the optimal initial conditions for MDR SSTA prediction using a generalized singular vector decomposition of the propagation matrix. We find that the added temporal degrees of freedom for the predictands in VAR12 as compared with a LIM model, which allow the model to capture both the local wind–evaporation–SST feedback in the Tropical Atlantic and the impact on the Atlantic of an improved medium-range ENSO forecast, elevate the long-range forecast skill in the MDR.

This paper presents a computational method that calculates the amount of carbon emission generated in a construction project. It is coded into carbon emission estimation system (CE2) that makes use of schedule information exported from Primavera P6, integrates either the deterministic amount of greenhouse gas (GHG) emissions generated by resources (i.e., material, equipment, and labor) on activities obtained from P6 database or the stochastic amount of GHG emissions obtained from discrete event simulation-based construction operation models, performs CPM calculations, and calculates the daily and cumulative amount of carbon emissions for each and every activity. This study is of value to researchers because it allows quantifying the total carbon generated in a construction project by considering all types of resources to be used in construction operations. The study is also of relevance to practitioners because it enables to establish engineering schedule that limits carbon emissions at construction phase expeditiously. A test case verifies the usability and validity of the computational methods implemented in the system. It is confirmed that CE2 effectively handles the variability of GHG using deterministic or stochastic data either jointly or independently.

A data-driven, high-order vector auto-regressive (VAR) model is evaluated for predicting the Northern Hemisphere summer time (May through September) low frequency (>10 days or so) variability. The VAR model is suitable for linear stationary time series, similar to the commonly used linear inverse model (LIM), with additional temporal information incorporated to improve forecast skill. The intraseasonal forecast skill of the 250/750 hPa streamfunction is investigated using observational data since 1979, which shows significant improvements in high-order VAR models than the first-order model LIM. Furthermore, the tropical diabatic heating is found to significantly improve the forecast skill of the atmospheric low frequency circulation when included in the VAR model. The forecast skill of 250 hPa streamfunction at Arabian Peninsula is particularly enhanced for up to 5 weeks lead-time through circumglobal wave propagation associated with the persistent tropical eastern Pacific and equatorial Atlantic heating anomalies and the intraseasonal evolution of the tropical Indian Ocean and western Pacific heating anomalies.

Carbon dioxide is a variable gas, and has increased by about 12% every year since 1958. As the atmospheric concentration of carbon dioxide has steadily increased, it is regarded as the major cause of global warming. To reduce the emission of carbon dioxide that is the major cause of global warming, the emission characteristics of carbon dioxide need to be investigated. Especially, the carbon dioxide emission of the equipment used in the execution stage of a construction project is in some degree proportional to fuel consumption, but there exist certain factors that are not proportional to fuel consumption. The methods for calculating carbon dioxide emission include a method using chemical formulas, a method using the Intergovernmental Panel on Climate Change (IPCC) emission factors, and a direct measurement method. Among these three CO2 calculation methods, the indirect methods have the advantage of easy calculation, but the disadvantage of low reliability, while the direct method has the advantage of accurate information, but the disadvantages of requiring a lot of time and cost and the limitations of measurement. In this study, to overcome the disadvantage of the indirect measurement methods, CO2 emission was measured using the direct measurement method, and the CO2 emission characteristics of equipment were analyzed. Also, by comparing them with the values calculated using the indirect methods, the differences between the direct method and the indirect methods were analyzed.

Chronic ultraviolet (UV) light causes skin photoaging, characterized by fine and coarse wrinkle formation and dryness. In this study, the effect of fermented Gelidium amansii and Cirsium japonicum extract mixture (FGCM) with lactic acid bacteria on UVB-induced photoaging was evaluated in human dermal fibroblasts and SKH-1 hairless mice. In vitro, FGCM increased type I procollagen levels and suppressed UVB-induced matrix metalloproteinase-1 (MMP-1) expression more effectively than G. amansii and C. japonicum extract mixture (GCM). In vivo, oral administration of FGCM significantly inhibited UVB-induced the number and total depth of wrinkles in the dorsal skin of mice. FGCM suppressed UVB-induced epidermal thickening, and attenuated UVB-induced MMP-13 expression and MMP-2 and MMP-9 activities in dermal tissue. Furthermore, FGCM increased skin hydration and blocked transepidermal water loss in the dorsal skin of mice compared with the UVB-irradiated group. These data indicate that FGCM exerts potent anti-photoaging activities by improving wrinkle formation and dryness.

This paper examines the effects of changes in the construction economy (e.g., upturns and downturns) on labor operating rates, labor productivity, and cost productivity. The paper investigates the effects of sharp changes in Korea’s construction economy over the last two decades by using the well accepted leading and coincident economic indices such as the annual contract volume and total employment at the national level and assesses operating rates, labor productivity, and cost productivity for three groups of workers working with reinforced concrete (rebar workers, carpenters, and concrete workers) by using the work sampling method, the job site operation measurement, and interviews with field personnel. The results have important implications for effective job site management strategies and provide some guidelines for responding to changes in workers’ behaviors and attitudes.

This paper presents a fuzzy risk assessment model for construction projects. The model combines the fuzzy weighted average principle with a similarity measure of generalized fuzzy numbers. The failure probability of each project objective can be evaluated using a discrete fuzzy weighted average algorithm and translated into an appropriate fuzzy linguistic term by using a modified similarity measure determined by considering the area, perimeter, height, and geometric distance of generalized fuzzy numbers. This paper makes practical contributions by suggesting a model that can address the uncertainty associated with construction projects based on fuzzy set theory and facilitate the assessment of fuzzy risks by allowing for sophisticated computations and theoretical contributions by enabling researchers to expeditiously assess project risks. A test case verifies the usability and validity of the proposed method.

Graduate programs in construction can be designed to incorporate a broad range of subjects, including construction management, construction engineering, and other management subjects. However, few studies were performed previously on the graduate education in construction management and the operation of graduate programs. Thus, a study is necessary to evaluate current construction management programs at the graduate level before discussing how to develop them further. This study aims at identifying leading construction management programs in the US by using a relevant ranking method and investigating how they manage and operate graduate programs in universities. The authors have developed a survey questionnaire to identify overall facts regarding graduate program management. The major findings obtained from surveying 16 schools are illustrated and explained in detail in this paper. The results obtained from the survey are expected to provide useful information to a practical side as well as an academic side. They become an important asset if a university has a plan to launch a new construction graduate program or there are some schools that intend to reflect their current situations by comparing with other peer institutions. For a practical purpose, they will provide useful information to people considering construction as their higher degrees.

A mathematical model is developed to calculate temperature distribution of a slab in a hot rolled reheating furnace by considering thermal radiation in the furnace and transient conduction in the slab. The furnace is modeled as a radiating medium with spatially varying temperature. Radiative heat flux within the furnace, including the effects of the furnace walls, combustion gases, skid beams, and buttons, is calculated through finite volume method with weighted sum of gray gases model and is applied as the boundary condition in the transient conduction equation of the slab. After validating the predictions of the present models with experimental data, the variations in the heating characteristics of the slab are investigated with residence time in the furnace at two different charging and furnace gas temperatures. The optimum residence time for the slab in the furnace is examined with regard to slab exit temperature, temperature difference between the upper surface and centerline of the slab, and skid mark.

The assumption of the normality of the distribution of Project Completion Times (PCTs) in simulation-based scheduling has been generally accepted as the norm. However, it is well established in the literature that PCTs are not always normally distributed and that their distribution and variability are affected by the distribution and variability of activity durations. This paper presents an automated risk quantification method that determines the best fit Probability Distribution Function (PDF) of PCTs. The algorithm is programmed in MATLAB and generates a set of simulation outputs obtained by systematically changing the probability distribution functions that define activities’ durations in a network and analyzes the effect of different distributions of activity durations on the distribution of the PCTs. The procedure is described and the findings are presented. This easy-to-use computerized tool improves the reliability of simulation-based scheduling by calculating the exact PDFs of activity durations, simulating the network, and calculating the exact PDF of PCTs. It also simplifies the tedious process involved in finding the PDFs of the many activity durations, and is a welcome replacement for the normality assumptions used by most simulation-based scheduling researchers.

This study developed new enzyme-specific superparamagnetic iron oxide nanoparticles (SPIONs) with potential as a multimodal probe in magnetic resonance (MR) imaging and optical imaging. For the MR/optical dual imaging, SPIONs were coated with near-infrared fluorescence dye (Cy5.5)-labeled hyaluronic acid (Cy5.5-HA), which could be readily degraded by hyaluronidase (HAdase). The presence of HA on the coated SPION was confirmed using FTIR, X-ray diffraction, and thermogravimetric analysis. Physicochemical analyses of Cy5.5-HA-coated SPIONs (Cy5.5-HA-SPIONs) demonstrated their higher colloidal stability and T2 relaxivity than bare SPIONs. When Cy5.5-HA-SPIONs were exposed to the MR instrument for the phantom test, the dark intensity of their T2-weighted image increased in a Fe concentration-dependent manner, suggesting potential as the MR probe. To examine their ability as the enzyme-sensitive optical probe, the fluorescent signals of Cy5.5-HA-SPIONs were measured in the absence or presence of HAdase. In the absence of HAdase, Cy5.5-HA-SPIONs showed a negligible fluorescent signal due to possible quenching between a SPION and fluorescence dye, and self-quenching effect of Cy5.5 molecules. On the other hand, in the presence of HAdase, the fluorescent signal of Cy5.5-HA-SPIONs increased dramatically as a function of the HAdase concentration, resulting from the degradation of the HA backbone. These results suggest that the Cy5.5-HA-SPION is useful as a multimodal nanoprobe for MR imaging and HAdase-sensitive optical imaging.

This paper reports the design, fabrication, modeling, and analysis of an electrochemical microactuator (ECM). The driving mechanism of the ECM is based on the reversible electrolysis process of water. The expansion and shrinkage of gas bubbles generated in a micro electrochemical chamber during a reversible electrolysis process can be used for actuation in microfluidic systems. The fluidic components of the ECM were fabricated on a glass substrate using UV lithography of SU-8. Two electrodes were used, with one Pt black (coated with platinum nanoparticles) as working and auxiliary electrode and the other Ag/AgCl coated as reference. The nano particles coated on the working electrode help to boost the surface-to-volume ratio of the electrode and to obtain higher operation frequency. Pulse electropotentials were supplied for active control of expansion and shrinkage of gas bubbles using reproducible electrochemical reactions. The theoretical volume change rate of gas bubbles was simulated as a function of time using the ideal gas law and compared with the measured volume change. The experimental results show the electrode coated with platinum nanoparticles helped to enhance the reversible electrolysis process significantly. The results also show that the dynamic model can be used to simulate the dynamic behaviors of the ECM actuator. The ECM can be used in microfluidic applications such as pumping or valves.

The coating thickness in hot-dip zinc galvanizing process is of practical importance in determining the quality of product, and its control is often done using the gas wiping through an air knife system. Such a gas wiping method causes a technical problem of splashing from the strip edge to have a harmful effect on the performance of the galvanizing process and the product quality. The present study aims at investigating the effectiveness of Coanda nozzle to reduce the strip splashing problem. A blow-down wind tunnel has been used to experimentally investigate the detailed flow field near the exit of Coanda nozzle and on the strip edge. A computational work has been performed with the help of a computational fluid dynamics method. The three-dimensional, compressible Navier-Stokes equations have been solved using a fully implicit finite volume scheme. The results obtained show that Coanda nozzle effectively reduces the splashing problem, leading to improvement of the whole galvanizing process.

Numerous studies have shown that the levels of matrix metalloproteinase (MMP)-2 and/or MMP-9 are associated with the invasive phenotypes of cancer cells. This study investigated the effects of caffeic acid phenethyl ester (CAPE), a chemopreventive phytochemical derived from honeybee propolis, on the invasive phenotype of SK-Hep1 human hepatocellular carcinoma cells (SK-Hep1 cells). CAPE effectively suppressed SK-Hep1 cell invasion in a dose-dependent manner. The constitutive expression of MMP-2 and MMP-9 in SK-Hep1 cells was almost completely abolished by treatment with 12.5 muM CAPE. CAPE also significantly inhibited nuclear factor kappa B (NF-kappaB) DNA-binding activity in SK-Hep1 cells. These results taken together suggest that CAPE exerts antimetastatic potential through inhibition of MMP-2 and MMP-9 expression, possibly by targeting NF-kappaB in hepatocellular carcinoma.