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We investigated the efficacy and safety of a trastuzumab biosimilar, Herzuma®, in combination with treatment of physician's choice (TPC) in patients with HER2+ metastatic breast cancer (MBC) who had failed at least two HER2 directed chemotherapies.

The need for students to learn science, technology, engineering, and mathematics (STEM) has increased steadily, while student motivation in this area continues to fall behind. We investigated the effects of science utility value intervention in increasing the science motivation (i.e., interest in science, appreciation of the role of science in future careers, and intention to engage in science-related activities) of Korean 5th and 6th graders. The usefulness of science for attaining the personal and communal goals inherent to various non-STEM careers was emphasized and internalized through classroom activities including postcard writing. At the end of the semester, students in the experimental group (n = 219) perceived greater personal and communal utility in science than those from the control group (n = 197). This enhanced perception of science utility led to greater interest, a higher likelihood of cognitively connecting science to future careers, and the willingness to engage in scientific activities.

Radiation-induced cavernous malformations (RICMs) are most commonly reported in young patients who have previously received radiotherapy. Here, we report a case of a patient with a germ cell tumor who was treated with whole brain radiotherapy (WBRT) and then incidentally found to have numerous RICMs. A 31-year-old male visited the hospital for a testicular mass. On examination, he was diagnosed with a mixed germ cell tumor with lung/brain metastases. The patient underwent a left orchiectomy and received 4 cycles of chemotherapy. He was then treated with WBRT for residual lesions in the brain and a wedge resection for the lung metastasis. Four years later, approximately 250-300 RICMs were incidentally observed in a follow-up brain image. Because the patient had not noticed any symptoms and the RICMs were small in size, he was not treated. To our knowledge, this is the first reported case of numerous (approximately 250-300) RICMs in a germ cell tumor patient after WBRT. Herein, we report details of this case and discuss the typical clinical features of RICM.

We aimed to investigate the prognostic influence of primary tumor site on the survival of patients with breast cancer.Data of 63,388 patients with primary breast cancer from the Korean Breast Cancer Registry were analyzed. Primary tumor sites were classified into 5 groups: upper outer quadrant, lower outer quadrant, upper inner quadrant, lower inner quadrant (LIQ), and central portion. We analyzed overall survival (OS) and breast cancer-specific survival (BCSS) according to primary tumor site.Central portion and LIQ showed lower survival rates regarding both OS and BCSS compared with the other 3 quadrants (all P .05) and hazard ratios were 1.267 (95% CI, 1.180-1.360, P .001) and 1.215 (95% CI, 1.097-1.345, P .001), respectively. Although central portion showed more unfavorable clinicopathologic features, LIQ showed more favorable features than the other 3 quadrants. Primary tumor site was a significant factor in univariate and multivariate analyses for OS and BCSS (all P .001). For lymph node-negative patients, LIQ showed a worse OS than the other primary tumor sites in the subgroup with no chemotherapy (P .001), but that effect disappeared in the subgroup with chemotherapy (P = .058).LIQ showed a worse prognosis despite having more favorable clinicopathologic features than other tumor locations and it was more prominent for lymph node-negative patients who received no chemotherapy. The hypothesis of possible hidden internal mammary node metastasis could be suggested to play a key role in LIQ lesions.

Organocatalytic manipulation of silicon reagents, which enables the efficient formation of carbon–carbon (C–C) or carbon–heteroatom (C–X) bonds have been attracting considerable attention since the past few decades. In several instances, surprisingly, water is a remarkably essential molecule to promote the desired transformation to achieve superb outcomes in terms of reaction rates, chemical yields, and stereoselectivities. From the catalytic amount to solvent quantity, water plays a crucial role in the asymmetric/non-asymmetric catalytic transformations such as aldol reactions, Michael addition reactions, Mannich reactions, α-alkylation reactions, and other related strategies. In the current review, we present a comprehensive report on the recent advances of small molecule catalyzed addition reactions of organosilicon reagents under “wet” condition (46 examples). Examples featuring in the synthesis of complex natural products are also discussed.

In this paper, Korean pathological voices are classified into signal type 1, 2, 3, or 4 to estimate perturbation parameters. Although the perturbation analysis can be applied to only type 1 and 2 signals, we recommend that the method should be carefully used to analyze the disordered database. Also the development of a suitable tool is essential for analysis of disordered voices such as signal type 3 and 4.

We analyzed the patterns of treatment and clinical outcomes of leptomeningeal metastasis (LM) in patients with non-small cell lung cancer (NSCLC) in the modern chemotherapy era.We retrospectively reviewed the data of NSCLC patients who were diagnosed with LM between 2003 and 2009 at Seoul National University Bundang Hospital.Of the 50 patients with cytologically proven LM, 25 were male (50%), 14 (28%) had an ECOG performance status (PS) ≥ 3, and the median age was 62.5 years (range, 34-81 years). The patients were diagnosed with LM after a median of 10.4 months (range, 0-86.8 months) from the initial diagnosis of metastatic NSCLC. LM was present in 11 patients at the time of initial diagnosis. The median overall survival (OS) after the diagnosis of LM was 4.3 months (95% CI, 1.5-6.7 months). Forty-eight patients (96%) received intrathecal chemotherapy and the cytological response rate was 52%. The median survival was 5.5 months in cytological responders and 1.4 months in non-responders (p=0.075). The median OS in patients with an ECOG PS of 1-2 was longer than patients with an ECOG PS of 3-4 (5.5 vs. 0.7 months, p0.001). Twenty-two patients (44%) received systemic cytotoxic chemotherapy or an EGFR tyrosine kinase inhibitor (TKI) after being diagnosed with LM. These patients had prolonged survival (11.5 vs. 1.4 months, p0.001), and in 14 patients (28%) who received an EGFR TKI, the median OS was 19.2 months. In subgroup of patients with an ECOG PS of 1-2, those who received further systemic chemotherapy had improved survival compared to patients who did not receive further chemotherapy (11.5 vs. 2.1 months, p0.001).NSCLC patients with LM exhibited diverse clinical outcomes rather than a uniformly poor prognosis. Systemic chemotherapy, especially EGFR TKIs in addition to intrathecal chemotherapy, might confer a survival benefit.

We fabricated nano-carbon (NC) doped MgB 2 bulks using an in situ process in order to improve the critical current density (J c ) under a high magnetic field and evaluated the correlated effects of the doped carbon content and sintering temperature on the phase formation, microstructure and critical properties. MgB 2―x C x bulks with x = 0 and 0.05 were fabricated by pressing the powder into pellets and sintering at 800 °C, 900 °C, or 1000 °C for 30 min. We observed that NC was an effective dopant for MgB 2 and that part of it was incorporated into the MgB 2 while the other part remained (undoped), which reduced the grain size. The actual C content was estimated to be 68-90% of the nominal content. The NC doped samples exhibited lower T c values and better J c (B) behavior than the undoped samples. The doped sample sintered at 900 °C showed the highest J c value due to its high doping level, small amount of second phase, and fine grains. On the other hand, the J c was decreased at a sintering temperature of 1000°C as a result of the formation of MgB 4 phase.

We fabricated ex situ MgB 2 wires using C-doped MgB 2 powder as a precursor in order to improve the core density of the wires and their C doping content. The C-doped powder was prepared with Mg, B, and nano carbon (NC) powders by the in situ technique and then MgB 2− x C x ( x = 0, 0.01, and 0.03) wires were fabricated by the ex situ technique using the powder-in-tube method. The phase formation, lattice change, and microstructure were characterized and correlated with the T c and J c variations. We observed that the ex situ wire had a higher core density than the in situ wire, however its morphology consisted of agglomerated particles, indicating that sintering and grain growth did not occur completely, even though the sintering was conducted at high temperature (1000 °C). As the C content increased, T c decreased, while the decrease of J c with increasing magnetic field became smaller. The J c of MgB 1.97 C 0.03 wire made by the ex situ technique was 3.34 kA/cm 2 at 6.6 T and 5 K which is comparable to that of the in situ wire (4.81 kA/cm 2 at 6.6 T and 5 K).

Rapid identification of bacterial pathogens is important for patient management and initiation of appropriate antibiotic therapy in the early stages of infection. Among the several techniques, capillary electrophoresis single-strand conformation polymorphism (CE-SSCP) analysis combined with small subunit rRNA gene-specific polymerase chain reaction (PCR) has come into the spotlight owing to its sensitivity, resolution, and reproducibility. Despite the advantages of the method, the design of PCR primers and optimization of multiplex PCR conditions remain to be studied so that as many pathogens as possible can be analyzed in a single run. Here we describe a novel two-step technique involving multiplex PCR pathogen detection by CE-SSCP analysis followed by singleplex PCR pathogen quantification by CE-SSCP. Specific PCR primers were designed for optimal separation of their products by CE-SSCP based on molecular weight. PCR conditions were then optimized for multiplex analysis of the targets. Subsequently, detected pathogens were quantified by PCR with specific primers. Eight clinically important strains were simultaneously identified under the optimized conditions. Each individual pathogen was then quantified at a level of sensitivity of tens of cells per milliliter. In conclusion, the two-step pathogen detection method based on CE-SSCP described here allows for sensitive detection of pathogens by multiplex PCR (first step) and quantification by specific PCR (second step). The results illustrate the potential of the method in clinical applications.

An electromagnetic sensor consisting of one exciter and three separated (triple) detectors is developed for both tracking the weld seam of a workpiece and controlling the sensor-to-workpiece distance (height) simultaneously. The left and right detectors are used to track the seam, while the fore and right detectors allow the sensor to determine the height and gap width by being coupled their outputs together. A series of experiments with the proposed sensor located above a mild steel plate containing a seam are carried out to examine the effectiveness of the sensor. The results revealed that the proposed sensor could fairly well track the desired seam and also well control the height to be constant even when the gap width of the seam varied. The gap width can be also determined during the seam tracking and height control by using the sensor outputs. As a consequence, these can provide the developed sensor with substantial improvement for industrial uses with respect to the previous electromagnetic sensors being used for the weld seam tracking.

A new fault detection and identification method based on kernel principal component analysis (PCA) is described. In the past, numerous PCA-based statistical process monitoring methods have been developed and applied to various chemical processes. However, these previous methods assume that the monitored process is linear, whereas most of the chemical reactions in chemical processes are nonlinear. For such nonlinear systems, PCA-based monitoring has proved inefficient and problematic, prompting the development of several nonlinear PCA methods. In this paper, we propose a new nonlinear PCA-based method that uses kernel functions, and we compare the proposed method with previous methods. A unified fault detection index is developed based on the energy approximation concept. In particular, a new approach to fault identification, which is a challenging problem in nonlinear PCA, is formulated based on a robust reconstruction error calculation. The proposed monitoring method was applied to two simple nonlinear processes and the simulated continuous stirred tank reactor (CSTR) process. The monitoring results confirm that the proposed methodology affords credible fault detection and identification.

Homolasonolide A and 10-desmethyllasonolide A are biologically less active than lasonolide A. The ethyl ester analogue of lasonolide A exhibited higher activity than the parent compound in some biological test.

Steel making is a representative power intensive industry, in which most of power is supplied by gas turbine generators transforming by-produced gases such as BFG, COG and LDG into electricity. The lack is usually supplemented by purchasing from regional electric power companies but, for stable and uninterrupted power supply, some steelworks (e.g. Kwangyang works of POSCO) are equipped with self-generators. Here the fuel is delivered according to a long-term plan, so that the monthly allocated amount must be exhausted. In this paper, an optimization technique based on the linear programming (LP) to reduce the overall power cost as well as a model for predicting the total load is presented.

Radial basis function networks (RBFNs) have been widely used for function approximation and pattern classification as an alternative to conventional artificial neural networks. In this paper, RBFN with local linear functions is developed and applied to mapping nonlinear functions and modeling air pollutant emission. This extended version of the traditional RBFN has a linear function of inputs as a connecting weight, which is functionally equivalent to the first-order Sugeno fuzzy model. There are three kinds of parameters determined through proper training algorithms: the centers and spreads of each radial basis function, and the connection weights. The extended RBFN (ERBFN) is trained by a hybrid learning algorithm, which uses an iterative nonlinear optimization technique to obtain the center and spread of each radial basis function and the least squares method to obtain the connection weights. To avoid capturing a local optimum, the nonlinear parameters are initialized using a modified K-means clustering method, which has cluster-merging characteristic so as to automatically determine the number of basis functions. The proposed ERBFN method was applied to the approximation of three different functional forms and to the modeling of a real process. The results confirm that the proposed methodology gives considerably better performance and shows faster learning in comparison to previous methods.

The ability to detect controller malfunctions is crucial in the monitoring of chemical process because malfunctioning controllers cause abnormal process operation, excess energy consuming and critical process upset. Especially, this paper is concerned to monitor the controller status in MIMO case. The proposed method is aimed to provide a practical basis on the earlier detection of degraded or malfunctioning controller. In this article, a new approach to controller performance monitoring in an online manner is presented that is based on multivariate statistical process control combined with time series analysis. Simulation case to distillation column is applied to demonstrate the suggested approach.

The dissolved oxygen (DO) concentration has been an important process parameter in the biological wastewater treatment system. A new strategy for designing a nonlinear model-based control is developed. The proposed controller can be incorporated directly with the nonlinear DO process model obtained by on-line parameter estimation method without any Iinearization or model reduction. Since the model-based nonlinear control incorporates the process disturbance and nonlinearity effectively, the suggested method can efficiently treat the operating condition. The simulation results show that the proposed control strategy outperforms the normal control strategy that uses a standard PID controller.

Sour water is mainly purified by steam stripping. In these days, steam stripper has been attracted considerably since effluent water quality and energy saving are getting more important. In this research, several guidelines which can improve stripping performance were proposed. Steady state simulation is used to find out the optimal operating condition. And dynamic simulation is performed to investigate the transient response on the disturbance and to solve control problem when NH 3 composition in feed increases. The proposed structure which uses an inter-cooler shows better control performance than the existing facilities.

An enhanced process identification method with biased-relay feedback is proposed for the design of PID controller This paper suggested a new theorem to get the transfer function of a process from the definition of Laplace transformation without any approximation. Based on this theorem, the process is identified as the second-order plus time delay (SOPTD) model with a least-squares method in a viewpoint of amplitude ratio and phase angle between the process and the SOPTD model. Since the proposed identification method does not approximate the relay and process outputs as sinusoidal signals, then the obtained SOPTD model can represent the process dynamics more accurately. A simulation study demonstrates its effectiveness and robustness to the measurement noise.

An enhanced PID control strategy is proposed for unstable processes. Ultimate data sets and the process gain estimated from an improved relay feedback method are used to identify unstable processes as unstable first-order plus time-delay models. We also suggest a simple control structure including an inner feedback loop and the corresponding tuning relations to manipulate unstable processes more efficiently and systematically. The proposed control method not only guarantees the simplicity and the easiness, but also shows much better control performance than previous control methods for unstable processes.

A new identification method using a proportional controller is proposed for autotic tuning of PID controller. A second-order plus time-delay (SOPTD) model is obtained by a least-squares method in the frequency domain. The suggested method can remove the restriction in applicability of previous methods so that it can be applied to any stable closed-loop response, regardless of the type of the transient such as overdamped, underdamped and inverse response. It is simple so that it does not need any complex techniques such as root finding or optimization method. With the obtained model parameters, the three parameters of PID controller can be calculated from the integral of the time-weighted absolute value of the error (ITAE) tuning rule on-line. Simulation study shows the robustness with respect to measurement noise and disturbance at the identification stage.

In the presence of static load disturbance, a relay auto-tuning experiment shows significant errors in estimating the ultimate gain and period. This paper shows how to overcome the problem without any information on the static gain of the process and how to obtain process gain from one relay experiment.