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The focus on STEM has centered on knowledge use across multiple disciplines. However, there currently exists limited understanding of the relationship between the cognitive practices utilized across these disciplines as a function of performance on standardized assessments. Focusing on science and mathematics, we investigated the direct and indirect relationships between science and mathematics reasoning practices. The TIMSS 2011 cognitive practices were adopted to establish a hypothesized model representing these relationships. We employed the generalized DINA (deterministic inputs, noisy “and” gate), confirmatory factor analysis (CFA), and structural equation modeling (SEM) to 2287 fourth-graders’ responses to standardized mathematics and science assessments. The findings show positive relationships among science reasoning, mathematics reasoning, and mathematics applying. However, we also found a significant indirect effect from science reasoning to mathematics reasoning through mathematics applying. This result calls for a need to shift the focus of interdisciplinary efforts to emphasize cognitive practices that students use in learning mathematics and science as suggested in the Next Generation Science Standards and the Common Core State Standards for Mathematics.

The recent expansion of the internet network and rapid advancements in information and communication technology are expected to lead to a significant increase in power consumption and the number of data centers. However, these data centers consume a considerable amount of electric power all year round, regardless of working days or holidays, thus, energy saving at these facilities has become essential. A disproportionate level of power consumption is concentrated in computer rooms because air conditioners in these rooms are required to operate throughout the year to maintain a constant indoor environment for stable operation of computer equipment with high-heat release densities. Considerable energy-saving potential is expected in such computer rooms, which consume high levels of energy, if an outdoor air-cooling system and air conditioners are installed. These systems can reduce the indoor space temperature by introducing a relatively low outdoor air temperature. Therefore, we studied the energy-saving effect of introducing an outdoor air-cooling system in a computer room with a disorganized arrangement of servers and an inadequate air conditioning system in a research complex in Korea. The findings of this study confirmed that annual energy savings of up to approximately 40% can be achieved.

Objective The present study aimed to explore how the patterns of interaction between stress and positive resources differ according to the severity of depression and which resources play the most important role among the various positive resources.Methods The study included 1,806 people who had visited a health screening center for a mental health check-up to evaluate the levels of perceived stress, positive resources, and depressive symptoms. The participants were divided into a depressive group (n=1,642, mean age 50.60, female 68%) and a non-depressive group (n=164, mean age 48.42, female 66.6%). We conducted hierarchical regression analyses and simple slope analyses to examine the interaction between perceived stress and positive resources.Results The interaction between perceived stress and optimism was significantly associated with depression in non-depressive groups. In depressive groups, the interactions between five types of positive resources (optimism, purpose in life, self-control, social support and care) and perceived stress were all significantly related to depression.Conclusion Interventions that promote optimism can be helpful for preventing inevitable stress from leading to depression. A deficiency in positive resources may be a factor in aggravating depression in stressful situations for people reporting moderate to severe depressive symptoms.

When the thermionic electron gun of the klystron operates, the structure around the cathode is subjected to thermal deformation due to the high operating temperature of the cathode. A thermal deformation analysis of the existing electron gun with ‘cold’ dimensions (dimension on fabrication) was done using the ANSYS code to get the ‘hot’ dimensions of the electron gun on operation. After that, the optics of the emitted electron beam were simulated using two codes (EGUN and CST-PS) for the two cases of the ‘cold’ dimension and the ‘hot’ dimension. We compared the beam trajectories of the above two cases to investigate the change in the physical quantities, which would have a strong effect on the klystron performance due to the thermal deformation. The thermal deformation was found to cause a perveance change as large as 15%. The scalloping behavior was also investigated with an applied magnetic field for the two cases of cold and hot dimensions.

We proposed and demonstrated a novel method to package liquid-core hexagonal photonic crystal fibers (PCFs) by utilizing a hollow optical fiber (HOF) not only as a liquid delivery tube but also as a light launching pedestal. Compact all-fiber packaging with single mode fiber input and output was experimentally achieved. Various configurations of liquid core PCFs were demonstrated by controlling the inner diameter of HOF and offsets. Based on numerical analyses and light launching experiments, we confirmed that this method could substantially enhance the light–liquid interaction efficiency, structurally prevent liquid evaporation within PCF, and providing a new versatile liquid core PCF device platform.

One of the many causes of cancer is a dysfunction of the DNA damage repair (DDR) pathway. Cancers with alterations in homologous recombination (HR) genes are known to be increased the sensitivity of PARP inhibitors and genomic instability. Besides, cancers with alterations in other DDR genes like mismatch repair (MMR), have been recently reported to have similar features. Furthermore, some studies suggested that hypermutated cancers, such as microsatellite instability-high (MSI-H) or tumor mutational burden (TMB) high, have DDR gene alterations. Nevertheless, many studies still have focused on HR-related gene alteration as a predictor of olaparib. Here, we aim to determine if the DDR gene alteration and genomic instability markers can predict olaparib efficacy in 49 gastric cancer cell lines. First, we profiled the genomic status of 48 DDR genes, MSI status, and TMB using targeted sequencing (524 genes). BRCA1, RAD51C, and MLH1 methylation were detected by bisulfite sequencing. If cell lines had the deleterious mutation, homozygous deletion, or methylation in DDR genes, it was categorized as an alteration group. To determine the efficacy of olaparib, cell lines were treated with olaparib for 5 days and assessed by CCK-8 assay. IC50 values were determined by the CalcuSyn software and cell lines were classified as a sensitive group when the IC50 was less than 10µM. MMR-related and PARP1 protein expression was determined by western blot. As a result, 17 cell lines had the alteration in one or more of the 18 DDR-related genes. In our cell line panel, the expression of PARP1 protein was varied, and 12 cell lines were sensitive to olaparib. DDR alteration group was more sensitive to olaparib than the DDR wild type group (median of IC50 = 14.08µM vs > 20µM, p = 0.034). In detail, cell lines with alterations in the HR and MMR were significantly sensitive among the subtype of DDR pathways (p = 0.011, p = 0.009). TMB was widely distributed among the GC cell lines (range = 4.36 to 21.80, median = 10.90), and the DDR alteration group had higher TMB than DDR wild type group (median = 11.63 vs 10.90, p = 0.029). Interestingly, the olaparib sensitive group had higher TMB than the resistant group (median = 15.3 vs 10.9, p < 0.0001). Four cell lines (SNU-1, SNU-638, IM95m, and NUGC-3) were MSI-H, and all of them were no MLH1 protein expression. MSI-H cell lines had significantly higher TMB than other cell lines (median=19.3, p < 0.0001). Three MSI-H cell lines were sensitive to olaparib, but NUGC-3 with the lowest TMB (13.8) among MSI-H cell lines was resistant. In our result, the olaparib sensitive group had the alteration in DDR genes and high TMB. MSI-H cell lines were sensitive to olaparib when it had high TMB. MSI status and TMB could predict olaparib sensitivity in gastric cancer as well as DDR gene alterations. Citation Format: Jihyun Hwang, Woo sun Kwon, Juin Park, Hyun Joo Bae, Inhye Jeong, Sun Kyoung Kang, Tae Soo Kim, Jingmin Che, Hyun Cheol Chung, Sun Young Rha. Evaluation of DNA damage repair gene alterations, microsatellite instability status, and tumor mutational burden as predictive biomarkers of olaparib sensitivity in gastric cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2055.

HER2 is amplified in 7% to 20% of gastric cancer (GC) and is associated with poor clinical outcome. Trastuzumab, HER2-targeting antibody, has already been successfully employed for the treatment of HER2 amplified metastatic GC patients. However, most GC patients who achieved an initial response to the trastuzumab-based regimen developed resistance within 1 year after treatment. In this study, we aimed to investigate the efficacy and biological mechanism of trastuzumab deruxtecan (T-DXd) for overcoming trastuzumab resistance in HER2 amplified GC cell lines. We established four trastuzumab resistant cell lines from HER2 amplified GC cell lines by trastuzumab dose-escalation treatment; YCC-33TR, YCC-38TR, NCI-N87TR, and SNU-216TR. Next, we compared the anti-tumor efficacy of trastuzumab and T-DXd (Daiichi Sankyo, Japan), a HER2-targeting antibody-drug conjugate (ADC), in parental and trastuzumab resistant cell lines. Drug sensitivities were determined by the inhibition rates (IR) at 100μg/ml using cell viability assay. Both in baseline and in post-treatment drug responses, expression levels of proteins such as HER2, Erk, Akt, H2A.X and cPARP were detected by western blotting. The parental cell lines were sensitive to trastuzumab, while four trastuzumab resistant (TR) cell lines demonstrated significant resistance to trastuzumab (p In summary, the established trastuzumab resistant cell lines retained high HER2 expression, and both HER2 amplified parental and trastuzumab resistant cell lines were sensitive to T-DXd. Our data indicated that T-DXd may have a potential therapeutic effect to overcome trastuzumab resistance in GC. Citation Format: Juin Park, Inhye Jeong, Sun Kyoung Kang, Seo Young Yu, Woo Sun Kwon, Tae Soo Kim, Jihyun Hwang, Hyun Cheol Chung, Sun Young Rha. Overcoming trastuzumab resistance using trastuzumab deruxtecan (T-DXd), a HER2 targeting antibody drug conjugate, in HER2 amplified gastric cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1090.

In order to suppress beam losses and radiations in high-power klystrons, the electron beam should be desinged to have the scalloping (i.e., the radial oscillation of beam envelope) as small as possible. This is done by matching the focusing field profile with beam trajectories (which are usually convergent). In this article, we report on the beam-matching simulations using a newly developed matching procedure with various beam radii and design solenoid magnets of S-band klystrons at Pohang Accelerator Laboratory (PAL).

Background The objective of this study was to determine whether severity and severity change of coexisting psychiatric symptoms might affect change of complicated grief (CG) regarding the Sewol ferry disaster. Methods Data from a cross-sectional survey were obtained 18 months (Time 1) and 30 months (Time 2) after the disaster. We ascertained sociodemographic variables and variables obtained from self-reporting questionnaires (i.e., CG, depression, anxiety, post-traumatic stress disorder [PTSD], insomnia, embitterment, and suicidal risk) among 56 bereaved family members. Results Severity of other psychiatric symptoms at Time 1 had no effect on change of CG at Time 2. However, changes in severity of PTSD over a year affected change of CG. Conclusion It is important to evaluate changes in severity of PTSD and its treatment during management of CG, especially when it involves bereaved families experiencing a traumatic accident., Graphical Abstract

Background: The prevalence of microsatellite instability-high/mismatch repair-deficient (MSI-H/dMMR) and Lynch syndrome with germline MMR mutations in gastric cancer (GC), are 5% and 1.6%, respectively. According to TCGA data, BRCA mutations, one of DNA Damage Response (DDR) pathway genes, occur in about 10% of GC (BRCA1 2.7%, BRCA2 7%), but the incidence is increased in MSI-H GC (BRCA1 16%, BRCA2 34%). Our study focused on integrative analysis of germline and somatic genetic alterations according to dMMR status for new therapeutic strategy. Methods: Retrospective comparison analysis of advanced gastric cancer patients between 20 dMMR and 48 proficient MMR (pMMR) was performed using targeted next-generation sequencing (NGS) for somatic genetic alterations and Global Screening Array (Illumina©) to detect germline alterations. PD-L1 expression using immunohistochemistry 22C3 pharmDx was evaluated. TMB was calculated based on somatic nonsynonymous missense mutations and DDR genes were compared. DNA pyrosequencing was used to determine promoter methylation status of MLH1 gene. Results: dMMR was associated with higher TMB (median 64 mut/Mb, IQR 54 -73 vs. 42 mut/Mb, IQR 34 - 50, P 50 mut/Mb (n=29, p Citation Format: Garden Lee, Jihyun Hwang, Sejung Park, Woo Sun Kwon, Jinseul Park, Jii Bum Lee, Choong-kun Lee, Hyun Cheol Chung, Sun Young Rha. New therapeutic strategy by integrative analysis of germline, somatic genetic alterations and tumor mutational burden (TMB) in deficient mismatch repair (dMMR) gastric cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr C106. doi:10.1158/1535-7163.TARG-19-C106

We report a new efficient light guidance along a liquid core using an open V-groove. Guiding properties were analyzed using finite element method in terms of the single mode guidance condition, and the corresponding modal birefringence. We experimentally demonstrated a silica V-groove fiber with an opening angle of 40°, which was spliced to single mode fibers at both ends. A liquid with the refractive index of 1.455 was filled to serve as a core along a maximum length of 47cm. We confirmed the single mode guidance and birefringence consistent to theory, which will enable polarimetric liquid sensing.

The objective of this study was to investigate the relationship between serum lipid concentrations and PTSD symptoms in the bereaved after a traumatic familial loss. Eighteen months after the Sewol ferry disaster, 107 subjects who experienced traumatic losses as a result of the accident completed a mental and medical survey as well as laboratory tests for lipid profiles. At 30 months after the trauma, a total of 64 individuals completed a follow-up psychometric survey and biochemical measurements. We performed multiple linear regression analyses, examining the association between PTSD symptoms and lipid profiles. Other potential influences on lipid profiles such as metabolic risk factors, demographic risk factors, and underlying medical history were accounted for. Participants reporting clinically significant PTSD symptoms exhibited lower serum HDL-C levels than those without PTSD symptoms. In addition, we found that the severity of PTSD symptoms and sex could explain the changes in lipid profiles independently of other possible risk factors of changes. The results of this study suggest that PTSD symptoms may contribute to an increased risk for developing metabolic syndrome via detrimental changes in lipid concentrations. Routine screening and multidisciplinary management to prevent metabolic syndrome in individuals who experience traumatic losses would therefore be valuable.

Liquids of a wide range of refractive indices were atomized by a guided IR laser along a tapered hollow optical fiber with a nanometer hole. Liquid droplet delivery by the light field was also experimentally investigated.

We propose a new technique to make a periodic structure using liquid and explain its theoretical principle. By controlling the pitch of grating, the delta index and the properties of inner surface to regulate contact angle, we could obtain the possibility of using as optical device which is the long period fiber grating. When the water based DNA was applied to this structure, we observed that the temperature dependent intensity of wavelength did switching at 896nm.

A prototype 5-GHz 500-kW CW klystron (model E3762 provided by Toshiba Electron Tubes & Devices Co. Ltd.) has been operating as the RF source for the lower hybrid current drive (LHCD) system in the KSTAR tokamak. A cavity design study is being carried out with a simulation code based on the main klystron’s operation parameters in order to investigate how the efficiency of the 5-GHz 500-kW CW klystron prototype can be enhanced. This is being done by simulating the klystron’s performances for various cavity parameters, including the number of cavities, the inter-cavity distance, and the cavity’s tuning frequencies. The simulation has been done with the FCI (field charge interaction) code aided by a matlab script for scanning input parameters. The initial set of scan parameters was obtained by benchmarking the E3762 klystron, and we are able to obtain optimized design parameters for a cavity system with better efficiency by adopting a multi-cell output cavity. However, the multi-cell output cavity is prone to self-oscillations due to the prolonged (several half RF periods) beam-field interaction along its multiple gaps. We have checked the feasibility of the optimization by evaluating the stability of the output cavity system. The stability is given by the ratio of a beam-loading conductance to the circuit conductance.

Long-period fiber gratings (LPFGs) are useful for environmental sensing under conditions of high corrosiveness and electromagnetic interference. Most LPFGs are fabricated by coherent or high-power UV illumination of an optical fiber under an amplitude mask, resulting in narrow and environmentally-dependent band rejection. We present a hybrid LPFG waveguide fabricated without an amplitude mask through polymer self-assembly under low-power incoherent UV illumination, which demonstrates high-temperature sensitivity in its transmission spectrum compared to LPFG sensors based purely on silica waveguides. A sensitivity of 1.5 nm °C -1 is obtained experimentally for attenuation near 1180 nm, and a sensitivity of 4.5 nm °C -1 with a low random error was obtained with a composite of attenuation bands. Finite element method simulations and coupling mode theory reveal this to be due to a thermo-optic coefficient one order of magnitude greater than that of fused silica. The device has potential for a simple and inexpensive transmission intensity based temperature sensor consisting of an infrared light source, the LPFG, a bandpass filter, and a photodiode.

We report development of a new kind of micro-optical waveguide based on liquid core in a V-groove glass and air cladding and a similar finite element method was constructed to investigate the guiding properties such as mode distribution and modal birefringence. Through the detailed modeling, we investigate the role of each parameter such as, refractive index of core and diameter of core of V-groove structure. This work demonstrates numerically and experimentally high birefringence in this optical waveguide and different aspects of the fiber properties related to the fundamental mode and fiber birefringence are revealed. As a result, wave-guide with large birefringence is identified for opening angle of 40 degree and refractive index of 1.472.

This study confirms possibility of the application of liquid fiber lasers and optical amplifiers with fiber lasers integrated into liquid as a gain medium with quantum dots.

Deoxyribonucleic acid (DNA) has been a remarkable material in the development of optoelectronic devices for granted these days. In this research, we report on an optical phenomenon of DNA structures grown by a self-assembly process. Discrete 2D nanocrystal structures of DNA were prepared on a light-guiding substrate. The high evanescent field interaction between the guided light supplied via D-shaped optical fiber and DNA monolayers enabled the systematic investigating of the optical properties of DNA nanocrystal structures. In particular, light guided down the fiber and received by an optical spectrum analyzer enabled spectral analysis, while morphology studies of the self-assembly DNA were performed by atomic force microscopy.

We report a unique technique to generate a liquid periodic structure whose unit volume is as low as a few hundred femto-liter. Liquids such as water, toluene and ethanol were filled in a hollow optical fiber (hole diameter of 8 and 13μm), which were locally heated by a traversing miniature electric furnace. The periods between droplets could be varied flexibly in the range from 14 to 100μm and the volume of individual droplet was in the range from 112 to 845 femto-liter. We also fabricated the periodic liquid droplets with quantum dots, whose fluorescence was successfully measured in each droplet. These periodic liquid droplets could serve as flexible liquid long period fiber grating for the hollow optical fiber, which can be further applied in various mechanical and bio-chemical sensors

We report the development of a new kind of micro-optical waveguide based on a liquid core in a V-groove glass and air cladding. This work demonstrates numerically and experimentally high birefringence in this optical waveguide.

The purpose of this study is to examine the effects of object building activities in Second Life on playerspsila spatial reasoning and to explore the relationships between learnerspsila information perceiving styles and spatial reasoning. The participants of this study included 70 undergraduate students who were taking the class dasiaNew Media in Educationpsila. For this study, Kolbpsilas learning style inventory was administered to the participants in advance of activities in Second Life. Also they were given instructions on building objects related to spatial reasoning activities (e.g., analysis and synthesis, deductive reasoning, development and application of visualization methods, systematic approach, and transformation) in Second Life. As a result, it was discovered that Second Life activities are more effective for the abstract conceptualization group than for the concrete experience group. This implies that activities provided in Second Life were more positively effective to abstract conceptualization learners on their information processing such as spatial reasoning.