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Behavior coding is used to detect issues in questionnaires by flagging interactions between survey respondents and interviewers when their interactions deviate from standardized interviewing. It has become a popular method for evaluating survey questionnaire quality and has been used mostly in Western countries, with little research being done in Asia. However, because of its dependence on overt behaviors observed during the coding, it was hypothesized that it might not be as effective in a country where different communicative norms are present. We conducted an experiment in Korea using two sets of survey questionnaires with embedded problematic questions in the experimental group to investigate the validity of behavior coding as reference to the control group. Using 200 audio recordings from a telephone survey, we investigated whether behavior-coded data were helpful in identifying embedded flaws. The results indicated behavior coding in Korean surveys may not be as effective as in Western countries.

When recruiting respondents for cognitive interviews testing translated survey questionnaires, researchers often recommend interviewing monolingual non-English speakers because they are the likely users of the translations. However, these individuals are hard to recruit, and there is no standard definition of monolingual. Using cognitive interview data collected from pretesting of Chinese and Korean translations of the American Community Survey Language Assistance Guide, we investigated whether there were differences in respondents' understanding of survey questions according to their level of English proficiency and if such differences remained after considering demographic characteristics. We found that the types of issues reported by monolingual speakers and partially bilingual speakers were similar and that differences seemed to be driven by different demographic characteristics and not necessarily by language proficiency. Our findings suggest the value of evaluating translated questionnaires with individuals having diverse demographic characteristics and recruiting both monolingual speakers and partially bilingual speakers as research participants.

Featured Application: The results of this paper can be instrumental in establishing insulation material management standards for determining the stable operation condition of XLPE cables in the future. Cross-linked polyethylene (XLPE) cable is a representative power transmission cable. XLPE has excellent mechanical properties, chemical and heat resistance, and insulation. However, XLPE insulation deteriorates during operation due to electrical, mechanical, and thermal stresses. Among these, thermal stress is a major factor and reduces insulation properties due to a change in molecular structure. Therefore, XLPE characteristic evaluation by heat exposure is essential for power cable condition evaluation. Herein, deteriorated XLPE samples were characterized by tensile strength, X-ray diffraction, Fourier-transform infrared spectroscopy, differential scanning calorimetry, and ultraviolet-visible spectroscopy after exposure to various temperatures and durations. Comparing the tensile strength with other analysis results yielded correlations. Each characteristic showed a linear relationship. The correlation between tensile strength and carbonyl index was the strongest, and the coefficient of determination, R2, was 0.9299. Therefore, these results will provide important information on chemical properties when establishing operational management standards for XLPE insulators in the future. [ABSTRACT FROM AUTHOR]

Furfural is an intermediary and aldehyde compound degraded from paper insulation, which is used with liquid fluid in power transformers. It can be utilized as an important indicator to evaluate the degradation degree of the paper insulation and the condition of transformers to predict their lifetime. However, the conventional methods are inevitably inconvenient as they require additional derivatization with hazardous agents and time-consuming chromatographic separation and processes. In this work, a facile and green analysis method for the determination of furfural concentration in the insulating fluid of operating power transformers was developed. As furfural was selectively extracted from the insulting fluid by deionized water, the aqueous solution could be directly subjected to a UV spectral analysis without any derivatization using hazardous agents or hindrance of the fluid in the UV spectrum. The results showed that the spectral method could obtain a favorable linear relationship between the concentration of furfural and its characteristic absorbance at 280 nm (λ max). The limit of detection (LOD) was below 0.1 ppm, which is a sufficient detection level to evaluate the condition of the insulating fluid. Furthermore, the method was compared with the conventional HPLC and colorimetric analyses, revealing satisfactory accuracy and verification of the results. It is possible to measure the furfural concentration in situ using a portable UV-spectrometer at a single wavelength, 280 nm, after simple extraction in the field. This approach offers a novel and green analytical method to quantitatively determine the aromatic furan compounds in a power transformer's insulating fluid in place without the use of an organic extraction solvent or hazardous reagents for derivatization and analysis. [ABSTRACT FROM AUTHOR]

Background: Polycystic kidney disease (PKD) is a hereditary disease characterized by cyst formation in the kidneys bilaterally. It has been observed that semaphorin-3C (SEMA3C) is overexpressed in polycystic kidney epithelial cells. It is hypothesized that upregulated SEMA3C would contribute to survival of polycystic kidney epithelial cells. Furthermore, as the kidney is a highly vascularized organ, the secreted SEMA3C from PKD epithelial cells will affect glomerular endothelial cells (GECs) in a paracrine manner.Methods: To evaluate the effect of SEMA3C on renal cells, siSEMA3C-treated PKD epithelial cells were used for further analysis, and GECs were exposed to recombinant SEMA3C (rSEMA3C). Also, co-culture and treatment of conditioned media were employed to confirm whether PKD epithelial cells could influence on GECs via SEMA3C secretion.Results: SEMA3C knockdown reduced proliferation of PKD epithelial cells. In case of GECs, exposure to rSEMA3C decreased angiogenesis, which resulted from suppressed migratory ability not cell proliferation.Conclusions: This study indicates that SEMA3C is the aggravating factor in PKD. Thus, it is proposed that targeting SEMA3C can be effective to mitigate PKD. [ABSTRACT FROM AUTHOR]

Changes in microcirculation are believed to perform an important role after cardiac arrest. In particular, rheological changes in red blood cells (RBCs) have been observed during and after ischemic-reperfusion injury. Employing three-dimensional laser interferometric microscopy, we investigated three-dimensional shapes and deformability of RBCs during and after asphyxial cardiac arrest in rats at the individual cell level. Rat cardiac arrest was induced by asphyxia. Five rats were maintained for 7 min of no-flow time, and then, cardiopulmonary resuscitation (CPR) was started. Blood samples were obtained before cardiac arrest, during CPR, and 60 min after return of spontaneous circulation (ROSC). Quantitative phase imaging (QPI) techniques based on laser interferometry were used to measure the three-dimensional refractive index (RI) tomograms of the RBC, from which structural and biochemical properties were retrieved. Dynamic membrane fluctuations in the cell membrane were also quantitatively and sensitively measured in order to investigate cell deformability. Mean corpuscular hemoglobin, mean cell volume, mean corpuscular hemoglobin concentration, and red blood cell distribution width remained unchanged during CPR and after ROSC compared with those before cardiac arrest. QPI results revealed that RBC membrane fluctuations, sphericity, and surface area did not change significantly during CPR or after ROSC compared with initial values. In conclusion, no three-dimensional shapes and cell deformability changes in RBCs were detected. [ABSTRACT FROM AUTHOR]

This study aims to empirically investigate whether cognitive interviewing is effective as a pretesting method for detecting problems in translated survey questionnaires as in the English language source questionnaire. The validity of non-English cognitive interviews is of concern among researchers because the cognitive interviewing technique was developed based on the communicative norms of Western cultures where directness and openness in expressing one’s opinion is encouraged. However, different communicative norms are present in Asian languages and cultures. To date, little research has been conducted on this topic. Using qualitative and quantitative analysis, we compared survey question problems identified through the cognitive interviews conducted in English and in Korean and found that Korean cognitive interviewing was indeed effective for detecting problematic survey questions. [ABSTRACT FROM AUTHOR]

Previous studies have found monolinguals and bilinguals use different areas of the brain when solving problems, while bilinguals manifest a cognitive system with the ability to attend to more relevant information while ignoring distractions (Bialystok 2007; Hernandez and Bates 2001). Since the mental process that monolinguals experience when answering survey questions differs from that of bilinguals, they likely encounter different problems in understanding the meaning of questions even in their native language. Therefore, for cognitive interviews aimed at improving the quality of translated questionnaires targeting monolingual non-English speakers, it is crucial to conduct interviews with such respondents to elicit relevant information. However, there has been no standardized tool for identifying these speakers. By using different definitions of monolingual speakers: (1) based on self-rated English reading, (2) based on self-rated speaking, and (3) based on both, we investigate how similar or different these groups are by comparing their demographic characteristics. [ABSTRACT FROM PUBLISHER]

Few empirical studies have evaluated the efficiency of recruitment methods to recruit non- English-speaking research participants. We attempt to fill this research gap by conducting a systematic evaluation using recruitment data from a large cognitive testing study that pretested the translations of the American Community Survey. In our study we contacted 1,084 Chinese and Korean speakers to identify those who spoke little or no English. We measured the efficiency of the recruitment methods (newspaper advertisements, flyers, online communication, and word of mouth) using four criteria: time spent, outreach capacity, screener completion, and eligibility rate. We also examined differences in recruitment efficiencies by recruiters and sublanguage groups. Among the recruitment methods examined, newspaper advertisements were most efficient in reaching a larger number of Asians while using the least amount of recruiters' time. For recruiting non-English speakers, word of mouth by recruiters with strong ties to the ethnic community worked best. [ABSTRACT FROM AUTHOR]

A cellular-level study of the pathophysiology is crucial for understanding the mechanisms behind human diseases. Recent advances in quantitative phase imaging (QPI) techniques show promises for the cellular-level understanding of the pathophysiology of diseases. To provide important insight on how the QPI techniques potentially improve the study of cell pathophysiology, here we present the principles of QPI and highlight some of the recent applications of QPI ranging from cell homeostasis to infectious diseases and cancer. [ABSTRACT FROM AUTHOR]

Several low- or non-FcR binding anti-human CD3 monoclonal antibodies have been under investigation for the treatment of autoimmune diseases. To model the mechanism of action of these anti-human CD3 mAbs in the murine system, an Fc-modified anti-mouse CD3 antibody (N297A) was generated. N297A exhibited similar biological effects as Fc-modified anti-human CD3 antibodies including rapid, reversible reduction in peripheral leukocyte numbers, differential modulation of activated versus resting T cells, and reduced levels of induced cytokine release compared to the non-Fc-modified parent antibody. In an in vivo model of colitis induced by adoptive transfer of IL-10-deficient cells, administration of N297A significantly reduced body weight loss. As N297A shared many functional characteristics of non-FcR binding anti-human CD3 mAbs both in vitro and in vivo, it provides a means to model the mechanisms of action of Fc-modified anti-human CD3 antibodies in mouse. [ABSTRACT FROM AUTHOR]

Babesia microti causes 'emergency' human babesiosis. However, little is known about the alterations in B. microti invaded red blood cells (Bm-RBCs) at the individual cell level. Through quantitative phase imaging techniques based on laser interferometry, we present the simultaneous measurements of structural, chemical, and mechanical modifications in individual mouse Bm-RBCs. 3-D refractive index maps of individual RBCs and in situ parasite vacuoles are imaged, from which total contents and concentration of dry mass are also precisely quantified. In addition, we examine the dynamic membrane fluctuation of Bm-RBCs, which provide information on cell membrane deformability. [ABSTRACT FROM AUTHOR]

The article focuses on the use of confocal microscopy in observing the three-dimensional translational and rotational motion of a cluster of fluorescently labeled colloidal particles. As stated, by showing both translational and rotational displacements, colloidal clusters serve as tracers of local dynamics. It further informs that fluorescently labeled particles can be directly observed through confocal microscopy.

The present study compares L2 learning motivation between commonly taught language (CTL) and less commonly taught language (LCTL) learners in university settings in South Korea, mainly focusing on Dörnyei's (2005, 2009) L2 Motivational Self System. A total of 1296 Korean college students, including 638 CTL and 658 LCTL learners, participated in a questionnaire survey, and the main analysis method was a multi-group structural equation model (SEM). The results support the validity of Dörnyei's L2 Motivational Self System in comparing and explaining Korean CTL and LCTL learners' motivation. For both CTL and LCTL groups, L2 learning attitude appeared as the most influential factor influencing learners' intended effort, followed by the ideal L2 self. The impact of the ought-to L2 self on L2 learning effort was relatively low. Two variables, international posture and competitiveness, which were assumed to be influenced by the Korean socio-educational context, were also observed in the SEM analysis. More specifically, their impact on the ideal L2 self, L2 learning attitude, and the ought-to L2 self were compared between CTL and LCTL groups. This comparison revealed the differing patterns of relationships among the variables between the two groups. This study provides pedagogical implications based on these key findings. [ABSTRACT FROM AUTHOR]

Evoked compound action potentials (ECAPs) measured during epidural spinal cord stimulation (SCS) can help elucidate fundamental mechanisms for the treatment of pain and inform closed-loop control of SCS. Previous studies have used ECAPs to characterize neural responses to various neuromodulation therapies and have demonstrated that ECAPs are highly prone to multiple sources of artifact, including post-stimulus pulse capacitive artifact, electromyography (EMG) bleed-through, and motion artifact. However, a thorough characterization has yet to be performed for how these sources of artifact may contaminate recordings within the temporal window commonly used to determine activation of A-beta fibers in a large animal model.
We characterized sources of artifacts that can contaminate the recording of ECAPs in an epidural SCS swine model using the Abbott Octrode™ lead. Spinal ECAP recordings can be contaminated by capacitive artifact, short latency EMG from nearby muscles of the back, and motion artifact. The capacitive artifact can appear nearly identical in duration and waveshape to evoked A-beta responses. EMG bleed-through can have phase shifts across the electrode array, similar to the phase shift anticipated by propagation of an evoked A-beta fiber response. The short latency EMG is often evident at currents similar to those needed to activate A-beta fibers associated with the treatment of pain. Changes in CSF between the cord and dura, and motion induced during breathing created a cyclic oscillation in all evoked components of recorded ECAPs. 
Controls must be implemented to separate neural signal from sources of artifact in SCS ECAPs. We suggest experimental procedures and reporting requirements necessary to disambiguate underlying neural response from these confounds. These data are important to better understand the framework for recorded ESRs, with components such as ECAPs, EMG, and artifacts, and have important implications for closed-loop control algorithms to account for transient motion such as postural changes and cough., (Creative Commons Attribution license.)

We present trace gas vertical profiles observed by instruments on the NASA DC-8 and at a ground site during the Korea-US air quality study (KORUS) field campaign in May to June 2016. We focus on the region near the Seoul metropolitan area and its surroundings where both anthropogenic and natural emission sources play an important role in local photochemistry. Integrating ground and airborne observations is the major research goal of many atmospheric chemistry field campaigns. Although airborne platforms typically aim to sample from near surface to the free troposphere, it is difficult to fly very close to the surface especially in environments with complex terrain or a populated area. A detailed analysis integrating ground and airborne observations associated with specific concentration footprints indicates that reactive trace gases are quickly oxidized below an altitude of 700 m. The total OH reactivity profile has a rapid decay in the lower part of troposphere from surface to the lowest altitude (700 m) sampled by the NASA DC-8. The decay rate is close to that of very reactive biogenic volatile organic compounds such as monoterpenes. Therefore, we argue that photochemical processes in the bottom of the boundary layer, below the typical altitude of aircraft sampling, should be thoroughly investigated to properly assess ozone and secondary aerosol formation.

RIPK1, RIPK3, ZBP1 and TRIF, the four mammalian proteins harboring RIP homotypic interaction motif (RHIM) domains, are key components of inflammatory signaling and programmed cell death. RHIM-domain protein activation is mediated by their oligomerization; however, mechanisms that promote a return to homeostasis remain unknown. Here we show that autophagy is critical for the turnover of all RHIM-domain proteins. Macrophages lacking the autophagy gene Atg16l1 accumulated highly insoluble forms of RIPK1, RIPK3, TRIF and ZBP1. Defective autophagy enhanced necroptosis by Tumor necrosis factor (TNF) and Toll-like receptor (TLR) ligands. TNF-mediated necroptosis was mediated by RIPK1 kinase activity, whereas TLR3- or TLR4-mediated death was dependent on TRIF and RIPK3. Unexpectedly, combined deletion of Atg16l1 and Zbp1 accelerated LPS-mediated necroptosis and sepsis in mice. Thus, ZBP1 drives necroptosis in the absence of the RIPK1-RHIM, but suppresses this process when multiple RHIM-domain containing proteins accumulate. These findings identify autophagy as a central regulator of innate inflammation governed by RHIM-domain proteins., Competing Interests: JL, HP, JH, TM, MR, MX, BM, Mv, KN, AM Affiliated with Genentech. No other competing interests to declare, (© 2019, Lim et al.)

Here, the actions of melittin, the active molecule of apitoxin or bee venom, were investigated on human red blood cells (RBCs) using quantitative phase imaging techniques. High-resolution real-time 3-D refractive index (RI) measurements and dynamic 2-D phase images of individual melittin-bound RBCs enabled in-depth examination of melittin-induced biophysical alterations of the cells. From the measurements, morphological, intracellular, and mechanical alterations of the RBCs were analyzed quantitatively. Furthermore, leakage of haemoglobin (Hb) inside the RBCs at high melittin concentration was also investigated.

In this paper, we present the optical characterisations of diabetic red blood cells (RBCs) in a non-invasive manner employing three-dimensional (3-D) quantitative phase imaging. By measuring 3-D refractive index tomograms and 2-D time-series phase images, the morphological (volume, surface area and sphericity), biochemical (haemoglobin concentration and content) and mechanical (membrane fluctuation) parameters were quantitatively retrieved at the individual cell level. With simultaneous measurements of individual cell properties, systematic correlative analyses on retrieved RBC parameters were also performed. Our measurements show there exist no statistically significant alterations in morphological and biochemical parameters of diabetic RBCs, compared to those of healthy (non-diabetic) RBCs. In contrast, membrane deformability of diabetic RBCs is significantly lower than that of healthy, non-diabetic RBCs. Interestingly, non-diabetic RBCs exhibit strong correlations between the elevated glycated haemoglobin in RBC cytoplasm and decreased cell deformability, whereas diabetic RBCs do not show correlations. Our observations strongly support the idea that slow and irreversible glycation of haemoglobin and membrane proteins of RBCs by hyperglycaemia significantly compromises RBC deformability in diabetic patients.

The characterization of white blood cells (WBCs) is crucial for blood analyses and disease diagnoses. However, current standard techniques rely on cell labeling, a process which imposes significant limitations. Here we present three-dimensional (3D) optical measurements and the label-free characterization of mouse WBCs using optical diffraction tomography. 3D refractive index (RI) tomograms of individual WBCs are constructed from multiple two-dimensional quantitative phase images of samples illuminated at various angles of incidence. Measurements of the 3D RI tomogram of WBCs enable the separation of heterogeneous populations of WBCs using quantitative morphological and biochemical information. Time-lapse tomographic measurements also provide the 3D trajectory of micrometer-sized beads ingested by WBCs. These results demonstrate that optical diffraction tomography can be a useful and versatile tool for the study of WBCs.

Rapid identification of bacterial species is crucial in medicine and food hygiene. In order to achieve rapid and label-free identification of bacterial species at the single bacterium level, we propose and experimentally demonstrate an optical method based on Fourier transform light scattering (FTLS) measurements and statistical classification. For individual rod-shaped bacteria belonging to four bacterial species (Listeria monocytogenes, Escherichia coli, Lactobacillus casei, and Bacillus subtilis), two-dimensional angle-resolved light scattering maps are precisely measured using FTLS technique. The scattering maps are then systematically analyzed, employing statistical classification in order to extract the unique fingerprint patterns for each species, so that a new unidentified bacterium can be identified by a single light scattering measurement. The single-bacterial and label-free nature of our method suggests wide applicability for rapid point-of-care bacterial diagnosis.

Red blood cells (RBCs) from the cord blood of newborn infants have distinctive functions in fetal and infant development. To systematically investigate the biophysical characteristics of individual cord RBCs in newborn infants, a comparative study was performed on RBCs from the cord blood of newborn infants and from adult mothers or nonpregnant women using optical holographic microtomography. Optical measurements of the distributions of the three-dimensional refractive indices and the dynamic membrane fluctuations of individual RBCs were used to investigate the morphological, biochemical, and mechanical properties of cord, maternal, and adult RBCs at the individual cell level. The volume and surface area of the cord RBCs were significantly larger than those of the RBCs from nonpregnant women, and the cord RBCs had more flattened shapes than that of the RBCs in adults. In addition, the hemoglobin (Hb) content in the cord RBCs from newborns was significantly higher. The Hb concentration in the cord RBCs was higher than that in the nonpregnant women or maternal RBCs, but they were within the physiological range of adults. Interestingly, the amplitudes of the dynamic membrane fluctuations in cord RBCs were comparable to those in nonpregnant women and maternal RBCs, suggesting that the deformability of cord RBCs is similar to that of healthy RBCs in adults.

We present optical measurements of morphology and refractive indexes (RIs) of human downy arm hairs using three-dimensional (3-D) quantitative phase imaging techniques. 3-D RI tomograms and high-resolution two-dimensional synthetic aperture images of individual downy arm hairs were measured using a Mach–Zehnder laser interferometric microscopy equipped with a two-axis galvanometer mirror. From the measured quantitative images, the RIs and morphological parameters of downy hairs were noninvasively quantified including the mean RI, volume, cylinder, and effective radius of individual hairs. In addition, the effects of hydrogen peroxide on individual downy hairs were investigated.

The identification and quantification of specific molecules are crucial for studying the pathophysiology of cells, tissues, and organs as well as diagnosis and treatment of diseases. Recent advances in holographic microspectroscopy, based on quantitative phase imaging or optical coherence tomography techniques, show promise for label-free noninvasive optical detection and quantification of specific molecules in living cells and tissues (e.g., hemoglobin protein). To provide important insight into the potential employment of holographic spectroscopy techniques in biological research and for related practical applications, we review the principles of holographic microspectroscopy techniques and highlight recent studies.

Two-dimensional angle-resolved light scattering maps of individual rod-shaped bacteria are measured at the single-cell level. Using quantitative phase imaging and Fourier transform light scattering techniques, the light scattering patterns of individual bacteria in four rod-shaped species (Bacillus subtilis, Lactobacillus casei, Synechococcus elongatus, and Escherichia coli) are measured with unprecedented sensitivity in a broad angular range from -70° to 70°. The measured light scattering patterns are analyzed along the two principal axes of rod-shaped bacteria in order to systematically investigate the species-specific characteristics of anisotropic light scattering. In addition, the cellular dry mass of individual bacteria is calculated and used to demonstrate that the cell-to-cell variations in light scattering within bacterial species is related to the cellular dry mass and growth.

We present an optical holographic micro-tomographic technique for imaging both the three-dimensional structures and dynamics of biological cells. Optical light field images of a sample, illuminated by a plane wave with various illumination angles, are measured in a common-path interferometry, and thus both the three-dimensional refractive index tomogram and two-dimensional dynamics of live biological cells are measured with extremely high sensitivity. The applicability of the technique is demonstrated through quantitative and measurements of morphological, chemical, and mechanical parameters at the individual cell level.

3-D refractive index (RI) distribution is an intrinsic bio-marker for the chemical and structural information about biological cells. Here we develop an optical diffraction tomography technique for the real-time reconstruction of 3-D RI distribution, employing sparse angle illumination and a graphic processing unit (GPU) implementation. The execution time for the tomographic reconstruction is 0.21 s for 96(3) voxels, which is 17 times faster than that of a conventional approach. We demonstrated the real-time visualization capability with imaging the dynamics of Brownian motion of an anisotropic colloidal dimer and the dynamic shape change in a red blood cell upon shear flow.