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The Research LINE-source (R-LINE) dispersion model for near-surface releases is a dispersion model developed to estimate the impacts of line sources, such as automobiles, on primary air pollutant levels. In a multiyear application in Atlanta, R-LINE simulations overestimated concentrations and spatial gradients compared to measurements. In this study we present a computationally efficient procedure for calculating annual average spatial fields and develop an approach for calibrating R-LINE concentrations with observational data. Simulated hourly concentrations of PM 2.5 , CO and NO x from mobile sources at 250 m resolution in the 20-county Atlanta area based on average diurnal emission profiles and meteorological categories were used to estimate annual averages. Compared to mobile source PM 2.5 impacts estimated by chemical mass balance with gas constraints (CMB-GC), a source apportionment model based on PM 2.5 speciation measurements, R-LINE estimates of traffic-generated PM 2.5 impacts were found to be higher by a factor of 1.8 on average across all sites. Compared to observations of daily 1 h maximum CO and NO x , R-LINE estimates were higher by factors of 1.3 and 4.2 on average, respectively. Annual averages estimated by R-LINE were calibrated by regression with observations from 2002 to 2011 at multiple sites for daily 1 h maximum CO and NO x and with measurement-based mobile source impacts estimated by CMB-GC for PM 2.5 . The calibration reduced normalized mean bias (NMB) from 29% to 0.3% for PM 2.5 , from 22% to −1% for CO, and from 303% to 49% for NO x . Cross-validation analysis (withholding sites one at a time) leads to NMB of 13%, 1%, and 69% for PM 2.5 , CO, and NO x , respectively. The observation-calibrated R-LINE annual average spatial fields were compared with pollutant fields from observation-blended, 12 km resolution Community Multi-scale Air Quality (CMAQ) model fields for CO and NO x , with Pearson correlation R 2 values of 0.55 for CO and 0.54 for NO x found. The calibrated fields of PM 2.5 were compared with 4 km resolution mobile source impact fields obtained from an indicator method using the observation-CMAQ fields, with an R 2 value of 0.53 found. The method developed provides high-resolution annual average spatial fields in a computationally efficient manner with low bias. The method is being applied in air quality planning efforts and the pollutant concentration fields are being used in long-term, fine spatial scale health studies. [ABSTRACT FROM AUTHOR]

A reliable database was established from the analysis of 60 royal jellies (RJs) produced by bee colonies selectively provided with artificial feed according to seasonal changes at an apiary in Gyeongsangnam-do, Korea. The moisture content of RJs ranged from 60.1 % to 67.1 % (average 65.2 %), and the trans -10-hydroxy‐2–decenoic acid (10-HDA) content ranged from 1.4% to 2.5% (average 1.9 %), indicating a wide range during the harvest period. The δ 13C values of the RJs varied from − 24.0‰ to − 17.2‰ (average −19.3‰). Sugar contents were 1.9–6.1 % for fructose, 2.8–5.5 % for glucose, and 0.7–7.7 % for sucrose. Pearson correlations were determined between harvest time and RJ components. The 10-HDA content showed a weak negative correlation with harvest time (p < 0.01). The δ 13C values and sucrose contents showed a weak positive correlation with harvest time when artificial feed was selectively supplied to bees according to seasonal changes (p < 0.01). This study highlights the characteristics and composition ranges of Korean RJ and compares the differences between the tested samples and RJ samples produced outside Korea. The results provide information necessary for determining the authenticity and quality grade of RJ by investigating the effect of bee colonies selectively provided with artificial feed according to seasonal changes on the compositional changes of RJ. • This study confirmed the compositional changes in RJ during the annual harvest. • Changes in the production method of royal jelly due to climate change. • Confirmation of correlation between harvest time and components of royal jelly. • The necessity of RJ grading based on carbon isotope ratio and sugars. [ABSTRACT FROM AUTHOR]

In the development of a mobile X-ray imaging apparatus, it is needed to pre-calculate the ambient leakage and stray radiation doses of the apparatus because the interest in exposure damage is increasing. This issue is strongly related to the additional radiation damage of the patients, caregivers, and radiologists around X-ray emission areas. Monte Carlo simulation with well-applied X-ray device's characteristics is a powerful method to estimate the leakage and stray radiation distribution. The first purpose of this study is to verify an MC simulation model with leakage radiation and stray radiation distribution for accurate scattered dose distribution. The second purpose is to optimize the lead shield part of the X-ray tube and predict various scattered dose distributions with the default and low-dose conditions in three clinical protocols (ChestAP, Abdomen Supine, and Pelvis AP). An X-ray mobile device was imported using a CAD import method for applying its complicated structures easily. X-ray photons were emitted on the anode with skipping the step of electrons hitting the anode for reducing the simulation time. We compared the air-kerma values between the experimental and simulation results under the leakage and stray radiation regulation. Then, we analyzed the dose distribution maps as a function of the size of the lead shield or the distance from the anode focal spot. The experimental and simulation results show similar leakage and stray radiation dose values as functions of the direction and the height, respectively. The analysis of the leakage and stray dose distribution maps shows that the maps strongly depend on the lead shield structures of the X-ray tube. Furthermore, all dose reduction rates of the three clinical protocols were over 40% and similar to the exposure dose reduction rates and remained constant as a function of the distance. This study demonstrates that our proposed simulation model can be used to develop other applications as well as a mobile X-ray imaging device and to protect against additional radiation damage with diverse clinical protocols. [ABSTRACT FROM AUTHOR]

Spondylocarpotarsal synostosis syndrome (SCTS) is a rare genetic disorder characterized by vertebral fusion, short stature, and skeletal anomalies. SCTS is primarily associated with mutations in filamin B. However, in this report, we present a unique case of SCTS in a 28-year-old male who complained of neck and shoulder pain persisting for 1 year. His clinical presentation included radioulnar synostosis, cervical spine anomalies (scoliosis and agenesis of the posterior arch of C1), and a history of polydactyly. Genetic analysis revealed mutations in GMNN and DLL1. To the best of our knowledge, this is the first report on the association of SCTS with these genes.

Self-organizing brain organoids provide a promising tool for studying human development and disease. Here we created human forebrain organoids with stable and homogeneous expression of channelrhodopsin-2 (ChR2) by generating AAVS1 safe harbor locus-targeted, ChR2 knocked-in human pluripotent stem cells (hPSCs), followed by the differentiation of these genetically engineered hPSCs into forebrain organoids. The resulting ChR2-expressing human forebrain organoids showed homogeneous cellular expression of ChR2 throughout entire regions without any structural and functional perturbations and displayed consistent and robust neural activation upon light stimulation, allowing for the non-virus mediated, spatiotemporal optogenetic control of neural activities. Furthermore, in the hybrid platform in which brain organoids are connected with spinal cord organoids and skeletal muscle spheroids, ChR2 knocked-in forebrain organoids induced strong and consistent muscle contraction upon brain-specific optogenetic stimulation. Our study thus provides a novel, non-virus mediated, preclinical human organoid system for light-inducible, consistent control of neural activities to study neural circuits and dynamics in normal and disease-specific human brains as well as neural connections between brain and other peripheral tissues., Competing Interests: The authors have no potential conflicts of interest to disclose., (© 2024 The Author(s). Bioengineering & Translational Medicine published by Wiley Periodicals LLC on behalf of American Institute of Chemical Engineers.)

Introduction: The study aimed to identify predictors associated with long-term tobacco cessation at 12-month follow-up among users of the National Smoking Cessation Services (NSCS) in Korea., Methods: To measure the long-term effect of NSCS delivery, the target sample size of 5167 adult smokers registered in the NSCS in 2018 was enrolled with proportional random sampling. A multiple logistic regression analysis (crude, adjusted) was performed to identify the changes in smoking status at the 12-month follow-up after the last NSCS enrollment and the potential factors associated with changes in smoking status., Results: The response rate to reach the number of subjects targeted was 22.4%. A total of 41.2% of the tobacco users enrolled had successfully quit at baseline, and the 7-day point prevalence of tobacco cessation at the follow-up at 12 months, via a telephone survey, was 34.4%. Factors positively associated with cessation at the 12-month follow-up were longer experience with tobacco abstinence and additional quitting attempts with or without NSCS enrollment, although every additional quit attempt with NSCS use had a better outcome. In addition, having a successful quit outcome with NSCS use at the baseline and having more satisfaction with the service of professional counseling or incentives than others provided by NSCS, increased cessation at follow-up after adjustment of other factors considered., Conclusions: In addition to multiple quitting attempts, longer experience with tobacco abstinence, and additional enrollment in NSCS, the service experience, and satisfaction with the content that NSCS offered, might improve the lasting success of abstinence. These results might be considered to improve the contents and protocols of the NSCS for better outcomes., Competing Interests: The authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. The authors declare that they have no competing interests, financial or otherwise, related to the current work. All the authors report that since the initial planning of the work their institutions received support from the Korean Ministry of Health and Welfare (11-1352000-002705-01)., (© 2024 Park J. et al.)

Background and Objectives: Patients recovering from mild coronavirus disease (COVID-19) reportedly have dysphagia or difficulty in swallowing. We compared the prevalence of dysphagia between patients diagnosed with mild COVID-19 and those diagnosed with aspiration pneumonia alone. Materials and Methods: A retrospective study was conducted from January 2020 to June 2023 in 160 patients referred for a videofluoroscopic swallowing study (VFSS) to assess for dysphagia. The cohort included 24 patients with mild COVID-19 and aspiration pneumonia, 30 with mild COVID-19 without aspiration pneumonia, and 106 with aspiration pneumonia alone. We reviewed the demographic data, comorbidities, and VFSS results using the penetration-aspiration scale (PAS) and functional dysphagia scale (FDS). Results: In a study comparing patients with mild COVID-19 (Group A) and those with aspiration pneumonia alone (Group B), no significant differences were observed in the baseline characteristics, including the prevalence of dysphagia-related comorbidities between the groups. Group A showed milder dysphagia, as evidenced by lower PAS and FDS scores, shorter oral and pharyngeal transit times ( p = 0.001 and p = 0.003, respectively), and fewer residues in the vallecula and pyriform sinuses ( p < 0.001 and p < 0.03, respectively). When Group A was subdivided into those with COVID-19 with (Group A1) and without aspiration pneumonia (Group A2), both subgroups outperformed Group B in terms of specific VFSS metrics, such as oral transit time ( p = 0.01), pharyngeal transit time ( p = 0.04 and p = 0.02, respectively), and residue in the vallecula ( p = 0.04 and p = 0.02, respectively). However, Group B showed improved triggering of the pharyngeal swallowing reflex compared with Group A2 ( p = 0.02). Conclusion: Mild COVID-19 patients showed less severe dysphagia than those with aspiration pneumonia alone. This finding was consistent across VFSS parameters, even when the COVID-19 group was subdivided based on the status of aspiration pneumonia.

Recent discoveries in stem cell and developmental biology have introduced a new era marked by the generation of in vitro models that recapitulate early mammalian development, providing unprecedented opportunities for extensive research in embryogenesis. Here, we present an overview of current techniques that model early mammalian embryogenesis, specifically noting models created from stem cells derived from two significant species: Homo sapiens, for its high relevance, and Mus musculus, a historically common and technically advanced model organism. We aim to provide a holistic understanding of these in vitro models by tracing the historical background of the progress made in stem cell biology and discussing the fundamental underlying principles. At each developmental stage, we present corresponding in vitro models that recapitulate the in vivo embryo and further discuss how these models may be used to model diseases. Through a discussion of these models as well as their potential applications and future challenges, we hope to demonstrate how these innovative advances in stem cell research may be further developed to actualize a model to be used in clinical practice., (© 2023. The Author(s).)

While recent research has shown that holographic displays can represent photorealistic 3D holograms in real time, the difficulty in acquiring high-quality real-world holograms has limited the realization of holographic streaming systems. Incoherent holographic cameras, which record holograms under daylight conditions, are suitable candidates for real-world acquisition, as they prevent the safety issues associated with the use of lasers; however, these cameras are hindered by severe noise due to the optical imperfections of such systems. In this work, we develop a deep learning-based incoherent holographic camera system that can deliver visually enhanced holograms in real time. A neural network filters the noise in the captured holograms, maintaining a complex-valued hologram format throughout the whole process. Enabled by the computational efficiency of the proposed filtering strategy, we demonstrate a holographic streaming system integrating a holographic camera and holographic display, with the aim of developing the ultimate holographic ecosystem of the future., (© 2023. The Author(s).)

Complex spatial light modulation, which can simultaneously control the amplitude and phase of light, is an essential optical technology for holographic display. We propose a twisted nematic liquid crystal (TNLC) mode with an in-cell type embedded geometric phase (GP) plate for full-color complex spatial light modulation. The proposed architecture provides an achromatic full-color complex light modulation capability in the far-field plane. The feasibility and working characteristics of the design are validated through numerical simulation.

Background/aim: Adenosine and 4 G-protein-associated membrane receptors (A 1 , A 2A , A 2B , and A 3 ) and their derivatives regulate the central nervous, cardiovascular, peripheral, and immune system. We developed a novel selective A 3 AR antagonist, HL3501, and examined its anti-fibrotic effects across various models., Materials and Methods: The anti-fibrotic activity of HL3501 was evaluated in three cell lines (HK2, LX2, and Primary hepatic stellate cell) and a methionine-choline-deficient (MCD) model including use of mouse pharmacokinetics (PK)., Results: HL3501 decreased alpha-smooth muscle actin (α-SMA) and collagen 1 in TGF-β1-induced pro-fibrotic activation in HK2 cells. HL3501 also inhibited TGF-β1-induced HSC activation, which resulted in reduction of α-SMA and fibronectin in LX2 and human primary HSCs. In the nonalcoholic fatty liver disease activity score (NAS) analysis, HL3501 showed improved anti-steatosis and anti-inflammatory activity. The mouse PK study revealed the oral bioavailability (%F) of HL3501 at 30 mg/kg and 60 mg/kg as 92.5 and 107.2%, respectively., Conclusion: HL3501 presents anti-fibrotic effects in in vitro and in vivo studies. We also demonstrated that HL3501 is orally available and has a good bioavailability (BA >90%) profile from in mouse PK. HL3501, therefore, has a therapeutic potential for various fibrotic diseases, including those of liver and kidney tissues., (Copyright © 2022, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Purpose: The A3 adenosine receptor (A3AR) is a known therapeutic target for glaucoma treatment. In this study, we developed HL3501 and examined its selectivity profile and in vitro and in vivo effects., Methods: For the rabbit model, intraocular pressure (IOP) was increased by laser photocoagulation of the trabecular meshwork (TM). The rabbits were then topically treated with HL3501, latanoprost, timolol, or vehicle for 3 weeks. For the mouse model, HL3501, latanoprost, or vehicle was administered following induced IOP elevation by dexamethasone (Dex). The IOP of all rabbits and mice was measured. Electroretinography was performed on both eyes of dark-adapted anesthetized mice on days 0 and 21. The mice's eyes were enucleated at the end of the treatment for immunofluorescence staining., Results: HL3501 was highly specific to the A3AR and inhibitory of A3AR function. In the rabbit glaucoma model, HL3501 and latanoprost significantly decreased the IOP. In the Dex-treated mouse model, HL3501 and latanoprost significantly decreased the IOP and increased the b-wave amplitude as compared with the vehicle treatment. HL3501 and latanoprost also inhibited fibronectin and α-smooth muscle actin expression induced by Dex treatment., Conclusions: HL3501 had effects similar to those of latanoprost in reducing ocular hypertension in animal models. HL3501 could be used as a novel approach to treat glaucoma., Translational Relevance: HL3501 is a novel preclinical compound targeting the A3 adenosine receptor, which may also be a new treatment option to fill the unmet needs of many glaucoma patients.

Objective: In South Korea, the placement of orphans in institutions is still common, despite evidence of its adverse influence on children's psychological, emotional, physical, and cognitive development. In this preliminary study, we evaluate whether system-wide positive behavior support (SWPBS) is effective for decreasing externalizing problems in institutionalized children., Methods: SWPBS was provided for one month to 36 school-aged boys who had lived in an orphanage for an average of 8.72 years (SD=2.52), along with their 10 caregivers. Direct observation of the frequency of target behaviors in the participating children, caregivers' ratings of the severity of children's problematic behaviors, self-reported caregiving stress (i.e., Parenting Stress Scale), and intervention fidelity were dependent variables., Results: After receiving SWPBS, the frequency of problematic behaviors in the participating children showed a mean decrease of 73.6%. The caregivers also reported seeing a decrease in the severity of their children's problematic behaviors after SWPBS compared to before., Conclusion: SWPBS may be a promising intervention to decrease externalizing behaviors in school-aged children who have been living in institutions for a long time and have shown mental health issues.

A slim beam deflector that satisfies both a large steering angle and a large area can be very useful in various applications. However, a smaller electrode pitch for a large steering angle and enlargement of its area are trade-off relations due to the limited number of control channels in an electrically tunable beam deflector system. For a large steering angle in the active area where actual diffraction occurs, an indium tin oxide electrode of 2 µm pitch was implemented through a stepper lithography. The via-hole process was developed to expand the reduced active area due to the small electrode pitch. We developed a beam deflector with 7200 controllable channels in an active area of 14.4 m m ×14.4 m m . The maximum steering angle is 7.643° at a wavelength of 532 nm.

Highly efficient transmission-type beam deflectors that have high angular resolution have been widely used for various applications. Continuously tunable beam deflectors have also been needed for many purposes. An indium-tin-oxide (ITO), widely used for transparent electrodes, was placed on the upper and lower glass substrate. The ITO layer on the lower substrate was patterned by the contact mask aligner for relatively wide input and output pad compared to main grating ITO patterns in the active area. These input and output pads on the lower substrate are connected to each driving integrated circuit (IC), which has 360 channels for continuous control. A small pixel pitch of grating patterns of 6 μm (the electrode width is 3 μm with a 3 μm spacing) was developed, and the maximum diffraction angle is calculated and measured at 2.541° with a wavelength of 532 nm. A minimal cell gap of 2.5 μm was applied for the full 2 π phase modulation by using a high-birefringence liquid crystal. A driving module for continuous beam steering is also developed and applied to the beam deflector system. A diffraction efficiency of about 50.9% is observed at an angle of diffraction about 2.541°.

Purpose: Maintenance of a remifentanil infusion during anesthetic emergence has been reported to decrease the incidence of coughing and thereby help to ensure a smooth emergence. It may, however, cause respiratory depression and possibly delay emergence. The purpose of this study was to investigate the effect of a single dose of dexmedetomidine combined with a low-dose remifentanil infusion on cough suppression during emergence from general anesthesia., Methods: American Society of Anesthesiologists physical status I-II adults undergoing elective thyroidectomy under sevoflurane anesthesia were recruited and randomly allocated to receive either dexmedetomidine 0.5 μg·kg(-1) iv (Group D, n = 70) or saline (Group S, n = 71), each combined with a low-dose remifentanil infusion ten minutes before the end of surgery. Coughing was assessed using a four-point scale. The respiratory rate (RR), heart rate (HR), and mean arterial pressure were also recorded., Results: The incidence of coughing was lower in Group D than in Group S (64% vs 91%, respectively; mean difference 27%; 95% confidence interval [CI] 13 to 41; P < 0.001). The median cough grade at extubation was also lower in Group D. Mean arterial pressure and HR were elevated in Group S during tracheal extubation but were similar to baseline values in Group D. There was no difference in RR between the two groups throughout the study. A small delay in extubation was observed in Group D (3 minutes longer than Group S; 95% CI 2 to 4; P < 0.001)., Conclusion: Compared with an infusion of low-dose remifentanil alone, the addition of a single dose (0.5 μg·kg(-1)) of dexmedetomidine during emergence from sevoflurane-remifentanil anesthesia was effective in attenuating coughing and hemodynamic changes and did not exacerbate respiratory depression after thyroid surgery. This trial was registered at Clinicaltrial.gov, identifier: NCT01774305.

Background: We estimated the nationwide burden of nosocomial S. aureus bloodstream infection (SA-BSI), a major cause of nosocomial infection, in South Korea., Methods: To evaluate the nationwide incidence of nosocomial SA-BSI, cases of SA-BSI were prospectively collected from 22 hospitals with over 500 beds over 4?months. Data on patient-days were obtained from a national health insurance database containing the claims data for all healthcare facilities in South Korea. The additional cost of SA-BSI was estimated through a matched case?control study. The economic burden was calculated from the sum of the medical costs, the costs of caregiving and loss of productivity., Results: Three hundred and thirty nine cases of nosocomial SA-BSI were included in the study: 254 cases of methicillin-resistant SA-BSI (MRSA-BSI) and 85 cases of methicillin-susceptible SA-BSI (MSSA-BSI). Death related to BSI occurred in 81 cases (31.9%) of MRSA-BSI and 12 cases (14.1%) of MSSA-BSI. The estimated incidence of nosocomial MRSA-BSI was 0.12/1,000 patient-days and that of nosocomial MSSA-BSI, 0.04/1,000 patient-days. The estimated annual cases of nosocomial BSI were 2,946 for MRSA and 986 for MSSA in South Korea. The additional economic burden per case of nosocomial SA-BSI was US $20,494 for MRSA-BSI and $6,914 for MSSA-BSI. Total additional annual cost of nosocomial SA-BSI was $67,192,559., Conclusion: In view of the burden of nosocomial SA-BSI, a national strategy for reducing nosocomial SA-BSI is urgently needed in South Korea.

Although the two ciliopathies Bardet-Biedl syndrome and nephronophthisis share multiple clinical manifestations, the molecular basis for this overlap remains largely unknown. Both BBS11 and NPHP7 are unusual members of their respective gene families. Although BBS11/TRIM32 represents a RING finger E3 ubiquitin ligase also involved in hereditary forms of muscular dystrophy, NPHP7/Glis2 is a Gli-like transcriptional repressor that localizes to the nucleus, deviating from the ciliary localization of most other ciliopathy-associated gene products. We found that BBS11/TRIM32 and NPHP7/Glis2 can physically interact with each other, suggesting that both proteins form a functionally relevant protein complex in vivo. This hypothesis was further supported by the genetic interaction and synergist cyst formation in the zebrafish pronephros model. However, contrary to our expectation, the E3 ubiquitin ligase BBS11/TRIM32 was not responsible for the short half-life of NPHP7/Glis2 but instead promoted the accumulation of mixed Lys(48)/Lys(63)-polyubiquitylated NPHP7/Glis2 species. This modification not only prolonged the half-life of NPHP7/Glis2, but also altered the subnuclear localization and the transcriptional activity of NPHP7/Glis2. Thus, physical and functional interactions between NPHP and Bardet-Biedl syndrome gene products, demonstrated for Glis2 and TRIM32, may help to explain the phenotypic similarities between these two syndromes.

We propose a color moiré pattern simulation and analysis method in integral imaging for finding the moiré-reducing tilted angle of a lens array. According to the tilted angle, the color moiré patterns are simulated on the assumption of ray optics. The spatial frequencies of the color moiré patterns are numerically analyzed using a spatial Fourier transform for finding the optimal angle where the moiré is reduced. With the proposed technique the visualization of the color moiré pattern and its analysis are enabled. The moiré-reduced three-dimensional images can be displayed. The principle of the proposed method, simulation results, and their analysis are provided. Experimental results verify the validity of the proposed method.

We propose a thin and compact integral imaging system using electroluminescent (EL) films as backlight. EL film has the advantage that it can operate continuously even when it is cut or punctured. Using this characteristic, we generate an array of pinholes on EL film to form a point light-source array for reconstructing three-dimensional (3D) images based on integral imaging. The EL pinhole film is attached on another EL film and they are electrically controlled to generate a point light-source array or a surface light source; hence, the system converts between 3D and two-dimensional (2D) modes. Taking advantage of the flexibility of EL films, we also propose a flexible 3D/2D convertible integral imaging system with a wide viewing angle using a curved EL film. We explain the principle of the proposed methods and present experimental results.

A thin and lensless two-dimensional (2D) to three-dimensional (3D) convertible display based on integral imaging using an organic light emitting diode (OLED) panel as a direct emissive light source is proposed with improved optical efficiency. A point light source array for 2D-3D convertible display is formed on the surface light source, i.e., the OLED panel. However, a blurring effect and color separation result from the finite (nonzero) size of point light sources since each point light source is generated by a pixel of the OLED panel. Simulation results for a blurring effect and color separation in terms of rays from a light source with finite size is presented. The proposed system has a thin structure and simple convertibility because it does not need any additional optical element to provide 2D-3D convertibility.

A display system that simultaneously displays two-dimensional (2D) and three-dimensional (3D) images using a pinhole array on a liquid crystal (LC) panel is proposed. Using the transparent structure of the LC panel, the system can generate or eliminate pinholes electrically and can display a 3D image in a selectable specific area of the display panel, while 2D images are displayed on the rest of the screen. An analysis showing the advantages and limitations of the proposed system is provided. Finally, the proposed principle is proven by experimental results.

A novel approach to an integral imaging system using a pliable plastic optical fiber array is proposed. The proposed system has the advantage that it can utilize a light source for three-dimensional (3D) images at an arbitrary location because the point light sources are formed by the plastic fiber array with flexible optical paths. Two-dimensional images can also be expressed in the proposed system. The light efficiency of this system is high compared with previous point light source array integral imaging systems. The feasibility of the proposed method is explained and demonstrated with experiments.

A depth-enhanced three-dimensional integral imaging system with electrically variable image planes is proposed. For implementing the variable image planes, polymer-dispersed liquid-crystal (PDLC) films and a projector are adopted as a new display system in the integral imaging. Since the transparencies of PDLC films are electrically controllable, we can make each film diffuse the projected light successively with a different depth from the lens array. As a result, the proposed method enables control of the location of image planes electrically and enhances the depth. The principle of the proposed method is described, and experimental results are also presented.

Background: Cystatin C (cysC) is said to be an ideal marker for glomerular filtration rate (GFR), independent of external factors such as age, nutrition and inflammation. The authors compared the accuracy and precision of cysC-based and creatinine (Cr)-based GFR estimates using Cr51-EDTA GFR method as a reference., Methods: Serum concentrations of cysC and Cr were measured in adults over 17 yr (n=170) and children below 17 yr (n=79) who had had GFR estimated by Cr51-EDTA method. CysC-based GFR was estimated by the formula of Thierry [CysC-based GFR estimates (mL/min/1.73 m2)=78 x (1/cysC, in mg/L)+4] and Cr-based GFR by the formula of modified Modification of Diet in Renal Disease [MDRD II, Cr-based GFR estimates (mL/min/1.73 m2)=186 x (Scr)(-1.154) x (Age)(-0.203) x 0.742 (for a female patient) x 1.212 (for a black patient)., Results: In comparison with Cr51-EDTA GFR, in children below 17 yr, the bias +/- standard deviation (SD) of cysC-based and Cr-based GFR estimates were 7.5 +/- 6.1 and 106.5 +/- 98.2, respectively, in the range of below 90 of Cr51-EDTA GFR (mL/min/1.73 m2), and 33.7 +/- 33.0 and 174.4 +/- 18.8 in the range of over 90. In adults over 17 yr, the respective figures were 13.1 +/- 11.0 and 17.4 +/- 29.8 in below 90, and 21.2 +/- 20.1 and 83.6 +/- 108.8 in over 90 of Cr51-EDTA GFR., Conclusions: CysC-based GFR estimates show acceptable ranges of biases over the whole age and GFR ranges. CysC-based GFR estimates is considered to be the marker for GFR, which could be used without limitation of age and GFR ranges.

Background: Bayer Rapidpoint 400 analyzer for point of care testing (POCT) uses fixed quality control (QC) range even when the lot number of a cartridge for quality control changes. To evaluate the fixed QC range recommended by the manufacturer, we analyzed internal QC data of 9 analyzers with Six Sigma metrics., Materials and Methods: We investigated QC data of 9 analyzers over 5 months from May to September, 2004 for 8 parameters (pH, pCO(2), pO(2), Na(+), K(+), iCa(++), Cl(-), and glucose). One hundred eighty six groups of QC data were analyzed with capability index (C(p)=total allowable error (TEa)/3 standard deviation (SD)) and capability index considering bias (C(pk),=(TEa-bias)/3 SD). Acceptability was evaluated with criteria of 1.33 C(pk), 4 sigma level or quality criteria of the Clinical Laboratory Improvement Amendments of 1988 (CLIA'88)., Results: In 80.7% (150 of 186 groups), both C(p) and C(pk) were at or above 1.33, which indicated that the use of fixed QC range was adequate. In 19.3% (36 of 186 groups), C(pk) was below 1.33, which indicated the inadequacy of fixed QC range. Among them 14.5% (27 of 186 groups) showed C(p) below 1.33, indicating that the errors had a random factor and 4.8% (9 of 186 groups) had C(p) at or above 1.33, indicating that the errors had a systematic factor., Conclusions: The quality criteria mandated by CLIA '88 was satisfied in about 80% of study groups using fixed QC ranges, but in about 20%, more strict instrument maintenance and specimen handling by operators, and quality improvement of QC materials by manufacturer was required.

Background: Cost containment through continuous quality improvement of medical service is required in an age of a keen competition of the medical market. Laboratory managers should examine the matters on make-or-buy decision periodically. On this occasion, a break-even point analysis can be useful as an analyzing tool. In this study, cost accounting and break-even point (BEP) analysis were performed in case that the immunoassay items showing a recent increase in order volume were to be in-house made., Methods: Fixed and variable costs were calculated in case that alpha fetoprotein (AFP), carcinoembryonic antigen (CEA), prostate-specific antigen (PSA), ferritin, free thyroxine (fT4), triiodothyronine (T3), thyroid-stimulating hormone (TSH), CA 125, CA 19-9, and hepatitis B envelope antibody (HBeAb) were to be tested with Abbott AxSYM instrument. Break-even volume was calculated as fixed cost per year divided by purchasing cost per test minus variable cost per test and BEP ratio as total purchasing costs at break-even volume divided by total purchasing costs at actual annual volume., Results: The average fixed cost per year of AFP, CEA, PSA, ferritin, fT4, T3, TSH, CA 125, CA 19-9, and HBeAb was 8,279,187 won and average variable cost per test, 3,786 won. Average break-even volume was 1,599 and average BEP ratio was 852%. Average BEP ratio without including quality costs such as calibration and quality control was 74%., Conclusions: Because the quality assurance of clinical tests cannot be waived, outsourcing all of 10 items was more adequate than in-house make at the present volume in financial aspect. BEP analysis was useful as a financial tool for make-or-buy decision, the common matter which laboratory managers meet with.

Integral imaging is one of the promising three-dimensional display techniques and has many advantages. However, one disadvantage of integral imaging is the limited image depth. The image can be displayed only around the central depth plane. We propose a depth-enhanced integral imaging using multilayered display devices. We locate transparent display devices that use liquid crystal in parallel to each other and incorporate them into an integral imaging system. As a result, the proposed method has multiple central depth planes and permits the limitation of expressible depth to be overcome. The principle of the proposed method is explained, and some experimental results are presented.

There have already been several analyses about the viewing angle of integral imaging (InIm). However, they can be applied only under the assumption that the original image is merely a single point source and are not suitable for application to an actual condition. We propose an improved analysis based on the actual InIm image, not on a single point source. It is possible to analyze and predict the viewing angle of an InIm system with good accuracy with the new analytic method because almost all the parameters of the InIm system such as the size and focal length of the lens array, image distance, the size and resolution of the image, and the location of the observers are included in this analysis.

A wide-viewing-angle integral three-dimensional imaging system made by curving a screen and a lens array is described. A flexible screen and a curved lens array are incorporated into an integral imaging system in place of a conventional flat display panel and a flat lens array. One can effectively eliminate flipped images by adopting barriers. As a result, the implemented system permits the limitation of viewing angle to be overcome and the viewing angle to be expanded remarkably. Using the proposed method, we were able to achieve a viewing angle of 33 degrees (one side) for real integral imaging and 40 degrees (one side) for virtual integral imaging, which is four times wider than that of the currently used conventional techniques. The principle of the implemented system is explained, and some experimental results are presented.

Cultured plant cells are a good system for the study of antioxidant mechanisms and for the mass production of antioxidants, because they can be grown under conditions of high oxidative stress. Alterations in the intracellular and extracellular activities of three antioxidant enzymes, superoxide dismutase (SOD), guaiacol-type peroxidase (POD), and glutathione peroxidase (GPX), were investigated in suspension cultures of sweetpotato (Ipomoea batatas) during cell growth. Intracellular SOD activities (units/mg protein) at 15 days after subculture (DAS) and 30 DAS were 10 and 20 times higher, respectively, compared with the SOD activity at 1 DAS, whereas intracellular specific POD and GPX activities did not significantly increase until after 15 DAS, when they rapidly increased. The extracellular activities of the three enzymes in culture medium were much higher than were the intracellular activities. The change in extracellular SOD activity was similar to that of extracellular GPX during cell growth. Those activities showed high levels until 5 DAS and then significantly decreased. Extracellular POD activity had an almost constant level regardless of the cell growth stage. In addition, intracellular SOD and POD isozymes were quite different from those isozymes in the culture medium. The changes in SOD and POD isozymes observed here suggest that different isozymes might modulate the levels of reactive oxygen intermediates during cell growth. Characterization of extracellular antioxidant enzymes discovered here would provide a new understanding for defense mechanism in plants., (Copyright 2004 Elsevier Ltd.)