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In this paper, RF transceiver for wireless backhaul system was designed and implemented. The requirement of RF transceiver was extracted with system link budget. And, the IF/RF modules composing the transceiver were also designed and fabricated. The implemented RF transceiver was verified with system loop-back test.

In this paper, we present an information registration method for an Augmented Reality Head-Up Display (AR-HUD) system. The AR-HUD system superimposes driving assistance warnings and instructions that correctly match the real world according to the driver's view. AR information registration is a necessary procedure prior to the presentation of these warnings and instructions. This need is important in the field of safe driving, where the driver should keep his attention to specific situations and decide the upcoming maneuvers. This paper presents an automated AR information registration method that can establish correspondences between cameras and HUD on the assumption that the view of the driver are fixed toward the front. We also verify some of the use cases in the implemented AR-HUD system based on a test-bed vehicle.

In this paper firstly current state and progress of LTE-based public safety network construction project is described, secondly emerging issues with designing LTE high-speed railway network are discussed, and finally a conclusion and future works are addressed. Two LTE networks are several similar features of LTE for public safety based radio access technology, 700 MHz frequency band, 10 MHz bandwidth, and nationwide deployment. Since the inter-network interference can cause the call disconnection with wireless train control which results in a fatal train accident, it is the most important thing at present for designing and planning LTE railway network to eliminate—not to mitigate or reduce—the radio interference, and therefore in our view it urgently needs to secure the reliability and survivability of the wireless train control system when we design and deploy both LTE networks together.

A driver should always pay attention to various situations which he faces inside and outside the car while driving and always keep eyes forward for safe driving. A vehicle augmented reality system provides the driver with safe and convenience information which matched with the real world through HUD. It makes the driver keep eyes forward road and other cars. We have developed the vehicle augmented reality system and various services and tested them on an indoor testbed This system provides driver with the forward situation awareness service, the lane change service, the lane departure service and so on displayed as the vehicle augmented reality. We describe the development contents and results of the developed vehicle augmented reality system focused on the lane-level guidance technology which determines the lane change or the lane departure using route information, road properties, the driving lane information, position, and so on.

As the speed of train trialled by the French National Rail Corporation has reached more than 500 km/h, the secure and continuous connection to the train control system has only grown more important. In this paper, current status and progress of national disaster safety network project and LTE-based integrated wireless network for railway in Korea, firstly, and the major challenges of LTE-R network to coexist with LTE public safety network are addressed in the aspect of the air interface requirements for the essential railway services. In our view, it is the most important thing at present for designing and planning LTE railway network to eliminate — not to mitigate or reduce — the radio interference, especially from the adjacent LTE public safety network to LTE-based wireless train control because they use the same frequency band.

In this paper, we introduce a vehicle augmented reality (AR) system to present information of driving situation awareness in a vehicle. Today, manufacturers related with vehicles have been pointing to AR as a next-generation visualization technology for in-car driving displays. Such in-vehicle AR-based display systems are helpful in reducing driver distractions, thereby increasing driver safety, and provide intelligent interactions for enhancing driver convenience. The proposed system offers information of driving situation and warning to a driver through the augmented reality using head-up display. The system consists of several sub-modules such as sensor, vehicle/pedestrian recognition, vehicle state information, driving information, time to collision (TTC), threat assessment, warning strategy, and display modules. We have defined the threat level and the presentation of AR information based on TTC values and driver's preference throughout experiments. The proposed system have been installed to a test vehicle with a vehicle AR information system prototype and carried out in the real road environments. The proposed system demonstrates to offer intuitively danger information according to the presentation rules to a driver on real road.

It develops in the development efforts about the terminal software platform while the telematics service is activated. Domestically, a standard is developed around the Korea Telematics Standardization Forum. And it is taken in reviews for the WIPI which is supporting the telematics. Internationally, it develops standards for the vehicle based platform in the standardization organizations like OSGi and GST. Under this background, this paper tries to propose the terminal software platform standard in which the vehicle information based telematics service can be taken. For this, firstly domestic and international telematics standard conditions are looked into around the terminal software platform. The terminal software platform standard proposed in this paper is illustrated in the architecture, the required function and the interface side.

Suspension cells of kidney bean were grown for 42 d in MS medium supplemented with growth regulators (2.0 mgL-1 2,4-D and 0.5 mgL-1 kinetin) or without At the stationary growth phase (42 d), the sugars were fractionated into the symplastic (ethanol and starch) and apoplastic [low-molecular pectin (lm-pectin), high-molecular pectin (hm-pectin), hemicellulose, and cellulose] sugars. The neutral sugars (NS) of hm-pectin and hemicellulose fractions were analyzed by GLC. The growth of the suspension cells in the liquid MS media, in terms of settled cell volume (SCV), remained similar, to the end of the experiment, irrespective of the presence or absence of growth regulators, indicating the nonnecessity of the exogenous growth regulators for the subculture. Total sugar (TS) of the ethanol fraction and NS of the Im-pectin of the suspension cells grown in the medium with growth regulators were higher than in the medium without growth regulators. However, starch content in the starch fraction and uronic acid (UA) content of the Im-pectin fraction did not exhibit any differences. From these results, it was suggested that the growth regulators modulated the structure of the cell wall polysaccharide. Analysis of the NS composition of the hm-pectin fractions revealed that the Rha, Arb, and Gal contents in the presence of growth regulators were higher than in the absence, while the Xyl, Man, and Glc contents in the presence of growth regulators were higher than in the absence, indicating the turnovers of rhamnogalacturonan and/or arabinogalactan. On the other hand, analysis of NS composition of hemicellulose fractions revealed that the Ara and Glc contents in the presence of growth regulators was higher than in the absence, whereas Xyl and Glc contents were nearly consistent, indicating the turnovers of arabinaogalactan I or II. The cellulose contents remained similar, irrespective of the presence (19.1%) or absence (18.7%) of growth regulators.

This paper is to provide the basic way of a acoustical evaluation and efficient control noise by investigating the limits of perceptual loudness of living environment and by finding out any correlation between Physical characteristics of noise and psychoacoustic parameters. The limits of perceptual loudness were selected by the subjects in a chamber for residential and working environment. And the noise sources were analyzed to find out whether there is any correlation with Zwicker parameters and ACF factors. In this study especially, to set up the domestic evaluation grade about floor impact noise. we`d like to suggest the loudness Perception research result as fundamental resource for setting up the evaluation grade through the result that is based on annoyance. In the result of this research, upper limit of heavy-weight impact noise was L-60, and lower limit of it was L-50. On the other hand, upper limit of light-weight impact noise was L-70, and lower limit of it was L-55. It seemed that the loudness of noise from vacuum cleaner noise does not affect its perceived noisiness. Noises implicated In human such as floor walking noise and talking sound, are the most irritating noise in office environment.

We cultured the suspension cells of kidney bean in MS media supplemented with one of five concentrations of CaCI2 [0,22,44 (control), 88, or 176 mg/L], and harvested them at the logistic (15 d) and early-stationary (30 d) phases. Cells grown at concentrations higher than 22 mg/L showed better proliferation than those at 0 mg/L The rate of proliferation also increased with higher concentrations. We fractionated the individual sugars into symplastic (EtOH and starch) and apoplastic (low-molecular pectin, high-molecular pectin, hemicellulose, and cellulose) components. Cells treated at the highest concentration (176 mg/L) exhibited the greatest amount of sugar in the EtOH and starch fraction during the logistic phase. In contrast, cells in the early stationary phase had the highest level of sugar at treatment concentrations of less than 22 mg/L. For treatment concentrations higher than 22 mg/L on Day 15, more pectin and hemicellulose was detected at greater amounts compared with those cells treated with 0 mg/L. However, at Day 30, concentrations higher than 44 mg/L induced greater amounts of pectin and hemicellulose than from the other concentrations. Cellulose was more abundant with the 0 mg/L treatment, and contents ranged from 17.4 to 25.5% in the primary cell walls over all treatment concentrations. These results indicate that CaCI2 modulates both symplastic and apoplastic sugar metabolism. Therefore, we suggest that the cell-wall structure may define the mode of polysaccharide biosynthesis during cell growth.

In this paper, the authors present an augmented forward collision warning system for Head-Up Display (HUD). The convergence of HUD and Augmented Reality (AR) needs challenge and make innovative application in the automobile industry. The authors focus on an advance of Forward Collision Warning System (FCWS) by the fusion of HUD and AR. The proposed system detects the frontal vehicles and pedestrians, assesses the imminent danger caused by the detected results, and alerts the augmented warnings to support safe driving practices.

The biochemistry and microbial ecology of 2 similar types of watery (mul) kimchi, containing sliced and unsliced radish and vegetables (nabak and dongchimi, respectively), were investigated. Samples from kimchi were fermented at 4, 10, and 20 °C were analyzed by plating on differential and selective media, high-performance liquid chromatography, and high-throughput DNA sequencing of 16S rDNA. Nabak kimchi showed similar trends as dongchimi, with increasing lactic and acetic acids and decreasing pH for each temperature, but differences in microbiota were apparent. Interestingly, bacteria from the Proteobacterium phylum, including Enterobacteriaceae, decreased more rapidly during fermentation at 4 °C in nabak cabbage fermentations compared with dongchimi. Although changes for Proteobacterium and Enterobacteriaceae populations were similar during fermentation at 10 and 20 °C, the homolactic stage of fermentation did not develop for the 4 and 10 °C samples of both nabak and dongchimi during the experiment. These data show the differences in biochemistry and microbial ecology that can result from preparation method and fermentation conditions of the kimchi, which may impact safety (Enterobacteriaceae populations may include pathogenic bacteria) and quality (homolactic fermentation can be undesirable, if too much acid is produced) of the product. In addition, the data also illustrate the need for improved methods for identifying and differentiating closely related lactic acid bacteria species using high-throughput sequencing methods.

This paper proposes an AR augmented reality based vehicular safety information system that provides warning information allowing drivers to easily avoid obstacles without being visually distracted. The proposed system consists of four stages: fusion data based object tracking, collision threat assessment, AR-registration, and a warning display strategy. It is shown experimentally that the proposed system can predict the threat of a collision from a tracked forward obstacle even during the nighttime and under bad weather conditions. The system can provide safety information for avoiding collisions by projecting information directly into the driver's field of view. The proposed system is expected to help drivers by conveniently providing safety information and allowing them to safely avoid forward obstacles.

Providing a suitable and efficient representation of a driver’s perspective is a way to reduce traffic accidents. In this paper, we first introduce a driver-centered AR (augmented-reality) HUD (head-up-display) system that superimposes augmented virtual objects onto a real scene under all types of driving situations including unfavorable weather (such as rainy, foggy, overcast, and snowy) conditions. We next explain the scenario and method used in our comparative experiments on a method for improving both the cognitive usability and visibility of drivers. For this, we comparatively analyzed not only information display locations but also information representation for six information types using a driving simulator with thirty subjects. For the effects on safety, the situational driver awareness of safety-related road events was measured. To determine the differences in the visual cognitive workload placed upon drivers, we tracked their eye movements. The subjective workload of the participants was assessed using the RSME (Rating Scale Mental Effort).

We introduce driver-oriented intelligent HVI (Human-Vehicle Interaction) system, which is designed to integrate the interfaces in the vehicle. The proposed HVI system monitors the vehicle, the cell phone, the car navigation system to recognize the driver's primary tasks and secondary tasks. It is estimated the driving workload from the status information, the output information is controlled based on the driving workload. We implemented the proposed HVI system with the vehicle information collector, the HVI cell phone and the HVI car navigation system. In this paper, the structure of the proposed HVI system is described and the implemented system deployment is represented. The proposed HVI system will be extended to be connected other IT devices in the vehicle environment and to estimate the driving workload more exactly.

Today, driving convenience has increased greatly owing to the availability of various telematics devices developed recently. However, this convenience often comes at the cost of driving safety. With the aim of achieving a balance between them, we propose a multi-modal interface for optimizing driving workload and describe an efficient design for the interface. To demonstrate the effectiveness of the interface, we use it in a simulator environment resembling real driving situations, designed to allow the interface to detect and analyze states of both the driver and the vehicle in real time. The proposed interface transfers information by optimizing the driving workload such that it within a range appropriate in view of driver safety. In the future, we intend to demonstrate the feasibility of the proposed interface through multiple experiments.

Purpose The purpose of this study was to investigate the pharmacokinetics and safety of intravitreal povidone-iodine (PVI) and its efficacy against experimental Staphylococcus epidermidis endophthalmitis. Methods In phase I, forty New Zealand white rabbits were divided into groups I and II and received intravitreal 0.1% and 0.3% PVI, respectively. Electroretinography (ERG) and histologic examinations were conducted at baseline, 6, and 12 hours. Half-life was determined using high-performance liquid chromatography. In phase II, after the induction of S. epidermidis endophthalmitis, 0.1% and 0.3% PVI were injected intravitreally once in groups A and B and three times every second day in groups C and D (n = 10 in each group). Electroretinographs, histologic examinations, and vitreous cultures were conducted on day 14. Results Electroretinography and histologic examinations did not reveal any notable retinal damage in phase I in either group. Half-lives were 3.27 and 3.58 hours in groups I and II, respectively. In phase II, all groups demonstrated marked improvement, compared to controls. Bacterial growth was found in four eyes in group A (20, 60, 60, and 70 colony forming units [CFU]) and in three eyes in group B (20, 40, and 60 CFU) but not in those belonging to groups C and D at day 14. Retinal damage with lymphocyte infiltration in the inner retinal layers was more common in groups A and B than in groups C and D. Conclusions Half-life of PVI was approximately 3 hours in the vitreous. Repeated injection of intraocular PVI, even at low concentrations, is most likely to be effective for the treatment of bacterial endophthalmitis.

Vitrectomy with Perfluorocarbon Liquid versus Combined Encircling for Retinal Detachment with Giant Retinal Tear 이동현1⋅김경호1,2⋅박성후3⋅변익수1,2,4⋅이지은3,4 Dong Hyun Lee, MD, Kyong Ho Kim, MD, Sung Who Park, MD, Ik Soo Byon, MD, Ji Eun Lee, MD, PhD 양산부산대학교병원 안과학교실, 양산부산대학교병원 의생명융합연구소, 부산대학교병원 안과학교실, 부산대학교 의학전문대학원 안과학교실 Department of Ophthalmology, Pusan National University Yangsan Hospital, Yangsan, Korea Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Korea Department of Ophthalmology, Pusan National University Hospital , Busan, Korea Department of Ophthalmology, Pusan National University School of Medicine, Busan, Korea

양산부산대학교병원 안과학교실, 양산부산대학교병원 의생명융합연구소, 부산대학교병원 안과학교실, 부산대학교 의학전문대학원 안과학교실 Department of Ophthalmology, Pusan National University Yangsan Hospital, Yangsan, Korea Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital , Yangsan, Korea Department of Ophthalmology, Pusan National University Hospital , Busan, Korea Department of Ophthalmology, Pusan National University School of Medicine, Yangsan, Korea

During the last decade, spatio-temporal database have become increasingly important in many application areas such as GIS, engineering information systems, CAD/CAM, remote sensing and environmental modeling. An important research issue in the field of GIS is the spatio-temporal analysis of huge geographical features with time such as buildings, roads, and so on. We propose a unified visualization framework for spatial and temporal analysis in 4D GIS. We also introduce a novel interoperable geographical data service concept; so-called, Virtual World Mapping (VWM) that can map 3D graphic world with real-world video. Our proposed method can easily retrieve geographical information in various views such as 2D, 3D views and videos. Our proposed system architecture also has an advantage that can provide video geographical information service without any processing such as frame segment trees construction and image segmentation.

MediaGIS is a concept of tightly integrated multimedia with spatial information. VideoGIS is an example of MediaGIS focused on the integration and interaction of video and spatial information. Our suggested GeoVideo, a new concept of interactive geographic video has its key feature in interactiveness. In GeoVideo, the geographic tasks such as browsing, searching, querying, and spatial analysis can be performed based on video itself. GeoVideo can have the meaning of paradigm shift from artificial, static, abstracted, and graphical paradigm to natural, dynamic, real, and image-based paradigm. We discuss about the integration of video and geography and also suggest the GeoVideo system design. Studies on the systematic architecture utilizing the video stream and MPEG must follow with the inter-disciplinary studies especially on the computer vision and virtual reality.

Urban facility management is one of the applications to which the virtual GIS is well applied. For virtual GIS to be utilized to manage urban facilities, some functionalities should be provided. One of them is how to manage the huge size of 3D geographic data as compact as possible at the same time providing realistic modeling and visualization. The other one is spatial analysis on urban facilities especially on multistorey buildings. In this paper, the synthetic modeling approach is proposed to model urban facilities realistically from the compact size of GIS data. Geographic features positioned in each storey of a building are also modeled and managed hence they are identified and queried for spatial analysis.

The purpose of this study is to examine a method of traffic congestion data collection using scanned high resolution panchromatic imagery acquired from satellite. The existing traffic monitoring systems including manual and automatic vehicle recording technologies have several limitations in terms of accuracy and spatial coverage ranges. In this paper, traffic information is achieved by frequency analysis techniques from the segmented bridge and/or road images. Especially, the study simulated digital images by fast Fourier transform (FFT) and applied the technique to different two cases in terms of un-clustered vehicles and clustered vehicles.

3D GIS is of increasing interest in the GIS area. The conventional 3D GISs had defects that could not handle the diverse 3D spatial data. However, the application developers want to develop the 3D GIS applications regardless of the formats. In this paper, we present a data provider that has a standard interfaces for the 3D GIS. The developers can use the various 3D data through the data provider without modifying applications. And, this data provider complies with the specification for OLE/COM published by OGC.

The 3D-GIS is one of the emerging issues in GIS and IT fields because it provides new solutions in many application areas today. Most of the research and commercial packages for 3D-GIS can handle only simple features. For many applications, functionalities for handling complex features are necessary. In this paper, we suggest an efficient method for manipulating complex features and applied it to building features in 3D-GIS. The key concept of the applied method is the general features which can be simple features or complex features and is defined by the user. We applied this method to the facility management system supporting floor-based search and analysis.

Geo-features play a key role in object-oriented or feature-based geo-processing system. So the strategy for how-to-manage and how-to-model the geo-features builds the main architecture of the entire system and also supports the efficiency and functionality of the system. Unlike the conventional 2D geo-processing system, geo-features in 3D GIS have lots to be considered to model regarding the efficient manipulation, analysis and visualization. The authors built a set of 3D geo-features, and each geo-feature contains a set of aspatial data and 3D geo-primitives. The 3D geo-primitives contain the fundamental modeling data such as the height of building and the burial depth of gas pipeline. They separated the additional modeling data on the geometry and appearance of the model from the fundamental modeling data to make the table in database more concise and to allow the users more freedom to represent the geo-object. To get the users to build and exchange their own 3D GIS data, the authors devised a file format named VGFF 2.0(Virtual GIS File Format). It is to describe the three dimensional geo-information in XML (eXtensible Markup Language). They also developed the authoring tools for users to create their own 3D geo-features and geo-objects and to edit and save them in VGFF 2.0 format.

In some fish blood vessels, the existence of a NO (nitric oxide) system has been reported. We examined the possibility that this NO system acts as an endothelium-derived relaxing factor (EDRF) in carp aorta using the carp aorta alone and in a combined carp–rat aorta donor-detector system. Use of the typical NO stimulating agent in mammal acetylcholine (ACh) only induced constriction of the carp aorta. This response was not modified by denudation or by NO synthesis inhibition with N -nitro- l -arginine methyl ester. Neither the indirect NO stimulating agents bradykinin and histamine nor the direct NO releasers sodium nitroprusside (SNP) and SIN-1 induced vasorelaxation. Both SNP and ACh elevated the cGMP concentration in rat aorta, but not in carp aorta. In the aorta combination set-up, where carp served as a NO donor and rat aorta served as a NO detector, no relaxation of the rat aorta was observed. The calcium ionophore A23187, a known EDRF producer in mammals, induced relaxation of carp aorta through an endothelium- and cyclooxygenase-dependent mechanism. These results indicate that carp aorta does not produce NO as an EDRF nor does it respond to exogenously supplied NO. The major EDRF in carp is apparently a product(s) of cyclooxygenase metabolism.

The Internet offers opportunities for the distribution of spatial data and the geo-processing of 2D and 2.5D land surface phenomena and topographic data. The demands for detailed 3D application are especially acute. In the present study, a 3-dimensional GIS running on the Internet, is implemented. The system has a part function of 2-dimensional operation and partly 3-dimensional operation and is designed and developed like a lantern operation. The system gives the possibility of making a 3-dimensional GIS running on the Internet and can be used as a standard specification. The main results related to the research scopes can be summarized at component-level and further integrated level: 3D feature format which is composed of aspatial attributes, multimedia-related information, 3D representation information, and 3D geographic primitives, 3D operations which are composed of 3D buffering, near, metric, and Lantern function.

Purpose: To investigate the biologic effects of topical ocular artificial tears used in patients wearing contact lens on in vitro corneal epithelial cells. Methods: The efficacies of the topical artificial tears Iris, Irisplus, Eyemiru contact pure, and Eye2O were evaluated using the MTT and wound healing assays. Cell damage was determined using lactate dehydrogenase (LDH), and the solution ingredients were analyzed. Cellular morphologies were examined by inverted light microscopy and transmission electromicroscopy. Results: Metabolic activity of corneal epithelial cells, as determined by the MTT assay, decreased in the Iris eye drop group, but those of the other groups were similar to that of the control. The LDH titers increased up to one hour after Iris eye drop use, and the increased level was maintained for 24 hours. The other three artificial tears showed similar low LDH titers to that of the control. Cellular migration was not observed, although cellular damage to the corneal epithelial cells, such as chromatin margination and cytoplasmic organelle swelling, was prominent with Iris use. Conclusions: Among four brands of topical artificial tear drops used among patients wearing contact lens, Iris caused markedly more severe damage to cultured human corneal epithelial cells than did Irisplus, Eyemiru contact pure, or Eye2O.

Purpose: To evaluate the therapeutic effect of bevacizumab in treating myopic choroidal neovascularization (CNV). Methods: Medical records of the eyes that underwent intravitreal bevacizumab injection for myopic CNV and were followed up for more than one year were reviewed retrospectively. Best corrected visual acuity (BCVA), foveal thickness in optical coherence tomography and fluorescein angiography were investigated. Results: Twenty eyes of 18 patients were included in the present study. The average age was 41.5 years, average axial length was 28.5 mm, and average refractive error was -11.0 diopters. Visual acuity was maintained in all eyes, and 13 eyes improved by LogMAR 0.3 or more. Visual acuity improved significantly from 0.71 (0.22.0) to 0.40 (0.12.0, p =0.02) at six months and to 0.41 (0.12.0, p =0.03) at one year. Central foveal thickness significantly decreased from 247.0 m to 207.5 m (p =0.03) at six months and to 208.5 m (p =0.04) at one year. Conclusions: Anti-VEGF therapy using bevacizumab for the treatment of myopic CNV was effective in maintaining visual acuity.

Purpose: To evaluate changes in tear secretion and symptoms in patients with mild dry eye syndrome after using Restasis. Methods: From patients diagnosed with mild dry eye syndrome, Restasis was administered to 46 eyes of 23 patients. The clinical parameters and symptoms were checked over a period of six months. The clinical parameters evaluated were the symptoms of dry eye syndrome using an OSDI scoring scale, the Schirmer test, and tear break-up time. Results: Eight male patients and 15 female patients were included in the study. The mean age was 50.5 years. Before treatment, the values for the OSDI score, BUT, and Schirmer test were 32.3, 5.3 mm, and 8.1 seconds, respectively. After treatment, the OSDI score, BUT, and Schirmer test were 22.9, 8.1 mm, and 12.1 seconds at six months, respectively. The subjective parameter (OSDI score) improved two months after treatment (p=0.003), and the objective parameters (BUT, Schirmer test) improved three months after treatment (p=0.03, p=0.04, respectively). Conclusions: In the present study, Restasis increased tear secretion and improved clinical symptoms of patients with mild dry eye.

Cells of an in vitro culture system are not the same as for an in vivo system, metabolically and physiologically; ineffective utilization of nutrients occurs by cells in vitro. Therefore, a simpler approach is needed to examine closely and overcome differences between in vivo and in vitro cells.Recognizing the ineffectiveness of nutrient utilization in vitro, we have constructed, a balanced, fortified high-density medium based on RPMI 1640 medium previously optimized for relatively low-density cell culture. The high-density medium was used to cultivate a hybridoma line in a batch spinner flask culture. In this fortified medium, a hybridoma cell line 2c3.1 was cultivated to near 1 x 10(7) cells/mL in batch suspension culture. During the culture, glucose, glutamine, and 10 essential amino acids of concentrations five times richer than normal in the medium were almost thoroughly consumed. Combined analysis of these consumption profiles reveals that the balanced, fortified nutrient supply contributes much to cellular activity to overcome the limitations of in vitro cellular growth. Intermediate metabolites, such as ammonium ion and lactic acid, were produced over concentrations reported until now to be inhibitory. This observation suggests that the major conclusive factor against cellular growth over the critical cell density is not so-called inhibitory metabolites. As a result of the high-density culture, 5-8 times higher production of a monoclonal antibody for hepatitis B surface antigen (anti-HBs) was obtained.Active cellular consumption of all the essential nutrients and the corresponding production of MAb strongly support the potential of our approach to overcome the growth limitation of cells in vitro and to obtain high-density hybridoma cell culture.

To maintain a constant specific growth rate for a recombinantS.cerevisiae in fed-batch, the medium feeding rate has been controlled with respect to the hourly calculated glucose uptake rate. The recombinant yeast producing HBsAg showed the exponential production trend in proportion to the exponential cell growth. Total cell yield in fed-batch was about 0.402 g cells/g glucose, and HBsAg was produced about ten times more than in batch. Decrease of growth rate by HBsAg produced was not shown.

In the light of recent knowledge on a complex of diseases caused by a new group of viruses, arenaviruses, virological studies largely directed toward small field mammals were undertaken during 1973-1974 aiming at etiological clarification of Korean hemorrhagic nephrosonephritis (KHNN). Specimens were collected in an endemic area of KHNN located north to northeast of Seoul. Virus isolation tests with 299 urine specimens and 131 mite pools recovered from small mammals and 14 acute stage sera from typical cases yielded negative results. Complement-fixation (CF) tests failed to detect antibodies against the antigens of Congo, lymphocytic choriomeningitis (LCM), Tacaribe, and Pichinde viruses among 366 small mammal sera. In addition, CF tests of 59 of the above sera against Apoi and Lassa virus antigens were negative. The results do not support the likelihood of an arenavirus being transmitted among Korean small field mammals, the overwhelming majority of which were Apodemus agrarius. A hypothesis that KHNN is caused by a virus of small field mammal origin was not proved within the technical limit of relatively unsophisticated methods employed herein.