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A probe array with nano-scale tips, integrated into a micro-fluidic channel was developed for the capture and lysing of small number of vaccinia virus particles using dielectrophoresis. The nano-scale probe array was fabricated in Silicon on Insulator (SOI) wafers, and sharpened with repeated oxidation steps. The gap between each probe ranged from 100 nm to 1.5 microm depending on fabrication parameters. The probe array was used to capture vaccinia virus using positive dielectrophoresis (DEP) from a flow within the microfluidic channel, and then the same probe array was used to apply high electric field to lyse the virus particles. It was shown that under electric field strengths of about 10(7)V/m, the permeability of ethidium bromide into the vaccinia virus particles was increased. Upon SEM analysis, the particles were found to be damaged and exhibited tubules networks, indicating disintegration of the virus outer layer. In addition, elongated strands of DNA were clearly observed on the chip surface after the application of the high electric field, demonstrating the possibility of electrical lysis of virus particles.

Recent advances in mechanobiology have accumulated strong evidence showing close correlations between the physiological conditions and mechanical properties of cells. In this paper, a novel optomechanical technique to characterize the stiffness of single adherent cells attached on a substrate is reported. The oscillation in a cell's height on a vertically vibrating reflective substrate is measured with a laser Doppler vibrometer as apparent changes in the phase of the measured velocity. This apparent phase shift and the height oscillation are shown to be affected by the mechanical properties of human colorectal adenocarcinoma cells (HT-29). The reported optomechanical technique can provide high-throughput stiffness measurement of single adherent cells over time with minimal perturbation.

Phase-change nanowires (NWs) have emerged as critical materials for fast-switching nonvolatile memory devices. In this study, we synthesized a series of mGeTe·Bi2Te3 (GBT) pseudobinary alloy NWs-Ge3Bi2Te6 (m = 3), Ge4Bi2Te7 (m = 4), Ge5Bi2Te8 (m = 5), Ge6Bi2Te9 (m = 6), and Ge8Bi2Te11 (m = 8)-and investigated their composition-dependent thermal stabilities and electrical properties. As m decreases, the phase of the NWs evolves from the cubic (C) to the hexagonal (H) phase, which produces unique superlattice structures that consist of periodic 2.2-3.8 nm slabs for m = 3-8. In situ temperature-dependent transmission electron microscopy reveals the higher thermal stability of the compositions with lower m values, and a phase transition from the H phase into the single-crystalline C phase at high temperatures (400 °C). First-principles calculations, performed for the superlattice structures (m = 1-8) of GBT and mGeTe·Sb2Te3 (GST), show an increasing stability of the H phase (versus the C phase) with decreasing m; the difference in stability being more marked for GBT than for GST. The calculations explain remarkably the phase evolution of the GBT and GST NWs as well as the composition-dependent thermal stabilities. Measurement of the current-voltage curves for individual GBT NWs shows that the resistivity is in the range 3-25 mΩ·cm, and the resistivity of the H phase is lower than that of the C phase, which has been supported by the calculations.

Semiconductor alloy nanowires (NWs) have recently attracted considerable attention for applications in optoelectronic nanodevices because of many notable properties, including band gap tunability. Zinc phosphide (Zn3P2) and zinc arsenide (Zn3As2) belong to a unique pseudocubic tetragonal system, but their solid solution has rarely been studied. Here In this study, we synthesized composition-tuned Zn3(P1-xAsx)2 NWs with different crystal structures by controlling the growth conditions during chemical vapor deposition. A first type of synthesized NWs were single-crystalline and grew uniformly along the [110] direction (in a cubic unit cell) over the entire compositional range (0 ≤ x ≤ 1) explored. The use of an indium source enabled the growth of a second type of NWs, with remarkable cubic-hexagonal polytypic twinned superlattice and bicrystalline structures. The growth direction of the Zn3P2 and Zn3As2 NWs was also switched to [111] and [112], respectively. These structural changes are attributable to the Zn-depleted indium catalytic nanoparticles which favor the growth of hexagonal phases. The formation of a solid solution at all compositions allowed the continuous tuning of the band gap (1.0-1.5 eV). Photocurrent measurements were performed on individual NWs by fabricating photodetector devices; the single-crystalline NWs with [110] growth direction exhibit a higher photoconversion efficiency compared to the twinned crystalline NWs with [111] or [112] growth direction.

The purpose of this study was to assess adequately equipped with convenience facilities for the disabled in 160 healthcare institutions in Jongno district, Seoul. Healthcare institutions were equipped an average of 3.7 facilities out of 10. General hospitals had an average of 5.0 facilities, which was higher than an average of 3.6 facilities for private clinics (p

This study aimed to measure the disability weights for the Korean Burden of Disease study, and to compare them with those adopted in the Australian study to examine the validity and describe the distinctive features.The standardized valuation protocol was developed from the Global Burden of Disease (GBD) study and the Dutch Disability Weights study. Disability weights were measured for 123 diseases of the Korean version of Disease Classification by three panels of 10 medical doctors each. Then, overall distribution, correlation coefficients, difference by each disease, and mean of differences by disease group were analyzed for comparison of disability weights between the Korean and Australian studies.Korean disability weights ranged from 0.037 to 0.927. While the rank correlation coefficient was moderate to high (rs=0.68), Korean disability weights were higher than the corresponding Australian ones in 79.7% of the 118 diseases. Of these, war, leprosy, and most injuries showed the biggest differences. On the contrary, many infectious and parasitic diseases comprised the greater part of diseases of which Korean disability weights were lower. The mean of the differences was the highest in injuries of GBD disease groups, and in cardiovascular disease, injuries, and malignant neoplasm of the Korean disease category.Korean disability weights were found to be valid on the basis of overall distribution pattern and correlation, and are expected to be used as basic data for broadening the scope of burden of disease study. However, some distinctive features still remain to be explored in following studies.

This paper presents (111) nano tips made using (111) single crystalline silicon. Many research efforts have reported on the fabrication methods of micro and nano tips in silicon. Most of the developed fabrication methods are based on (100) or (110) silicon. However, (111) silicon will give the sharpest {111}-bounded nano tips, and in addition, (111) silicon has the best mechanical properties compared with other types of silicon. In this paper, we use (111) silicon wafers to fabricate two type of nano tip. One type is the sharpest nano tip that can be fabricated by using only {111} silicon planes. The other type is a high aspect ratio nano tip, which is composed of one {111} plane and two vertical passivation planes. In the first case, the tip height is 5 μm and the total cone angle of the tip is 54.7°, which represents the sharpest angle for a nano tip bounded only by {111} planes on silicon. In the second case, the nano tip height is 15 μm, and the aspect ratio is greater than 3:1. The cone angle of the nano tip is only 19.5°. The tip radius is less then 10 nm, which is of the sharpest {111}-bound, single-crystalline-silicon nano tips.

SUMMARY Disease coding errors in claims data can cause serious problems for financing, reimbursement systems, public health surveillance and health research. This study analysed a government intervention to improve coding accuracy of health care organizations in South Korea. The intervention was implemented in 1997 by 226 organizations that had submitted erroneous claims in 1996 for five selected diseases. In 1998, 94% of these organizations eliminated coding errors for these diseases. Those organizations least responsive to the intervention were tertiary hospitals, those publicly owned, and those with other complex organizational characteristics. Overall, this simple intervention appeared extremely effective, and wider adoption of such techniques should be explored. Copyright # 2003 John Wiley & Sons, Ltd.

Multicomponent nanowires (NWs) are of great interest for integrated nanoscale optoelectronic devices owing to their widely tunable band gaps. In this study, we synthesize a series of (GaP)(1-x)(ZnS)(x) (0 ≤ x ≤ 1) pseudobinary alloy NWs using the vapor transport method. Compositional tuning results in the phase evolution from the zinc blende (ZB) (x0.4) to the wurtzite (WZ) phase (x0.7). A coexistence of ZB and WZ phases (x = 0.4-0.7) is also observed. In the intermediate phase coexistence range, a core-shell structure is produced with a composition of x = 0.4 and 0.7 for the core and shell, respectively. The band gap (2.4-3.7 eV) increases nonlinearly with increasing x, showing a significant bowing phenomenon. The phase evolution leads to enhanced photoluminescence emission. Strikingly, the photoluminescence spectrum shows a blue-shift (70 meV for x = 0.9) with increasing excitation power, and a wavelength-dependent decay time. Based on the photoluminescence data, we propose a type-II pseudobinary heterojunction band structure for the single-crystalline WZ phase ZnS-rich NWs. The slight incorporation of GaP into the ZnS induces a higher photocurrent and excellent photocurrent stability, which opens up a new strategy for enhancing the performance of photodetectors.

This paper presents a methodology that can be used in earthquake design that encourages the use of dampers and other “high tech” structural elements. It also encourages the performance of a nonlinear dynamic analysis of buildings that are being evaluated and strengthened. The methodology uses equations from the Bayesian area of Structural Reliability theory and thus has a scientific foundation. The Los Angeles Tall Buildings Structural Design Council (LATBSDC) has developed a design procedure for the earthquake loading on tall buildings that requires three important items not typically required for tall building design; see the paper entitled “An Alternative Procedure for Seismic Analysis and Design of Tall Buildings” by F. Naeim, L.D. Carpenter, T. Ghodsi, G.C. Hart, M. Lew, M. Mehrain, T. Sabol, and J. Wallace. The required items are: (1) Peer Review Panel (2) Nonlinear time history analysis for ultimate (strength) performance (3) Service Level evaluation of performance Therefore, what is presented in this paper starts with these requirements as a given and requires that capacity reduction factors used for design be project specific and transparency derived and supported. Also, since the use of a structural analysis demand and capacity models are at the core of such analyses, this paper especially focus on how existing test data can be directly used with professional experience in deriving the Expected Value and Standard Deviation of the Capacity equation. For a given value of Reliability Index, the structural engineer must determine the Expected Value of Capacity and Demand, and also their Coefficients of Variation for the capacity and demand random variables. The calculation for the Prescribed Load Capacity Reduction Factors for a set value of the Reliability Index can be significantly reduced with a reduction in the Uncertainty in Capacity and / or a reduction in Uncertainty in Demand. An important part of this paper is how to benefit from the knowledge and experience of the structural engineer of record and peer reviewers; previous test data in the published literature; and also more refined structural analysis computer models in estimating the Coefficients of Variation of Capacity and Demand. The Bayesian part of this paper recognizes that both the Expected Value and Standard Deviation of the Capacity and Demand cannot be estimated by the Structural Engineer with certainty and therefore they are also random variables with their own Expected Value and Standard Deviation. In a previous paper, published in a Wiley journal, entitled “Performance Based Evaluation and Strengthening of Tall Buildings in the Los Angeles region using Bayesian Structural Reliability” by G.C. Hart, J.P. Conte, K. Park, B. Ellingwood, K.K.F. Wong, we presented the methodology for estimating the Expected Value and Coefficient of Variation of Capacity or Demand if they were Normal random variables. In this paper we will present the corresponding methodology when the Capacity and Demand are Log-Normal random variables. Also, structural engineering examples will show the use of the equations and their importance in performance based design.

This paper presents a case study where an existing eight story Los Angeles reinforced concrete shear wall building is strengthened to the same level of safety against collapse as if the building were rebuilt as a new building. The goal stated in probabilistic words is to provide the same value of Central Safety Factor for the Collapse Limit State as a new building using Structural Reliability theory. The paper will describe how we incorporated in a direct manner the uncertainty reduction in capacity and demand associated with the use of carbon fiber reinforcing of the shear walls and also the use of a nonlinear time history analysis in the analysis as part of the rehabilitation work. The structural reliability foundation for this paper is presented in two 2012 Wiley journal papers which are “Structural Reliability for Structural Engineers Evaluating and Strengthening a Tall Buildings” by G.C. Hart, J.P. Conte, K. Park, D. Reyes, S.C. Huang, and “Performance Based Evaluation and Strengthening of Tall Buildings in the Los Angeles region using Bayesian Structural Reliability” by G.C. Hart, J.P. Conte, K. Park, B. Ellingwood, K.K.F. Wong. In the rehabilitation part of this paper, we describe how different levels of field investigation and also layers of carbon fiber reinforcing impact the value of the Central Safety Factor. We also consider the impact of more earthquake strong motion time history records that can be provided by the geotechnical engineer (e.g. 3, 5, 10, etc.) and then used in our nonlinear analysis phase of work. In addition to this we also show how component cyclic testing at a university type laboratory can be directly incorporated into the calculation of the Central Safety Factor. This includes the Expected Value and Coefficient of Variation of the laboratory test data. What we will then present in this paper is the design development for a new reinforced concrete shear wall building using the 2012 ICC and ASCE 7-10. The new building design will have the same shear wall locations. A direct comparison will now be able to be made between new steel detailing requirements and from an important structural reliability perspective the Expected Value and Coefficient of Variation of all random variables in the new and rehabilitation design equations. Also, in the new building design, we do a similar impact analysis for the Central Safety Factor associated with such analysis items as the complexity of the structural analysis model and such construction items as scope and number of field investigation during the construction phase. We also show we can incorporate in the calculation of the Central Safety Factor of existing structural component testing (both cyclic and non-cyclic).

Scaling-down of phase change materials to a nanowire (NW) geometry is critical to a fast switching speed of nonvolatile memory devices. Herein, we report novel composition-phase-tuned GeSbTe NWs, synthesized by a chemical vapor transport method, which guarantees promising applications in the field of nanoscale electric devices. As the Sb content increased, they showed a distinctive rhombohedral-cubic-rhombohedral phase evolution. Remarkable superlattice structures were identified for the Ge(8)Sb(2)Te(11), Ge(3)Sb(2)Te(6), Ge(3)Sb(8)Te(6), and Ge(2)Sb(7)Te(4) NWs. The coexisting cubic-rhombohedral phase Ge(3)Sb(2)Te(6) NWs exhibited an exclusively uniform superlattice structure consisting of 2.2 nm period slabs. The rhombohedral phase Ge(3)Sb(8)Te(6) and Ge(2)Sb(7)Te(4) NWs adopted an innovative structure; 3Sb(2) layers intercalated the Ge(3)Sb(2)Te(6) and Ge(2)Sb(1)Te(4) domains, respectively, producing 3.4 and 2.7 nm period slabs. The current-voltage measurement of the individual NW revealed that the vacancy layers of Ge(8)Sb(2)Te(11) and Ge(3)Sb(2)Te(6) decreased the electrical conductivity.

The quest to 'forward-engineer' and fabricate biological machines remains a grand challenge. Towards this end, we have fabricated locomotive "bio-bots" from hydrogels and cardiomyocytes using a 3D printer. The multi-material bio-bot consisted of a 'biological bimorph' cantilever structure as the actuator to power the bio-bot, and a base structure to define the asymmetric shape for locomotion. The cantilever structure was seeded with a sheet of contractile cardiomyocytes. We evaluated the locomotive mechanisms of several designs of bio-bots by changing the cantilever thickness. The bio-bot that demonstrated the most efficient mechanism of locomotion maximized the use of contractile forces for overcoming friction of the supporting leg, while preventing backward movement of the actuating leg upon relaxation. The maximum recorded velocity of the bio-bot was ~236 µm s(-1), with an average displacement per power stroke of ~354 µm and average beating frequency of ~1.5 Hz.

To develop the advanced electronic devices, the surface/interface of each component must be carefully considered. Here, we investigate the electrical properties of metal-semiconductor nanoscale junction using conductive atomic force microscopy (C-AFM). Single-crystalline CdS, CdSe, and ZnO one-dimensional nanostructures are synthesized via chemical vapor transport, and individual nanobelts (or nanowires) are used to fabricate nanojunction electrodes. The current-voltage (I -V) curves are obtained by placing a C-AFM metal (PtIr) tip as a movable contact on the nanobelt (or nanowire), and often exhibit a resistive switching behavior that is rationalized by the Schottky (high resistance state) and ohmic (low resistance state) contacts between the metal and semiconductor. We obtain the Schottky barrier height and the ideality factor through fitting analysis of the I-V curves. The present nanojunction devices exhibit a lower Schottky barrier height and a higher ideality factor than those of the bulk materials, which is consistent with the findings of previous works on nanostructures. It is shown that C-AFM is a powerful tool for characterization of the Schottky contact of conducting channels between semiconductor nanostructures and metal electrodes.

Hydrodynamic loading greatly affects resonant characteristic of microfabricated structures immersed in a viscous fluid. In this letter, we demonstrate a technique to measure hydrodynamic loading on a MEMS resonator in a broad range of actuation frequency. The extracted hydrodynamic loading is in a good agreement with an analytical solution of an oscillating sphere, and a highly accurate model is developed for the hydrodynamic loading of the resonator. The developed technique can directly characterize the hydrodynamic loading of a microstructure with an arbitrary geometry and will facilitate the optimization of MEMS devices and AFM probes operating in a viscous fluid.

We examined the hydrodynamic loading of vertically resonating microfabricated plates immersed in liquids with different viscosities. The planar structures were patterned with focused ion beam, perforating various shapes with identical area but varying perimeters. The hydrodynamic loading of various geometries was characterized from resonant frequency and quality factor. In water, the damping increased linearly with the perimeter at 45.4 × 10−3 Ns/m2, until the perforation’s radius was 123% ± 13% of the depth of penetration of fluid’s oscillation. The added mass effect decreased with perforations and recovered to the level of un-perforated structures when the perforation’s radius became smaller than the depth of penetration.

MEMS-based resonant mass sensors can be sensitive tools to measure the physical properties of cells such as their mass. We recently developed an array of sensors that have a uniform mass sensitivity for measuring the stiffness and the long-term growth rate of adherent human colon adenocarcinoma cells (HT-29) [1]. We demonstrated that for these adherent single cells, the cell growth rate increases with call mass, i.e. larger cells grow faster. The finding points to the fact that additional cell-size control mechanisms might be required for cell size homeostasis over generations and that growth rate is determined by the amount of the ribosomal machinery, which doubles during the cell cycle. Here, we expand our studies by presenting an additional sensor design with further optimization for higher uniformity of the mass sensitivity based on a detailed numerical analysis. We also demonstrate that MEMS resonant mass sensors can be used to measure physical changes in apoptotic cells. HT29 were treated with staurosporine, a potent drug that induces cellular apoptosis. Through Laser Doppler Vibrometery (LDV), we measured changes in the cells' apparent mass, and correlated these changes with optical images using dark field microscopy. Such real-time mass measurements of individual cells coupled with optical imaging can be a powerful tool to understand the physiological processes of cell growth and apoptosis.

Microfluidic devices have advanced cell studies by providing a dynamic fluidic environment on the scale of the cell for studying, manipulating, sorting and counting cells. However, manipulating the cell within the fluidic domain remains a challenge and requires complicated fabrication protocols for forming valves and electrodes, or demands specialty equipment like optical tweezers. Here, we demonstrate that conventional printed circuit boards (PCB) can be used for the non-contact manipulation of cells by employing dielectrophoresis (DEP) for bead and cell manipulation in laminar flow fields for bioactuation, and for cell and bead separation in multichannel microfluidic devices. First, we present the protocol for assembling the DEP electrodes and microfluidic devices, and preparing the cells for DEP. Then, we characterize the DEP operation with polystyrene beads. Lastly, we show representative results of bead and cell separation in a multichannel microfluidic device. In summary, DEP is an effective method for manipulating particles (beads or cells) within microfluidic devices.

MEMS-based resonant mass sensors have been extensively studied as biological and chemical sensor. Most of these sensors have utilized a cantilever structure, and these cantilever resonant mass sensors have a spatially non-uniform mass sensitivity. In this study, a silicon MEMS-based resonant mass sensor with a spatially uniform mass sensitivity is developed. The sensor is composed of a platform for the target attachment and four half-folded springs. The novel structure generates a vertical displacement of the platform, which leads to the uniform mass sensitivity. The extracted mass of a same bead on different places shows a standard deviation of 1.4%.

The size of a cell is a fundamental physiological property and is closely regulated by various environmental and genetic factors. Optical or confocal microscopy can be used to measure the dimensions of adherent cells, and Coulter counter or flow cytometry ( forward scattering light intensity) can be used to estimate the volume of single cells in a flow. Although these methods could be used to obtain the mass of single live cells, no method suitable for directly measuring the mass of single adherent cells without detaching them from the surface is currently available. We report the design, fabrication, and testing of 'living cantilever arrays', an approach to measure the mass of single adherent live cells in fluid using silicon cantilever mass sensor. HeLa cells were injected into microfluidic channels with a linear array of functionalized silicon cantilevers and the cells were subsequently captured on the cantilevers with positive dielectrophoresis. The captured cells were then cultured on the cantilevers in a microfluidic environment and the resonant frequencies of the cantilevers were measured. The mass of a single HeLa cell was extracted from the resonance frequency shift of the cantilever and was found to be close to the mass value calculated from the cell density from the literature and the cell volume obtained from confocal microscopy. This approach can provide a new method for mass measurement of a single adherent cell in its physiological condition in a non-invasive manner, as well as optical observations of the same cell. We believe this technology would be very valuable for single cell time-course studies of adherent live cells.

This study was conducted to evaluate the public's awareness of the importance of hand washing and to compare perceptions on the habit of hand washing with actual hand washing behavior.Data were collected by observing 2,800 participants washing their hands after using public restrooms in seven cities nationwide and by surveying 1,000 respondents (age14 years) through telephone interviews using a structured questionnaire.Although 94% of the survey respondents claimed to mostly or always wash their hands after using public restrooms, only 63.4% of the observed participants did wash their hands after using public restrooms. Significant factors related to increased adherence to hand washing were female gender, approximate ages of 20 to 39 years by their appearance, and the presence of other people from the observation. About 79% of the survey respondents always washed their hands after using bathrooms at home, 73% washed their hands before handling food, and 67% washed their hands upon returning to their home. However, 93.2% and 86.3% of the survey respondents did not wash their hands after coughing or sneezing and after handling money, respectively. Although most of the survey respondents (77.6%) were aware that hand washing is helpful in preventing communicable diseases, 39.6% of the survey respondents did not do so because they were 'not accustomed' to washing their hands and 30.2% thought that washing their hands is 'annoying'.This is the first comprehensive report on hand washing behavior and awareness of the general population in Korea. The result of this study in terms of individual behavior and awareness of hand washing are comparable with similar studies conducted in other countries. However adherence to hand washing is still low and needs to be increased. The results of this study can be used as a baseline in setting up strategies and activities to promote adherence to hand washing.

This paper presents a novel fabrication process for ultra-sharp nano tips on cantilevers with the radius of curvature of less than 10 nm using an (111) single crystalline silicon wafer. The nano tip height 15 /spl mu/m, and the aspect ratio is greater than 3:1. The cone angle of the tip is 19.5/spl deg/. Fabrication process is based on newly obtained etch characteristic data on silicon (111) and the sacrificial bulk micromachining (SBM) technology. The developed fabrication process is simple and robust, and well suited for ultra-sharp, high-aspect ratio nano tips on cantilevers.

The World Health Organisation established the Roll Back Malaria (RBM) strategy to reduce the global burden of malaria in 1998. A set of RBM indicators will not be suitable to the Republic of Korea due to the differences of the epidemiological and socio-cultural situation. Therefore, we have developed a framework and indicators for monitoring the outcomes and impact of the national malaria eradication programme that are appropriate for the situation in Korea. We reviewed the existing data in the national malaria eradication programme. We adopted general principles in developing a monitoring framework and indicators for monitoring RBM. Monitoring areas were recombined components and content that included the project plan, training health personnel, health education and public information, supply for manpower, equipment and materials, disease control, information system, supervision, community participation, intersectoral collaboration within practical guidelines for the national malaria eradication programme along with malaria control and RBM strategy of WHO. Twenty one monitoring areas were selected that identified critical areas for the national malaria eradication programme. Fifteen indicators of ten categories are proposed for use by the national malaria eradication programme in Korea. Asia Pac J Public Health 2003; 15(1): 44-49.

Particle manipulation based on dielectrophoresis (DEP) can be a versatile and useful tool in lab-on-chip systems for a wide range of cell patterning and tissue engineering applications. Even though there are extensive reports on the use of DEP for cell patterning applications, the development of approaches that make DEP even more affordable and common place is still desirable. In this study, we present the use of interdigitated electrodes on a printed circuit board (PCB) that can be reused to manipulate and position HeLa cells and polystyrene particles over 100 microm thick glass cover slips using DEP. An open-well or a closed microfluidic channel, both made of PDMS, was placed on the glass coverslip, which was then placed directly over the PCB. An AC voltage was applied to the electrodes on the PCB to induce DEP on the particles through the thin glass coverslip. The HeLa cells patterned with DEP were subsequently grown to confirm the lack of any adverse affects from the electric fields. This alternative and reusable platform for DEP particle manipulation can provide a convenient and rapid method for prototyping a DEP-based lab-on-chip system, cost-sensitive lab-on-chip applications, and a wide range of tissue engineering applications.

not Available.

Changing patterns of the reemerging Plasmodium vivax malaria in the Republic of Korea (South Korea) during the period 1993 to 2005 are briefly analyzed with emphasis on the control measures used and the effects of meteorological and entomological factors. Data were obtained from the Communicable Diseases Monthly Reports published by the Korea Center for Disease Control and Prevention, and webpages of World Health Organization and United Nations. Meteorological data of Kangwon-do (Province) were obtained from local weather stations. After its first reemergence in 1993, the prevalence of malaria increased exponentially, peaking in 2000, and then decreased. In total, 21,419 cases were reported between 1993 and 2005 in South Korea. In North Korea, a total of 916,225 cases were reported between 1999 and 2004. The occurrence of malaria in high risk areas of South Korea was significantly (P < 0.05) correlated with the mosquito population but not with temperature and rainfall. Control programs, including early case detection and treatment, mass chemoprophylaxis of soldiers, and international financial aids to North Korea for malaria control have been instituted. The situation of the reemerging vivax malaria in the Republic of Korea is remarkably improving during the recent years, at least in part, due to the control activities undertaken in South and North Korea.

Since the inception of the National Tuberculosis Control Program in 1962, the incidence of tuberculosis and its associated mortality has declined dramatically due to effective anti-tuberculosis drugs and a systematic control program. The prevalence of radiographically active tuberculosis has fallen from 5.1% in 1965 to 1.0% in 1995. However, tuberculosis is still a major problem, as the mortality rate is still higher compared to other developed countries. Furthermore, tuberculosis is currently re-emerging in HIV/AIDS epidemic countries. In order to lower the tuberculosis death rate to the levels of developed countries, the tuberculosis control efforts in private healthcare institutions and the national tuberculosis control program in the public sector, need to work together more effectively and efficiently. In this paper, the quthor reviewed the current situation regarding tuberculosis management in private healthcare institutions of Korea based on the literature and the National Health Insurance Claim data, and the future tasks of tuberculosis management are suggested.