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Nicotinamide adenine dinucleotide (NAD)+ serves as a crucial coenzyme in numerous essential biological reactions, and its cellular availability relies on the activity of the nicotinamide phosphoribosyltransferase (NAMPT)-catalyzed salvage pathway. Here we show that treatment with saturated fatty acids activates the NAD+ salvage pathway in hypothalamic astrocytes. Furthermore, inhibition of this pathway mitigates hypothalamic inflammation and attenuates the development of obesity in male mice fed a high-fat diet (HFD). Mechanistically, CD38 functions downstream of the NAD+ salvage pathway in hypothalamic astrocytes burdened with excess fat. The activation of the astrocytic NAMPT–NAD+–CD38 axis in response to fat overload induces proinflammatory responses in the hypothalamus. It also leads to aberrantly activated basal Ca2+ signals and compromised Ca2+ responses to metabolic hormones such as insulin, leptin, and glucagon-like peptide 1, ultimately resulting in dysfunctional hypothalamic astrocytes. Our findings highlight the significant contribution of the hypothalamic astrocytic NAD+ salvage pathway, along with its downstream CD38, to HFD-induced obesity.The cellular levels of the critical coenzyme nicotinamide adenine dinucleotide (NAD)+ depend on its salvage pathway. Here, the authors show that the NAD+ salvage pathway in hypothalamic astrocytes is activated to promote obesity in high fat diet-fed mice. [ABSTRACT FROM AUTHOR]

Nicotinamide adenine dinucleotide (NAD+) is an essential cofactor of critical enzymes including protein deacetylase sirtuins/SIRTs and its levels in mammalian cells rely on the nicotinamide phosphoribosyltransferase (NAMPT)-mediated salvage pathway. Intracellular NAMPT (iNAMPT) is secreted and found in the blood as extracellular NAMPT (eNAMPT). In the liver, the iNAMPT−NAD+ axis oscillates in a circadian manner and regulates the cellular clockwork. Here we show that the hypothalamic NAD+ levels show a distinct circadian fluctuation with a nocturnal rise in lean mice. This rhythm is in phase with that of plasma eNAMPT levels but not with that of hypothalamic iNAMPT levels. Chemical and genetic blockade of eNAMPT profoundly inhibit the nighttime elevations in hypothalamic NAD+ levels as well as those in locomotor activity (LMA) and energy expenditure (EE). Conversely, elevation of plasma eNAMPT by NAMPT administration increases hypothalamic NAD+ levels and stimulates LMA and EE via the hypothalamic NAD+−SIRT−FOXO1−melanocortin pathway. Notably, obese animals display a markedly blunted circadian oscillation in blood eNAMPT−hypothalamic NAD+−FOXO1 axis as well as LMA and EE. Our findings indicate that the eNAMPT regulation of hypothalamic NAD+ biosynthesis underlies circadian physiology and that this system can be significantly disrupted by obesity. Nicotinamide phosphoribosyl transferase (NAMPT) is a critical regulator of cellular nicotinamide adenine dinucleotide (NAD)+ levels. Here, the authors show that blood NAMPT contributes to the circadian rhythm generation of locomotor activity and energy expenditure by regulating hypothalamic NAD+ levels. [ABSTRACT FROM AUTHOR]

This study investigates the production technology of black burnished pottery from the royal fortress and tombs in the Hanseong period of Baekje (fourth to fifth century AD), Ancient Korea. This pottery can be classified into two types based on the form of the black layer on the cross-section: a thick, progressing layer (smudging black (SB)-type) and a thin and fine layer on the surface (coating black (CB)-type). Raman spectroscopy detected combustion carbon with an amorphous structure in the black portion of the SB-type (surface/core/inner surface) and CB-type (outer surface/inner surface). Micro Fourier transform infrared spectroscopy (micro-FT-IR) and time-of-flight secondary-ion mass spectrometry (ToF–SIMS) results showed that urushiol, the main component of lacquer, was found on the outer surface of pottery. Results showed that SB-type is a pottery in which combustion carbon is smudged inside the pottery using plant ash, and the outermost surface is lacquered for gloss. In CB-type pottery, a thin combustion carbon layer is formed using a lacquer after firing the pottery body. X-ray diffraction studies showed that most of the pottery may have been fired at 550–850 °C. This study identified the colouring component of black pottery and presented examples of the lacquer usage in pottery. [ABSTRACT FROM AUTHOR]

Among the components of the blood–brain barrier (BBB), endothelial cells (ECs) play an important role in supplying limited materials, especially glucose, to the brain. However, the mechanism by which glucose is metabolized in brain ECs is still elusive. To address this topic, we assessed the metabolic signature of glucose utilization using live-cell metabolic assays and liquid chromatography–tandem mass spectrometry metabolomic analysis. We found that brain ECs are highly dependent on aerobic glycolysis, generating lactate as its final product with minimal consumption of glucose. Glucose treatment decreased the oxygen consumption rate in a dose-dependent manner, indicating the Crabtree effect. Moreover, when glycolysis was inhibited, brain ECs showed impaired permeability to molecules utilizing transcellular pathway. In addition, we found that the blockade of glycolysis in mouse brain with 2-deoxyglucose administration resulted in decreased transcellular permeability of the BBB. In conclusion, utilizing glycolysis in brain ECs has critical roles in the maintenance and permeability of the BBB. Overall, we could conclude that brain ECs are highly glycolytic, and their energy can be used to maintain the transcellular permeability of the BBB. [ABSTRACT FROM AUTHOR]

Understanding the long- and short-term weathering features according to rock type is very important for maintaining the original form of stone heritages. In this study, the material characteristics of a deteriorated five-story stone pagoda were compared with those of fresh rocks from its quarrying site at nearby Geumgolsan Mountain, Korea, to diagnose the degree of damage and develop a comprehensive interpretation of the weathering mechanism. The stone pagoda was built from lithic tuff comprising pumice and phenocrysts such as quartz, K-feldspar, plagioclase, and mica based on plagioclase substrates; the mineralogical and geochemical characteristics are similar to those of the fresh rocks. The lithic tuff of the stone pagoda demonstrated a low ultrasonic velocity of 2863 m/s and a high water absorption rate and porosity of 9.5% and 19.2%, respectively, which are poorer than the physical properties of the fresh rocks (i.e., ultrasonic velocity of 3336 m/s, water absorption rate of 8.65%, and porosity of 17.83%). The lithological characteristics and physical properties demonstrated a considerable influence on the weathering and stability of the stone pagoda. In particular, fragments of relatively weak pumice detached from the original rock to form cavities of various sizes. These cavities introduced moisture within the rock, which produced oxides and hydroxides of iron and manganese. In addition, contaminants such as dust, salt crystals, clay minerals, and microorganisms adhering to the surface of the stone pagoda accelerated its physical, chemical, and biological weathering. The results of this study will be important for realizing the stable and long-term conservation of the five-story stone pagoda at Geumgolsan Mountain. [ABSTRACT FROM AUTHOR]

The Hong Nang Sida temple with significant historical value was designated as a UNESCO world cultural heritage. However, most parts of the main temple were destroyed, and being neglected for a long time. Some remained building structures also have been influenced on asymmetric load, it causes various types of damage including imbalance problem. Accordingly, reasonable conservation treatment and proper restoration processes are required. The stone material of the main temple in Hong Nang Sida is made with sandstone and siltstone, and by assuming that they were extracted from nearby Mt. Phou Kao. Specimens were collected from Mt. Phou Kao, Douangdy and Vat Chompet quarries to review the homogeneity with the stones in Hong Nang Sida temple. Also, by analyzing the sandstone used to restore the Vat Phou temples located around the Hong Nang Sida temple, it was examined whether it could be used for restoration of the Hong Nang Sida temple. The study on the homogeneity of stones revealed that it would be the most desirable to use rocks from Mt. Phou Kao as alternative stones for restoration of the main temple. It has different lithological and geochemical characteristics from the restoration stone of the Vat Phou temple. However, as Mt. Phou Kao was designated as world cultural heritage protection area, it is hard to get sufficient amount of alternative stones for restoration. Thus, it is proper to secure alternative stones from Douangdy and Vat Chompet quarries, considering the geochemical homogeneity, color and sedimentary structure as well as procurement possibility. [ABSTRACT FROM AUTHOR]

The White-Robed Water-Moon Avalokiteshvara painting displayed on the rear wall of Daegwangbojeon (main hall) in Magoksa temple, is one of the representative Buddhist paintings in the late nineteenth century of Korea, and a valuable resource for understanding the coloring techniques and characteristics of Buddhist paintings in terms of expression and description in landscape painting. In this painting, the contours and colored surface remain undamaged, but blistering and exfoliation appear on some pigment layers. Furthermore, the partial decomposition of wooden materials due to wood-decay fungi and insect damage were found on the rear wall requiring proper treatment for long-term conservation. As the results of chromaticity and P-XRF analysis regarding the color pigment layer of the painting, the pigments were classified into ten types. The results suggest that the colors other than blue, green, yellow, red, black, and white were prepared by mixing two or more pigments. The types of pigments according to colors, were determined as traditional pigments with azurite; emerald green or clinoatacamite; 0 massicot; minium or hematite; Chinese ink; and kaolin, white lead, and gypsum, respectively. Violet and pink colors were assumed to have been prepared by mixing white with blue and red. In most of these pigments, small amounts of synthetic compositions from the modern era were detected at many points. [ABSTRACT FROM AUTHOR]

Infection by varicella-zoster virus (VZV) can be prevented by using live attenuated vaccines. VZV vaccine strains are known to evolve rapidly in vivo, however, their genetic and biological effects are not known. In this study, the plaque-purified vaccine strain Suduvax (PPS) was used to understand the genetic changes that occur during the process of propagation in in vitro cell culture. Full genome sequences of three different passages (p4, p30, and p60) of PPS were determined and compared for genetic changes. Mutations were found at 59 positions. The number of genetically polymorphic sites (GPS) and the average of minor allele frequency (MAF) at GPSs were not significantly altered after passaging in cell culture up to p60. The number of variant nucleotide positions (VNPs), wherein GPS was found in at least one passage of PPS, was 149. Overall, MAF changed by less than 5% at 52 VNPs, increased by more than 5% at 42 VNPs, and decreased by more than 5% at 55 VNPs in p60, compared with that seen in p4. More complicated patterns of changes in MAF were observed when genetic polymorphism at 149 VNPs was analyzed among the three passages. However, MAF decreased and mixed genotypes became unequivocally fixed to vaccine type in 23 vaccine-specific positions in higher passages of PPS. Plaque-purified Suduvax appeared to adapt to better replication during in vitro cell culture. Further studies with other vaccine strains and in vivo studies will help to understand the evolution of the VZV vaccine. [ABSTRACT FROM AUTHOR]

The Gongsanseong Fortress in Gongju, Republic of Korea, is one of the most essential remains for historical research of Baekje Kingdom, and reinforces on the fortress wall has continuously been implemented since the sixth century to present. Through visual inspections of the fortress ramparts, sections in which structural deformations have occurred, and then they were classified by morphological characteristics based on lithofacies that compose the ramparts, shape of each rock, and construction method. Also, automatic sensors that can measure behavior changes of the ramparts, and the surrounding environment were installed to monitor microscale movements of the ramparts and changes in the surrounding microclimate. As a result, damages were shown intensively on the ramparts that retain specific morphological characteristics, and it has been discovered that, even for the ramparts located in an identical environment, morphological characteristics affect damages and structural deformations of the ramparts because of behavior changes for minutes. Such changes in behavior can be classified based on reversibility and predictability, and different management schemes must be applied based on behavior change patterns. If we continuously operate and develop this monitoring system, it is expected to be meaningfully utilized in efficient maintenance of the cultural heritage of the ramparts. [ABSTRACT FROM AUTHOR]

The stability of graphene dispersions in water is of both scientific and technological significance. We studied the dispersion stability of electrochemically exfoliated graphene in an aqueous medium to minimize the strong aggregation tendency, within a short period, of graphene prepared in various electrolytes. This study focused on increasing the dispersion stability of graphene and finding the reason for its poor dispersion stability. The residual electrolyte trapped in the graphene layers was difficult to be removed from electrochemically exfoliated graphite and caused a significant aggregation. The stability and dispersion concentration can be improved by removing the trace amount of aqueous electrolyte. The aggregation mechanism of graphene in aqueous media is proposed and discussed in detail. [ABSTRACT FROM AUTHOR]

Microglial activation is critical for obesityinduced hypothalamic inflammation and is closely associated with pathologies of metabolic complications. In this study, we investigated the effect of filbertone, a main aroma compound of hazelnuts, on microglia-mediated inflammatory responses in vitro and obesity-induced hypothalamic inflammation in vivo. BV2 microglial cells were stimulated with lipopolysaccharide (LPS) in the presence or absence of filbertone. Meanwhile, C57BL/6 mice were fed for 10- weeks on a high-fat diet (HFD) supplemented with 0.2% filbertone. Levels of inflammatory mediators in microglia or hypothalamus were measured using enzyme-linked immunosorbent assays or quantitative real-time PCR. Filbertone significantly inhibited nitrite oxide production, inducible nitric oxide synthase expression, and inflammatory cytokine production in LPS-stimulated microglia. Filbertone also inhibited LPS-stimulated activation of inflammatory signaling molecules, mitogen-activated protein kinases (MAPK) such as extracellular signal-regulated kinases and p38, and the degradation of inhibitory nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) in microglia. Moreover, filbertone supplementation markedly suppressed the expression of inflammatory cytokines and microglia activation marker in the hypothalamus of obese mice fed a HFD. These results suggest that filbertone reduces HFD-induced microglial activation through inhibition of the MAPK and NF-κB pathways, and thus protects obesityinduced hypothalamic inflammation. Filbertone may be useful for protection of microglia-mediated hypothalamic inflammation in obese condition and related metabolic complications. [ABSTRACT FROM AUTHOR]

Hypothalamic neurons including proopiomelanocortin (POMC)-producing neurons regulate body weights. The non-motile primary cilium is a critical sensory organelle on the cell surface. An association between ciliary defects and obesity has been suggested, but the underlying mechanisms are not fully understood. Here we show that inhibition of ciliogenesis in POMC-expressing developing hypothalamic neurons, by depleting ciliogenic genes IFT88 and KIF3A, leads to adulthood obesity in mice. In contrast, adult-onset ciliary dysgenesis in POMC neurons causes no significant change in adiposity. In developing POMC neurons, abnormal cilia formation disrupts axonal projections through impaired lysosomal protein degradation. Notably, maternal nutrition and postnatal leptin surge have a profound impact on ciliogenesis in the hypothalamus of neonatal mice; through these effects they critically modulate the organization of hypothalamic feeding circuits. Our findings reveal a mechanism of early life programming of adult adiposity, which is mediated by primary cilia in developing hypothalamic neurons. Ciliary defects and obesity has been associated, but the underlying mechanism is unclear. Here, the authors show that inhibition of ciliogenesis in POMC neurons during development results in lysosomal protein degradation-dependent axonal disruption and adult obesity in mice. [ABSTRACT FROM AUTHOR]

Mutations that inactivate negative translation regulators cause autism spectrum disorders (ASD), which predominantly affect males and exhibit social interaction and communication deficits and repetitive behaviors. However, the cells that cause ASD through elevated protein synthesis resulting from these mutations remain unknown. Here we employ conditional overexpression of translation initiation factor eIF4E to increase protein synthesis in specific brain cells. We show that exaggerated translation in microglia, but not neurons or astrocytes, leads to autism-like behaviors in male mice. Although microglial eIF4E overexpression elevates translation in both sexes, it only increases microglial density and size in males, accompanied by microglial shift from homeostatic to a functional state with enhanced phagocytic capacity but reduced motility and synapse engulfment. Consequently, cortical neurons in the mice have higher synapse density, neuroligins, and excitation-to-inhibition ratio compared to control mice. We propose that functional perturbation of male microglia is an important cause for sex-biased ASD. The main cell types involved in autism spectrum disorders through elevated protein synthesis are not well identified. Here, the authors show that overexpression of translation initiation factor eIF4E in microglia results in autism-like behaviour in male, but not female, mice. [ABSTRACT FROM AUTHOR]

Mitochondrial dysfunction is strongly associated with the oocyte quality and aging, wherein the aged oocytes are related to the actin cytoskeleton integrity; however, whether this integrity is associated with mitochondrial dysfunction in oocytes from aged mice remains unclear. In the present study, we investigated the relationship between mitochondrial dysfunction and actin cytoskeleton instability in oocytes from the aged mice. We performed comparable analysis of mitochondrial motility between young, 1.5 μM cytochalasin B (CB)-treated young oocytes, and aged oocytes by confocal live imaging. Moreover, we analyzed the relationships between mitochondrial motility and maturation ratios, including ATP production ratio of the young, CB-treated young, and aged oocytes. Actin cytoskeleton instability in the aged oocytes and CB-treated young oocytes led to a significant decrease in the mitochondrial motility and low ATP productive ratios compared to those in the young group. Our data suggest that the actin cytoskeleton instability is presumably the primary cause for the loss of mitochondrial function in the aged murine oocytes. [ABSTRACT FROM AUTHOR]

The Royal Tombs at Songsanri have played considerable roles in the study of Baekje history since the Royal Tomb of King Muryeong was excavated, in untouched condition, in 1971. However, the stability of the Royal Tombs at Songsanri has been threatened by constant exposure to the external environment and infiltration by rainwater. In this study, behavioral monitoring of the walls was conducted using tilt sensors to obtain very precise data about the deformation of the structurally vulnerable walls, evaluate their behavioral characteristics and the influence of environmental changes on these behaviors, and diagnose the structural stability of the ancient tombs. In tomb no. 5, with the exception of relatively rapid behavioral changes attributed to the stabilization process of the tilt sensors, the walls remained stable. However, abnormal changes were observed at several positions in the walls of tomb no. 6 and the Royal Tomb of King Muryeong. These changes were attributed to environmental changes. Furthermore, the abnormal changes in the walls were found to coincide with increases in the soil water content due to rainfall and artificial environmental changes caused by the investigations in the tombs. These findings are expected to be useful in creating policies and designing countermeasures to preserve these historically and culturally valuable tombs. [ABSTRACT FROM AUTHOR]

Primary infections with the varicella-zoster virus (VZV) result in varicella, while latent reactivation leads to herpes zoster. Both varicella and zoster can be prevented by live attenuated vaccines. There have been reports suggesting that both clinical VZV strains and those in vaccine preparations are genetically polymorphic, containing mixtures of both wild-type and vaccine-type sequences at certain vaccine-specific sites. In this study, the genetic polymorphism of the VZV genome was examined by analyzing the frequencies of minor alleles at each nucleotide position. Next-generation sequencing of the clinical VZV strain YC02 passaged in an in vitro cell culture was used to identify genetically polymorphic sites (GPS), where the minor allele frequency (MAF) exceeded 5%. The number of GPS increased by 7.3-fold at high passages (p100) when compared to low passages (p17), although the average MAF remained similar. GPS were found in 6 open reading frames (ORFs) in p17, 35, and 54 ORFs in p60 and p100, respectively. GPS were found more frequently in the dispensable gene group than the essential gene group, but the average MAF was greater in the essential gene group. The most common two major/minor base pairs were A/g and T/c. GPS were found in all three passages at 16 positions, all located in the reiterated (R) region. The population diversity as measured by Shannon entropy increased in p60 and p100. However, the entropy remained unchanged in the R regions. [ABSTRACT FROM AUTHOR]

Avian influenza viruses circulating in birds have caused outbreaks of infection in poultry and humans, thereby threatening public health. Recently, a highly pathogenic avian influenza (HPAI) virus (H5N8) of clade 2.3.4.4 emerged in Korea and other countries and caused multiple outbreaks in domestic and wild birds, with concerns for human infection. To combat HPAI viral infections, novel vaccines are likely to be the most effective approach. Therefore, in this study, we generated H5N8 vaccine candidate viruses based on a Korean isolate (A/broiler duck/Korea/Buan2/2014). The vaccine candidate viruses were 2:6 reassortants expressing the two surface glycoproteins of A/broiler duck/Korea/Buan2/2014 on an A/Puerto Rico/8/34 (PR8) backbone generated by using an eight-plasmid-based reverse genetics system with or without replacement of the multi-basic amino acid cleavage motif (MBCM, a crucial pathogenic factor in HPAI virus) with a bi-basic amino acid cleavage motif (BBCM) in their HA. An H5N8 vaccine candidate virus containing the BBCM showed attenuated pathogenesis in embryonated eggs and exhibited less virulence in the infected mice compared with the wild H5N8 virus containing an MBCM. Vaccination with an inactivated preparation of the vaccine candidate virus protected mice from lethal H5N8 viral challenge. This is the first report of the development and evaluation of H5N8 vaccine strains (with an MBCM or BBCM) of HA clade 2.3.4.4 as vaccine candidates. Our findings suggest that H5N8 strains with a BBCM instead of an MBCM might be considered for H5N8 vaccine seed virus development or as a reference vaccine against H5N8 viral strains. [ABSTRACT FROM AUTHOR]

Live attenuated vaccine strains have been developed for Varicella-Zoster virus (VZV). Compared to clinically isolated strains, the vaccine strains contain several non-synonymous mutations in open reading frames (ORFs) 0, 6, 31, 39, 55, 62, and 64. In particular, ORF62, encoding an immediate-early (IE) 62 protein that acts as a transactivator for viral gene expression, contains six non-synonymous mutations, but whether these mutations affect transactivation activity of IE62 is not understood. In this study, we investigated the role of non-synonymous vaccine-type mutations (M99T, S628G, R958G, V1197A, I1260V, and L1275S) of IE62 in Suduvax, a vaccine strain isolated in Korea, for transactivation activity. In reporter assays, Suduvax IE62 showed 2- to 4-fold lower transactivation activity toward ORF4, ORF28, ORF29, and ORF68 promoters than wild-type IE62. Introduction of individual M99T, S628G, R958G, or V1197A/I1260V/L1275S mutations into wild-type IE62 did not affect transactivation activity. However, the combination of M99T within the N-terminal Sp transcription factor binding region and V1197A/I1260V/L1275S within the C-terminal serine-enriched acidic domain (SEAD) significantly reduced the transactivation activity of IE62. The M99T/V1197A/I1260V/L1275S mutant IE62 did not show considerable alterations in intracellular distribution and Sp3 binding compared to wild-type IE62, suggesting that other alteration(s) may be responsible for the reduced transactivation activity. Collectively, our results suggest that acquisition of mutations in both Met 99 and the SEAD of IE62 is responsible for the reduced transactivation activity found in IE62 of the VZV vaccine strains and contributes to attenuation of the virus. [ABSTRACT FROM AUTHOR]

A new and precise 6-Degree-of-freedom (DoF) Fiber Bragg grating (FBG) force-moment sensor integrated with a platform frame was proposed for the haptic feedback of loadings at the tip cutting tools of end-effectors of a minimally invasive surgical robot. As the platform deformed during surgery, the attached FBG pretensioned with 2000 μm strain. Strains were calculated by Finite element analyses (FEAs) and related to optical wavelength equations. Experiments integrated with sagacious ways of how to apply forces and moments for the sensor fabricated were conducted to measure the strains and wavelength changes caused in FBGs. Experimental wavelength changes correlated well in 3% to 4% error with the FEA results for all cases. A realistic design of a small 6-DoF FBG force-moment sensor was proposed using the analytic method. Wavelength changes slightly increased as temperature increased in the study of thermal compensation. [ABSTRACT FROM AUTHOR]

In this technique development study, high-resolution peripheral quantitative computed tomography (HR-pQCT) was applied to non-invasively image and quantify 3D joint space morphology of the wrist and metacarpophalangeal (MCP) joints of patients with rheumatoid arthritis (RA). HR-pQCT imaging (82  μm voxel-size) of the dominant hand was performed in patients with diagnosed rheumatoid arthritis (RA, N = 16, age: 52.6 ± 12.8) and healthy controls (CTRL, N = 7, age: 50.1 ± 15.0). An automated computer algorithm was developed to segment wrist and MCP joint spaces. The 3D distance transformation method was applied to spatially map joint space width, and summarized by the mean joint space width (JSW), minimal and maximal JSW (JSW.MIN, JSW.MAX), asymmetry (JSW.AS), and distribution (JSW.SD)—a measure of joint space heterogeneity. In vivo precision was determined for each measure by calculating the smallest detectable difference (SDD) and root mean square coefficient of variation (RMSCV%) of repeat scans. Qualitatively, HR-pQCT images and pseudo-color JSW maps showed global joint space narrowing, as well as regional and focal abnormalities in RA patients. In patients with radiographic JSN at an MCP, JSW.SD was two-fold greater vs. CTRL ( p < 0.01), and JSW.MIN was more than two-fold lower ( p < 0.001). Similarly, JSW.SD was significantly greater in the wrist of RA patients vs. CTRL ( p < 0.05). In vivo precision was highest for JSW (SDD: 100  μm, RMSCV: 2.1%) while the SDD for JSW.MIN and JSW.SD were 370 and 110  μm, respectively. This study suggests that in vivo quantification of 3D joint space morphology from HR-pQCT, could improve early detection of joint damage in rheumatological diseases. [ABSTRACT FROM AUTHOR]

Molecular phylogenetic studies of the HIV-1 isolated from Koreans have suggested the presence of the so-called “Korean clade”, which can be defined as a cluster free of foreign isolates. The Korean clade accounts for more than 60% of Korean isolates and exerts characteristic amino acid sequences. Thus, it is merited to estimate when this Korean clade first emerged in order to understand the evolutionary pattern of the Korean clade. We analyzed and reconstructed the most recent common ancestor (MRCA) sequences from nef (n=229) and vif (n=179) Korean clade sequences. Linear regression analyses of sequence divergence estimates were plotted against sampling years to infer the year in which there was zero divergence from the MRCA sequences. MRCA sequences suggested the Korean clade was first emerged around 1984, before the first detection of HIV-1 in Korea in 1985. Further studies on synonymous and nonsynonymous substitution rates suggested positive selection event for the Korean clade, while other subtype B had undergone negative to neutral evolution. [ABSTRACT FROM AUTHOR]

Phylogenetic studies of the HIV-1 gene sequences isolated from Korean patients have suggested that most of Korean isolates belong to the subtype B strain. This study aims to characterize the Korean clade by molecular phylogenetic analysis using all of the Korean nef gene sequences registered in the NCBI GenBank (N=422), in addition to 41 reference strains and 94 foreign isolates. Through phylogenetic analyses, we verified that most of the Korean isolates belonged to the subtype B, where 78.8 % are clustered exclusively of foreign isolates. This cluster has been named the Korean clade subtype B (KcB) in order to distinguish it from other subtype B clusters. Genetic distance analysis suggested that the KcB cluster was more homogeneous and clearly distinctive from the non-Korean clade subtype B (NKcB). Comparison of consensus amino acid sequences from KcB and NKcB revealed that characteristic KcB signature amino acid patterns composed of 11 amino acid residues, whose frequencies in the KcB were significantly higher than in the NKcB. The KcB signature amino acid residues were critical in identifying KcB from NKcB, since substitution of the NKcB sequences with KcB signature amino acids relocated them to the Koran clade, and vice versa. [ABSTRACT FROM AUTHOR]

This study evaluates the pollution load on a creek based on the physicochemical and mineralogical properties of old tailings. The Sanggok mine is one of the largest lead-zinc producers in the Hwanggangri mining district, Republic of Korea. The vertical profile of the old tailings in the mine area can be divided into three units based on color change, and mineralogical and textural variations, as well as physical and chemical properties. Unit I (surface accumulation and oxidized heterogeneous tailing soil) has lower pH and higher Eh than unit II (originally unoxidized dumped tailing soil) and unit III (pebble-bearing bottom soil). The conductivity data indicates that unit I and II have very high values compared to unit III and basement. The mine area consists mainly of carbonate rocks; however, mineral constituents of tailing soil and sediments near the mine were mainly composed of quartz, mica, feldspar, amphibole, calcite, dolomite, magnesite, and clay minerals. Units I and II are characterized by high abundances of siderite, locally pyrite, and dolomite. Precipitates in the mining drainage mainly included: smectite, illite, berthierine, quartz, siderite, hexahydrite, and Ca-ferrate. Among the separated metallic minerals, tailing soils and sediments of highly concentrated toxic metals are found: some pyrite, arsenopyrite, chalcopyrite, sphalerite, galena, malachite, goethite, various hydroxide, and uncertain secondary minerals. Units I and II are characterized by relatively high concentrations of Ca, Fe, Mn and low contents of Al, Mg, K, Na, Ti, rare earth elements (REEs) that correlated with the proportion of secondary minerals. Potentially toxic elements such as Ag, As, Cd, Cu, Pb, Sb, and Zn are highly enriched in the upper two units. This metal concentration can be influenced by changes in the depth because of oxic and suboxic zonal distribution. The removal zone (unit I) has probably migrated below the elevation of the maximum enrichment layer due to deepening of the oxic/suboxic boundary. In most of the materials, the enrichment index is higher than 3.62. The highest value of 42.55 is found in the oxidation surface soils of the tailing pile. An average enrichment index of the profiles and precipitates are 27.62 and 22.62, respectively. Rocky basement soils have an average enrichment index of 6.63, which is influenced by overlying the tailing pile. The water quality and habitat of the Sanggok creek are severely polluted. Polluted surface water may also negatively impact the agricultural soil and groundwater. [ABSTRACT FROM AUTHOR]

Environmental pollution in the Kongjujeil mine creek was determined on the basis of physicochemical and mineralogical properties for various kinds of waters, soils, precipitates and sediments collected in August and December 1998. The hydrochemistry of water is characterized by an enrichment in concentrations of Ca2+, Si, alkali ions, NO3 − and Cl- in ground and surface water, where relatively the mine waters are significantly enriched in Ca2++Mg2+, Al, heavy metals and SO4 2− concentrations. The mine waters have lower pH (3.24) and higher EC (613 μS/cm) compared with those of ground and surface water. The ranges of δD and δ18O values (SMOW) in the water are −50.2 to −61.6‰ and −7.0 to −8.6‰. Using a computer code, the saturation indices of albite, calcite and dolomite in the mine water show that it is undersaturated, and has progressively evolved toward the equilibrium state. Ground and surface water are nearly saturated. The gibbsite, kaolinite and smectite are supersaturated in the surface and groundwater. Geochemical modeling shows that mostly toxic metals exist largely in the form of metal sulfates and free metals in mine water. These metals in the surrounding fresh water could be formed of carbonate or hydroxide complex ions. Minerals within the soil and sediment near the mining area were partly variable consisting of quartz, mica, alkali feldspar, plagioclase, chlorite, vermiculite, berthierine and clay minerals. The separated heavy minerals, soil and sediment are composed of some pyrite, arsenopyrite, chalcopyrite, sphalerite, galena, malachite, goethite and various hydroxide minerals. Some potentially toxic elements (As, Cd, Cu, Pb, Sb and Zn) are found in extremely high concentrations in the surface soils in the vicinity of the mine. The enrichment index of heavy metals in sediment and surface soil of the mine drainage was very severe, while it was not so great in the cultivated soil. [ABSTRACT FROM AUTHOR]

FDDI networks have been widely deployed to support real-time traffic such as voice and video communications. However FDDI's medium access control (MAC) protocol can transmit synchronous messages up to at most one half of the total bandwidth of the FDDI network. In a recent paper by K. Shin and Q. Zheng [Shin95], a modification to the FDDI MAC protocol, called FDDI-M, has been proposed to double a ring's ability to support synchronous traffic. In this paper we present an analytical study of the timing properties of the FDDI-M protocol. Using the Worst Case Achievable Utilization (WCAU) as the performance metric, we first evaluate the performance of various synchronous bandwidth allocation (SBA) schemes in guaranteeing synchronous message deadlines. It is found that, in comparison with FDDI, the FDDI-M protocol results in a higher WCAU for the normalized proportional SBA scheme. However, for the local SBA schemes, the WCAU values remain zero. Next, other performance metrics such as throughput and percentage of frames missing deadlines are examined using simulation. A series of simulations using actual MEPG video traffic confirms that FDDI-M does provide superior synchronous transmission characteristics. [ABSTRACT FROM AUTHOR]

This study identifies the technique applied for building the rammed earth wall of the 13th Korean fortress, Ganghwa Jungseong, by analyzing its physical, mineralogical, granulometric, and geochemical characteristics. Furthermore, mutual homogeneities between the rammed earth wall and host rock, top soil, and sub-surface soil collected around the fortress were interpreted. The ground of the rammed earth wall was not created artificially but made via soil preparations containing loamy soils from weathered bedrock. The foundation part was built using various layers of soils having different colors, magnetic susceptibilities, particle sizes, and organic components. In particular, a layer of loamy saprolite was generated to enhance the stability of the foundation and improve ventilation and draining throughout the structure. The body of the wall is composed of silty loam at the bottom and silty loam to loam from the middle to the top. Techniques that alternately harden soils using different particle sizes enable external shock absorption and prevent crack formation owing to temperature changes during winter and summer. The rammed earth wall and the soils around the fortress contained related rock-forming materials had similar magnetic susceptibilities and geochemical characteristics, which indicated that they have a genetically common source. Moreover, the rammed earth wall was built using the soil weathered from the banded gneiss because it was correlated to the banded gneiss constituting the bedrock around the fortress. [ABSTRACT FROM AUTHOR]