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Lithology is an important control on the efficiency of bedrock incision and thus the pace of landscape evolution. Rock strength is commonly considered the limiting lithologic factor that resists erosion. Yet, rock strength is a dynamic property that oscillates during advection of rock to the channel surface as damaging processes weaken rock and erosion exposes fresh rock. We approach the problem by investigating damage on bedrock surfaces that vary by the frequency they are eroded in channels of different lithologies. Our data set includes measurements of channel slope and width to characterize channel morphology, and Schmidt hammer rebound, P wave velocity, slake durability, and porosity to characterize the mechanical properties of channel surfaces. The average damage accumulation rate of lithologies ranges over 41% of the mean. We find a range of damage patterns among the different lithologies. Local surface damage increases with erosion frequency in channels comprised of coarse‐grained bedrock but decreases with erosion frequency in channels comprised of fine‐grained bedrock. We interpret these patterns to develop from lithological influences on weathering, abrasion, and the threshold of damage to erosion. The cross‐channel damage patterns between channel floors and margins are well correlated with stream power demonstrating links between microstructural rock properties, reach‐scale morphology, and landscape‐scale processes. We conclude that the morphodynamics of bedrock channels are sensitive to the lithological influences on the direction and magnitude of feedback in the coevolution of bedform morphology and the mechanical properties of the surface. Plain Language Summary: Rivers shape the landscape by carving out valleys into rock. Some types of rock are harder to carve than other types of rock, but it is not clearly understood why because there are many physical and chemical weathering processes that attack rock other than the river. Using several dry river channels, we take many measurements of rock strength along the bedrock surface that forms the river channels. We take advantage of the different channel surfaces that are either shielded or exposed to the downstream flow of river sediment to get a sense of how the bedrock is damaged by sediment impacts and by weathering. We find that the size and type of minerals that make up the bedrock influence the pattern of rock damage that develops through complex feedbacks that occur as bedrock material is either weakened or eroded thereby exposing fresher material that lies underneath. These damage patterns in turn control the shape of the channel, and therefore, the erosive potential of the flowing water. Our findings demonstrate how microscale rock properties can influence the shaping of landscapes. Key Points: Erosion frequency and surface damage modulate the spatial variability in mechanical properties of bedrock channelsGrain size and mineralogy control damage by weathering and abrasion, which influence the slope, width, and roughness of bedrock channelsThe relation between rock damage and rock‐erodibility is unique for different lithologies [ABSTRACT FROM AUTHOR]

Background and purpose: Few studies have assessed the role of vitamin D in the association between cardiovascular risk factors and cognitive function. Here, the aim was to investigate the association between cardiovascular health (CVH) and cognitive function according to vitamin D level in a middle‐aged Korean population. Methods: This cross‐sectional study included 840 men and 1811 women (mean age 57.2 years) from the Cardiovascular and Metabolic Diseases Etiology Research Center study baseline enrolment (2013–2018). Life's Simple 7 tools from the American Heart Association were used to assess CVH. Cognitive function was evaluated using the Mini‐Mental State Estimation for Dementia Screening (MMSE‐DS), and the serum 25‐hydroxyvitamin D level was measured. Results: In the adjusted generalized linear regression models, no significant association between a high Life's Simple 7 score (4–7 metric at optimal level) and MMSE‐DS score (β = 0.01, P = 0.93) was found. Amongst men with a high vitamin D level, the high Life's Simple 7 score group showed a significantly higher MMSE‐DS score (β = 0.48, P = 0.03). However, amongst men in the low vitamin D group, the association was opposite with no statistical significance (β = −0.23, P = 0.08). In women, the results were similar, but both strata according to vitamin D level showed no statistical significance. Conclusions: Our findings suggest that vitamin D is an effect modifier in the association between CVH and cognition, especially in men. [ABSTRACT FROM AUTHOR]

Background Non-invasive body sculpting procedures are becoming increasingly popular. High-intensity focused ultrasound ( HIFU) treatment is a non-surgical fat reduction procedure that permanently destroys unwanted abdominal fat. Despite its increasing popularity, evaluation methods for the procedure have not yet been fully developed. Aims The objective of this study was to develop evaluation methods for HIFU for non-surgical, permanent fat reduction in the anterior abdomen using a porcine model. Methods The abdomens of female pigs ( Sus scrofa, n = 7) were treated with a HIFU device ( SCIZER™, Classys Inc, Seoul, Korea). We examined treatment effects using photography, ultrasound, gross and microscopic pathology, and serum lipid and liver function level analysis, carbon tracer test, and histological examination in order to determine the mechanism of action, efficacy, and safety of the procedure. Results HIFU treatment effectively reduced abdominal fat in a porcine model; it accurately treated the target subcutaneous fat layer and the subcutaneous fat was reduced effectively via ultrasonic measurement after HIFU treatment. On histological staining (H&E, toluidine blue, oil red O and immunohistochemistry), we found that subcutaneous fat reduction occurred effectively via accurate treatment of the targeted subcutaneous fat layer. On hematological assay, there were changes within normal range, and values remained stable after 48 h. Via carbon tracer test, the migration of activated macrophages was identified within the axillary lymph node ( LN). PPAR-delta, a protein defined by immunohistochemistry staining, was overexpressed in the early stage on days 1 and 7, but a gradual decreasing pattern was confirmed. Conclusion We successfully used a HIFU device for body contouring and fat reduction in a pre-clinical study. These results provide that the essential clues toward the effective evaluation, guiding selection of the appropriate diagnostic investigations. [ABSTRACT FROM AUTHOR]

The efficacy of amoxicillin sodium for controlling field and experimental Streptococcus iniae and S. parauberis infections in olive flounder ( Paralichthys olivaceus) was evaluated after a single intramuscular administration. Furthermore, the minimal inhibitory concentrations ( MIC) against 21 Streptococcus strains were determined. In addition, the pharmacokinetics and residue depletion in olive flounder were investigated. Single intramuscular doses of amoxicillin sodium at 20, 40, 80, and 160 mg/kg b.w. fish significantly reduced cumulative mortality rates to 18.8-31.3% ( P < 0.05) for S. iniae and to 5.0-15.0% ( P < 0.01) for S. parauberis, whereas the S. iniae- and S. parauberis-infected positive control groups showed cumulative mortality rates of 68.8% and 60.0%, respectively. In a S. parauberis outbreak, amoxicillin sodium reduced the cumulative mortality rate to 7.5% and 4.8% at 20 and 40 mg/kg b.w. fish, respectively, whereas that of the untreated control group was 35.2%. Peak plasma concentrations ( Cmax) following a single intramuscular dose of 40 and 80 mg/kg b.w. fish were 62.64 ( Tmax, 1.59 h) and 87.61 ( Tmax, 3.02 h) μg/ mL, respectively, with large AUC0−t/ MIC and Cmax/ MIC ratios, and sufficient T > MIC (time for maintaining plasma drug concentration greater than MICs) for S. iniae and S. parauberis. The estimated withdrawal period of amoxicillin sodium from muscle of olive flounder was about 8 days at 40 mg/kg b.w. fish (at 22 ± 1 °C). These results demonstrated a single intramuscular administration of amoxicillin sodium to be effective against streptococcosis in olive flounder. [ABSTRACT FROM AUTHOR]

The genus Megalocytivirus is known to infect a wide range of cultured marine fish. In this study, we examined the pathogenicity of FLIV ( Megalocytivirus from olive flounder, genotype III) and RBIV ( Megalocytivirus from rock bream, genotype I) to their homologous and heterologous host species. Olive flounder (7.5 ± 1.3 cm) injected with FLIV [major capsid protein ( MCP) gene copies, 6.8 × 103-6.5 × 106/fish] at 24 °C did not die until 90 days post-infection (dpi). The average virus replication in the spleen peaked (1.27 × 106/fish) at 20 dpi. Rock bream (6.5 ± 1.5 cm) injected with FLIV (8.8 × 105 and 6.5 × 106/fish of MCP copies) showed no mortality until 50 dpi. The rock bream that survived after FLIV infection were rechallenged with RBIV at 50 dpi had 100% mortality, showing that there is no cross-protection between FLIV and RBIV. Temperature shifting (26 °C and 20 °C at 12 h intervals) did not cause FLIV-specific mortality into olive flounder, but higher virus copies were observed in the fish exposed to higher stocking density. This study demonstrates that FLIV and RBIV have different antigenic and pathogenic characteristics and that FLIV has low pathogenicity to olive flounder. [ABSTRACT FROM AUTHOR]

The main objective of this study was to investigate the effects of hot mix asphalt material properties on the performance of flexible pavements via mechanistic approach. 3D Move Analysis software was utilized to determine rutting and cracking distresses in an asphalt concrete (AC) layer. Fourteen different Superpave mixes were evaluated by utilizing results of the Dynamic Modulus (|E⁎|) Test and the Dynamic Shear Modulus (|G⁎|) Test. Results showed that with the increase of binder content, the tendency of rutting in AC layer increased. However, with the increase of binder content, the cracking of AC layer lessened. Furthermore, when different binder grades were evaluated, results showed that with the increase of the upper binder grade number, rutting decreased, and with the increase of the lower binder grade number, rutting increased. Furthermore, analysis showed that with the increase of the lower binder grade number, higher percent of bottom up cracks would result. As a result of the analysis, binder grade should not be solely considered for cracking in AC layer; binder content and aggregate structure play a big role. Finally, results illustrated that the mechanistic approach is a better tool to determine the performance of asphalt pavement than commonly used methods. [ABSTRACT FROM AUTHOR]

Rock bream iridovirus ( RBIV) causes huge losses, especially in rock bream Oplegnathus fasciatus. Rock bream injected with RBIV and held at 29, 26, 23 or 20 °C had 100% mortality. Conversely, all infected fish held at 17 °C survived even after the temperature was progressively increased to 26 °C at 100 dpi. Rock bream exposed to virus and held for 2, 4 and 7 days at 23/26 °C before the temperature was reduced to 17 °C had mortality rates of 26.6/73.2%, 66.6/100% and 93.4/100%, respectively, through 100 dpi. When surviving fish had the water temperature increased from 17 to 26 °C at 100 dpi, they did not exhibit signs of disease and had low virus copy numbers (below 103). To investigate the development of a protective immune, rock bream were infected with RBIV and held at 23 °C before shifting the water temperature to 17 °C at 4 dpi. All injected fish survived until 120 dpi. While 100% of the previously unexposed fish died, 80.2% of the previously infected fish survived. When the survivors were rechallenged again at 160 dpi, no further mortality occurred. The high survival rate of fish following rechallenge with RBIV indicates that protective immunity was established in the surviving rock bream. [ABSTRACT FROM AUTHOR]

Background/aims Cryolipolysis is a noninvasive method for the selective reduction of localized fat tissues. It has demonstrated efficacy in both clinical and preclinical trials; however, despite its popularity, its mechanisms of action and evaluation methods are not yet fully defined. The purpose of this study was to improved methods for cryolipolysis using a porcine model. Methods The abdomens of female PWG micro-pigs were treated with a cooling device ( CRYOLIPO II™), and we examined the treatment effects using photography, three-dimensional photography, ultrasound, gross, and microscopic pathology, and serum lipid level analyses in order to determine the mechanism of action, efficacy, and safety of CRYOLIPO II™. Results CRYOLIPO II™ successfully reduced abdominal fat in our porcine model. Gross and microscopic histological results confirmed the noninvasive cold-induced selective subcutaneous fat destruction, and showed increases in pre-adipocyte differentiation and in the activation of lipid catabolism. In particular, we found that CRYOLIPO II™ may increase PPARδ (delta) levels in adipose tissue at 30-60 days post-treatment. Conclusion Fat reduction by cryolipolysis was successfully achieved in our porcine model. Thus, our findings indicate that CRYOLIPO II™ may be a promising fat reduction device for body contouring and fat reduction in humans, and that cryolipolysis exerts its effects, at least partly, by targeting the PPARδ signaling pathway. These results show that both investigative and diagnostic potentials capacity. [ABSTRACT FROM AUTHOR]

The article reports on a study on detecting streptococcus iniae by using the loop-mediated isothermal amplification (LAMP). The coccus affects the freshwater and marine fish species and causes substantial damages to the aquaculture industry. According to the study, the phosphoglucomutase based LAMP could be a suitable routine diagnostic tool for the preliminary screening and surveillance of the coccus and for the detection of early infection and carrier fishes.

Cultured black rockfish, Sebastes schlegeli, suffered mass mortalities during winter 2008 and spring 2009 in Korea, showing clinical signs of ulcer lesions and haemorrhages over their body surface. The aetiological agent was identified as Aeromonas salmonicida (strains RFAS-1, -2 and -3), which is a non-pigmented, slow-growing bacterium. Phenotypes of RFAS strains showed variation, while 16S rRNA, gyrB, rpoD, dnaJ and recA gene sequences of all the strains were affiliated to A. salmonicida. In particular, vapA gene sequences of the strains were most closely related to one of the five subspecies of A. salmonicida subsp. masoucida (=KCCM 40239). LD values of RFAS-1 for intraperitoneal and intramuscular injection were 1.5 × 10 and 1.5 × 10 cfu/rockfish, respectively. However, A. salmonicida strains KCCM 40239 and SAS-1, which originate from masou and chum salmon, respectively, were not pathogenic to black rockfish. RFAS strains, possessing A-layer protein on their surface, exhibited β-haemolytic activity against rockfish erythrocytes and capability to survive in rockfish serum, which seem to be associated with virulence. [ABSTRACT FROM AUTHOR]

‘Soft tunic syndrome’ causes mass mortality in the edible ascidian Halocynthia roretzi in Korean and Japanese aquaculture. In histopathological comparison, there were no specific differences between diseased specimens from Korea and Japan, indicating that soft tunic syndrome occurring in Korea and Japan is the same disease. No bacterial or protozoan cells were microscopically detected in either healthy or diseased tunics suggesting they are not the direct causes of soft tunic syndrome. Attempts were made to isolate virus from affected ascidians taking into account temperature conditions in which soft tunic syndrome is most prevalent in the field. However, no viruses were isolated from diseased or non-diseased specimens using chinook salmon embryo (CHSE-214), flounder fin (FFN) or epithelioma papillosum cyprini (EPC) cell lines. [ABSTRACT FROM AUTHOR]

In Japan and Korea, outbreaks of scuticociliatosis have frequently occurred in Japanese flounder, Paralichthys olivaceus. Morphological observations and small subunit rRNA gene sequences have shown that the causative agent of scuticociliatosis in the flounder is Miamiensis avidus (syn. Philasterides dicentrarchi). In this study, we elucidated the antigenic differences between six Japanese M. avidus isolates as an initial step toward developing an effective vaccine against the disease. Four Japanese flounder isolates (IyoI, Nakajima, JF05To and Mie0301 isolates), one spotted knifejaw, Oplegnathus punctatus, isolate (SK05Kyo), and one ridged-eye flounder, Pleuronichthys cornutus, isolate (RF05To) were subjected to serological analysis. Antisera against IyoI, SK05Kyo, Nakajima and Mie0301 isolates were raised in rabbits and used for immobilization assays and Western blotting. Immobilization assays showed that the six isolates could be divided into three groups, tentatively designated serotype I for IyoI, JF05To, RF05To, SK05Kyo, serotype II for Nakajima and serotype III for Mie0301. Western blotting results supported these three serotypes, with marked similarities in the banding profiles of IyoI, JF05To, RF05To and SK05Kyo isolates, which were distinct from the Nakajima and Mie0301 isolates. Three isolates, IyoI, Nakajima and Mie0301 that were selected as representatives of each serotype, were highly pathogenic to Japanese flounder by experimental infection. Based on these findings, we propose that there are at least three M. avidus serotypes in Japan. [ABSTRACT FROM AUTHOR]

Olive flounder artificially infected with lymphocystis disease virus (LCDV) were reared at 10, 20 and 30 °C for 60 days, to compare LCD-incidence. In the fish reared at 20 °C, lymphocystis cells appeared on the skin and fins at 35 days post-challenge, and the cumulative LCD-incidence was 80% at 60 days. High levels of LCDV, with a mean polymerase chain reaction (PCR) titre of 106 PCR-U mg−1 tissue, were detected in the fins and skin of LCD-affected fish at 20 °C, but were not detected in the spleen, kidney, brain and intestinal tissues of these fish. No LCD clinical signs were observed in the fish reared at 10 °C and 30 °C; however, a low level of LCDV (103 PCR-U mg−1 tissue) was detected in the fins and skin of these fish. By increasing the rearing temperature from 10 to 20 °C, lymphocystis clusters appeared on the skin and fins of the fish with no previous LCD clinical signs within 33 days after the temperature change. It was shown that permissive cells for LCDV infection exist in the epidermis of olive flounder. At low temperatures, small amounts of LCDV were able to persist over a period extended for a further 45 days in the fish epidermis, even though the fish showed no LCD clinical signs. The optimum growth temperature of LCDV is near 20 °C. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented which discusses the result of a phylogenetic analysis of lymphocystis disease virus from tropical ornamental fish species based on a major capsid protein gene.

Turbot iridovirus (TBIV), a member of the genus Megalocytivirus in the family Iridoviridae, was isolated from diseased turbot, Psetta maximus (L.), in Korea in 2003. In this study, experimental infection of turbot, Japanese flounder, Paralichthys olivaceus (Temminck & Schlegel), and rock bream, Oplegnathus fasciatus (Temminck & Schlegel), with TBIV was performed to evaluate the viral susceptibility of these fish species. After virus exposure, the mortalities of turbot reared at 22 and 25 °C were 60% and 100%, respectively, suggesting that TBIV is the causative agent of the mass mortality of turbot that occurred in Korea in 2003. Moreover, TBIV was detected in Japanese flounder and rock bream by polymerase chain reaction after experimental infection (26 days post-inoculation) despite no viral pathogenicity in these fish, suggesting that these two fish species are also susceptible to the virus. It is possible that horizontal transmission of TBIV occurs among these three fish species because turbot is routinely cultured with Japanese flounder and rock bream in Korea. [ABSTRACT FROM AUTHOR]

Studies were conducted by injecting/feeding white spot syndrome virus (WSSV) derived from infected shrimp, Penaeus monodon (Fabricius), to different life-stages, namely post-larvae, juveniles, sub-adults and adults of Macrobrachium rosenbergii (de Man). The disease was also induced in brood stock, and the eggs and larvae derived from these animals were subsequently tested for WSSV infection. All the stages except egg used for the experiment were found WSSV positive in histopathology, cross infection bioassay and polymerase chain reaction (PCR) analysis. Experimentally infected post-larvae and juveniles showed a high percentage of mortality and an increased rate of cannibalism. The cumulative mortality in post-larvae was up to 28%; with 28–40% cannibalism resulting in a maximum loss of up to 68%. In juveniles, observed mortality and cannibalism were 10–20% and 6.7–30.0%, respectively, and the maximum loss recorded was 50%. In sub-adults, mortality ranged from 2.8 to 6.7%, cannibalism was up to 20% and the total loss was up to 26.7%. Sub-adults and adults were found to be more tolerant to the infection as evidenced by the mortality pattern. A nested (two-step) PCR resulted in a 570-bp product specific to WSSV in all stages, except the eggs. [ABSTRACT FROM AUTHOR]

Presents polymerase chain reaction amplification and sequence analysis of irido-like virus infecting fish in South, Korea. Report of large-scale mortality among cultured fishes; Revelation of two groups of virus; Presence of slight variation in the DNA sequences among virus strains.

Analyzes the association of iridovirus-like infection with high mortalities of striped beakperch in southern coastal areas of the Korean peninsula. Histopathological evaluations and immunohistochemical staining; Infiltration of inflammatory cells into the blood vessel; Characteristics of the disease.

In the spring of 1992 and 1993, an epizootic with severe mortality occurred among cultured goldfish. Carassius auratus (L.), in Aichi and Nara Prefectures in Japan. A herpesvirus was isolated from moribund goldfish that induced cytopathic effects in FHM and EPC cells. The isolate was sensitive to IUdR (5-iodo-2-deoxyuridine), acid (pH 3) and ether. Transmission studies confirmed the pathogenicity of the viral isolate for goldfish while it was not pathogenic for fancy carp, Cyprinus carpio L. Diseased fish had no visible external signs except for listlessness, but internally there was softening and discolouration of the spleen and kidney, and necrotic foci in the haematopoietic tissue, splenic pulp, pancreas, and lamina propria and submucosa of the intestine. Electron microscopy revealed enveloped virions ranging from 170 to 220nm in diameter with hexagonal nucleocapsids (115-117 nm edge-to-edge diameter). The disease has been designated as herpesviral haematopoietic necrosis (HVHN), and to date, is the only herpesvirus infection to be described in goldfish. [ABSTRACT FROM AUTHOR]

Iridovirus infection causes serious economic damage in marine cultured fish in Japan, Hong Kong and Singapore, and the incidence of this disease has been increasing. Iridovirus of sea bass from offshore Hong Kong was isolated to determine the genetic similarities of the causative agents. The genomic DNA of iridovirus was purified and cloned. Four DNA clones were randomly chosen and sequenced to generate primers for the polymerase chain reaction (PCR). Corresponding DNA fragments of iridoviruses from sea bass from offshore Hong Kong, red sea bream in Japan and grouper in Thailand were detected. The analogous PCR products from geographically diverse iridoviruses may indicate a widespread distribution of an iridovirus of a single origin. [ABSTRACT FROM AUTHOR]

The article presents an abstract of the study "Dehydroevodiamine HCl Prevents the Impairment of Cognitive Function and the Neuronal Loss in Rat Model of Cognitive Disturbance." The study will be presented at a joint meeting of the International Society for Neurochemistry and the European Society for Neurochemistry which will be organized in Berlin, Germany, from August 8-14, 1999.