It has been reported that the antimicrobial susceptibility patterns of viridans streptococci vary according to geographical region. Although several studies on the antibiotic resistance of viridans streptococci in foreign countries have been reported, little is known about the distribution of resistance among viridans streptococci in Korea. In this study, 88 isolates of viridans streptococci from Korean students' dental plaque were identified as 12 different species. The susceptibility of these isolates to 8 antibiotics was investigated. The in vitro antibiotic activity of penicillin G, ampicillin, vancomycin, streptomycin, gentamicin, erythromycin, amoxicillin, and tetracycline was measured by the broth microdilution method. The range of the minimum inhibitory concentrations (MIC), MIC50, MIC90, and the percentage of the susceptible isolates were determined. Streptococcus mutans and Streptococcus salivarius were susceptible to the 8 antibiotics. Isolates with resistance to vancomycin, streptomycin, and amoxicillin were not found. The overall resistance rates of the 88 isolates to penicillin G, ampicillin, gentamicin, erythromycin, and tetracycline were 12.5%, 62.5%, 62.5%, 26.1%, and 26.1%, respectively.
Recently, Choe & Cheng (2002) have demonstrated that multiple magnetic flux systems with closed configurations can have more magnetic energy than the corresponding open magnetic fields. In relation to this issue, we have addressed two questions: (1) how much fraction of eruptive solar active regions shows multiple flux system features, and (2) what winding angle could be an eruption threshold. For this investigation, we have taken a sample of 105 front-side halo CMEs, which occurred from 1996 to 2001, and whose source regions were located near the disk center, for which magnetic polarities in SOHO/MDI magnetograms are clearly discernible. Examining their soft X-ray images taken by Yohkoh SXT in pre-eruption stages, we have classified these events into two groups: multiple flux system events and single flux system events. It is found that 74% (78/105) of the sample events show multiple flux system features. Comparing the field configuration of an active region with a numerical model, we have also found that the winding angle of the eruptive flux system is slightly above 1.5π.
The purpose of this study was to establish the reliability of the Trunk Impairment Scale (TIS) translated into Korea in patients with stroke. It also aims to score the quality of trunk movement and to be a tool for the treatment. The TIS consists of three subscales that static sitting balance, dynamic sitting balance and co-ordination. The TIS score ranges from a minimum of 0 to a maximum of 23. Twenty-five stroke patients (13 males, 12 females) were examined by two physiotherapists. Interrater and test-retest reliability were assessed. Kappa and weighted kappa values for the items of the trunk assessment of the TIS ranged from .67 to 1.00. Intraclass correlation coefficients for interrater and test-retest agreement were .95 and .97. Cronbach alpha coefficients for internal consistency range from .87 to .97. The TIS provide reliable assessments for the trunk and are valid scales for measuring trunk performance in patients with stroke. TIS can be used as a guideline for treatment and the assessment of quality of trunk activity.
Cross-legged sitting postures are commonly assumed during computer work. The purpose of this study was to determine the effects of leg crossing on trunk muscle activity while typing at a computer. Trunk muscle activity was measured in three 8 different sitting postures, in random order. These posture were: normal sitting with a straight trunk and both feet on the floor (NS), upper leg crossing (ULC), and ankle on knee (AOK). The right leg was crossed onto the left leg in both cross-legged postures. Twenty able-bodied male volunteers participated in this study. Subjects typed on a computer keyboard for one minute. Surface electromyography (EMG) was used to record bilateral muscle activity in the external oblique (EO). internal oblique (IO), and rectus abdominis (RA). The EMG activity of each muscle in the NS posture was used as a reference (100% EMG activity) in relation to the two cross-legged postures. Muscle activity in the right EO. right IO, and left IO was significantly lower in the ULC posture than in the NS posture. In contrast, muscle activity in the right RA was significantly higher in the ULC posture than in the NS posture. Muscle activity in the tight RA was significantly higher in the AOK posture, as compared to the NS posture, whereas activity in the left IO was significantly lower in the AOK posture, as compared to the NS posture. The right-left muscle activity ratios in the EO and IO showed significantly different patterns in the cross-legged postures, suggesting that asymmetrical right-left oblique muscle activity had occurred.
This study was done to evaluate the susceptibility, systemic effect, residual effect and control effect in each developmental stages of biotype Q of sweetpotato whitefly against insecticides, acetamiprid+spinetoram SC and dinotefuran SG. Two insecticides were showed similar activity against the eggs, and showed higher activity in acetamiprid+spinetoram SC against the nymph and adult. In systemic effect, two insecticides have a similar activity. It was showed higher activity in root zone systemic application than leaf zone systemic application. Residual effect was showed higher in acetamiprid+spinetoram SC (92%) than dinotefuran SG (44 %) at seven days after treatment. Control effect was showed all over 90 % activity at tree- and seven days after treatment. Therefore, these insecticides are expected to control the sweetpotato whitefly effectively.
This study was carried out to evaluate toxicities of two formulations (microemulsion, ME and wettable powder, WP) for acetamiprid+etofenprox against aphids (Aphis gossypii), thrips (Frankliniella occidentalis) on the cucumber greenhouse and whiteflies (Trialeurodes vaporariorum and Bemisia tabaci Qbiotype) on the tomato greenhouse. The activities of two formulations were evaluated by testing residual effect and toxicities against eggs, nymphs and adults of whiteflies in the laboratory, and control effect in the greenhouse against whiteflies, aphids and thrips. All trials were tested at the recommended concentration(RC) and a half concentration of RC of each formulation. In the laboratory trials against eggs and nymphs of whiteflies, the effect of ME was more effective than that of WP and showed more than 80% ovicidal activities, and 40%~60% larvicidal activities on the 3rd instars nymph of whiteflies at the recommended and its half concentrations. On the residual effect against the adults of the two whitefly species, WP formulation was more effective than ME and showed more than 70% mortality at the 5th day after treatments of recommended concentrations. In the field trials, the effects of ME against whiteflies and thrips were more excellent than those of WP. On the other hand, the effect of WP against aphids was more excellent. These results indicate that the formulation of insecticide can be played an important role in the control strategy of the pest in field.
DNA-based technology are about to revolutionize the analysis of population structures as well as the determination of individual indentities. Furthermore, the analysis of polymorphic DNA regions make it possible to reach detailed conclusions on family relationships of individual. Microsatellite loci are increasingly used in population genetic and evolutionary studies. Simple sequence repeats (SSRs) or microsatellites consisted of short tandem repeats (usually 1-6 nucleotide) have shown advantages over other markers. We report here the isolation and characterization of nine highly polymerphic microsatellite loci for phylogenetic and population genetic use in silkworm. Comparative analysis of diverse silkworm strains with microsatellite locus revealed several alleles and discriminative heterozygosity values. A list of primer sequences that tag each locus is provided. The usefulness of microsatellite markers can be expected to enhance the classification in silkworm.
We analyzed fault plane solutions of the recent twenty-two earthquakes which occurred from 2004 to 2006 in the central part of the Korean Peninsula by using P- and S-wave polarities along with SH/P amplitude ratios. The fault plane solution shows that strike-slip fault is dominant here, especially for the events with local magnitude equal to or greater than 3.0. However, some events with local magnitude less than 3.0 show normal fault or strike-slip fault with normal components. In the case of strike-slip fault, its orientation is almost in the direction of NNE-SSW to NE-SW almost parallel to the general trend of faults, while the compressional axis of the stress field trends ENE to E-W. The result is almost consistent with the stress field in and around the Korean peninsula, as reported previously. We cannot give any appropriate explanations to the normal faulting events along the western offshore and inland areas whether it is related to the local stress changes or tectonically unidentified extensional structures. Thus, an extension of investigations is desirable to clarify the cause of such phenomena.
In this study, alterations in whole proteome expression patterns in the head of Japanese medaka (Oryzias latipes) was investigated following acute or chronic exposure to benzo(a)pyrene (BaP) (25 μg L-1) for 48 hrs and 15 days, respectively. The
Changes in stress-associated biomolecules can be used as an important criterion for assessing the levels of environmental pollution because living organisms demonstrate contamination-stimulated stress responses. This study was conducted to determine the e
This study compared the pregnancy rates of Korean native donor cattle after either a timed artificial insemination (TAI) or embryo transfer (TET) following the synchronization of ovulation using a controlled internal drug release (CIDR) device together with estradiol benzoate (EB) and prostaglandin (). Fifty five cows and 8 heifers which had been previously used for embryo production were assigned to two treatments: (1) Thirty-two cattle received a CIDR device and 2 mg EB (Day 0), 25 mg injection at the time of CIDR removal on Day 7, and 1 mg EB injection on Day 8. All of the cattle received a TAI 30 h (Day 9) after the second EB injection (TAI group). (2) Thirty-one cattle received the same hormonal treatments as in the TAI group. The cattle with corpus luteum (CL) received a TET on Day 16 using frozen-thawed embryos (TET group). Ultrasonographic observations demonstrated that the proportion of cattle with synchronized ovulation on Day 10 and the concomitant formation of new CL on Day 13 did not differ between groups (p>0.05); the overall mean rates were 65.1 and 73.0%, respectively. The conception and pregnancy rates did not differ (p>0.05) between the TAI (12.5% and 12.5%) and TET groups (13.0% and 9.7%), respectively. We conclude that the pregnancy rate following TAI or TET in Korean native donor cattle was poor, which might be due in part to a poor synchrony of ovulation and concomitant CL formation.
A B. thuringiensis kurstaki was first discovered by H. Dulmage in 1970 and commercialized as a DipelTM due to powerful toxicity to various Lepidoptera. Previously we isolated B. thuringiensis kurstaki on the basis of plasmid DNA profiling and H-antigen serotyping. The aims of this study were to screen larvicidal activities and select the highly active B. thuringiensis isolates against the important polyphagous pests of mandarine oranges and vegetables. The colony forming unit (CFU/ml) of each of culture mixtures was determined to estimate the δ-endotoxin concentration. The bioassay against artificial diet-rearing insects was conducted by surface contamination methods using the Petri dishes specially designed and manufactured by SPL Lifesciences. The insecticidal activities to the natural diet-rearing insect were measured by the application of spore and crystal mixtures to the leaf discs of the chinese cabbage with Potter spray tower. The following insects were used for the larvicidal activities of B. thuringiensis isolates: beet armyworm Spodoptera exigua, diamondback moth Plutella xylostella, giant looper Ascotis selenaria, tobacco cutworm Spodoptera litura, and variegated cutworm Peridroma sucia.