Enhanced joint impact of western hemispheric precursors increases extreme El Niño frequency under greenhouse warming.

Sea surface temperature variability over the north tropical Atlantic (NTA) and over the subtropical northeast Pacific (SNP), which is referred to as the North Pacific Meridional Mode, during the early boreal spring is known to trigger El Niño-Southern Oscillation (ENSO) events. The future changes of the influence of those northwestern hemispheric precursors on ENSO are usually examined separately, even though their joint impacts significantly differ from the individual impacts. Here, we show that the impacts of both NTA and SNP on ENSO significantly increase under greenhouse warming and that the degrees of enhancement are closely linked. The wetter mean state over the off-equatorial eastern Pacific is a single contributor that controls the impacts of both NTA and SNP on ENSO. The enhanced joint impacts of the northwestern hemispheric precursors on ENSO increase the occurrences of extreme El Niño events and the ENSO predictability under greenhouse warming.

Southern Indian Ocean Dipole as a trigger for Central Pacific El Niño since the 2000s.

Despite decades of effort, predicting the El Niño-Southern Oscillation (ENSO) since the 2000s has become increasingly challenging. This is due to the weaker coupling between the ENSO and well-known precursors in tropical ocean basins, particularly in the Indian Ocean. Here we show that the Southern Indian Ocean Dipole (SIOD), which is characterized by an east-west-oriented sea surface temperature dipole pattern over the southern Indian Ocean, has become a key precursor of Central Pacific El Niño since the 2000s with a 14-month lead. The role of the SIOD in the subsequent year's ENSO is distinctive from the equatorial Indian Ocean Dipole mode in that it prolongs the ENSO period. The westward-shifted ENSO has sustained simultaneous SIOD events for longer periods since the 2000s, which leads to weak but persistent westerly anomalies over the western Pacific. This eventually results in the development of the Central Pacific El Niño in the subsequent year.

Frist observation and effect of fishery of seabed litter on sea bed by trawl survey Korea waters.

Fisheries activities for supplying marine productions were excessively overwhelming. Furthermore in the competitive industrialization, the impact on marine ecosystems and fisheries resources are severe due to the increase of various seabed litter such as plastic materials, styrofoam and plastic bottles and the deterioration of the marine environment. Despite these seriously situation, very few studies of some sea of Korea have been carried out on sedimentary waste fishing. Also some fisheries and there are few reports on plastics present on the seabed of around Korea. This study investigated the distribution of seabed litter collected from the seabed and characteristics of each area by using the trawl gear of the survey vessel from February to November 2018. The weight of all seabed litter collected during the investigation was 62,541.5 kg km-2, with a range of 0.2-15,019.7 kg km-2. The most amount of seabed litter was collected from sea block 106 in the South Sea, followed by sea blocks 76 and 82 in the East Sea. Through this study, which was conducted for the first time in all sea in around Korea, it can be used as basic data to understand the current status of seabed litter in the seabed and to establish effective policies at the led by the government.

Development of real-time PCR assay for genetic identification of the mottled skate, Beringraja pulchra.

The mottled skate, Beringraja pulchra is one of the commercially important fishes in the market today. However, B. pulchra identification methods have not been well developed. The current study reports a novel real-time PCR method based on TaqMan technology developed for the genetic identification of B. pulchra. The mitochondrial cytochrome oxidase subunit 1 (COI) nucleotide sequences of 29 B. pulchra, 157 skates and rays reported in GenBank DNA database were comparatively analyzed and the COI sequences specific to B. pulchra was identified. Based on this information, a system of specific primers and Minor Groove Binding (MGB) TaqMan probe were designed. The assay successfully discriminated in 29 specimens of B. pulchra and 27 commercial samples with unknown species identity. For B. pulchra DNA, an average Threshold Cycle (Ct) value of 19.1±0.1 was obtained. Among 27 commercial samples, two samples showed average Ct values 19.1±0.0 and 26.7±0.1, respectively and were confirmed to be B. pulchra based on sequencing. The other samples tested showed undetectable or extremely weak signals for the target fragment, which was also consistent with the sequencing results. These results reveal that the method developed is a rapid and efficient tool to identify B. pulchra and might prevent fraud or mislabeling during the distribution of B. pulchra products.

Spawning Characteristics and Artificial Hatching of Female Mottled Skate, Beringraja pulchra in the West Coast of Korea.

The gonadsomatic index (GSI) of mottled skate was the highest in April, GSI and HSI showed a reverse phase for its reproductive cycle. The fish had one pair of egg capsules, having 1 to 7 fertilized eggs, and spawned all the year round. When surveying the reproductive characteristics of females over 63 ㎝ in disc width, we found the spawning peak was between April to June, and the appearance ratio of egg capsules was the highest in May (32.1%). The eggs were hatched at 8°C, 13°C, 18°C, water temperature (12.8 to 24.2°C), and the best hatching temperature was 18°C. The number of fish hatched was 4 to 5 fish/egg capsules, and the hatching rate was 100%. The sex ratios of hatching larvae were 45.5% female and 54.5% male. Therefore this study will provide fundamental data and information for artificial reproduction of the mottled skate.

Rapid development of microsatellite markers with 454 pyrosequencing in a vulnerable fish, the mottled skate, Raja pulchra.

The mottled skate, Raja pulchra, is an economically valuable fish. However, due to a severe population decline, it is listed as a vulnerable species by the International Union for Conservation of Nature. To analyze its genetic structure and diversity, microsatellite markers were developed using 454 pyrosequencing. A total of 17,033 reads containing dinucleotide microsatellite repeat units (mean, 487 base pairs) were identified from 453,549 reads. Among 32 loci containing more than nine repeat units, 20 primer sets (62%) produced strong PCR products, of which 14 were polymorphic. In an analysis of 60 individuals from two R. pulchra populations, the number of alleles per locus ranged from 1-10, and the mean allelic richness was 4.7. No linkage disequilibrium was found between any pair of loci, indicating that the markers were independent. The Hardy-Weinberg equilibrium test showed significant deviation in two of the 28 single-loci after sequential Bonferroni's correction. Using 11 primer sets, cross-species amplification was demonstrated in nine related species from four families within two classes. Among the 11 loci amplified from three other Rajidae family species; three loci were polymorphic. A monomorphic locus was amplified in all three Rajidae family species and the Dasyatidae family. Two Rajidae polymorphic loci amplified monomorphic target DNAs in four species belonging to the Carcharhiniformes class, and another was polymorphic in two Carcharhiniformes species.

Aneurysm of sinus of valsalva dissecting into the interventricular septum after aortic valve replacement: diagnosis by echocardiography and magnetic resonance imaging and treatment with surgical sealant.

Aneurysm of the sinus of Valsalva that causes dissection of the interventricular septum is an extremely rare entity. In this report we describe a case of aneurysm of the sinus of Valsalva dissecting into the interventricular septum, from the base to mid septum, after aortic valve replacement. After the diagnosis was made by transthoracic echocardiography and magnetic resonance imaging, the patient was successfully treated with surgical sealant-mediated occlusion of the aneurysmal sac and cardiac resynchronization therapy used for the first time.

Culprit-Lesion-Only Versus Multivessel Revascularization Using Drug-Eluting Stents in Patients With ST-Segment Elevation Myocardial Infarction: A Korean Acute Myocardial Infarction Registry-Based Analysis.

BACKGROUND AND OBJECTIVES: In patients with ST-segment elevation myocardial infarction (STEMI) and multivessel disease, complete revascularization (CR) for non-culprit lesions is not routinely recommended. The aim of this study was to compare the clinical outcomes of multivessel compared with infarct-related artery (IRA)-only revascularization in patients undergoing primary percutaneous coronary intervention (PCI) for STEMI. SUBJECTS AND METHODS: From the Korean Acute Myocardial Infarction Registry (KAMIR) database, 1,094 STEMI patients with multivessel disease who underwent primary PCI with drug-eluting stents were enrolled in this study. The patients were divided into two groups: culprit-vessel-only revascularization (COR, n=827) group; multivessel revascularization, including non-IRA (MVR, n=267) group. The primary endpoint of this study included major adverse cardiac events (MACEs), such as death, myocardial infarction, or target or nontarget lesion revascularization at one year. RESULTS: There was no difference in clinical characteristics between the two groups. During the one-year follow-up, 102 (15.2%) patients in the COR group and 32 (14.2%) in the MVR group experienced at least one MACE (p=0.330). There were no differences between the two groups in terms of rates of death, myocardial infarction, or revascularization (2.1% vs. 2.0%, 0.7% vs. 0.8%, and 11.7% vs. 10.1%, respectively; p=0.822, 0.910, and 0.301, respectively). The MACE rate was higher in the incompletely revascularized patients than in the completely revascularized patients (15% vs. 9.5%, p=0.039), and the difference was attributable to a higher rate of nontarget vessel revascularization (8.6% vs. 1.8%, p=0.002). CONCLUSION: Although multivessel angioplasty during primary PCI for STEMI did not reduce the MACE rate compared with culprit-vessel-only PCI, CR was associated with a lower rate of repeat revascularization after multivessel PCI.

Massive left atrial calcification associated with mitral valve replacement.

Calcification of the left atrium can be observed in patients with a long-lasting rheumatic heart disease. However, massive calcification of the atrial wall, so called porcelain or coconut atrium is very rare and has been generally reported only as incidental radiographic findings. We report a case of massive and firm calcifications at the left atrium in patient who underwent mitral valve replacement.