Anomalous pinch in the T-11M tokamak in an enhanced-collisionality regime

The formation of a peaked bell-shaped profile of the electron density n _e (r) in the T-11M tokamak (B _t=1 T, R/a = 0.7/0.2 m, I _p = 100 kA, t _shot ≤ 300 ms, Li and C limiters) was observed in Li experiments carried out in the near-plateau collisionality regime (the collisionality parameter at one-half of the minor radius was v* ≥ 0.5) under the conditions of low hydrogen recycling and intense hydrogen influx from the plasma edge. It is well known that peaked n _e (r) profiles are observed in collisionless regimes at v* values as low as 10^?1–10^?2 or in impurity-contaminated discharges, in which this effect can be attributed to the impurity accumulation on the plasma column axis. Moreover, a bell-shaped n _e (r) profile in discharges with low n _e can result from the ionization of hydrogen atoms at the column axis, where they arrive from the plasma edge due to cascade charge-exchange. In quasi-steady lithium discharges in T-11M, however, peaked n _e (r) profiles were observed at a relatively high central electron density n _e (0) and relatively high collision frequency, such that the influence of impurities on the n _e (r) profile could be ignored (Z _eff = 1.1±0.1). To explain this effect, one has to assume that the pinching of hydrogen ions in T-11M is anomalous. The lower estimate of the observed pinch velocity is 4 ± 1 m/s, which is three to five times higher than the velocity of the neoclassical (Ware) pinch, characteristic of these conditions. The work is devoted to the experimental study of this effect.     

Ion temperature profiles along a hydrogen diagnostic beam in a TORE SUPRA tokamak plasma

The active particle diagnostic technique is used to study the ion temperature at five spatial points along the path of a hydrogen diagnostic beam. The temperature of the main ion plasma component (deuterium ions) measured by this diagnostic technique along the beam path is compared with the temperature of carbon ions (C⁺⁵). A study is made of the following characteristic features of the behavior of the ion temperature profiles T_i in various TORE SUPRA operating modes: the formation of flat and even hollow T_i profiles in ohmic discharges with q ～3 at the plasma edge, the change in T_i profiles in ergodic divertor discharges, and the difference between the temperature of the bulk ions measured by the active particle diagnostic technique and the temperature of C⁺⁵ ions in the plasma region r/a>0.5. The features revealed are explained at a qualitative level.     

<Emphasis Type="Italic">Oceanobacillus gochujangensis</Emphasis> sp. nov., isolated from <Emphasis Type="Italic">gochujang</Emphasis> a traditional Korean fermented food

A Gram-stain-positive, polar flagella-containing, rod-shaped, obligate aerobic, endospore-forming bacterium, strain TK1655^T, was isolated from the traditional Korean food gochujang. The 16S rRNA sequence of strain TK1655^T was a member of the genus Oceanobacillus similar to that of the type strain of Oceanobacillus oncorhynchi subsp. incaldanensis DSM 16557^T (97.2%), O. oncorhynchi subsp. oncorhynchi JCM 12661^T (97.1%), O. locisalsi KCTC 13253^T (97.0%), and O. sojae JCM 15792^T (96.9%). Strain TK1655^T was oxidase and catalase positive. Colonies were circular, smooth, low convex, cream in colour, and measured about 0.5–1.0 mm in diameter. The range for growth was 20–40°C (optimal, 30°C), pH 6.0–10.0 (optimal, 7.0), and 2–16% (w/v) NaCl (optimal, 2%). Additionally, the cells contained meso-DAP, and the predominant isoprenoid quinone was MK-7. The complex polar lipids were consisted of diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylcholine (PC). The major cellular fatty acid components were iso-C_15:0, anteiso-C_15:0, iso-C_16:0, and anteiso-C_17:0, and the DNA G+C content was 40.5%. DNA-DNA relatedness of our novel strain and reference strain O. locisalsi KCTC 13253^T, O. oncorhynchi subsp. incaldanensis DSM 16557^T, O. oncorhynchi subsp. oncorhynchi JCM 12661^T was 45.7, 43.8, and 41.9%. From the results of phenotypic, chemotaxonomic, and phylogenetic analyses of strain TK1655^T, we propose the novel species Oceanobacillus gochujangensis sp. nov. The type strain is TK1655^T (=KCCM 101304^T =KCTC 33014^T =CIP 110582^T =NBRC 109637^T).     

Transition into the improved core confinement mode as a possible mechanism for additional electron heating observed in the lower hybrid current drive experiments at the FT-2 tokamak

In experiments on lower hybrid current drive (LHCD) carried out at the FT-2 tokamak, a substantial increase in the central electron temperature T _e (r = 0 cm) from 550 to 700 eV was observed. A complex simulation procedure is used to explain a fairly high LHCD efficiency and the observed additional heating, which can be attributed to a transition into the improved core confinement (ICC) mode. For numerical simulations, data obtained in experiments with deuterium plasma at 〈n _e 〉 = 1.6 × 10¹⁹ m^–3 were used. Simulations by the GRILL3D, FRTC, and ASTRA codes have shown that the increase in the density and central temperature is apparently caused by a significant suppression of heat transport in the electron component. The mechanism for transition into the improved confinement mode at r < 3 cm can be associated with the broadening of the plasma current channel due to the lower hybrid drive of the current carried by superthermal and runaway electrons. In this case, the magnetic shear s = (r/q)(dq/dr) in the axial region of the plasma column almost vanishes during the RF pulse. In this study, the effect of lower hybrid waves on the plasma parameters, resulting in a transition into the ICC mode, is considered. New experimental and calculated data are presented that evidence in favor of such a transition. Special attention is paid to the existence of a threshold for the transition into the ICC mode in deuterium plasma.     

<Emphasis Type="Italic">Halomonas tibetensis</Emphasis> sp. nov., isolated from saline lakes on Tibetan Plateau

Strains pyc13^T and ZGT13 were isolated from Lake Pengyan and Lake Zigetang on Tibetan Plateau, respectively. Both strains were Gram-negative, catalase- and oxidase-positive, aerobic, rod-shaped, nonmotile, and nonflagellated bacteria. Phylogenetic analysis based on 16S rRNA gene sequences showed that strains pyc13^T and ZGT13 belong to the genus Halomonas, with Halomonas alkalicola 56-L4-10aEn^T as their closest neighbor, showing 97.4% 16S rRNA gene sequence similarity. The predominant respiratory quinone of both strains was Q-9, with Q-8 as a minor component. The major fatty acids of both strains were C_18:1ω6c/C_18:1ω7c, C_16:1ω6c/C_16:1ω7c, C_16:0, and C_12:0 3OH. The polar lipids of both strains consisted of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, glycolipid, phospholipids of unknown structure containing glucosamine, and unidentified phospholipids. The DNA G + C content of pyc13^T and ZGT13 were 62.6 and 63.4 mol%, respectively. The DNA-DNA hybridization values of strain pyc13^T were 34, 41, 61, 35, and 35% with the reference strains H. alkalicola 56-L4-10aEn^T, H. sediminicola CPS11^T, H. mongoliensis Z-7009^T, H. ventosae Al12^T, and H. fontilapidosi 5CR^T, respectively. Phenotypic, biochemical, genotypic, and DNA-DNA hybridization data showed that strains pyc13^T and ZGT13 represent a new species within the genus Halomonas, for which the name H. tibetensis sp. nov. is proposed. The type strain is pyc13^T (= CGMCC 1.15949^T = KCTC 52660^T).     

Proposal of three novel species of soil bacteria, <Emphasis Type="Italic">Variovorax ureilyticus,Variovorax rhizosphaerae</Emphasis>, and <Emphasis Type="Italic">Variovorax robiniae</Emphasis>, in the family <Emphasis Type="Italic">Comamonadaceae</Emphasis>

Three novel bacterial strains (UCM-2^T, UCM-G28^T, and UCM-G35^T) were obtained while isolating soil bacteria for the development of antibiotics. Cells of these strains were Gram-negative, non-spore forming, motile by means of a single flagellum, and rod shaped. In all strains, the predominant isoprenoid quinone was ubiquinone-8 (Q-8). Cells contained C_16:0, summed feature 3 (C_16:1ω7c and/or C_16:1ω6c), summed feature 8 (C_18:1ω7c and/or C_18:1ω6c), and C_17:0 cyclo as the major fatty acids, and C_10:0 3-OH as the major hydroxy fatty acid. The polar lipid profiles of the three novel strains were dominated by diphosphatidylglycerol, phosphatidylethanolamine, and phosphatidylglycerol. The genomic DNA G + C contents of strains UCM-2^T, UCM-G28^T, and UCMG35^T were 67.5, 65.9, and 66.4 mol%, respectively. Phylogenetic analyses based on 16S rRNA sequences showed that strain UCM-2^T was most closely related to Variovorax soli NBRC 106424^T, whereas strains UCM-G28^T and UCM-G35^T were most similar to Variovorax ginsengisoli Gsoil 3165^T. Values indicating DNA-DNA hybridization between the novel isolates and closely related species in the genus Variovorax were lower than the 70% cut-off point. These phenotypic, chemotaxonomic, and phylogenetic data indicate that the three isolates should be classified as new members of the genus Variovorax, for which the names Variovorax ureilyticus sp. nov., Variovorax rhizosphaerae sp. nov., and Variovorax robiniae sp. nov. are proposed. The type strains are UCM-2^T (= KACC 18899^T = NBRC 112306^T), UCMG28^T (= KACC 18900^T = NBRC 112307^T), and UCM-G35^T (= KACC 18901^T = NBRC 112308^T), respectively.     

<Emphasis Type="Italic">Limnobacter humi</Emphasis> sp. nov., a thiosulfate-oxidizing,heterotrophic bacterium isolated from humus soil,and emended description of the genus <Emphasis Type="Italic">Limnobacter</Emphasis> Spring <Emphasis Type="Italic">et al.</Emphasis> 2001

Three Gram-negative, strictly aerobic, chemolithoheterotrophic bacterial strains, designated UCM-30, UCM-33, and UCM-39^T, were isolated in South Korea. Based on their 16S rRNA gene sequences, the three isolated strains were found to be similar to Limnobacter thiooxidans CS-K2^T (97.41–97.68%), Limnobacter litoralis KP1-19^T (95.55–95.76%), and various genera belonging to the class Betaproteobacteria (90.34–93.34%). DNA-DNA hybridization showed 79.3–83.9% similarity between the genomic DNA of UCM-39^T, UCM-30, and UCM-33, while the sequence similarity between UCM-39^T and L. thiooxidans KACC 13837T or L. litoralis LMG 24869T was 23.7% and 18.6%, respectively. The DNA G+C content of UCM 39T was 59.7 mol%, the major ubiquinone was Q-8, and the optimal oxidation rate was observed at 10 mM thiosulfate. The major fatty acids (≥ 10%) were summed features 3 (C_16:1 ω7c and/or C_16:1 ω6c) and 8 (C_18:1 ω7c and/or C_18:1 ω6c), and C_16:0. The major polar lipids (diphosphatidylglycerol, phosphatidylethanolamine, and phosphatidylglycerol) were found in all members of genus Limnobacter. Based on phenotypic, physiological, and phylogenetic analyses, the UCM-39T strain was found to be significantly distinct to represent a novel species affiliated to the genus Limnobacter. We propose to name it Limnobacter humi sp. nov. with the type strain UCM-39^T (=KACC 18574^T =NBRC 111650^T).     

Informative Value of Temperatures in Different Areas of the Human Body for Correcting Body Thermal Imbalance during Extravehicular Activities

Identification of noninvasive and informative sites on the body reflecting the development of body thermal imbalance during extravehicular activities (EVAs) is highly important for enhancing astronaut safety. Temperature changes were evaluated on several areas of the head (the mastoid fossa (T _mf ), the forehead (T _fo ), and the cheek (T _ch )) and on the fingers (T _fing ). Subjects were dressed in a multicompartment liquid cooling/warming garment. Studies I and II consisted of different combinations of hood versus garment cooling or warming imposed across stages; studies III and IV involved sagittally divided cooling or warming regimes with the hood worn (study III) or with the head uncovered (study IV). In studies I and II, T _mf significantly (P < 0.05) differed between stages 2, when the head was cooled and the rest of the body heated, and 3, when the head was heated and the rest of the body cooled. The T _mf changes were consistent with the thermal conditions imposed on the head but not reflective of the developing body heat deficit. In study III, the T _mf at stages 2 and 3 on the right or the left followed the thermal conditions on the ipsilateral side of the body (P < 0.01). In study IV, T _fing showed no significant differences across stages. In studies I–IV, T _fing showed consistent changes across stages (P < 0.05), reflecting the developing body heat deficit. In all studies, there were no significant differences in rectal temperature (T _re ) across stages. T _mf and temperatures at other head skin sites did not respond in accordance with the actual intensity of a heat or cold flux from the garment and were not reflective of the overall development of body thermal imbalance. T _fing was a more adequate indicator of initial thermal destabilization and provided information that would be useful for monitoring the thermal balance and comfort during EVAs.     

<Emphasis Type="Italic">Viridibacterium curvum</Emphasis> gen. nov., sp. nov., isolated from freshwater

A Gram stain-negative, yellowish green-pigmented, facultatively anaerobic, motile, curved rod-shaped bacterium designated as strain JJ016^T was isolated from an artificial lake in South Korea, and characterized using a polyphasic approach. The 16S rRNA gene sequence of strain JJ016^T indicated that the isolate belonged to the family Rhodocyclaceae and exhibited 95.0% identity to Uliginosibacterium gangwonense 5YN10-9^T. The major cellular fatty acids of the novel strain were summed feature 3 (C_16:1 ω6c and/or C_16:1 ω7c), C_16:0, C_14:0, and summed feature 8 (C_18:1 ω7c and/or C_18:1 ω6c). The DNA G+C content of strain JJ016^T was 61.9 mol%. The major respiratory quinone and major polar lipid of strain JJ016^T were ubiquinone-8 and phosphatidylethanolamine, respectively. Based on the morphological and physiological properties and the biochemical evidence presented, we concluded that strain JJ016^T represents a novel species of a new genus in the family Rhodocyclaceae, for which the name Viridibacterium curvum gen. nov., sp. nov. is proposed. The type strain is JJ016^T (=KACC 16899^T =JCM 18715^T).     

Polymorphism in promoter regions of matrix metalloproteinases (<Emphasis Type="Italic">MMP1</Emphasis>, <Emphasis Type="Italic">MMP9</Emphasis>, and <Emphasis Type="Italic">MMP12</Emphasis>) in chronic obstructive pulmonary disease patients

Our studies have shown that the genotype and allele frequencies of polymorphisms G(?1607)GG of MMP1 gene, C(?1562)T of MMP9 gene, and A(?82)G of MMP12 gene do not significantly differ in the samples of chronic obstructive pulmonary disease (COPD) patients (N = 318) and healthy controls (N = 319) dwelling in Bashkortostan Republic. However, association of (?1562)T allele of the MMP9 gene with the severity of COPD disease progression has been revealed. In COPD patients at stage 4 of the disease, the frequency of allele T was significantly higher that in patients with the stages 2 and 3 (15.89% versus 8.38%; χ² = 7.804; d.f. = 1; P = 0.005; OR = 2.06 95% CI 1.22–3.49). The distribution of the genotype frequencies of C(?1562)T polymorphism of MMP9 gene significantly differed between the patients with various COPD severity (χ² = 9.849; d.f. = 2; P = 0.007). The individuals with rare genotype TT were revealed only among patients with severe COPD form (3.97% versus 0%; χ² = 4.78; P = 0.029; P _cor = 0.058). Analysis of this polymorphism in patients with early COPD onset (younger than 55 years old) has shown a significant increase in the allele T frequency in the group of patients with severe COPD (stage 4 according to GOLD) compared to the patients of the same age but with less severe COPD progression (χ² = 5.26; d.f. = 1; P = 0.022). As the major clinical characteristics of stage 4 COPD is the development of pulmonary emphysema as well as bronchial walls deformation, we suggest that the increased expression of MMP9 gene caused by genetic polymorphism in the gene promoter is important in the early development of serious complications of the disease.     

<Emphasis Type="Italic">Azohydromonas riparia</Emphasis> sp. nov. and <Emphasis Type="Italic">Azohydromonas ureilytica</Emphasis> sp. nov. isolated from a riverside soil in South Korea

White and pale yellow coloured bacteria were isolated from the riverside soil, Daejeon, South Korea, and were designated UCM-11^T, UCM-F25, and UCM-80^T. We found that all strains were able to reduce nitrate, and the cells were aerobic and motile. The DNA G+C contents of UCM-11^T, UCM-F25, and UCM-80^T were between 68.9 to 71.2 mol% and the main ubiquinone was observed as Q-8. Based on16S rRNA gene sequences, strains UCM-11^T and UCM-F25 were found to closely match with Azohydromonas australica IAM 12664^T (98.48–98.55%), and the strain UCM-80^T was the closest match with Azohydromonas lata IAM 12599^T (98.34%). The presence of summed feature 3 (C_16:1 ω7c and/or C_16:1 ω6c), C_16:0, summed feature 8 (C_18:1 ω7c and/or C_18:1 ω6c) as well as twokinds of hydroxyfatty acids consisting of C_10:0 3-OH and C_12:0 2-OH, and branched fatty acids containing C_16:0 iso and C_17:0 cyclo were detected in all the strains. Phosphatidylethanolamine was a major polar lipid. DNA–DNA relatedness confirmed UCM-11^T, UCM-F25 and UCM-80^T as novel members of the genus Azohydromonas. Based on the morphological, physiological, biochemical and genotypic characteristics, we suggest that strains UCM-11^T, UCM-F25, and UCM-80^T represent novel species within the genus Azohydromonas. The names Azohydromonas riparia sp. nov., and Azohydromonas ureilytica sp. nov. are proposed for the type strains UCM-11^T (=KACC 18570^T =NBRC 111646^T) and UCM-80^T (=KACC 18576^T =NBRC 111658^T), respectively.     

Taxonomic description and draft genome of <Emphasis Type="Italic">Pseudomonas sediminis</Emphasis> sp. nov., isolated from the rhizospheric sediment of <Emphasis Type="Italic">Phragmites karka</Emphasis>

The taxonomic position of a Gram-stain-negative, rod-shaped bacterial strain, designated PI11^T, isolated from the rhizospheric sediment of Phragmites karka was characterized using a polyphasic approach. Strain PI11^T could grow optimally at 1.0% NaCl concentration with pH 7.0 at 30°C and was positive for oxidase and catalase but negative for hydrolysis of starch, casein, and esculin ferric citrate. Phylogenetic analysis of 16S rRNA gene sequences indicated that the strain PI11^T belonged to the genus Pseudomonas sharing the highest sequence similarities with Pseudomonas indoloxydans JCM 14246^T (99.72%), followed by, Pseudomonas oleovorans subsp. oleovorans DSM 1045^T (99.29%), Pseudomonas toyotomiensis JCM 15604^T (99.15%), Pseudomonas chengduensis DSM 26382^T (99.08%), Pseudomonas oleovorans subsp. lubricantis DSM 21016^T (99.08%), and Pseudomonas alcaliphila JCM 10630^T (99.01%). Experimental DNA-DNA relatedness between strain PI11^T and P. indoloxydans JCM 14246^T was 49.4%. The draft genome of strain PI11^T consisted of 4,884,839 bp. Average nucleotide identity between the genome of strain PI11^T and other closely related type strains ranged between 77.25–90.74%. The polar lipid pattern comprised of phosphatidylglycerol, diphosphatidylglycerol, and phosphatidylcholine. The major (> 10%) cellular fatty acids were C_18:1ω6c/ω7c, C_16:1ω6c/ω7c, and C_16:0. The DNA G + C content of strain PI11^T was 62.4 mol%. Based on the results of polyphasic analysis, strain PI11^T was delineated from other closely related type strains. It is proposed that strain PI11^T represents represents a novel species of the genus Pseudomonas, for which the name Pseudomonas sediminis sp. nov. is proposed. The type strain is PI11^T (= KCTC 42576^T = DSMZ 100245^T).     

<Emphasis Type="Italic">Corynebacterium defluvii</Emphasis> sp. nov., isolated from Sewage

A Gram-positive, aerobic, non-motile, rod-shapeds, catalase-positive, and oxidase-negative strain, designated Y49^T, was isolated from sewage collected from Jilin Agricultural University, China. It grew at 20–40°C (optimum at 30°C), at pH 6.0–8.0 (optimum at 7.0) and at 0–1.0% sodium chloride (optimum at 0%). The major isoprenoid quinone was menaquinone-8 (MK-8) and the polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylmethylethanolamine, four unidentified lipids, and two unidentified aminolipids. The peptidoglycan was meso-diaminopimelic acid. The cell-wall sugars were galactose, arabinose, and glucose. The fatty acids were C_9:0, C_16:0, C_16:1 ω9c, C_17:1 ω9c, C_18:3 ω6c (6,9,12), C_18:1 ω9c, and C_18:0. The DNA G+C content was 51.4 mol%. Based on the 16S rRNA gene sequence analysis, the nearest phylogenetic neighbors of strain Y49^T were Corynebacterium efficiens DSM 44549^T (97.5%), Corynebacterium callunae DSM 20147^T (97.2%), Corynebacterium deserti GIMN 1.010^T (96.8%), Corynebacterium glutamicum ATCC 13032^T (96.4%), and other species belonging to this genus (92.3–95.4%). The DNA-DNA relatedness value between strain Y49^T and C. efficiens DSM 44549^T, C. callunae DSM 20147^T, C. deserti GIMN1.010^T, and C. glutamicum ATCC 13032^T was 25.5±2.0%, 21.1±1.0%, 16.5±0.5%, and 13.5±0.9%, respectively. Based on the phylogenetic analysis, chemotaxonomic data, physiological characteristics and DNA-DNA hybridization data, strain Y49^T represents a novel species of the genus Corynebacterium, for which the name Corynebacterium defluvii sp nov. is proposed. The type strain is Y49^T (= KCTC 39731^T =CGMCC 1.15506^T).     

<Emphasis Type="Italic">Roseovarius tibetensis</Emphasis> sp. nov., a halophilic bacterium isolated from Lake LongmuCo on Tibetan Plateau

Two Gram-stain negative halophilic strains, designated as LM2^T and LM4, were isolated from Lake LongmuCo on Tibetan Plateau. These two strains were aerobic, catalaseand oxidase-positive, nonmotile and rod-shaped organisms. Phylogenetic analysis based on 16S rRNA gene sequences indicated that LM2^T and LM4 belong to the genus Roseovarius, with Roseovarius tolerans EL-172^T (97.3% and 97.4% 16S rRNA gene sequence similarity, respectively) and Roseovarius azorensis SSW084^T (95.5% and 95.6% 16S rRNA gene sequence similarity, respectively) as their closest neighbors. Q-10 was the sole respiratory quinone of these two strains. The major fatty acids were C_18:1ω7c/C_18:1ω6c, C_16:0, C_19:0 cyclo ω8c, and 11-methyl C_18:1ω7c. The polar lipids included phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phospholipid of unknown structure containing glucosamine, and unidentified aminolipid. The DNA G + C content was between 64.2 and 64.5 mol%. DNA-DNA hybridization showed 96.7% relatedness between LM2^T and LM4, 24.9% relatedness between LM2^T and R. tolerans EL-172^T, and 36.3% relatedness between LM4 and R. tolerans EL-172^T. Based on phylogenetic analysis, DNA-DNA hybridization, a range of physiological and biochemical characteristics, LM2^T and LM4 belong to the same species and were clearly distinguished from the type strains of the genus Roseovarius. It was evident that LM2^T and LM4 could be classified as a novel species of the genus Roseovarius, for which the name Roseovarius tibetensis sp. nov. is proposed. The type strain is LM2^T (= CGMCC 1.16230^T = KCTC 62028^T).     

Hydrothermal time analysis of watermelon (<Emphasis Type="Italic">Citrullus vulgaris</Emphasis> cv. ‘Crimson sweet’) seed germination

This study evaluated the ability of a hydrothermal time model (HTT) to describe the kinetics of watermelon (Citrullus vulgaris cv. ‘Crimson sweet’) seed germination under different temperatures (T) and water potentials (ψ) and also to determine the cardinal temperatures of watermelon. Results indicated that ψ influenced germination rate and germination percentage. For this seed lot, cardinal temperatures were 10 °C for T _b, 28.34 °C for T _o and 40.8 °C for T _c in the control (0 MPa) treatment. There was a decrease in hydrotime constant (θ _H) when T was increased to T _o and then remained constant at supra-optimal temperatures (30 MPah^?1). Also, at temperatures above T _o, ψ _b(50) values increased linearly with T. The k _T value (the slope of the relationship between ψ _b(50) and T exceeds T _o) of this seed lot was calculated as 0.076 MPa°Ch^?1. Results this study show that when the HTT model is applied, it can accurately describe ψ _b(g) and the course of germination around Ts (R ² = 0.82). Moreover, the ψ _b(50) was estimated to be ?0.96 MPa based on this model. Consequently, the germination response of watermelon for all Ts and ψs can be adequately described by the HTT model and enabling it to be used as a predictive tool in watermelon seed germination simulation models.     

<Emphasis Type="Italic">Flavobacterium parvum</Emphasis> sp. nov., isolated from soil polluted by sewer water

A novel Gram-stain-negative, motile by means of gliding, and short rod-shaped bacterium, designated HS916T, was isolated from soil polluted by sewer water in Cheonan-si, South Korea. Growth occurred at 10–35°C (optimum 30°C), pH 6.0–8.0 (optimum pH 7.0), and 0–1% sodium chloride (NaCl, w/v). Based on similarities of 16S rRNA gene sequences, strain HS916^T was closely related to members of the genus Flavobacterium, exhibiting the highest sequence similarities with Flavobacterium glycines Gm-149^T (96.4%), followed by F. granuli Kw05^T (96.3%), F. fluminis 3R17^T (96.3%), F. aquicola TMd3a3^T (96.2%), and F. nitratireducens N1^T (96.2%). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain HS916T was placed in a monophyletic cluster with F. nitratireducens N1^T and F. fluminis 3R17^T. The predominant fatty acids (> 5% of the total) of strain HS916^T were iso-C_15:0, anteiso-C_15:0, iso-C_15:0 3-OH, C_17:1ω6с, C_16:0 3-OH, iso-C_17:0 3-OH, and summed feature 3 (C_16:1ω7с and/or C_16:1ω6с). The major polar lipids of the strain comprised phosphatidylethanolamine, unidentified aminolipids, and five unidentified lipids. The predominant respiratory quinone and the major polyamine were menaquinone-6 (MK-6) and symhomospermidine, respectively. The DNA G + C content of strain HS916^T was 34.9 mol%. Based on polyphasic analyses, strain HS916^T represents a novel species belonging to the genus Flavobacterium, for which the name Flavobacterium parvum sp. nov. is proposed. The type strain is HS916T (= KACC 19448^T = JCM 32368^T).     

<Emphasis Type="Italic">Spirosoma lituiforme</Emphasis> sp. nov., isolated from soil

A Gram-staining-negative, non-motile, curved rod-shaped, aerobic bacterium, designated S1-2-4^T, was isolated from soil in Jeollabuk-do province, Republic of Korea, and was characterized taxonomically using a polyphasic approach. Comparative 16S rRNA gene sequence analysis showed that strain S1-2-4^T was a member of the family Cytophagaceae and most closely related to ‘Spirosoma radiotolerans’ DG5A (97.2%), Spirosoma fluviale MSd3^T (96.4%), and Spirosoma linguale DSM 74^T (96.3%). The genomic DNA G + C content of strain S1-2-4^T was 49.7 mol%. The major fatty acids were summed feature 3 (C_16:1ω7c/C_16:1ω6c), C_16:1ω5c, and C_16:0, and the major polar lipid was phosphatidylethanolamine. MK-7 was the predominant respiratory quinone. Phenotypic and chemotaxonomic data supported the affiliation of strain S1-2-4^T with the genus Spirosoma. DNA-DNA hybridization between strain S1-2-4^T and ‘Spirosoma radiotolerans’ showed relatively low DNA-DNA relatedness (31%). Strain S1-2-4^T could be distinguished from its closest phylogenetic neighbors based on its phenotypic, genotypic, and chemotaxonomic features. Therefore, strain S1-2-4^T represents a novel member of the genus Spirosoma, for which the name Spirosoma lituiforme sp. nov. is proposed. The type strain is S1-2-4^T (= KCTC 52724^T = JCM 32128^T).     

<Emphasis Type="Italic">Hymenobacter daeguensis</Emphasis> sp. nov. isolated from river water

A Gram-stain-negative, non-motile, non-spore-forming, rod-shaped, aerobic bacterial strain, designated 16F3Y-2^T, was isolated from the Han River, South Korea, and was characterized taxonomically using a polyphasic approach. Comparative 16S rRNA gene sequence analysis showed that strain 16F3Y-2^T belonged to the family Cytophagaceae in the phylum Bacteroidetes and was most closely related to ‘Hymenobacter terrae’ DG7A (98.01%), H. soli PB17^T (97.26%), H. glaciei VUG-A130^T (96.78%), H. antarcticus VUG-A42aa^T (96.72%), H. ruber PB156^T (96.61%), and H. saemangeumensis GSR0100^T (95.77%). The G+C content of the genomic DNA of strain 16F3Y-2^T was 62.9 mol%. The isolate contained MK-7 as the predominant respiratory quinone, and summed feature 3 (C_16:1 ω7c/C_16:1 ω6c; 35.5%), C_15:0 iso (16.9%), C_16:1 ω5c (10.9%), and C_15:0 anteiso (9.9%) as major fatty acids. The major polar lipid was phosphatidylethanolamine. Phenotypic and chemotaxonomic data supported the affiliation of strain 16F3Y-2^T with the genus Hymenobacter. However, strain 16F3Y-2^T exhibited relatively low levels of DNA-DNA relatedness with ‘H. terrae’ KCTC 32554 (44.1%) and H. soli KCTC 12607^T (24.3%), clearly indicating that the isolate constitutes a new genospecies. Strain 16F3Y-2^T could be differentiated from its phylogenetic neighbors on the basis of several phenotypic, genotypic, and chemotaxonomic features. Therefore, strain 16F3Y-2^T represents a novel species in the genus Hymenobacter, for which the name Hymenobacter daeguensis sp. nov. is proposed. The type strain is 16F3Y-2^T (=KCTC 52537^T =JCM 31654^T).     

<Emphasis Type="Italic">Pedobacter aquicola</Emphasis> sp. nov., isolated from freshwater

A non-motile, pink-pigmented bacterial strain designated IMCC25679^T, was isolated from freshwater Lake Chungju of Korea. Phylogenetic trees based on 16S rRNA gene sequences showed that the strain IMCC25679^T formed a lineage within the genus Pedobacter. The strain IMCC25679^T was closely related to Pedobacter daechungensis Dae 13^T (96.4% sequence similarity), Pedobacter rivuli HME8457^T (95.3%) and Pedobacter lentus DS-40^T (94.3%). The major fatty acids of IMCC- 25679^T were iso-C_15:0, iso-C_16:0 and summed feature 3 (comprising C_16:1ω6c and/or C_16:1ω7c). The major respiratory quinone was MK-7. The major polar lipids were phosphatidylethanolamine (PE), an unidentified sphingolipid (SL), an unidentified aminolipid (AL) and three unidentified polar lipids (PL). The DNA G + C content of IMCC25679^T was 32.2 mol%. Based on the evidence presented in this study, the strain IMCC25679^T represents a novel species within the genus Pedobacter, with the proposed name Pedobacter aquicola, sp. nov. The type strain is IMCC25679^T (= KACC 19486^T = NBRC113131^T).     

<Emphasis Type="Italic">Arcobacter acticola</Emphasis> sp. nov., isolated from seawater on the East Sea in South Korea

A Gram-stain-negative, facultative aerobic, non-flagellated, and rod-shaped bacterium, designated AR-13^T, was isolated from a seawater on the East Sea in South Korea, and subjected to a polyphasic taxonomic study. Strain AR-13^T grew optimally at 30°C, at pH 7.0–8.0 and in the presence of 0–0.5% (w/v) NaCl. The phylogenetic trees based on 16S rRNA gene sequences showed that strain AR-13^T fell within the clade comprising the type strains of Arcobacter species, clustering coherently with the type strain of Arcobacter venerupis. Strain AR-13^T exhibited 16S rRNA gene sequence similarity values of 98.1% to the type strain of A. venerupis and of 93.2–96.9% to the type strains of the other Arcobacter species. Strain AR-13^T contained MK-6 as the only menaquinone and summed feature 3 (C_16:1ω7c and/or C_16:1ω6c), C_16:0, C_18:1ω7c, and summed feature 2 (iso-C_16:1 I and/or C_14:0 3-OH) as the major fatty acids. The major polar lipids detected in strain AR-13^T were phosphatidylethanolamine, phosphatidylglycerol, and one unidentified aminophospholipid. The DNA G+C content was 28.3 mol% and its mean DNA-DNA relatedness value with the type strain of A. venerupis was 21%. Differential phenotypic properties, together with its phylogenetic and genetic distinctiveness, revealed that strain AR-13^T is separated from recognized Arcobacter species. On the basis of the data presented, strain AR-13^T is considered to represent a novel species of the genus Arcobacter, for which the name Arcobacter acticola sp. nov. is proposed. The type strain is AR-13^T (=KCTC 52212^T =NBRC 112272^T).