Genomic and phylogenetic characterization of Shewanella xiamenensis isolated from giant grouper (Epinephelus lanceolatus) in Taiwan

Shewanella xiamenensis is an emerging pathogen causing intra‐abdominal infection and intestinal colonization. Epidemiologic clues suggest its role as a potential food‐borne zoonotic agent. To date, four genome sequences of S. xiamenensis have been made publicly available. All of them were isolated from water samples. In this study, we characterized the genome of a S. xiamenensis strain isolated from a giant grouper in Taiwan. The genome of S. xiamenensis ZYW1 is 4,827,717 bp in length and encodes 4,239 open reading frames. Its genomic sequence shares high homology with other S. xiamenensis strains. bla_OXA‐416 was identified. This is the first detection of S. xiamenensis in Taiwan. These genomic data and analyses contribute to our understanding of S. xiamenensis and may help to elucidate disease‐causing mechanisms in future studies.     

Conversion of Cortisone to Cortisol and Prostaglandin F2α Production by the Reproductive Tract of Cows at the Late Luteal Stage In Vivo

Previous in vitro studies demonstrated that bovine endometrium has the capacity to convert inactive cortisone to biologically active cortisol (Cr) and that Cr inhibits cytokine‐stimulated prostaglandin F_2α (PGF) production. This study was carried out to test the hypothesis that bovine reproductive tract has the capacity to convert cortisone to Cr in vivo and to evaluate the effects of intravaginal application of exogenous cortisone on uterine PGF secretion during the late luteal stage. The temporal relationships between PGF and Cr levels in uterine plasma were also determined. Catheters were inserted into jugular vein (JV), uterine vein (UV), vena cava caudalis (VCC) and aorta abdominalis (AA) of six cows on Day 15 of the oestrous cycle (ovulation = Day 0) for frequent blood collection. On Day 16, the cows were divided randomly into two groups and infused intravaginally with vaseline gel (10 ml; control; n = 3) or cortisone dissolved in vaseline gel (100 mg; n = 3). Blood samples were collected at ?2, ?1, ?0.5, 0, 0.5, 1, 1.5, 2, 3, 4, 5 and 6 h after treatments (0 h). Intravaginal application of cortisone increased plasma concentrations of Cr between 0.5 and 1.5 h in UV, at 0.5 h in VCC, at 1 h in JV and at 1.5 h in AA. The plasma concentrations of PGF in UV and of PGF metabolite in JV were greater at 0.5 and 1 h in the cortisone‐treated animals than in control animals. The levels of PGF in UV blood plasma decreased after Cr reached its highest levels. The overall findings suggest that the female reproductive tract has the capacity to convert cortisone to Cr in vivo. Based on the temporal changes of PGF and Cr levels in the uterine plasma, a biphasic response in PGF secretion was found to be associated to the Cr increase induced by the cortisone treatment at the late luteal stage in non‐pregnant cows.     

Using “Uterine Index” to diagnose embryonic death in mares

Embryonic death plays an important role in infertility in mares, and most of embryonic mortality occurs at an early stage (before day 40) of pregnancy. Previous investigations focused on B-mode sonographic images to determine abnormal pregnancy; however, no study has provided a quantitative and objective method to diagnose embryonic death. Here we developed a new index, “Uterine Index,” using color Doppler sonography to describe alterations of uterine blood flow in physiological and pathological gestations during early gestation. Six Trotter mares were used in this study. The pregnancies were interrupted with a prostaglandin F2α (PGF_2α) analog (tiaprost) at days 25, 30, and 40. Three gestations were investigated in each stage. After the PGF_2α administration, these mares were examined every 8 hours until the embryonic vesicles were not visible on ultrasound. In the control group, three pregnancies were examined daily from days 12 to 60. The embryo size was measured in B-mode sonography, and the blood flow in uterine arteries was examined in Doppler ultrasound. The resistance index (RI) and uterine index (UI) were calculated. In the control group, the RI values of uterine artery were lower in pregnant side compared with that of the non-pregnant side from day 15 on, and the difference became greater as the pregnancy advanced (P < .05). The UI was close to 0 before week 3 and increased to approximately 10 after week 4. In the PGF_2α-treated group, the UI values reduced from pregnancy level to approximately 0. As early as 32 hours before embryonic death, we observed a significant difference of UI values between control and treated mares. On the contrary, the embryo size of treated mares was not different from that of normal mares. Through the analysis of all recorded UI values, we suggest that the UI values 10 and 5 are good values for distinguishing normal pregnancy (UI >10) from embryonic death (UI < 5). If the UI values are located between 10 and 5, a reexamination at intervals of 1 to 3 days is recommended. Our findings demonstrate that the UI is a useful method to diagnose and predict embryonic death in mares by providing reliable and objective information.     

谈如何使警犬技术的独特作用得到充分发挥

随着警犬技术自身不断地发展和完善,使用效益逐步提高,警犬技术在公安工作中的独特作用也日益明显,但其独特作用是否已经得到充分发挥了呢?笔者认为,目前我国警犬技术的作用距"充分发挥"还相差甚远.主要表现为:作为证据仍未得到法律的确认,参与侦办"大案"多、忽视了对"小案"的侦办,在各地区发挥的作用不均衡.究其原因,笔者认为主要有以下三个方面.     

Dietary effects on egg production,egg‐hatching rate and female life span of the tropical calanoid copepod Acartia bilobata

Copepods are crucial source of live feeds in the aquaculture industry. In particular, several species of the genus Acartia are considered optimal prey for fish larvae. The species Acartia bilobata has excellent potential for marine larvae culture, as it is easy for mass culture. This study investigated the effects of various algal diets on the egg production and egg‐hatching rate of A. bilobata. The results indicated that the single‐species diet Isochrysis galbana was the most supportive diet for A. bilobata egg production and female life span in all treatments (egg production: 23.85 ± 0.70 eggs female^?1 day^?1 and female life span: 18.00 ± 1.45 days). Nannochloropsis oculata and Tetraselmis chui treatments gave markedly lower egg production and female life span as both single‐species and multiple‐species diets. For the egg hatching‐rate experiment, except for the T. chui treatment, which yielded a considerably lower hatching rate than the other diets, the hatching rate was only slightly affected by the algal diets. These results confirm that A. bilobata, a tropical brackish‐water copepod species, develops rapidly at 28°C and can produce a large number of eggs; therefore, it has considerable potential for larvae culture.     

LEYMUS AEMULIS (NEVSKI) TZVEL., A NEW RECORD FROM WEST CHINA -- ITS MORPHOLOGICAL AND CYTOLOGICAL OBSERVATIONS

<正> Leymus aemulis (Nevski) Tzvel. is newly recorded in China. The morphology and cytology of this species were studied. It has single spikelet per node different from other Chinese species of Leymtis. The chremosome number is 2n=28. The chromosome pairing was analysed at metaphase Ⅰ. Meiotic configuration was 0.11 Ⅰ+13.95 Ⅱ. It indicated that this species is an allo-tetraploid.     

Real-time, very-long-baseline interferometry based on the use of a communications satellite

The Hermes satellite, a joint Canadian-American program, has been used to provide a communication channel between radio telescopes in West Virginia and Ontario, for very-long-baseline interferometry (VLBI). This system makes possible instantaneous correlation of the data as well as a sensitivity substantially better than that of earlier VLBI systems, by virtue of a broader observational bandwidth. With the use of a geostationary communications satellite it is possible to eliminate the tape recorders and the most troublesome part of the postobservational data processing. A further possibility is the development of a phase-coherent interferometer.