Cijepni soj virusa zaraznog bronhitisa patogeniji je za pileće zametke od divljeg soja 2575/98.

An avian infectious bronchitis virus (IBV) strain 2575/98 was attenuated using serial chicken embryo passage to become a vaccine in Taiwan. The aim of this study was to investigate the replication ability, pathogenicity, and tissue tropism of the wild and vaccine strains in chicken embryos. The embryos were inoculated with different titers of wild and vaccine strains. Quantification of virus in allantoic fluid was evaluated using real time RT-PCR. The results showed that the vaccine strain replicated in higher titers than the wild strain, and caused embryo death so quickly that only a few dwarfisms occurred. The embryos inoculated with wild and vaccine strains had similar lesions that were confined primarily to the chorionallantoic membrane (CAM), liver, and kidneys. The immunohistochemical data showed that IBV was present predominantly in the lungs, kidneys, and CAM. Although both strains caused hepatic damage, very few virus antigens were detected in the hepatic tissue. The pathogenicity of the vaccine becomes higher in embryos although it is lower in chickens than its wild strain. The vaccine strain could be used as a possible new vaccine candidate for IBV control.Virus zaraznog bronhitisa peradi soj 2575/98 bio je oslabljen uzastopnim pasažama u pilećim zametcima da bi poslužio kao cijepni soj u Tajvanu. Cilj je ovog rada bio istražiti mogućnost umnožavanja, patogenost i tropizam terenskog i cijepnog soja u pilećim zametcima. Zametci su bili inokulirani cijepnim sojem različitog titra. Količina virusa u alantoisnoj tekućini bila je određena RT-PCR-om u stvarnom vremenu. Rezultati su pokazali da se cijepni soj umnažao u višem titru od divljeg soja i prouzročio uginuće zametaka tako brzo da se uspjelo razviti svega nekoliko kržljavih. U inokuliranih zametaka, bez obzira na divlji ili cijepni soj, razvile su se slične promjene pretežito na korioalantoisnoj opni, jetrima i bubrezima. Imunohistokemijski je dokazano da se virus zaraznog bronhitisa prvenstveno nalazio u plućima, bubrezima i korioalantoisnoj opni. Iako su oba soja prouzročila oštećenja jetara, neznatna količina virusnog antigena bila je dokazana u jetrenom tkivu. Patogenost cijepnog soja bila je u zametcima jača, a u pilićima slabija od divljeg soja. Cijepni soj bi se mogao rabiti kao mogući kandidat za proizvodnju novog cjepiva protiv zaraznog bronhitisa

New primers for methylation-specific polymerase chain reaction enhance specificity of detecting STAT1 methylation

AbstractObjectiveSignal transducer and activator of transcription (STAT)1 is a key tumor suppressor, which is always methylated in a variety of human cancers. However, nonspecific primers for the detection of specific promoter hypermethylation of STAT1 gene can lead to false-positive or false-negative results for gene methylation.Materials and MethodsWe designed new primers for the detection of STAT1 methylation and compared the sensitivities and specificities of these new primers with prior published primers by methylation-specific polymerase chain reaction (PCR) from ovarian clear cell carcinomas. The mRNA expression levels of STAT1 in these cancerous tissues were also evaluated by reverse-transcriptase PCR and correlated with the results of promoter methylation of STAT1 gene.ResultsNine (39%) of the 23 samples detected by the new primers and 13 samples (56%) detected by prior published primers showed STAT1 methylation. A direct DNA sequencing test revealed that four of the 13 samples (30.8%) showed false positivity for STAT1 methylation using the prior published primers. In contrast, none of the nine samples was false-positive for the detection of STAT1 methylation using the new primers. The new primers for the detection of STAT1 methylation showed 100% specificity and 100% sensitivity without false positivity.ConclusionSpecific primers for methylation-specific PCR are mandatory for the accurate detection of STAT1 gene methylation. Besides, specific primers can generate correct interpretation of STAT1 gene methylation, and its correlation with the clinicopathological characteristics and outcome of cancer patients

Exploring the value co-destruction model for on-line deviant behaviors of hotel customers

© 2019 Elsevier Ltd This study aims to build a value co-destruction model by exploring the online deviant behavior of hotel customers. Desire for revenge and desire for recovery are considered mediators. Hotel guests in notable Taiwan locations were surveyed via the Internet (no. = 601 valid responses). This study finds that negative emotion indirectly impacts negative electronic word of mouth (eWOM) with desire for revenge as a mediator. Furthermore, desire for recovery has the potential to mitigate the impact of negative emotion on negative eWOM. However, the desire for recovery is less intense than the desire for revenge. Based on these findings, this study concludes that emotion, by itself, does not result in action. Respondents only commit negative eWOM because they want to hurt the firm that wronged them. Respondents are also willing to entertain the idea of service recovery. However, desire for revenge is a stronger mediating factor

Supermassive Black Holes with High Accretion Rates in Active Galactic Nuclei. IV. Hβ\beta Time Lags and Implications for Super-Eddington Accretion

We have completed two years of photometric and spectroscopic monitoring of a large number of active galactic nuclei (AGNs) with very high accretion rates. In this paper, we report on the result of the second phase of the campaign, during 2013--2014, and the measurements of five new H$\beta$ time lags out of eight monitored AGNs. All five objects were identified as super-Eddington accreting massive black holes (SEAMBHs). The highest measured accretion rates for the objects in this campaign are $\dot{\mathscr{M}}\gtrsim 200$, where $\dot{\mathscr{M}}= \dot{M}_{\bullet}/L_{\rm Edd}c^{-2}$, $\dot{M}_{\bullet}$ is the mass accretion rates, $L_{\rm Edd}$ is the Eddington luminosity and $c$ is the speed of light. We find that the H$\beta$ time lags in SEAMBHs are significantly shorter than those measured in sub-Eddington AGNs, and the deviations increase with increasing accretion rates. Thus, the relationship between broad-line region size ($R_{_{\rm H\beta}}$) and optical luminosity at 5100\AA, $R_{_{\rm H\beta}}-L_{5100}$, requires accretion rate as an additional parameter. We propose that much of the effect may be due to the strong anisotropy of the emitted slim-disk radiation. Scaling $R_{_{\rm H\beta}}$ by the gravitational radius of the black hole, we define a new radius-mass parameter ($Y$) and show that it saturates at a critical accretion rate of $\dot{\mathscr{M}}_c=6\sim 30$, indicating a transition from thin to slim accretion disk and a saturated luminosity of the slim disks. The parameter $Y$ is a very useful probe for understanding the various types of accretion onto massive black holes. We briefly comment on implications to the general population of super-Eddington AGNs in the universe and applications to cosmology.Comment: 53 pages, 12 figures, 7 tables, accepted for publication in The Astrophysical Journa

Prognostic factors associated with the survival of oral and pharyngeal carcinoma in Taiwan

<p>Abstract</p> <p>Background</p> <p>In Taiwan, a distinct ethnic group variation in incidence and mortality rates has been suggested for most carcinomas. Our aim is to identify the role of prognostic factors associated with the survival of oral and pharyngeal carcinoma in Taiwan.</p> <p>Methods</p> <p>Taiwan Cancer Registry records of 9039 subjects diagnosed with oral and pharyngeal carcinoma were analyzed. The population was divided into three ethnic groups by residence, which were Taiwanese aborigines, Hakka and Hokkien communities. Five-year survival rates were estimated by Kaplan-Meier methods. Ethnic curves differed significantly by log-rank test; therefore separate models for Taiwanese aborigines, Hakka and Hokkien were carried out. The Cox multivariate proportional hazards model was used to examine the role of prognostic factors on ethnic survival.</p> <p>Results</p> <p>The five-year survival rates of oral and pharyngeal carcinoma were significantly poorer for Hokkien community (53.9%) and Taiwanese aborigines community (58.1%) compared with Hakka community (60.5%). The adjusted hazard ratio of Taiwanese aborigines versus Hakka was 1.07 (95%CI, 0.86–1.33) for oral and pharyngeal carcinoma mortality, and 1.16 (95%CI, 1.01–1.33) for Hokkien versus Hakka. Males had significantly poor prognosis than females. Subjects with tongue and/or mouth carcinoma presented the worst prognosis, whereas lip carcinoma had the best prognosis. Subjects with verrucous carcinoma had better survival than squamous cell carcinoma. Prognosis was the worst in elderly subjects, and subjects who underwent surgery had the highest survival rate.</p> <p>Conclusion</p> <p>Our study presented that predictive variables in oral and pharyngeal carcinoma survival have been: ethnic groups, period of diagnosis, gender, diagnostic age, anatomic site, morphologic type, and therapy.</p

Magnetic Silicon Fullerene

A metal-encapsulating silicon fullerene, Eu@Si20, has been predicted by density functional theory to be by far the most stable fullerene-like silicon structure. The Eu@Si20 structure is a dodecahedron with D2h symmetry in which the europium atom occupies the center site. The calculated results show that the europium atom has a large magnetic moment of nearly 7.0 Bohr magnetons. In addition, it was found that a stable "pearl necklace" nanowire, constructed by concatenating a series of Eu@Si20 units, with the central europium atom, retains the high spin moment. The magnetic structure of the nanowire indicates potential applications in the fields of spintronics and high-density magnetic storage

Calibration of Temperature in the Lower Stratosphere from Microwave Measurements Using COSMIC Radio Occultation Data: Preliminary Results

Accurate, consistent, and stable observations from different satellite missions are crucial for climate change detection. In this study, we use Global Positioning System (GPS) Radio Occultation (RO) data from the early phase of the FORMOSAT-3/Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) mission, which was successfully launched on 15 April 2006, to inter-calibrate Temperature in the Lower Stratosphere (TLS) taken from Advanced Microwave Sounding Unit (AMSU) microwave measurements from different satellites for potential improvements of stratospheric temperature trend analysis. Because of the limited number of COSMIC soundings in the early phase of the mission, these results are considered preliminary. In this study, we use COSMIC RO data to simulate microwave brightness temperatures for comparison with AMSU Ch9 measurements (e.g., TLS) on board NOAA15, 16, and 18. Excellent correlation was found between synthetic COSMIC brightness temperatures (Tbs) and Tbs from NOAA15, NOAA16, and NOAA18, respectively. However, systematic differences on the order of 0.7 to 2 K were found between COSMIC and AMSU observations over Antarctica. Our results demonstrate that synthetic COSMIC Tbs are very useful in identifying inter-satellite offsets among AMSU measurements from different satellites. To demonstrate the long-term stability of GPS RO data, we compare COSMIC dry temperature profiles to those from collocated CHAMP profiles, where CHAMP was launched in 2001. The fact that the CHAMPand COSMIC dry temperature difference between 500 and 10 hPa ranges from -0.35 K (at 10 hPa) to 0.25 K (at 30 hPa) and their mean difference is about -0.034 K demonstrates the long-term stability of GPS RO signals. In order to demonstrate the potential usage of the GPS RO calibrated AMSU Tbs to inter-calibrate other overlapping AMSU Tbs, we examine the uncertainty of the calibration coefficients derived from AMSU-GPS RO pairs. We found the difference between COSMIC calibrated AMSU Tbs and those from CHAMP to be in the range of __0.07 K with a 0.1 K standard deviation. This demonstrates the robustness of the calibration coefficients found from AMSU-GPS RO pairs and shows the potential to use the calibrated AMSU Tbs to calibrate other overlapping AMSU Tbs where no coincident GPS RO data are available