Genomic sequence of temperate phage Smp131 of Stenotrophomonas maltophilia that has similar prophages in xanthomonads

Stenotrophomonas maltophilia is a ubiquitous Gram-negative bacterium previously named as Xanthomonas maltophilia. This organism is an important nosocomial pathogen associated with infections in immunocompromised patients. Clinical isolates of S. maltophilia are mostly resistant to multiple antibiotics and treatment of its infections is becoming problematic. Several virulent bacteriophages, but not temperate phage, of S. maltophilia have been characterized

Familial aggregation and heritability of schizophrenia and co-aggregation of psychiatric illnesses in affected families

Strong familial aggregation of schizophrenia has been reported but there is uncertainty concerning the degree of genetic contribution to the phenotypic variance of the disease. This study aimed to examine the familial aggregation and heritability of schizophrenia, and the relative risks (RRs) of other psychiatric diseases, in relatives of people with schizophrenia using the Taiwan National Health Insurance Database. The study population included individuals with affected first-degree or second-degree relatives identified from all beneficiaries (n = 23 422 955) registered in 2013. Diagnoses of schizophrenia made by psychiatrists were ascertained between January 1, 1996 and December 31, 2013. Having an affected co-twin, first-degree relative, second-degree relative, or spouse was associated with an adjusted RR (95% CI) of 37.86 (30.55-46.92), 6.30 (6.09-6.53), 2.44 (1.91-3.12), and 1.88 (1.64-2.15), respectively. Compared with the general population, individuals with one affected first-degree relative had a RR (95% CI) of 6.00 (5.79-6.22) and those with 2 or more had a RR (95% CI) of 14.66 (13.00-16.53) for schizophrenia. The accountability for the phenotypic variance of schizophrenia was 47.3% for genetic factors, 15.5% for shared environmental factors, and 37.2% for non-shared environmental factors. The RR (95% CI) in individuals with a first-degree relative with schizophrenia was 3.49 (3.34-3.64) for mood disorders and 3.91 (3.35-4.57) for delusional disorders. A family history of schizophrenia is therefore associated with a higher risk of developing schizophrenia, mood disorders, and delusional disorders. Heritability and environmental factors each account for half of the phenotypic variance of schizophrenia

Serologic and Molecular Biologic Methods for SARS-associated Coronavirus Infection, Taiwan

Severe acute respiratory syndrome (SARS) has raised a global alert since March 2003. After its causative agent, SARS-associated coronavirus (SARS-CoV), was confirmed, laboratory methods, including virus isolation, reverse transcriptase–polymerase chain reaction (RT-PCR), and serologic methods, have been quickly developed. In this study, we evaluated four serologic tests ( neutralization test, enzyme-linked immunosorbent assay [ELISA], immunofluorescent assay [IFA], and immunochromatographic test [ICT]) for detecting antibodies to SARS-CoV in sera of 537 probable SARS case-patients with correlation to the RT-PCR . With the neutralization test as a reference method, the sensitivity, specificity, positive predictive value, and negative predictive value were 98.2%, 98.7%, 98.7%, and 98.4% for ELISA; 99.1%, 87.8%, 88.1% and 99.1% for IFA; 33.6%, 98.2%, 95.7%, and 56.1% for ICT, respectively. We also compared the recombinant-based western blot with the whole virus–based IFA and ELISA; the data showed a high correlation between these methods, with an overall agreement of >90%. Our results provide a systematic analysis of serologic and molecular methods for evaluating SARS-CoV infection

The epidemiologically truly disadvantaged: Examining childhood undervaccination in the United States, 1991-1993.

The epidemiologically truly disadvantaged: Examining childhood undervaccination in the United States, 1991-1993

Application of freezing crystallized enrichment coupled with hollow fiber supported liquid phase microextraction and GC/ECD to analyse aqueous phenols

酚類化合物被檢測出對人體健康有嚴重的危害，其中2,4-氯酚(DCP)、2,4,6-三氯酚(TCP)及五氯酚(PCP)皆被美國環保署公告為129種優先的列管毒物中，所以對氯酚類化合物的監測日益受到重視。傳統分析方法中關於氯酚類化合物前處理之步驟過於繁雜，且需使用大量的有機溶劑，易對人體造成危害及環境上的污染，因此樣品前處理的技術對於分析方法來說顯為重要。因此本研究開發出一種新的前處理技術，以結晶濃縮/液相微萃取的方式結合氣相層析儀，分析水樣中的氯酚類化合物，以達成簡化前處理萃取濃縮的過程。結晶濃縮萃取之原理主要以結晶的角度切入，因為結晶是純質為從一均勻相中所析出高純度之固體，相對而言在水中分析物為不純物，利用此特性並以水結晶的方式，讓分析物緩慢的往中心聚集，並利用中空纖維中的溶劑萃取，使之分析物能達到萃取和濃縮的效果。於萃取完成後，將萃取溶劑定量進入氣相層析儀進行偵測並結合電子捕捉偵檢器。實驗中探討影響萃取因素，並將此萃取方法應用於真實樣品。實驗結果顯示，以冷凍結冰溫度為-20℃，萃取時間為30分鐘，正辛醇作萃取溶濟，萃取溶液pH為2且不添加任何鹽類，可達較好的萃取效率。以最佳條件進行氯酚類分析，其濃度範圍為0.2~200 µg/L，相對標準偏差在11％以內，偵測極限為DCP 0.52 µg/L、TCP 0.03 µg/L、TeCP 0.02 µg/L、PCP 0.03 µg/L，將此方法應用於真實樣品中氯酚類化合物分析時，其回收率在77.96~110 % 之間，因此以結晶濃縮/液相微萃取技術結合氣相層析儀，偵測水樣中微量氯酚化合物，是一裝置及操作簡便、價格便宜、使用少量有機溶劑，亦有良好的再現性與靈敏度之新方法。The purpose of this study is to detect chlorophenols in water by developing a new technique of sample pretreatment. This study applied the freezing crystallization coupled with liquid phase microextraction and gas chromatography-electron capture detector to analyse the aqueous phenols. The method of liquid-phase microextraction (LPME) is using a small volume of organic solvent to impregnate with the hollow fiber, which was held by the needle of a conventional GC syringe. In this process, the hollow fiber impregnating with solvent was immersed in the aqueous sample, then using freezing crystallization to enrich the analytes and then dissolved in the organic solvent. After the compounds were collected, they were injected and analyzed by GC/ECD. The parameters affecting the extraction efficiency such as the temperature for freezing crystallization, the pH value of the solution and the time of extraction were investigated. The optimum condition of extraction efficiency for CPs in aqueous matrix was obtained by using octanol as extract solvent, the sample solution at pH 2 and extracting for10 minutes. The concentration range is 0.2~200μg/l.The detection limits of DCP,TCP,TeCP,and POP are 0.52, 0.03 ,0.02,and 0.03μg/l, respectively. We also applied this method to detect the CPs of real water sample and the results showed that the range of recoveries between 77.96% and 110 %. The proposed method provided a simple, fast, inexpensive and organic solventless procedure to collect CPs from complicated sample matrix.目錄 III 表目錄 V 圖目錄 VI 第一章 緒論 1 一、研究緣起與目的 1 二、研究架構與內容 2 三、氯酚化合物的特性及相關法規規定 4 四、氯酚化合物樣品前處理技術 10 (一) 液相-液相萃取法(Liquid-liquid extraction method，LLE) 10 (二) 液相-固相萃取法(Liquid-solid extraction method，LSE) 12 (三) 超臨界流體萃取(Supercritical fluid extraction，SFE) 13 (四) 固相萃取法(Solid phase extraction，SPE) 14 (五) 吸附-熱脫附法(Adsorption/thermal desorption，ATD) 17 (六) 固相萃取管柱-熱脫附法(Solid-phase extraction- thermal desorption，SPE-TD) 17 (七) 頂空間法(Headspace method) 18 (八) 固相微萃取法(Solid phase microextraion，SPME) 18 (九) 液相微萃取(Liquid-phase microextraction，LPME) 25 五、冷凍濃縮 37 第二章 試驗材料與研究方法 41 一、實驗藥品、器材與儀器設備 41 (一) 藥品 41 (二) 器材及儀器設備 42 (三) 玻璃器皿的矽烷化 43 (四) 藥品配製 43 二、液相微萃取的部分裝置之建立及操作 47 三、實驗步驟及條件探討 50 第三章 結果與討論 54 一、氣相層析與分離管柱之選擇 54 二、前處理方法之參數探討 56 (一) 萃取溶劑之選擇 56 (二) 冷凍結冰溫度的探討 59 (三) 萃取時間的探討 61 (四) 萃取液pH選擇的探討 62 (五) 鹽類添加的影響 63 三、分析方法評估 64 (一) 以直接進樣經 GC/ECD分析 64 (二) 以結晶濃縮/液相微萃取經GC/ECD分析 64 (三) 以直接進樣之分析CPs的精密度 66 (四) 以結晶濃縮/液相微萃取分析CPs的精密度 67 四、濃縮倍率及萃取百分率 68 (一) 以結晶濃縮/液相微萃取分析水中CPs之濃縮倍率 68 (二) 以結晶濃縮/液相微萃取分析水中CPs之萃取百分率 68 五、真實樣品的測定及回收率 69 (一) 真實樣品之採集 69 (二) 真實樣品CPs的檢驗 69 (三) 真實樣品回收率 69 六、直接浸入及結晶濃縮/液相微萃取法之比較 73 第四章 結論 74 第五章 參考文獻 7

A Sense of Community or Networked Individualism?

"This is a submission to the 3rd Annual Social Informatics SIG Research Symposium: The Social Web, Social Computing and the Social Analysis of Computing" This paper follows Wellmanâ s (2002) typology and aims at identifying new module of virtual communities. How does sense of community that used to mark virtual community differ from the concept of networked individualism? Who are those with high sense of community and/or networked individualism? Does the type of networked individualism supplant or supplement sense of community in community identity building? This case study indicated networked individualism did not supplant sense of community. In the contrary, they coexist in virtual community. Web 2.0 related social community has gradually gained its popularity in nowadays, this study implies that accessibility of these kinds of community resources is no more depends on sense of belonging and community consensus, in alternative, building instrumental networks, maintaining autonomous relationship with certain community members and shifting roles across networks become the key to mobilize network resources