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In order to achieve prevention and control of air pollution through energy consumption adjustment in advance, the paper proposes an Fuzzy Cognitive Map (FCM) of various energy resources affecting air quality, an incremental prediction algorithm of FCM and gradient descending method used to learn the FCM based on the small sample data on various energy consumptions and concentration of air pollutants. The FCM as an interpretable prediction method not only can predict future air quality more accurately, but also can analyze and interpret the affecting of various energy types on the future air quality. As the time delay of various energy consumptions affecting concentration of air pollutants, the quantitative time sequence influencing relationships (causality) in the FCM is mined directly from these data, and the air quality affected by various types of energy consumptions is predicted based on the FCM. Accordingly, the energy types affecting air pollution can be obtained for prior decision of energy consumption structure adjustment. The experimental results in Beijing-Tianjin-Hebei show that the FCM modeling is better than Support Vector Regression (SVR), Linear Regression (LR), Principal Component Analysis (PCA)-based forecasting, Convolutional Neural Networks (CNN) and Long-Short Term Memory (LSTM) methods in predicting air quality affected by energy resources, meanwhile according to the interpretable prediction results of the FCM, we obtain some interesting results and suggestions on energy consumption types in Beijing-Tianjin-Hebei regions in advance.

Purpose Mutations in hereditary breast cancer genes play an important role in the risk for cancer. Methods Cancer susceptibility genes were sequenced in 664 unselected breast cancer cases from Guatemala. Variants were annotated with ClinVar and VarSome. Results A total of 73 out of 664 subjects (11%) had a pathogenic variant in a high or moderate penetrance gene. The most frequently mutated genes were BRCA1 (37/664, 5.6%) followed by BRCA2 (15/664, 2.3%), PALB2 (5/664, 0.8%), and TP53 (5/664, 0.8%). Pathogenic variants were also detected in the moderate penetrance genes ATM, BARD1, CHEK2, and MSH6. The high ratio of BRCA1/BRCA2 mutations is due to two potential founder mutations: BRCA1 c.212 + 1G > A splice mutation (15 cases) and BRCA1 c.799delT (9 cases). Cases with pathogenic mutations had a significantly earlier age at diagnosis (45 vs 51 years, P P = 0.038) or breast cancer (33% vs 15%, P Conclusions Hereditary breast cancer mutations were observed among Guatemalan women, and these women are more likely to have early age at diagnosis and family history of cancer. These data suggest the use of genetic testing in breast cancer patients and those at high risk as part of a strategy to reduce breast cancer mortality in Guatemala.

Plesiomonas shigelloides, a member of the family Vibrionaceae, is a gram-negative, rod-shaped, facultative anaerobic bacterium with flagella. P. shigelloides has been isolated from such sources as freshwater, surface water, and many wild and domestic animals. P. shigelloides contains 102 Oantigens and 51 H-antigens. The diversity of O-antigen gene clusters is relatively poorly understood. In addition to O1 and O17 reported by other laboratories, and the 12 O serogroups (O2, O10, O12, O23, O25, O26, O32, O33, O34, O66, O75, and O76) reported previously by us, in the present study, nine new P. shigelloides serogroups (O8, O17, O18, O37, O38, O39, O44, O45, and O61) were sequenced and annotated. The genes for the O-antigens of these nine groups are clustered together in the chromosome between rep and aqpZ. Only O38 possesses the wzm and wzt genes for the synthesis and translocation of O-antigens via the ATP-binding cassette (ABC) transporter pathway; the other eight use the Wzx/Wzy pathway. Phylogenetic analysis using wzx and wzy showed that both genes are diversified. Among the nine new P. shigelloides serogroups, eight use wzx/wzy genes as targets. In addition, we developed an O-antigen-specific PCR assay to detect these nine distinct serogroups with no cross reactions among them.

Vibrio cholerae is a waterborne bacterium responsible for worldwide outbreaks of acute and fatal cholera. Recently, small regulatory RNAs (sRNAs) have become increasingly recognized as important regulators of virulence gene expression in response to environmental signals. In this study, we determined that two-component system EnvZ/OmpR was required for intestinal colonization in V. cholerae O1 EI Tor strain E12382. Analysis of the characteristics of OmpR revealed a potential binding site in the intergenic region between vc1470 and vc1471, and qRT-PCR showed that expression of the intergenic region increased 5.3-fold in the small intestine compared to LB medium. Race and northern blot assays were performed and demonstrated a new sRNA, coaR (cholerae osmolarity and acidity related regulatory RNA). A ΔcoaR mutant showed a deficient colonization ability in small intestine with CI of 0.15. We identified a target of coaR, tcpI, a negative regulator of the major pilin subunit of TcpA. The ΔtcpI mutant has an increased colonization with CI of 3.16. The expression of coaR increased 2.8-fold and 3.3-fold under relative acidic and hypertonic condition. In summary, coaR was induced under the condition of high osmolarity and acid stress via EnvZ/OmpR and explained that tcpI relieves pH-mediated repression of toxin co-regulated pilus synthesis.

Background The relationship between body mass index (BMI) and postoperative mortality in patients who undergo coronary artery bypass graft (CABG) surgery plus valve replacement is uncertain. We aimed to investigate the association between body mass index (BMI) and postoperative mortality among patients who simultaneously underwent both CABG surgery plus valve replacement. Methods We retrospectively analyzed 1976 patients who underwent CABG surgery at our hospital between January 2017 and April 2021, including 202 patients who underwent valve replacement surgery during the same period. We analyzed the relationship between BMI and postoperative mortality. The relationship between BMI and postoperative mortality was assessed using smooth curve fitting and a Multiple logistic regression model. Results The results of smoothing curve fitting showed that BMI and postoperative mortality had a non-linear relationship, and the resulting curve exhibited a two-stage change and a breakpoint. Postoperative mortality is higher in patients that have a body mass index above 25 kg/m2 compared to patients having a body mass index between 18 and 25 kg/m2. Conclusions Our study found a non-linear relationship between BMI and postoperative mortality in patients undergoing CABG plus valve replacement after adjusting for potential confounders. The causal relationship between BMI and postoperative mortality still requires further investigations.

Plesiomonas shigelloides is widely associated with human diarrheal disease. Research on this pathogen has been hampered by the absence of an effective genetic manipulation system. In the present study, an efficient and precise conjugation transfer procedure, mediated by suicide vector pRE112 was used to overcome this limitation. The efficiency of generating double recombinants was average 74.3%, and the conjugation protocol may be applied to other P. shigelloides strains. We also identified that the SipD protein of P. shigelloides G5884 (serotype O45) is 65% similar to the SipD in Salmonella pathogenicity island 1 (SPI-1), which is a key element of the type III secretion system related to Salmonella invasion. A P. shigelloides sipD null mutant was generated via the conjugation system, using the suicide vector pRE112. The isogenic mutant strain lacking sipD showed a 50% reduction in its capacity to invade Caco-2 cells.

The hybrid energy transmission line (HETL) consist of the superconducting cable and liquid hydrogen passing pipe provides a new solution for the high maintenance cost of cable, the high power load and the shortage of the construction land in city. In order to research the feasibility and economy of constructing the HETL in the reserved zone of a gas insulated metal enclosed transmission line (GIL) pipe gallery of China, the technical characteristics of the GIL pipe gallery and the HETL is analyzed. Based on the measurement result of the construction cost of the GIL in the pipe gallery, the construction cost of the HETL is calculated. The results show that, it is feasible and economic to construct the HETL in the reserved zone considering the whole life cycle cost of the project, the pattern of multiple energy complementary can be realized.

BackgroundMutations in hereditary breast cancer genes play an important role in the risk for cancer, however, little is known of the type and frequency of mutations in Central American populations, including Guatemala.MethodsTwo separate panels of known cancer susceptibility genes were used to sequence blood DNA from 664 unselected breast cancer cases from two large hospitals in Guatemala. Variants were annotated with ClinVar and VarSome. Data from a structured questionnaire was used to compare mutation carriers of medium and high penetrance genes.ResultsA total of 73 out of 664 subjects (11%) had a variant classified as pathogenic in a gene with known high or medium penetrance for inherited breast cancer. The most frequently mutated genes were BRCA1 (37/664, 5.6%) followed by BRCA2 (15/664, 2.3%), PALB2 (5/664, 0.8%) and TP53 (5/664, 0.8%). Pathogenic variants were also detected in the moderate penetrance genes ATM, BARD1, CHEK2, and MSH6, and rare pathogenic variants detected in the low penetrance genes AXIN2, FH, MLH1, MSH2, MUTYH, NF1, and SDHB. The high ratio of BRCA1/BRCA2 mutations is due to the presence of two potential founder mutations, BRCA1 c.212+1G>A splice mutation (15 cases) and BRCA1 c.799delT (9 cases). Compared to all others, cases with pathogenic mutations had a significantly earlier age at diagnosis (45 vs 51 years, PConclusionsGuatemalan women have rates of hereditary breast cancer mutations similar to other populations, and these women are more likely to have early age at diagnosis and family history. This data supports the use of genetic testing in breast cancer patients and those at high risk as part of a strategy to reduce breast cancer mortality in Guatemala.

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Steam condensation accompanying with air is an important thermal-hydraulic phenomenon in reactor containment. Condensation outside tubes is an important method to remove heat out of the containment under an accident. Most of the previous studies have been conducted on single tube and vertical plates, where the findings may not reflect the heat transfer in tube bundle well. The experimental studies were firstly carried out based on 3 × 3 tube bundle with diameters of 12–19 mm and inclination angles of 0–90° in the parameter range of pressure 0.2–1.6 MPa, air mass fraction of 12.1–75.2% and wall subcooling of 28.3–114.1℃. The results indicate that the effect of diameter and inclination angle in the tube bundle varies significantly in different pressure ranges. When the pressure is less than 0.8 MPa, the condensation heat transfer coefficient (CHTC) generally increases with decreasing tube diameter and inclination angle. The CHTC of the heat transfer tube with a tube diameter of 12 mm and an inclination angle of 0° increased by a maximum of 29% compared to that of the heat transfer tube with a tube diameter of 19 mm and an inclination angle of 90°. When the pressure is 0.8–1.6 MPa, the overall CHTC decreases as the diameter of the tube decreases, and the maximum reduction is about 20%. It decreases first and then increases with the decrease of the inclination angle, and the CHTC is the smallest when the inclination angle is about 60°.

Capsular polysaccharides (CPSs), or K-antigens, are the major surface antigens of Escherichia coli. More than 80 serologically unique K-antigens are classified into 4 groups (Groups 1–4) of capsules. Groups 1 and 4 contain the Wzy-dependent polymerization pathway and the gene clusters are in the order galF to gnd; Groups 2 and 3 contain the ABC-transporter-dependent pathway and the gene clusters consist of 3 regions, regions 1, 2 and 3. Little is known about the variations among the gene clusters. In this study, 9 serotypes of K-antigen gene clusters (K2ab, K11, K20, K24, K38, K84, K92, K96, and K102) were sequenced and correlated with their CPS chemical structures. On the basis of sequence data, a K-antigen-specific suspension array that detects 10 distinct CPSs, including the above 9 CPSs plus K30, was developed. This is the first report to catalog the genetic features of E. coli K-antigen variations and to develop a suspension array for their molecular typing. The method has a number of advantages over traditional bacteriophage and serum agglutination methods and lays the foundation for straightforward identification and detection of additional K-antigens in the future.

Mutations in hereditary breast cancer genes play an important role in the risk for cancer. Cancer susceptibility genes were sequenced in 664 unselected breast cancer cases from Guatemala. Variants were annotated with ClinVar and VarSome. A total of 73 out of 664 subjects (11%) had a pathogenic variant in a high or moderate penetrance gene. The most frequently mutated genes were BRCA1 (37/664, 5.6%) followed by BRCA2 (15/664, 2.3%), PALB2 (5/664, 0.8%), and TP53 (5/664, 0.8%). Pathogenic variants were also detected in the moderate penetrance genes ATM, BARD1, CHEK2, and MSH6. The high ratio of BRCA1/BRCA2 mutations is due to two potential founder mutations: BRCA1 c.212 + 1G > A splice mutation (15 cases) and BRCA1 c.799delT (9 cases). Cases with pathogenic mutations had a significantly earlier age at diagnosis (45 vs 51 years, P

Under severe accident conditions of a pressurized water reactor, hydrogen will be released into the containment, forming a mixture of steam-air-hydrogen, and then transported to the surroundings. This process can be coupled with complex mass transfer behavior caused by wall condensation. Under the coupling effect of condensation and buoyancy introduced by hydrogen, the mixture gas will form different types of transport behaviors. This will be closely related to the stratification and flammability risk of high-concentration hydrogen. To quantitatively determine these phenomena and assess the potential causing reasons, experiments were performed with helium instead of hydrogen based on the COAST (condensation and species transport) facility. The tests cover a broad parameter range with steam concentrations of 8.4– 89%, helium concentrations of 10– 66% (XHe/XNon), and pressures of 0.4– 1.3 MPa. The phenomena of steam condensation induced component separation were firstly confirmed in the tests, and the component concentration threshold was clarified at XHe/XNon = 50%. The three flow patterns of steam-air- helium mixture gas was identified by Shapiro-Moffette ternary diagram. Moreover, the temperature inverse stratification caused by the high-concentration helium-air layer was discovered in the experiments, and its influence on heat transfer was clarified.

Steam-air condensation is one of the important physical phenomena after reactor accidents, which has direct impacts on the discharge of containment residual heat after the accident. Previously, many researchers have proposed experimental correlations for condensation of non-condensable gas, which include the influence of pressure, concentration, and wall subcooling. However, there are relatively few studies on the influence of tube diameter and inclination angle. In order to investigate the heat transfer characteristics of the condenser at different tube diameters (19 mm, 15 mm, 12 mm) and inclination angles (0 ~ 90°), experiments were carried out in the pressure range of 0.15 ~ 1.6 MPa, air mass fraction of 14 ~ 87%, and wall subcooling of 28 ~ 122 °C. It shows that the condensation heat transfer coefficient (HTC) increases with the decrease of the tube diameter and inclination angle. The condensation HTC with a tube diameter of 12 mm and an inclination angle of 0°(Horizontally) is around 32 ~ 38% larger than that of the heat transfer tube with a tube diameter of 19 mm and an inclination angle of 90°(Vertically). Based on a total of 2276 data points from the present work and related experiments, an experimental correlation containing the effect of tube diameter and inclination angle is proposed, and its deviation is within ± 15% with 95% confidence.

Vibrio cholerae, the agent of severe diarrheal disease cholera, is known to form biofilm to persist in the environmental and the host,s intestines. The bacteria execute a complex regulatory pathway producing virulence factors that allow colonization and cause disease in response to environmental signals in the intestine, including low oxygen-limited condition. VpsR and VpsT are primary regulators of the biofilm formation-regulatory network. In this study, we determined that anaerobic induction enhanced biofilm formation via the two component system, ArcB/A, which functions as a positive regulator of toxT expression. The biofilm formation has reduced approximately 2.4-fold in the ΔarcA mutant compared to the wild type in anaerobic condition. Chip-qPCR and EMSA assays confirmed that ArcA can bind directly to the vpsT promoter and then activates the expression of biofilm formation related genes, vpsA-K and vpsL-Q. Meanwhile, the ΔarcA mutant decreased the ability of colonization in intestine with CI (competition index) of 0.27 compared to wild type strain. These results suggest that ArcA links the expression of virulence and biofilm synthesis genes during anaerobic condition, and contributes to understand the complex relationship between biofilm formation and the intestinal signals during infection.

Hepatic steatosis is the beginning phase of nonalcoholic fatty liver disease, and hyperhomocysteinemia (HHcy) is a significant risk factor. Soluble epoxide hydrolase (sEH) hydrolyzes epoxyeicosatrienoic acids (EETs) and other epoxy fatty acids, attenuating their cardiovascular protective effects. However, the involvement of sEH in HHcy-induced hepatic steatosis is unknown. The current study aimed to explore the role of sEH in HHcy-induced lipid disorder. We fed 6-wk-old male mice a chow diet or 2% (wt/wt) high-metnionine diet for 8 wk to establish the HHcy model. A high level of homocysteine induced lipid accumulation in vivo and in vitro, which was concomitant with the increased activity and expression of sEH. Treatment with a highly selective specific sEH inhibitor (0.8 mg·kg−1·day−1 for the animal model and 1 μM for cells) prevented HHcy-induced lipid accumulation in vivo and in vitro. Inhibition of sEH activated the peroxisome proliferator-activated receptor-α (PPAR-α), as evidenced by elevated β-oxidation of fatty acids and the expression of PPAR-α target genes in HHcy-induced hepatic steatosis. In primary cultured hepatocytes, the effect of sEH inhibition on PPAR-α activation was further confirmed by a marked increase in PPAR-response element luciferase activity, which was reversed by knock down of PPAR-α. Of note, 11,12-EET ligand dependently activated PPAR-α. Thus increased sEH activity is a key determinant in the pathogenesis of HHcy-induced hepatic steatosis, and sEH inhibition could be an effective treatment for HHcy-induced hepatic steatosis. NEW & NOTEWORTHY In the current study, we demonstrated that upregulation of soluble epoxide hydrolase (sEH) is involved in the hyperhomocysteinemia (HHcy)-caused hepatic steatosis in an HHcy mouse model and in murine primary hepatocytes. Improving hepatic steatosis in HHcy mice by pharmacological inhibition of sEH to activate peroxisome proliferator-activated receptor-α was ligand dependent, and sEH could be a potential therapeutic target for the treatment of nonalcoholic fatty liver disease.

Background Currently, over 20 genes have been defined that can confer susceptibility for high-risk breast cancer. Although research has proved the utility of multiple-gene sequencing in the assessment of breast cancer risk, there is little data from China patients. Here, we use a multiple-gene sequencing panel to identify the variant spectrum in Chinese high-risk breast cancer subjects. Findings A total of 829 Chinese high-risk breast cancer patients participated in the research. The coding regions of 115 hereditary cancer susceptibility genes were captured and sequenced using a next generation sequencing platform from Complete Genomics and Illumina. Single Nucleotide Polymorphism and small Insertion/deletion variants were defined and analyzed. We developed a semi-automatic interpretation pipeline which enables accurate variants classification. In total, 193 pathogenic variants were identified in 45 genes from 177 patients. The pathogenic variant carrier rate is 21.4%: with 10.5% patients carrying a BRCA1 or BRCA2 mutation only, 10.0% of patients carried non-BRCA gene mutations only, while 1.0% of patients carried both a BRCA1/2 and a non-BRCA gene mutation. Variants of uncertain significance (VUS) totaling 2632 were identified in 115 genes from 787 of 829 patients: 82.5% patients carried more than one VUS, and only 5.1% patients did not carry any VUS. Families carrying pathogenic variants were tracked and adenoma was founded in three of them. Conclusions Our data provide a comprehensive analysis of potential susceptibility variations of high-risk for breast cancer in a Chinese population. This data will be useful for the comparison of the susceptibility variation spectrum between different populations and to discover potential pathogenic variants to improve the prevention and treatment of high-risk breast cancer.

Steam condensation with existence of air is an important thermal hydraulic phenomenon in reactor containment. Previous investigations mostly focused on the surfaces of plates or tube bundles which are in parallel with the gas flow direction, and discussions on heat transfer surfaces with various inclination angles were merely restricted to plates. In addition, there is limited information about the condensation promotion effect caused by enlarged gas flow velocity at different tube inclination angles. To investigate the coupling effects of tube inclination and flow velocity, numerical simulations were carried on a 3 × 3 tube bundle. The local thermohydraulic profiles and heat transfer mechanism of steam condensation were analyzed carefully. The results indicate that the increase of inclination angle and flow velocity can dramatically promote condensation heat transfer. At the velocity of 0.3 m/s, the condensation heat transfer enhanced 327.8% as the tube bundle orientation changes from vertical to horizontal. At the inclination angle of 0°, the condensation heat transfer increased 223.2% as flow velocity increased from 0.3 m/s to 3 m/s. The inhibition effect and stack effect in tube bundle varied by the tube inclination and flow velocity.

Vibrio cholerae is a natural inhabitant of aquatic environments and causes the epidemic diarrheal disease known as cholera. Fatty acid metabolism is closely related to the pathogenicity of V. cholerae. The TetR family transcriptional repressor PsrA regulates the β-oxidation pathway in Pseudomonas aeruginosa; however, little is known about its regulation in V. cholerae. In this study, qRT-PCR revealed that the expression of vc1741 (psrA) increased 40-fold in the small intestines of infant mice compared with that grown in LB medium. The Δvc1741 mutant showed a significant defected in the ability to colonize the small intestines of infant mice with a competitive index (CI) of 0.53. EMSAs indicated that VC1741 could directly bind to the promoter regions of vc1741-fadE1, fadBA, and fadIJ operons, and these bindings were reversed upon addition of the long-chain fatty acid (LCFA), oleic acid. The expression levels of the fadB, fadA, fadI, and fadJ genes were all elevated by approximately 2-fold in the Δvc1741 mutant strain compared with that in the wild-type strain in LB medium, indicating that VC1741 is a repressor for these genes involved in fatty acid degradation. Moreover, ΔfadBA, ΔfadB, and ΔfadA isogenic mutants showed defective abilities to colonize the small intestines of infant mice, with CI values of 0.64, 0.73, and 0.74, respectively. These data provided a mechanistic model in which LCFAs affect the expression of VC1741 to control fatty acid degradation and virulence in V. cholerae.

Logistics is called “the source of the third profit”, and it has attracted more and more attention from people, and it has increasingly become the basic industry of the national economy. Distribution is a special and comprehensive form of activity in the logistics system, which is a close combination of logistics and business flow. Distribution is the process of allocating goods at the distribution center or other logistics nodes according to the requirements of the customer and handing them to the customer in the most reasonable way. After the economic work conference of the 18th National Congress of the Communist Party of China, the government and enterprises put green and low carbon in a more important position, and industries such as urban construction and traditional manufacturing need to think about how to become greener, especially for the logistics and transportation industry. Based on this research background, the paper developed an intelligent vehicle scheduling system. Based on the summarization of a large number of applications at home and abroad, from the two aspects of the vehicle routing problem model and solution algorithm, the domestic and foreign research status of the vehicle routing problem is deeply analysed. According to different factors, the vehicle routing problem is based on the basic model and the derivative model. To classify and solve the current research hot issues-open vehicle routing problem and dynamic network vehicle routing problem. The system includes vehicle scheduling, management of carrier bills, electronic map display, basic information maintenance and other functions.

The absence of interpretation guidelines and limited data on BRCA1/2 mutations in the Chinese population have impeded the detection of BRCA variants based on next-generation sequencing (NGS) in China. This study was performed to establish a reference system for performance evaluation of BRCA genetic testing and variant interpretation, which includes interpretation rules, reference materials (RMs), and a reference database (RD). BRCA1/2 mutations identified in cell lines and clinical cases were selected to establish RMs. All mutations were detected by NGS and validated by Sanger sequencing. Variant call format files and standard variant data sets were collected and annotated to build the RD. Participant laboratories were invited to validate this reference system. Interpretation rules for BRCA variants in the Chinese population were generated as a standard for BRCA variant interpretation. Mutational analysis demonstrated that BRCA2 mutations (55%) were more common than BRCA1 mutations (45%) in Chinese patients. Eliminating duplicates from 19,886 variants, the RD contained 750 unique BRCA mutations. Most BRCA1/2 mutations in the reference system were pathogenic or likely pathogenic (RMs, 77.5%; RD, 57%). In total, 91 novel pathogenic/likely pathogenic variants were identified in the RD. The reference system can contribute to NGS performance and high-quality interpretation to facilitate clinical decision making. It could also accelerate the development and application of BRCA mutation detection technologies in China.

Among the 50 species and 70 serogroups of Legionella identified, Legionella pneumophila, comprising three subsp. (subsp. pneumophila, subsp. fraseri, and subsp. pasculleii), is recognized as the major cause of epidemic legionellosis. Rapid and reliable assays to identify pathogenic Legionella spp., and the three L. pneumophila subsp. in particular, are in great demand. In this study, we analyzed the gyrB genes of eleven Legionella spp. and subsp., comprising L. anisa, L. bozemanii, L. dumoffii, L. feeleii, L. gormanii, L. longbeachae, L. micdadei, L. waltersii, L. pneumophila subsp. pneumophila, L. pneumophila subsp. fraseri, and L. pneumophila subsp. pasculleii. We developed a rapid oligonucleotide microarray detection technique to identify accurately these common pathogenic Legionella spp. and L. pneumophila subsp. To detect multiple Legionella species with high specificity, 31 reproducible probes were designed in the array. Sixty-one strains were analyzed in total, including 37 target pathogens and 24 non-target bacterial species used to validate the microarray. The sensitivity of the detection was 1.0 ng using genomic DNA of three Legionella spp., L. anisa, L. dumoffii, and L. waltersii, or 13 CFU/100 mL using the cultured L. pneumophila subsp. pneumophila. Eight isolated strains were tested using the microarray with 100% accuracy. The data indicated that the technique is an efficient method to diagnose and detect Legionella spp. and subsp. in basic microbiology, clinical diagnosis, epidemiological surveillance, and food safety applications. In addition, a phylogenetic study based on the gyrB gene revealed the genetic relationship among the different Legionella spp. and subsp.

Vibrio cholerae has caused seven cholera pandemics since 1817, imposing terror on much of the world, but bacterial strains are currently only available for the sixth and seventh pandemics. The El Tor biotype seventh pandemic began in 1961 in Indonesia, but did not originate directly from the classical biotype sixth-pandemic strain. Previous studies focused mainly on the spread of the seventh pandemic after 1970. Here, we analyze in unprecedented detail the origin, evolution, and transition to pandemicity of the seventh-pandemic strain. We used high-resolution comparative genomic analysis of strains collected from 1930 to 1964, covering the evolution from the first available El Tor biotype strain to the start of the seventh pandemic. We define six stages leading to the pandemic strain and reveal all key events. The seventh pandemic originated from a nonpathogenic strain in the Middle East, first observed in 1897. It subsequently underwent explosive diversification, including the spawning of the pandemic lineage. This rapid diversification suggests that, when first observed, the strain had only recently arrived in the Middle East, possibly from the Asian homeland of cholera. The lineage migrated to Makassar, Indonesia, where it gained the important virulence-associated elements Vibrio seventh pandemic island I (VSP-I), VSP-II, and El Tor type cholera toxin prophage by 1954, and it then became pandemic in 1961 after only 12 additional mutations. Our data indicate that specific niches in the Middle East and Makassar were important in generating the pandemic strain by providing gene sources and the driving forces for genetic events.