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Wetland plants, including rice (Oryza spp.), have developed multiple functional adaptive traits to survive soil flooding, partial submergence or even complete submergence. In waterlogged soils and under water, diffusion of O2 and CO2 is extremely slow with severe impacts on photosynthesis and respiration. As a response to shallow floods or rising floodwater, several rice varieties, including deepwater rice, elongate their stems to keep their leaves above the water surface so that photosynthesis can occur unhindered during partial submergence. In stark contrast, some other varieties hardly elongate even if they become completely submerged. Instead, their metabolism is reduced to an absolute minimum so that carbohydrates are conserved enabling fast regrowth once the floodwater recedes. This review focuses on the fascinating functional adaptive traits conferring tolerance to soil flooding, partial or complete submergence. We provide a general analysis of these traits focusing on molecular, anatomical and morphological, physiological and ecological levels. Some of these key traits have already been introgressed into modern highyielding genotypes improving flood tolerance of several cultivars used by millions of farmers in Asia. However, with the ongoing changes in climate, we propose that even more emphasis should be placed on improving flood tolerance of rice by breeding for rice that can tolerate longer periods of complete submergence or stagnant flooding. Such tolerance could be achieved via additional tissues; i.e. aquatic adventitious roots relevant during partial submergence, and leaves with higher underwater photosynthesis caused by a longer gas film retention time. [ABSTRACT FROM AUTHOR]

Chinese cabbage is an important vegetable in Asia, and high-yielding hybrids are needed to cope with the growing demand. A comparative transcriptome profiling was conducted to reveal the differentially expressed genes (DEGs) associated with heterosis in two hybrids relative to their parents. Our data suggests that heterosis is underlined by a significant upregulation of gene expression. High expression of DEGs in glycolysis and photosynthesis pathways in hybrids depicted their relation with growth and hybrid vigor. Besides, DEGs related to auxin, abscisic acid, ethylene and gibberellin were identified, implying that these hormones may boost the mechanisms of growth and developmental processes in the hybrids. Furthermore, transcription factors, including bHLH, ERF, MYB and WRKY were predicted to regulate downstream genes linked to hybrid vigor. Collectively, the present study will be helpful for a better understanding of the regulation mechanisms of heterosis to aid cabbage yield improvement. • Transcriptional mechanisms of heterosis in Chinese cabbage was studied. • Heterosis is underlined by a significant upregulation of gene expression. • Heterosis is mainly associated with non-additive expression. • Glycolysis and photosynthesis pathways were altered in hybrids. • Phytohormones related genes play crucial role in heterosis. [ABSTRACT FROM AUTHOR]

Background: Ever since coronavirus disease 2019 (COVID-19) emerged in Wuhan, China, in December 2019, it has had a devastating effect on the world through exponential case growth and death tolls in at least 146 countries. Rapid response and timely modifications in the emergency department (ED) for infection control are paramount to maintaining basic medical services and preventing the spread of COVID-19. This study presents the unique measure of combining a fever screening station (FSS) and graded approach to isolation and testing in a Taiwanese medical center. Methods: An FSS was immediately set up outside the ED on January 27, 2019. A graded approach was adopted to stratify patients into "high risk," "intermediate risk," and "undetermined risk" for both isolation and testing. Results: A total of 3755 patients were screened at the FSS, with 80.3% visiting the ED from home, 70.9% having no travel history, 21.4% having traveled to Asia, and 10.0% of TVGH staff. Further, 54.9% had fever, 35.5% had respiratory symptoms, 3.2% had gastrointestinal symptoms, 0.6% experienced loss of smell, and 3.1% had no symptoms; 81.3% were discharged, 18.6% admitted, and 0.1% died. About 1.9% were admitted to the intensive care unit, 10.3% to the general ward, and 6.4% were isolated. Two patients tested positive for COVID-19 (0.1%) and 127 (3.4%) tested positive for atypical infection; 1471 patients were tested for COVID-19; 583 were stratified as high-risk, 781 as intermediate-risk, and 107 as undetermined-risk patients. Conclusion: Rapid response for infection control is a paramount in the ED to confront the COVID-19 outbreak. The FFS helped divide the flow of high- and intermediate-risk patients; it also decreased the ED workload during a surge of febrile patients. A graded approach to testing uses risk stratification to prevent nosocomial infection of asymptomatic patients. A graded approach to isolation enables efficient allocation of scarce medical resources according to risk stratification. [ABSTRACT FROM AUTHOR]

Cerasus serrulata (Rosaceae) is an important flowering cherry resource which is valuable for developing new cultivars of flowering cherries. It is broadly distributed and possesses abundant variations. In this study, phylogeographic analysis was conducted to reveal the evolutionary history to better understand the genetic diversity and genetic structure of C. serrulata so as to provide more accurate molecular insights into better conservation and utilization of the germplasm resources. A total of 327 individuals from 18 wild populations were collected. Three chloroplast DNA (cpDNA) fragments (matK, trnD‐E, and trnS‐G) and the nuclear internal transcribed spacer (ITS) were utilized. The results showed a high genetic diversity at both species level and population level of C. serrulata. High genetic differentiation and the existence of the phylogeographic structure were detected. No significant expansion events were discovered. Two geographic lineages were inferred. One was confined to the Qinling Mountains and the Taihang Mountains. The other was from the Wuling Mountains to the Jiangnan Hilly Regions and then went northeast to the coast of Asia. In addition, some taxonomic treatments of the C. serrulata complex are discussed and reconsidered. Conservation and utilization strategies of wild C. serrulata germplasm resources were recommended. [ABSTRACT FROM AUTHOR]

The dynamic process of ocean-continent subduction depends on not only the properties of the subducting oceanic plate, but also the characteristics and state of the overriding continental plate. Numerical models conducted to date have mostly focused on the oceanic lithosphere in this regard; research on the properties of overriding continental lithosphere remains relatively limited, especially the influence of its thermal state on subduction dynamics. Here we explored the performance of continental lithosphere with different thermal states during the subduction process using two-dimensional thermal-mechanical modeling and systematically investigated the effects of the thermal state of overriding continental plate, the age of subducting oceanic plate, and relative convergence rate on subduction dynamics. Modeling results show that: (1) When the geothermal gradient of continental crust is low (between 10 and 15 °C km−1), the oceanic plate first subducts at a low angle. As subduction continues, the slab dip gradually increases and the slab begins to retreat rapidly driven by its negative buoyancy, opening an ocean basin ranging from 600 to 1100 km in width. This leads to the decoupling between the overriding continental plate and oceanic plate. As the trench retreat continues, the horizontal deviatoric stress inside the overriding continental crust alternates between being positive and negative in a local area. Thinning of the overriding lithosphere mainly occurs at the region adjacent to the subduction zone, where the surface experiences significant subsidence. (2) When the geothermal gradient of continental crust is higher (greater than 15 °C km−1), oceanic plate retreat causes the overriding continental plate to be strongly stretched. In this case, the trench retreat distance decreases and the width of the ocean basin also reduces by between 100 and 1000 km. The horizontal deviatoric stress inside the whole overriding continental crust first manifests as compression and then changes into extension, which causes the surface to first uplift and then slowly subside. (3) Increasing the age of oceanic lithosphere accelerates trench retreat and promotes overriding plate thinning. (4) An advancing overriding continental plate slows down trench retreat. In cases where the geothermal gradient of continental crust is greater than 17.5 °C km−1, the hot continental crust experiences gravitational collapse and is overthrusted onto oceanic lithosphere, resulting in slow trench retreat. We analyzed the subduction process of the western Paleo-Pacific Plate in the Early Cretaceous based on our modeling results and discussed its possible control on the tectonic evolution of the rift basins in east Asia. We suggest that the development of a wide rift basin system on the Amurian Superterrane in the Early Cretaceous was likely related to slow trench retreat and the collapse of the hot crust, and the formation of a series of passive rift basins in the North China Craton was likely caused by the relatively cold thermal state of the lithosphere and the rapid retreat of the Paleo-Pacific Plate. [ABSTRACT FROM AUTHOR]

Background: Human coexistence with other animals can result in both intentional and unintentional contact with a variety of mammalian and non-mammalian species. International travellers are at risk for such encounters; travellers risk injury, infection and possibly death from domestic and wild animal bites, scratches, licks and other exposures. The aim of the present analysis was to understand the diversity and distribution of animal-related exposures among international travellers.Methods: Data from January 2007 through December 2018 from the GeoSentinel Surveillance Network were reviewed. Records were included if the exposure was non-migration travel with a diagnosis of an animal (dog, cat, monkey, snake or other) bite or other exposure (non-bite); records were excluded if the region of exposure was not ascertainable or if another, unrelated acute diagnosis was reported.Results: A total of 6470 animal exposures (bite or non-bite) were included. The majority (71%) occurred in Asia. Travellers to 167 countries had at least one report of an animal bite or non-bite exposure. The majority (76%) involved dogs, monkeys and cats, although a wide range of wild and domestic species were involved. Almost two-thirds (62.6%) of 4395 travellers with information available did not report a pretravel consultation with a healthcare provider.Conclusions: Minimizing bites and other animal exposures requires education (particularly during pretravel consultations) and behavioral modification. These should be supplemented by the use of pre-exposure rabies vaccination for travellers to high-risk countries (especially to those with limited access to rabies immunoglobulin), as well as encouragement of timely (in-country) post-exposure prophylaxis for rabies and Macacine alphaherpesvirus 1 (herpesvirus B) when warranted. [ABSTRACT FROM AUTHOR]

Background: Japanese encephalitis (JE) and rabies are serious vaccine preventable diseases which are an important consideration for travelers to Asia.Methods: Five Boston-area travel clinics collected demographic data, trip information, and interventions for travelers to Asia seen at pre-travel consultations from March 1, 2008, through July 31, 2010. We evaluated travelers for proportion vaccinated for JE and rabies, those traveling for >1 month, and whether travelers had adequate time to complete the JE series (clinic visit ≥28 days before departure) and rabies pre-exposure prophylaxis (clinic visit ≥21 days before departure).Results: Among 15,440 travelers from five Boston Area Travel Medicine Network travel clinics, Asia was the most common destination region, visited by 5,582 (36%) of travelers. Among these travelers, 4,810 (86%) planned to travel to only one Asian subregion. Median trip duration was 17 days, with more than 20% traveling for >1 month. The most common destinations were South (41%), Southeast (26%), and East (23%) Asia. Of those traveling to South, Southeast, or East Asia, over one-third with trips >1 month had insufficient time to complete a series for either JE or rabies vaccine. Overall, only 10% of travelers were vaccinated (past and pre-travel visit) for either JE or rabies, with lowest percentages among travelers visiting friends and relatives. Most travelers received advice on vector precautions (96%) and rabies prevention, which included avoiding animal contact, washing wounds, and obtaining appropriate post-exposure prophylaxis (88%).Conclusion: Given the insufficient time for completion and relatively low vaccination rates, greater awareness of earlier pre-travel consultations, at least 4-6 weeks before travel, and accurate risk assessment for travelers are important. Effective counseling about vector avoidance, rabies, and animal bite prevention and management remains critical. [ABSTRACT FROM AUTHOR]

Background: Enterovirus 71 (EV71) has caused several epidemics of hand, foot and mouth diseases (HFMD) in Asia and now is being recognized as an important neurotropic virus. Effective medications and prophylactic vaccine against EV71 infection are urgently needed. Based on the success of inactivated poliovirus vaccine, a prototype chemically inactivated EV71 vaccine candidate has been developed and currently in human phase 1 clinical trial. Principal Finding:In this report, we present the development of a serum-free cell-based EV71 vaccine. The optimization at each step of the manufacturing process was investigated, characterized and quantified. In the up-stream process development, different commercially available cell culture media either containing serum or serum-free was screened for cell growth and virus yield using the roller-bottle technology. VP-SFM serum-free medium was selected based on the Vero cell growth profile and EV71 virus production. After the up-stream processes (virus harvest, diafiltration and concentration), a combination of gel-filtration liquid chromatography and/or sucrose-gradient ultracentrifugation down-stream purification processes were investigated at a pilot scale of 40 liters each. Although the combination of chromatography and sucrose-gradient ultracentrifugation produced extremely pure EV71 infectious virus particles, the overall yield of vaccine was 7-10% as determined by a VP2-based quantitative ELISA. Using chromatography as the downstream purification, the virus yield was 30-43%. To retain the integrity of virus neutralization epitopes and the stability of the vaccine product, the best virus inactivation was found to be 0.025% formalin-treatment at 37°C for 3 to 6 days. Furthermore, the formalin-inactivated virion vaccine candidate was found to be stable for .18 months at 4uC and a microgram of viral proteins formulated with alum adjuvant could induce strong virus-neutralizing antibody responses in mice, rats, rabbits, and non-human primates. Conclusion: These results provide valuable information supporting the current cell-based serum-free EV71 vaccine candidate going into human Phase I clinical trials. [ABSTRACT FROM AUTHOR]

The Cenozoic India-Asia collision reactivated several ancient thrust belts in the interior of the Asian continent, including the West and East Kunlun ranges in central Tibet, and the Tian Shan and Qilian Shan further north. Both basin sedimentary records and thermochronological data show that the uplift of the South Tian Shan and Qilian Shan at the north occurred earlier than that of the West and East Kunlun ranges at the south. Diachronous continental deformation and initiation of uplift during orogeny are contrary to the general notion that the stress transfer in response to the India-Asia collision should propagate sequentially from south to north. Here we systematically conducted 2D thermo-mechanical simulations to investigate possible factors for this diachronous deformation pattern. The results show that a hotter Tian Shan lithosphere, with Moho temperature >100 °C hotter than that of the proto-southern Asia, leads to an earlier and higher uplift of the Tian Shan. Additionally, a faster convergence rate of the India-Asia collision results in a more efficient transfer of boundary force into the upper plate's interior, giving rise to a larger amount of uplift in the Tian Shan. We conclude that intra-continental ranges with weaker lithosphere, such as the Tian Shan or Qilian Shan, uplift earlier than stronger regions, such as the West and East Kunlun ranges. Faster convergence rates amplify this situation. Our results imply that the unique diachronous growth of the Tibetan plateau arises from its complex pre-collisional history, which includes collided arc-continent terranes with hotter and weaker lithosphere that respond to the effects of far-field stress transfer. • Controls on intra-continent diachronous rise are investigated by numerical modeling. • Intra-continent thrust belts with weaker lithosphere uplift earlier. • Faster convergence rate at the boundary amplifies the diachronous rise situation. • Evolution of Tibetan plateau is controlled by the complex pre-collisional history. [ABSTRACT FROM AUTHOR]

The Paleogene sedimentary successions of the Tarim Basin of western China document a major regression of the proto-Paratethys Sea, significantly changing the land-sea distribution and thereby the palaeoclimatic conditions in Central Asia. However, a comprehensive reconstruction of the palaeogeographic evolution of the basin is lacking because only few exposures are known from the central part of the basin that is mostly covered by the Taklamakan Desert. Here, we reconstruct the main palaeoenvironmental changes following Eocene sea retreat by determining the sedimentological facies of 69 wells that are internally correlated by using seismic profiles and externally to published sections of the exposed southwestern and northern margins of the Tarim Basin. Two major depocentres existed in the Southwest Foredeep and the Kuqa Depression, separated from each other by the Bachu Uplift that was most likely not a particularly high terrain during the Paleogene. We confirm that a major transition from marine to continental-lacustrine sedimentation took place during the Eocene-Oligocene transition in the central parts of the Tarim Basin. We provide new palaeogeographic maps with Eocene and Oligocene facies distributions in the Tarim Basin, which will facilitate a better understanding of the sedimentary response to Paleogene sea-level change and tectonic events of the neighboring mountain ranges. Our reconstruction confirms that both tectonic and eustatic forcing played an active role in controlling the late Paleogene transgression-regression in the Tarim Basin. Provenance and palaeocurrent analyses, combined with sediment distribution patterns, indicate gradual growth and continuous uplift of the Tibetan Plateau following India–Asia collision in the early Paleogene. The demise of the Tarim Sea at ~41 Ma correlates with palaeoclimatic and environmental changes observed in several basin of central Asia. After sea retreat, the Tarim region progressively transformed into a large and shallow lake system that potentially persisted up to the (early) Oligocene. • Sedimentary facies of 69 drill holes from the Tarim Basin of SW China are analysed. • Palaeogeographic reconstructions are based on Eocene-Oligocene facies distribution. • Facies patterns indicate late Eocene tectonic activity of the Pamir and West Kunlun. • Early Bartonian sea retreating from Tarim relates in time to inner Asian aridification. • During the early Oligocene a large lake persisted in the Tarim Basin. [ABSTRACT FROM AUTHOR]

Background: Chikungunya is an important travel-related disease because of its rapid geographical expansion and potential for prolonged morbidity. Improved understanding of the epidemiology of travel-related chikungunya infections may influence prevention strategies including education and vaccination., Methods: We analysed data from travellers with confirmed or probable chikungunya reported to GeoSentinel sites from 2005 to 2020. Confirmed chikungunya was defined as a compatible clinical history plus either virus isolation, positive nucleic acid test or seroconversion/rising titre in paired sera. Probable chikungunya was defined as a compatible clinical history with a single positive serology result., Results: 1202 travellers (896 confirmed and 306 probable) with chikungunya were included. The median age was 43 years (range 0-91; interquartile range [IQR]: 31-55); 707 (58.8%) travellers were female. Most infections were acquired in the Caribbean (28.8%), Southeast Asia (22.8%), South Central Asia (14.2%) and South America (14.2%). The highest numbers of chikungunya cases reported to GeoSentinel were in 2014 (28.3%), 2015 (14.3%) and 2019 (11.9%). The most frequent reasons for travel were tourism (n = 592; 49.3%) and visiting friends or relatives (n = 334; 27.7%). The median time to presentation to a GeoSentinel site was 23 days (IQR: 7-52) after symptom onset. In travellers with confirmed chikungunya and no other reported illnesses, the most frequently reported symptoms included musculoskeletal symptoms (98.8%), fever/chills/sweats (68.7%) and dermatologic symptoms (35.5%). Among 917 travellers with information available, 296 (32.3%) had a pretravel consultation., Conclusions: Chikungunya was acquired by international travellers in almost 100 destinations globally. Vector precautions and vaccination where recommended should be integrated into pretravel visits for travellers going to areas with chikungunya or areas with the potential for transmission. Continued surveillance of travel-related chikungunya may help public health officials and clinicians limit the transmission of this potentially debilitating disease by defining regions where protective measures (e.g. pretravel vaccination) should be strongly considered., (© The Author(s) 2024. Published by Oxford University Press on behalf of International Society of Travel Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Consumers are often overlooked as key drivers of vegetation structure and ecosystem functioning in coastal wetlands. This oversight is particularly apparent in Asia, where much of the variation in coastal wetland plant growth and composition is attributed to physical stress gradients. To address this knowledge gap and quantify the relative importance of consumers in Asian coastal wetlands across temporal variation in environmental stress, we conducted a two-year experiment spanning relatively spring wet (2018) and spring dry (2019) years in which we manipulated the presence of the numerically dominant herbivorous crab, Helice tientsinensis, and evaluated its effects on Phragmites australis growth and structure in a Yellow River Delta salt marsh. In spring wetter 2018, Phragmites biomass and stem density were 75% and 34% higher in Crab Exclusion relative to Ambient Crab plots. In 2019 which experienced spring drought and elevated soil salinity, Phragmites biomass and stem density remained similarly high relative to 2018 in Crab Exclusion plots, but fell further, to only 16% and 39% of levels of 2018 observed in Ambient Crab plots. Phragmites' inflorescences density was also significantly reduced in Ambient Crab than Crab Exclusion plots in 2019. Together, these results highlight the significant role that crab herbivores can play in regulating Phragmites in Yellow River Delta salt marshes and suggest that the magnitude of their top-down control may be amplified, although in a non-additive manner, with spring drought stress in the region., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

This collaborative statement from the International Society for Holter and Noninvasive Electrocardiology/ Heart Rhythm Society/ European Heart Rhythm Association/ Asia Pacific Heart Rhythm Society describes the current status of mobile health ("mHealth") technologies in arrhythmia management. The range of digital medical tools and heart rhythm disorders that they may be applied to and clinical decisions that may be enabled are discussed. The facilitation of comorbidity and lifestyle management (increasingly recognized to play a role in heart rhythm disorders) and patient self-management are novel aspects of mHealth. The promises of predictive analytics but also operational challenges in embedding mHealth into routine clinical care are explored., (This article has been co-published with the permission of Annals of Noninvasive Electrocardiology, Cardiovascular Digital Health Journal, Circulation: Arrhythmia and Electrophysiology, European Heart Journal - Digital Health and Journal of Arrhythmia. All rights reserved. © 2021 The Authors. Annals of Noninvasive Electrocardiology published by Wiley Periodicals Inc. on behalf of the International Society for Holter and Noninvasive Electrocardiology / Cardiovascular Digital Health Journal published by Elsevier Inc. on behalf of the Heart Rhythm Society / Circulation: Arrhythmia and Electrophysiology published by Wolters Kluwer Health, Inc. on behalf of the American Heart Association, Inc. / European Heart Journal - Digital Health published by Oxford University Press on behalf of the European Society of Cardiology / Journal of Arrhythmia published by Wiley and Sons Australia Ltd on behalf of the Japanese Heart Rhythm Society and the Asia Pacific Heart Rhythm Society. This article is published under the Creative Commons CC-BY license, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. The articles are identical except for minor stylistic and spelling differences in keeping with each journal’s style. Either citation can be used when citing this article.)

Introduction: International travellers contribute to the rapid spread of Zika virus (ZIKV) and its sentinel identification globally. We describe ZIKV infections among international travellers seen at GeoSentinel sites with a focus on ZIKV acquired in the Americas and the Caribbean, describe countries of exposure and traveller characteristics, and assess ZIKV diagnostic testing by site., Methods: Records with an international travel-related diagnosis of confirmed or probable ZIKV from January 2012 through December 2019 reported to GeoSentinel with a recorded illness onset date were included to show reported cases over time. Records from March 2016 through December 2019 with an exposure region of the Americas or the Caribbean were included in the descriptive analysis. A survey was conducted to assess the availability, accessibility and utilization of ZIKV diagnostic tests at GeoSentinel sites., Results: GeoSentinel sites reported 525 ZIKV cases from 2012 through 2019. Between 2012 and 2014, eight cases were reported, and all were acquired in Asia or Oceania. After 2014, most cases were acquired in the Americas or the Caribbean, a large decline in ZIKV cases occurred in 2018-19.Between March 2016 and December 2019, 423 patients acquired ZIKV in the Americas or the Caribbean, peak reporting to these regions occurred in 2016 [330 cases (78%)]. The median age was 36 years (range: 3-92); 63% were female. The most frequent region of exposure was the Caribbean (60%). Thirteen travellers were pregnant during or after travel; one had a sexually acquired ZIKV infection. There was one case of fetal anomaly and two travellers with Guillain-Barré syndrome. GeoSentinel sites reported various challenges to diagnose ZIKV effectively., Conclusion: ZIKV should remain a consideration for travellers returning from areas with risk of ZIKV transmission. Travellers should discuss their travel plans with their healthcare providers to ensure ZIKV prevention measures are taken., (Published by Oxford University Press 2020.)

Background: Analysis of a large cohort of business travelers will help clinicians focus on frequent and serious illnesses. We aimed to describe travel-related health problems in business travelers., Methods: GeoSentinel Surveillance Network consists of 64 travel and tropical medicine clinics in 29 countries; descriptive analysis was performed on ill business travelers, defined as persons traveling for work, evaluated after international travel 1 January 1997 through 31 December 2014., Results: Among 12 203 business travelers seen 1997-2014 (14 045 eligible diagnoses), the majority (97%) were adults aged 20-64 years; most (74%) reported from Western Europe or North America; two-thirds were male. Most (86%) were outpatients. Fewer than half (45%) reported a pre-travel healthcare encounter. Frequent regions of exposure were sub-Saharan Africa (37%), Southeast Asia (15%) and South Central Asia (14%). The most frequent diagnoses were malaria (9%), acute unspecified diarrhea (8%), viral syndrome (6%), acute bacterial diarrhea (5%) and chronic diarrhea (4%). Species was reported for 973 (90%) of 1079 patients with malaria, predominantly Plasmodium falciparum acquired in sub-Saharan Africa. Of 584 (54%) with malaria chemoprophylaxis information, 92% took none or incomplete courses. Thirteen deaths were reported, over half of which were due to malaria; others succumbed to pneumonia, typhoid fever, rabies, melioidosis and pyogenic abscess., Conclusions: Diarrheal illness was a major cause of morbidity. Malaria contributed substantial morbidity and mortality, particularly among business travelers to sub-Saharan Africa. Underuse or non-use of chemoprophylaxis contributed to malaria cases. Deaths in business travelers could be reduced by improving adherence to malaria chemoprophylaxis and targeted vaccination for vaccine-preventable diseases. Pre-travel advice is indicated for business travelers and is currently under-utilized and needs improvement.

A large fraction of human genes are regulated by genetic variation near the transcribed sequence (cis-eQTL, expression quantitative trait locus), and many cis-eQTLs have implications for human disease. Less is known regarding the effects of genetic variation on expression of distant genes (trans-eQTLs) and their biological mechanisms. In this work, we use genome-wide data on SNPs and array-based expression measures from mononuclear cells obtained from a population-based cohort of 1,799 Bangladeshi individuals to characterize cis- and trans-eQTLs and determine if observed trans-eQTL associations are mediated by expression of transcripts in cis with the SNPs showing trans-association, using Sobel tests of mediation. We observed 434 independent trans-eQTL associations at a false-discovery rate of 0.05, and 189 of these trans-eQTLs were also cis-eQTLs (enrichment P<0.0001). Among these 189 trans-eQTL associations, 39 were significantly attenuated after adjusting for a cis-mediator based on Sobel P<10-5. We attempted to replicate 21 of these mediation signals in two European cohorts, and while only 7 trans-eQTL associations were present in one or both cohorts, 6 showed evidence of cis-mediation. Analyses of simulated data show that complete mediation will be observed as partial mediation in the presence of mediator measurement error or imperfect LD between measured and causal variants. Our data demonstrates that trans-associations can become significantly stronger or switch directions after adjusting for a potential mediator. Using simulated data, we demonstrate that this phenomenon is expected in the presence of strong cis-trans confounding and when the measured cis-transcript is correlated with the true (unmeasured) mediator. In conclusion, by applying mediation analysis to eQTL data, we show that a substantial fraction of observed trans-eQTL associations can be explained by cis-mediation. Future studies should focus on understanding the mechanisms underlying widespread cis-mediation and their relevance to disease biology, as well as using mediation analysis to improve eQTL discovery.

In this study, we identify a recombinant pb1 gene, a recombinant MP segment and a recombinant PA segment. The pb1 gene is recombined from two Eurasia swine H1N1 influenza virus lineages. It belongs to a H1N1 swine clade circulating in Europe and Asia from 1999 to 2009. The mosaic MP segment descends from H7 avian and H1N1 human virus lineages and pertains to a large human H1N1 virus family circulating in Asia, Europe and America from 1918 to 2007. The recombinant PA segment originated from two swine H1N1 lineages is found in a swine H1N1 group prevailing in Asia and Europe from 1999 to 2003. These results collectively falsify the hypothesis that influenza virus do not evolve by homologous recombination. Since recombination not only leads to virus genome diversity but also can alter its host adaptation and pathogenecity; the genetic mechanism should not be neglected in influenza virus surveillance., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Purpose of Review: Dengue and chikungunya are arboviruses that have caused major outbreaks and infected travelers, and both can be associated with fever and rash. We review the recent epidemiology of dengue and chikungunya infections and discuss their clinical presentations, diagnosis, treatment, and prevention. We highlight the findings in travelers., Recent Findings: Globally dengue is one of the most common infections associated with travel, and incidence has increased in the Americas in recent years, especially in Brazil. Chikungunya has caused dramatic outbreaks in the Indian Ocean islands since 2004, and has spread to south and south-east Asia. Dengue virus and chikungunya virus also possess the potential to cause autochthonous transmission in temperate regions of developed countries due to the presence of the vector mosquito, Aedes albopictus. Such an outbreak (chikungunya infection) did occur in 2007 in Italy. A mutation in chikungunya virus (A226V) appears to improve virus survival in Aedes albopictus and also increase its virulence., Summary: The findings assist in differentiating dengue and chikungunya from other acute febrile illnesses and from each other. The findings also illustrate potential outbreaks in nonendemic countries, important toward developing control and prevention strategies.