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161.
Thai KT Nishiura H Hoang PL Tran NT Phan GT Le HQ Tran BQ Nguyen NV de Vries PJ 《PLoS neglected tropical diseases》2011,5(6):e1180
Background
This study aims to estimate the age-specific risks of clinical dengue attack (i.e., the risk of symptomatic dengue among the total number of dengue virus (DENV) infections) during primary and secondary infections.Methods
We analyzed two pieces of epidemiological information in Binh Thuan province, southern Vietnam, i.e., age-specific seroprevalence and a community-wide longitudinal study of clinical dengue attack. The latter data set stratified febrile patients with DENV infection by age as well as infection parity. A simple modeling approach was employed to estimate the age-specific risks of clinical dengue attack during primary and secondary infections.Results
Using the seroprevalence data, the force of infection was estimated to be 11.7% (95% confidence intervals (CI): 10.8–12.7) per year. Median age (and the 25–75 percentiles) of dengue fever patients during primary and secondary infections were 12 (9–20) and 20 (14–31) years, respectively. The estimated age-specific risk of clinical dengue increases as a function of age for both primary and secondary infections; the estimated proportion of symptomatic patients among the total number of infected individuals was estimated to be <7% for those aged <10 years for both primary and secondary infections, but increased as patients become older, reaching to 8–11% by the age of 20 years.Conclusions/Significance
For both primary and secondary infections, higher age at DENV infection was shown to result in higher risk of clinical attack. Age as an important modulator of clinical dengue explains recent increase in dengue notifications in ageing countries in Southeast Asia, and moreover, poses a paradoxical problem of an increase in adult patients resulting from a decline in the force of infection, which may be caused by various factors including time-dependent variations in epidemiological, ecological and demographic dynamics. 相似文献162.
Nguyen QB Kadotani N Kasahara S Tosa Y Mayama S Nakayashiki H 《Molecular microbiology》2008,68(6):1348-1365
We developed an RNA-silencing vector, pSilent-Dual1 (pSD1), with a convergent dual promoter system that provides a high-throughput platform for functional genomics research in filamentous fungi. In the pSD1 system, the target gene was designed to be transcribed as a chimeric RNA with enhanced green fluorescent protein (eGFP) RNA. This enabled us to efficiently screen the resulting transformants using GFP fluorescence as an indicator of gene silencing. A model study with the eGFP gene showed that pSD1-based vectors induced gene silencing via the RNAi pathway with slightly lower efficiency than did hairpin eGFP RNA-expressing vectors. To demonstrate the applicability of the pSD1 system for elucidating gene function in the rice-blast fungus Magnaporthe oryzae , 37 calcium signalling-related genes that include almost all known calcium-signalling proteins in the genome were targeted for gene silencing by the vector. Phenotypic analyses of the silenced transformants showed that at least 26, 35 and 15 of the 37 genes examined were involved in hyphal growth, sporulation and pathogenicity, respectively, in M. oryzae. These included several novel findings such as that Pmc1 -, Spf1 - and Neo1 -like Ca2+ pumps, calreticulin and calpactin heavy chain were essential for fungal pathogenicity. 相似文献
163.
Hoang Vu Phan Quoc Viet Nguyen Quang Tri Truong Tien Van Truong Hoon Cheol Park Nam Seo Goo Doyoung Byun Min Jun Kim 《仿生工程学报(英文版)》2012,9(4):391-401
We briefly summarized how to design and fabricate an insect-mimicking flapping-wing system and demonstrate how to implement inherent pitching stability for stable vertical takeoff.The effect of relative locations of the Center of Gravity (CG) and the mean Aerodynamic Center (AC) on vertical flight was theoretically examined through static force balance consideration.We conducted a series of vertical takeoff tests in which the location of the mean AC was determined using an unsteady Blade Element Theory (BET) previously developed by the authors.Sequential images were captured during the takeoff tests using a high-speed camera.The results demonstrated that inherent pitching stability for vertical takeoff can be achieved by controlling the relative position between the CG and the mean AC of the flapping system. 相似文献
164.
9-Fluorenylmethoxycarbonylpyroglutamate, a side-product of derivatization of glutamate with 9-fluorenylmethyl chloroformate: a warning 总被引:1,自引:0,他引:1
H J Keller K Quang Do M Zollinger K H Winterhalter M Cuénod 《Analytical biochemistry》1987,166(2):431-434
9-Fluorenylmethyl chloroformate derivatization is widely used for determinations of amino acids in biological material. The derivatization of glutamate leads to the formation of 9-fluorenylmethoxycarbonylpyroglutamate as a side-product, which is thus a methodological artifact. 相似文献
165.
Three‐dimensional microscale modelling of CO2 transport and light propagation in tomato leaves enlightens photosynthesis 下载免费PDF全文
Quang Tri Ho Herman N. C. Berghuijs Rodrigo Watté Pieter Verboven Els Herremans Xinyou Yin Moges A. Retta Ben Aernouts Wouter Saeys Lukas Helfen Graham D. Farquhar Paul C. Struik Bart M. Nicolaï 《Plant, cell & environment》2016,39(1):50-61
We present a combined three‐dimensional (3‐D) model of light propagation, CO2 diffusion and photosynthesis in tomato (Solanum lycopersicum L.) leaves. The model incorporates a geometrical representation of the actual leaf microstructure that we obtained with synchrotron radiation X‐ray laminography, and was evaluated using measurements of gas exchange and leaf optical properties. The combination of the 3‐D microstructure of leaf tissue and chloroplast movement induced by changes in light intensity affects the simulated CO2 transport within the leaf. The model predicts extensive reassimilation of CO2 produced by respiration and photorespiration. Simulations also suggest that carbonic anhydrase could enhance photosynthesis at low CO2 levels but had little impact on photosynthesis at high CO2 levels. The model confirms that scaling of photosynthetic capacity with absorbed light would improve efficiency of CO2 fixation in the leaf, especially at low light intensity. 相似文献
166.
Quang Minh Dinh Jian Guang Qin Sabine Dittmann Dinh Dac Tran 《Ichthyological Research》2017,64(2):179-189
Diet composition and feeding habits of the burrowing fish Parapocryptes serperaster were investigated on different fish sizes across dry and wet seasons in the Mekong Delta, Vietnam. The gut length was positively related to fish length; the gut length was 1.57 ± 0.30 times the total length, which is in the range for omnivore (1–3). Detritus, algae and copepods were the main food items in the foregut. The diet composition showed seasonal and intraspecific variations in all fish sizes. The diet diversity varied with fish size and the dry-wet season pattern, and small fish had a higher diet diversity than large fish. The diet evenness index and Costello graphic analysis indicate that this goby is a generalist feeder and feeds mainly on detritus, followed by diatoms, and could obtain food from the bottom and the water column. The feeding intensity of P. serperaster was higher in the wet season than in the dry season, but was not significantly affected by fish size. The P. serperaster fed on Navicula spp. in the wet season, but on Nitzschia spp. in the dry season. The understanding of food and feeding habits of P. serperaster contributes to our knowledge on feeding adaptation of small-bodied bottom-dwelling gobies to the mud flat habitats in tropical monsoonal regions. 相似文献
167.
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169.
The human body is a highly familiar and socially very important object. Does this mean that the human body has a special status with respect to visual attention? In the current paper we tested whether people in natural scenes attract attention and “pop out” or, alternatively, are at least searched for more efficiently than targets of another category (machines). Observers in our study searched a visual array for dynamic or static scenes containing humans amidst scenes containing machines and vice versa. The arrays consisted of 2, 4, 6 or 8 scenes arranged in a circular array, with targets being present or absent. Search times increased with set size for dynamic and static human and machine targets, arguing against pop out. However, search for human targets was more efficient than for machine targets as indicated by shallower search slopes for human targets. Eye tracking further revealed that observers made more first fixations to human than to machine targets and that their on-target fixation durations were shorter for human compared to machine targets. In summary, our results suggest that searching for people in natural scenes is more efficient than searching for other categories even though people do not pop out. 相似文献
170.
Reassortant DS‐1‐like G1P[4] Rotavirus A strains generated from co‐circulating strains in Vietnam, 2012/2013 下载免费PDF全文
Chantal Ama Agbemabiese Toyoko Nakagomi Minh Quang Nguyen Punita Gauchan Osamu Nakagomi 《Microbiology and immunology》2017,61(8):328-336