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121.
Vu Quang Nam 《Nordic Journal of Botany》2014,32(6):815-818
A new species of the family Magnoliaceae, Magnolia cattienensis Q. N. Vu from Cát Tiên National Park, in the Lâm ??ng Province, south of Vietnam is described and illustrated. Magnolia cattienensis is most closely related to M. henryi Dunn, but differs by narrowly cuneate and gradually attenuate bases of the leaves (vs broadly cuneate, not attenuated), pilose pedicles (vs glabrous), and villose peduncles (vs glabrescent), pubescent gynoecium (vs glabrous), and fewer mature carpels (26–30 vs 85–90) with dense trichomes (vs glabrous). 相似文献
122.
Priya Joyce Scott Hermann Anthony O'Connell Quang Dinh Leonard Shumbe Prakash Lakshmanan 《Plant biotechnology journal》2014,12(4):411-424
Future genetic improvement of sugarcane depends, in part, on the ability to produce high‐yielding transgenic cultivars with improved traits such as herbicide and insect resistance. Here, transgenic sugarcane plants generated by different transformation methods were assessed for field performance over 3 years. Agrobacterium‐mediated (Agro) transgenic events (35) were produced using four different Agrobacterium tumefaciens strains, while biolistic (Biol) transgenic events (48) were produced using either minimal linearized DNA (LDNA) transgene cassettes with 5′, 3′ or blunt ends or whole circular plasmid (PDNA) vectors containing the same transgenes. A combined analysis showed a reduction in growth and cane yield in Biol, Agro as well as untransformed tissue culture (TC) events, compared with the parent clone (PC) Q117 (no transformation or tissue culture) in the plant, first ratoon and second ratoon crops. However, when individual events were analysed separately, yields of some transgenic events from both Agro and Biol were comparable to PC, suggesting that either transformation method can produce commercially suitable clones. Interestingly, a greater percentage of Biol transformants were similar to PC for growth and yield than Agro clones. Crop ratoonability and sugar yield components (Brix%, Pol%, and commercial cane sugar (CCS)) were unaffected by transformation or tissue culture. Transgene expression remained stable over different crop cycles and increased with plant maturity. Transgene copy number did not influence transgene expression, and both transformation methods produced low transgene copy number events. No consistent pattern of genetic changes was detected in the test population using three DNA fingerprinting techniques. 相似文献
123.
A genetic map of Peromyscus with chromosomal assignment of linkage groups (a Peromyscus genetic map)
Jane Kenney-Hunt Adrienne Lewandowski Travis C. Glenn Julie L. Glenn Olga V. Tsyusko Rachel J. O’Neill Judy Brown Clifton M. Ramsdell Quang Nguyen Tony Phan Kimberly R. Shorter Michael J. Dewey Gabor Szalai Paul B. Vrana Michael R. Felder 《Mammalian genome》2014,25(3-4):160-179
The rodent genus Peromyscus is the most numerous and species-rich mammalian group in North America. The naturally occurring diversity within this genus allows opportunities to investigate the genetic basis of adaptation, monogamy, behavioral and physiological phenotypes, growth control, genomic imprinting, and disease processes. Increased genomic resources including a high quality genetic map are needed to capitalize on these opportunities. We produced interspecific hybrids between the prairie deer mouse (P. maniculatus bairdii) and the oldfield mouse (P. polionotus) and scored meiotic recombination events in backcross progeny. A genetic map was constructed by genotyping of backcross progeny at 185 gene-based and 155 microsatellite markers representing all autosomes and the X-chromosome. Comparison of the constructed genetic map with the molecular maps of Mus and Rattus and consideration of previous results from interspecific reciprocal whole chromosome painting allowed most linkage groups to be unambiguously assigned to specific Peromyscus chromosomes. Based on genomic comparisons, this Peromyscus genetic map covers ~83 % of the Rattus genome and 79 % of the Mus genome. This map supports previous results that the Peromyscus genome is more similar to Rattus than Mus. For example, coverage of the 20 Rattus autosomes and the X-chromosome is accomplished with only 28 segments of the Peromyscus map, but coverage of the 19 Mus autosomes and the X-chromosome requires 40 chromosomal segments of the Peromyscus map. Furthermore, a single Peromyscus linkage group corresponds to about 91 % of the rat and only 76 % of the mouse X-chromosomes. 相似文献
124.
Trung Thanh Nguyen Thomas Koellner Quang Bao Le Cosmas Kombat Lambini Ikchang Choi Hio-jung Shin Van Dien Pham 《Biodiversity and Conservation》2014,23(4):811-830
The area of degraded forests in Vietnam is substantial, currently about 3.1 million ha of which about 1.7 million ha (55 %) were granted to individual farms for reforestation. However, the result of farmers’ reforestation efforts is limited. We aimed to examine the financial return, technical efficiency, and factors determining reforestation with a native tree species (Canarium album) by farms. Our results showed that reforestation with C. album is less financially profitable than that with an exotic tree species (Acacia mangium) as the alternative land use option. The subsidy from the government is found insufficient to compensate for the income losses of farmers participating in reforestation with the native tree species. Reforestation with C. album could be more successful if participating farmers were equipped to be more technically efficient. Finally, our findings clearly showed that the security of forest land property rights and the provision of forest extension services are among the determinants of participation in, and the subsequent success of reforestation with C. album. 相似文献
125.
Visualization of molecular structures aids in the understanding of structural and functional roles of biological macromolecules.
Macromolecular transport between the cell nucleus and cytoplasm is facilitated by the nuclear pore complex (NPC). The ring
structure of the NPC is large and contains several distinct proteins (nucleoporins) which function as a selective gate for the passage
of certain molecules into and out of the nucleus. In this note we demonstrate the utility of a python code that allows direct
mapping of the physiochemical properties of the constituent nucleoporins on the scaffold of the yeast NPC׳s cytoplasmic view. We
expect this tool to be useful for researchers to visualize the NPC based on their physiochemical properties and how it alters when
specific mutations are introduced in one or more of the nucleoporins. The code developed using Python is available freely from the
authors. 相似文献
126.
Hoa L. Nguyen Quang Ngoc Nguyen Duc Anh Ha Dat Tuan Phan Nguyen Hanh Nguyen Robert J. Goldberg 《PloS one》2014,9(10)
Background
Cardiovascular disease is one of the leading causes of morbidity and mortality in Vietnam. We conducted a pilot study of Hanoi residents hospitalized with a first acute myocardial infarction (AMI) at the Vietnam National Heart Institute in Hanoi for purposes of describing the prevalence of cardiovascular (CVD) and non-CVD comorbidities and their impact on hospital management, in-hospital clinical complications, and short-term mortality in these patients.Methods
The study population consisted of 302 Hanoi residents hospitalized with a first AMI at the largest tertiary care medical center in Hanoi in 2010.Results
The average age of study patients was 66 years and one third were women. The proportions of patients with none, any 1, and ≥ 2 CVD comorbidities were 34%, 42%, and 24%, respectively. Among the CVD comorbidities, hypertension was the most commonly reported (59%). There were decreasing trends in the proportion of patients who were treated with effective cardiac medications and coronary interventions as the number of CVD comorbidities increased. Patients with multiple CVD comorbidities tended to develop acute clinical complications and die at higher rates during hospitalization compared with patients with no CVD comorbidities (Odds Ratio: 1.40; 95% Confidence Interval: 0.40–4.84).Conclusions
Our data suggest that patients with multiple cardiac comorbidities tended to experience high in-hospital death rates in the setting of AMI. Full-scale surveillance of Hanoi residents hospitalized with AMI at all Hanoi hospitals is needed to confirm these findings. Effective strategies to manage Vietnamese patients hospitalized with AMI who have multiple comorbidities are warranted to improve their short-term prognosis. 相似文献127.
Dussart P Baril L Petit L Beniguel L Quang LC Ly S Azevedo Rdo S Meynard JB Vong S Chartier L Diop A Sivuth O Duong V Thang CM Jacobs M Sakuntabhai A Nunes MR Huong VT Buchy P Vasconcelos PF 《PLoS neglected tropical diseases》2012,6(1):e1482
Background
Dengue has emerged as the most important vector-borne viral disease in tropical areas. Evaluations of the burden and severity of dengue disease have been hindered by the frequent lack of laboratory confirmation and strong selection bias toward more severe cases.Methodology
A multinational, prospective clinical study was carried out in South-East Asia (SEA) and Latin America (LA), to ascertain the proportion of inapparent dengue infections in households of febrile dengue cases, and to compare clinical data and biological markers from subjects with various dengue disease patterns. Dengue infection was laboratory-confirmed during the acute phase, by virus isolation and detection of the genome. The four participating reference laboratories used standardized methods.Principal Findings
Among 215 febrile dengue subjects—114 in SEA and 101 in LA—28 (13.0%) were diagnosed with severe dengue (from SEA only) using the WHO definition. Household investigations were carried out for 177 febrile subjects. Among household members at the time of the first home visit, 39 acute dengue infections were detected of which 29 were inapparent. A further 62 dengue cases were classified at early convalescent phase. Therefore, 101 dengue infections were found among the 408 household members. Adding these together with the 177 Dengue Index Cases, the overall proportion of dengue infections among the study participants was estimated at 47.5% (278/585; 95% CI 43.5–51.6). Lymphocyte counts and detection of the NS1 antigen differed significantly between inapparent and symptomatic dengue subjects; among inapparent cases lymphocyte counts were normal and only 20% were positive for NS1 antigen. Primary dengue infection and a specific dengue virus serotype were not associated with symptomatic dengue infection.Conclusion
Household investigation demonstrated a high proportion of household members positive for dengue infection, including a number of inapparent cases, the frequency of which was higher in SEA than in LA. 相似文献128.
Transport of CO2 in leaves was investigated by combining a 2-D, microscale CO2 transport model with photosynthesis kinetics in wheat (Triticum aestivum L.) leaves. The biophysical microscale model for gas exchange featured an accurate geometric representation of the actual 2-D leaf tissue microstructure and accounted for diffusive mass exchange of CO2. The resulting gas transport equations were coupled to the biochemical Farquhar-von Caemmerer-Berry model for photosynthesis. The combined model was evaluated using gas exchange and chlorophyll fluorescence measurements on wheat leaves. In general a good agreement between model predictions and measurements was obtained, but a discrepancy was observed for the mesophyll conductance at high CO2 levels and low irradiance levels. This may indicate that some physiological processes related to photosynthesis are not incorporated in the model. The model provided detailed insight into the mechanisms of gas exchange and the effects of changes in ambient CO2 concentration or photon flux density on stomatal and mesophyll conductance. It represents an important step forward to study CO2 diffusion coupled to photosynthesis at the leaf tissue level, taking into account the leaf''s actual microstructure. 相似文献
129.
F(2) and BC(1) populations derived from the cross between 02428 / Rathu Heenati were used to investigate small brown planthopper (SBPH) resistance. Using the F(2) population, three QTLs for antixenosis against SBPH were located on chromosomes 2, 5 and 6, and accounted for 30.75% of the phenotypic variance; three QTLs for antibiosis against SBPH were detected on chromosomes 8, 9 and 12. qSBPH5-c explaining 7.21% of phenotypic variance for antibiosis was identified on chromosome 5 using the BC(1) population. A major QTL, qSBPH12-a1, explained about 40% of the phenotypic variance, and a minor QTL, qSBPH4-a, was detected by the SSST method in both the F(2) and BC(1) populations. The QTLs indentified in the present study will be useful for marker assisted selection of SBPH resistance in rice. 相似文献
130.
Quang Nam Vu 《Nordic Journal of Botany》2012,30(5):575-577
Michelia xianianhei Q. N. Vu, a new species of Michelia from Dien Bien Province, northern Vietnam is described and illustrated. Michelia xianianhei is closely related to M. balansae (Aug. DC.) Dandy but differs mainly in the young twigs, petioles, terminal buds and brachyblasts being densely greyish silky hairy, 9–11 yellowish tepals, bigger fruit, and shorter fruiting gynophore. 相似文献