2,143 research outputs found
Tank construction for space vehicles Patent
Liquid propellant tank design with semitoroidal bulkhea
An Ecological Study of the Prairie and Sedge Meadow Communities of Richardson Wildlife Foundation
ID: 8259; Issue date not indicated on report.INHS Technical Report prepared for Terry Moyer, Richardson Wildlife Foundatio
Characterization of Newly Revealed Sequences in the Infectious Myonecrosis Virus Genome in \u3ci\u3eLitopenaeus vannamei\u3c/i\u3e
Infectious myonecrosis virus (IMNV) causes significant economic losses in farmed shrimp, where associated mortality in ponds can reach 70%. To explore host/pathogen interactions, a next-generation sequencing approach using lymphoid organ tissue from IMNV-infected Litopenaeus vannamei shrimp was conducted. Preliminary sequence assembly of just the virus showed that there were at least an additional 639 bp at the 5ā² terminus and 23 nt at the 3ā² terminus as compared with the original description of the IMNV genome (7561 nt). Northern blot and reverse transcription-PCR analysis confirmed the presence of novel sequence at both ends of the genome. Using 5ā² RACE, an additional 4 nt were discovered; 3ā² RACE confirmed the presence of 22 bp rather than 23 bp of sequence. Based on these data, the IMNV genome is 8226 bp in length. dsRNA was used to trigger RNA interference (RNAi) and suppress expression of the newly revealed genome sections at the 5ā² end of the IMNV genome in IMNV-infected L. vannamei. An RNAi trigger targeting a 376 bp length of the 5ā² UTR did not improve survival of infected shrimp. In contrast, an RNAi trigger targeting a 381 bp sequence in ORF1 improved survival to 82.2% as compared with 2.2% survival in positive control animals. These studies revealed the importance of the new genome sections to produce high-titre infection, and associated disease and mortality, in infected shrimp
More than range exposure: global ottersā vulnerability to climate change
Climate change impact on species is commonly assessed by predicting speciesā range change, a measure of a speciesā extrinsic exposure. However, this is only one dimension of speciesā vulnerability to climate change. Spatial arrangement of suitable habitats (e.g., fragmentation), their degree of protection or human disturbance, as well as speciesā intrinsic sensitivity, such as climatic tolerances, are often neglected. Here, we consider components of speciesā intrinsic sensitivity to climate change (climatic niche specialization and marginality) together with components of extrinsic exposure (changes in range extent, fragmentation, coverage of protected areas, and human footprint) to develop an integrated vulnerability index to climate change for worldās freshwater otters. As top freshwater predators, otters are among the most vulnerable mammals, with most species being threatened by habitat loss and degradation. All dimensions of climate change exposure were based on present and future predictions of species distributions. Annual mean temperature, mean diurnal temperature range, mean temperature of the wettest quarter, precipitation during the wettest quarter, and precipitation seasonality prove the most important variables for otters. All species are vulnerable to climate change, with global vulnerability index ranging from -0,19 for Lontra longicaudis to -36,9 for Aonyx congicus. However, we found that, for a given species, climate change can have both positive and negative effects on different components of extrinsic exposure, and that measures of speciesā sensitivity are not necessarily congruent with measures of exposure. For instance, the range of all African species would be negatively affected by climate change, but their different sensitivity offers a more (Hydrictis maculicollis, Aonyx capensis) or less (Aonyx congicus) pessimistic perspective on their ability to cope with climate change. Also, highly sensitive species like the South-American Pteronura brasiliensis, Lontra provocax, and Lutra perspicillata might face no exposure to climate change. For the Asian Lutra sumatrana, climate change would instead lead to an increased, less fragmented, and more protected range extent, but the range extent would also be shifted into areas with higher human disturbances. Our study represents a balanced example of how to develop an index aimed at comparatively evaluating vulnerability to climate change of different species by combining different aspects of sensitivity and exposure, providing additional information on which to base more efficient conservation strategies
Note on Ehrlichia chaffeensis, Ehrlichia ewingii, and āBorrelia lonestariā infection in lone star ticks (Acari: Ixodidae), Nebraska, USA
The lone star tick, Amblyomma americanum (L.) (Acari: Ixodidae), is established in southeastern Nebraska yet the prevalence of tick-associated microorganisms is not known. An initial PCR-based analysis for Ehrlichia chaffeensis, Ehrlichia ewingii, and Borrelia infection in host-seeking adult ticks collected in southeast Nebraska was conducted. A total of 251 adult ticks collected in six sites in southeast Nebraska were tested. E. chaffeensis, E. ewingii, and Borrelia spp. were present, and the prevalence of each was approximately 1.6%. This study demonstrates that Ehrlichia spp. are present in Nebraska lone star tick populations
Characterization of Newly Revealed Sequences in the Infectious Myonecrosis Virus Genome in \u3ci\u3eLitopenaeus vannamei\u3c/i\u3e
Infectious myonecrosis virus (IMNV) causes significant economic losses in farmed shrimp, where associated mortality in ponds can reach 70%. To explore host/pathogen interactions, a next-generation sequencing approach using lymphoid organ tissue from IMNV-infected Litopenaeus vannamei shrimp was conducted. Preliminary sequence assembly of just the virus showed that there were at least an additional 639 bp at the 5ā² terminus and 23 nt at the 3ā² terminus as compared with the original description of the IMNV genome (7561 nt). Northern blot and reverse transcription-PCR analysis confirmed the presence of novel sequence at both ends of the genome. Using 5ā² RACE, an additional 4 nt were discovered; 3ā² RACE confirmed the presence of 22 bp rather than 23 bp of sequence. Based on these data, the IMNV genome is 8226 bp in length. dsRNA was used to trigger RNA interference (RNAi) and suppress expression of the newly revealed genome sections at the 5ā² end of the IMNV genome in IMNV-infected L. vannamei. An RNAi trigger targeting a 376 bp length of the 5ā² UTR did not improve survival of infected shrimp. In contrast, an RNAi trigger targeting a 381 bp sequence in ORF1 improved survival to 82.2% as compared with 2.2% survival in positive control animals. These studies revealed the importance of the new genome sections to produce high-titre infection, and associated disease and mortality, in infected shrimp
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