The effect of parental rearing conditions on offspring life history in Anopheles stephensi

Background The environmental conditions experienced by parents are increasingly recognized to impact the success of offspring. Little is known on the presence of such parental effects in Anopheles. If present, parental effects could influence mosquito breeding programmes, some malaria control measures and have epidemiological and evolutionary consequences. Methods The presence of parental effects on offspring emergence time, size, survival, blood meal size and fecundity in laboratory reared An. stephensi were tested. Results Parental rearing conditions did not influence the time taken for offspring to emerge, or their size or survival as adults. However, parental effects were influential in determining the fecundity of daughters. Counter-intuitively, daughters of parents reared in low food conditions produced larger egg clutches than daughters of parents reared in high food conditions. Offspring reared in low food conditions took larger blood meals if their parents had also experienced a low food environment. Conclusion So far as we are aware, this is the first evidence of parental effects on progeny in Anophele

Time-varying managerial overconfidence and pecking order preference

This paper examines whether managerial overconfidence enhances or weakens pecking order preference. We construct time-varying managerial words-based (i.e. tone of Chairman’s Statement) and action-based (i.e. firm investment and directors’ trading) overconfidence measures. Both optimistic tone and industry-adjusted investment have significant and negative impacts on the pecking order coefficient in the Shyam-Sunder and Myers (J Financ Econ 51:219–244, 1999) regression framework. Overconfident managers tend to use more equity than debt to finance deficits. This new evidence is consistent with the proposition that overconfident managers who underestimate the riskiness of future earnings believe that their debt (equity) is undervalued (overvalued) and therefore prefer equity to debt financing. Thus, managerial overconfidence can lead to a reverse pecking order preference. We also find that managerial overconfidence significantly weakens pecking order preference especially in firms with high earnings volatility and small firms

Geographical variation in vegetative growth and sexual reproduction of the invasive Spartina alterniflora in China

Phenotypic variation plays an important role in successful plant invasions. The spread of invasive species over large geographic ranges may be facilitated if plants can match their phenotype to local abiotic conditions. Spartina alterniflora, native to the United States, was introduced into China in 1979 and has spread over 19° of latitude along the eastern coast of China. We studied patterns in vegetative growth and sexual reproduction of S. alterniflora at 22 sites at 11 geographic locations over a latitudinal gradient of 2000 km from Tanggu (39.05°N, high latitude) to Leizhou (20.90°N, low latitude) in China. We further evaluated the basis of phenotypic differences by growing plants from across the range in a common garden for 2 growing seasons. We found distinct latitudinal clines in plant height, shoot density and sexual reproduction across latitude. Some traits exhibited linear relationships with latitude; others exhibited hump-shaped relationships. We identified correlations between plant traits and abiotic conditions such as mean annual temperature, growing degree days, tidal range and soil nitrogen content. However, geographic variation in all but one trait disappeared in the common garden, indicating that variation largely due to phenotypic plasticity. Only a slight tendency for latitudinal variation in seed set persisted for 2 years in the common garden, suggesting that plants may be evolving genetic clines for this trait. Synthesis. The rapid spread of Spartina alterniflora (S. alterniflora) in China has probably been facilitated by phenotypic plasticity in growth and reproductive traits. We found little evidence for the evolution of genetic clines in China, even though these exist for some traits in the native range. The considerable variation among clones, within provenances, that persisted in the common garden suggests a potential for the evolution of geographic clines in the future. Low fecundity of low-latitude S. alterniflora populations in China might result in a slower spread at low latitudes, but S. alterniflora is likely to continue to spread rapidly at high latitudes in China and into the Korean peninsula. The rapid spread of Spartina alterniflora (S. alterniflora) in China has probably been facilitated by phenotypic plasticity in growth and reproductive traits. We found little evidence for the evolution of genetic clines in China, even though these exist for some traits in the native range. The considerable variation among clones, within provenances, that persisted in the common garden suggests a potential for the evolution of geographic clines in the future. Low fecundity of low latitude S. alterniflora populations in China might result in a slower spread at low latitudes, but S. alterniflora is likely to continue to spread rapidly at high latitudes in China and into the Korean peninsula. Journal of Ecolog

Geographical variation in vegetative growth and sexual reproduction of the invasive Spartina alterniflora in China

Phenotypic variation plays an important role in successful plant invasions. The spread of invasive species over large geographic ranges may be facilitated if plants can match their phenotype to local abiotic conditions. Spartina alterniflora, native to the United States, was introduced into China in 1979 and has spread over 19° of latitude along the eastern coast of China. We studied patterns in vegetative growth and sexual reproduction of S. alterniflora at 22 sites at 11 geographic locations over a latitudinal gradient of 2000 km from Tanggu (39.05°N, high latitude) to Leizhou (20.90°N, low latitude) in China. We further evaluated the basis of phenotypic differences by growing plants from across the range in a common garden for 2 growing seasons. We found distinct latitudinal clines in plant height, shoot density and sexual reproduction across latitude. Some traits exhibited linear relationships with latitude; others exhibited hump-shaped relationships. We identified correlations between plant traits and abiotic conditions such as mean annual temperature, growing degree days, tidal range and soil nitrogen content. However, geographic variation in all but one trait disappeared in the common garden, indicating that variation largely due to phenotypic plasticity. Only a slight tendency for latitudinal variation in seed set persisted for 2 years in the common garden, suggesting that plants may be evolving genetic clines for this trait. Synthesis. The rapid spread of Spartina alterniflora (S. alterniflora) in China has probably been facilitated by phenotypic plasticity in growth and reproductive traits. We found little evidence for the evolution of genetic clines in China, even though these exist for some traits in the native range. The considerable variation among clones, within provenances, that persisted in the common garden suggests a potential for the evolution of geographic clines in the future. Low fecundity of low-latitude S. alterniflora populations in China might result in a slower spread at low latitudes, but S. alterniflora is likely to continue to spread rapidly at high latitudes in China and into the Korean peninsula. The rapid spread of Spartina alterniflora (S. alterniflora) in China has probably been facilitated by phenotypic plasticity in growth and reproductive traits. We found little evidence for the evolution of genetic clines in China, even though these exist for some traits in the native range. The considerable variation among clones, within provenances, that persisted in the common garden suggests a potential for the evolution of geographic clines in the future. Low fecundity of low latitude S. alterniflora populations in China might result in a slower spread at low latitudes, but S. alterniflora is likely to continue to spread rapidly at high latitudes in China and into the Korean peninsula. Journal of Ecolog

Rare variants in Fanconi anemia genes are enriched in acute myeloid leukemia

Abstract not availableKyaw Ze Ya Maung, Paul J. Leo, Mahmoud Bassal, Debora A. Casolari, James X Gray, Sarah C. Bray, Stephen Pederson, Deepak Singhal, Saumya E. Samaraweera, Tran Nguyen, Gökhan Cildir, Mhairi Marshall, Adam Ewing, Emma L. Duncan, Matthew A. Brown, Russell Saal, Vinay Tergaonkar, Luen Bik To, Paula Marlton, Devinder Gill, Ian Lewis, Andrew J Deans, Anna L Brown, Richard J D’Andrea and Thomas J Gond

An ultrasensitive reverse transcription polymerase chain reaction assay to detect asymptomatic low-density Plasmodium falciparum and Plasmodium vivax infections in small volume blood samples

BACKGROUND: Highly sensitive, scalable diagnostic methods are needed to guide malaria elimination interventions. While traditional microscopy and rapid diagnostic tests (RDTs) are suitable for the diagnosis of symptomatic malaria infection, more sensitive tests are needed to screen for low-density, asymptomatic infections that are targeted by interventions aiming to eliminate the entire reservoir of malaria infection in humans. METHODS: A reverse transcription polymerase chain reaction (RT- PCR) was developed for multiplexed detection of the 18S ribosomal RNA gene and ribosomal RNA of Plasmodium falciparum and Plasmodium vivax. Simulated field samples stored for 14 days with sample preservation buffer were used to assess the analytical sensitivity and specificity. Additionally, 1750 field samples from Southeastern Myanmar were tested both by RDT and ultrasensitive RT-PCR. RESULTS: Limits of detection (LoD) were determined under simulated field conditions. When 0.3 mL blood samples were stored for 14 days at 28 °C and 80 % humidity, the LoD was less than 16 parasites/mL for P. falciparum and 19.7 copies/µL for P. vivax (using a plasmid surrogate), about 10,000-fold lower than RDTs. Of the 1739 samples successfully evaluated by both ultrasensitive RT-PCR and RDT, only two were RDT positive while 24 were positive for P. falciparum, 108 were positive for P. vivax, and 127 were positive for either P. vivax and/or P. falciparum using ultrasensitive RT-PCR. CONCLUSIONS: This ultrasensitive RT-PCR method is a robust, field-tested screening method that is vastly more sensitive than RDTs. Further optimization may result in a truly scalable tool suitable for widespread surveillance of low-level asymptomatic P. falciparum and P. vivax parasitaemia. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12936-015-1038-z) contains supplementary material, which is available to authorized users