Cell walls were prepared from the yeastlike and mycelial phases (YP and MP) of Histoplasma capsulatum and from Saccharomyces cerevisiae by mechanical disruption and washing. Lipids were extracted with methanol-ether, chloroform, and acidified methanol:ether; a final extraction was made with ethylenediamine. The lipid contents of H. capsulatum YP and MP walls were about the same. Qualitative and...

We include new data in an updated analysis of helium in low metallicity extragalactic H II regions with the goal of deriving the primordial abundance of He (YP). We show that the new observations of Izotov et al. (ITL) are consistent with previous data. However they should not be taken in isolation to determine YP due to the lack of sufficiently low metallicity points. We use the extant data in...

BACKGROUND Arguments supporting the involvement of users in research have even more weight when involving the public in systematic reviews of research. We aimed to explore the potential for public involvement in systematic reviews of observational and qualitative studies. METHODS Two consultative workshops were carried out with a group of young people (YP) aged 12-17 years to examine two ongo...

By extrapolating to O/H = N/H = 0 the empirical correlations Y –O/H and Y –N/H defined by a relatively large sample of ∼ 45 Blue Compact Dwarfs (BCDs), we have obtained a primordial Helium mass fraction Yp= 0.2443±0.0015 with dY /dZ = 2.4±1.0. This result is in excellent agreement with the average Yp= 0.2452±0.0015 determined in the two most metal-deficient BCDs known, I Zw 18 (Z⊙/50) and SBS 0...

competition [37] is suggested to study the principles of competition in their most generic form [8–10]. Consider a complex competitive system, which has a large number of autonomous elements engaged in competition with each other. The evolution of a competitive system involves a process of determining a winner and a loser for competition between any two elements of the system. The non-conservat...

breeding for environmental stress is one of the most important goals in plant breeding. among stresses, drought stress has high influencing on limitation of wheat production. so, in order to find the best drought tolerant genotypes, 24 genotypes were planted in three separate experiments in ardebil: one with optimum irrigation (control), another with water stress at pre-anthesis stage and the o...

Yersinia pestis (Yp) causes the re-emerging disease plague, and is classified by the CDC and NIAID as a highest priority (Category A) pathogen. Currently, there is no approved human vaccine available and advances in early diagnostics and effective therapeutics are urgently needed. A deep understanding of the mechanisms of host response to Yp infection can significantly advance these three areas...

The human X and Y chromosomes share many blocks of similar DNA sequence. We conducted mapping and nucleotide sequencing studies of extensive, multi-megabase homologies between Yp and Xq21, which do not recombine during male meiosis. We confirmed and built upon previous evidence that a Yp inversion had occurred during evolution: a single contiguous segment of Xq21 is homologous to two non-contig...

We have used recent observations of helium-4, nitrogen and oxygen from some four dozen, low metallicity, extra-galactic HII regions to define mean N versus O, He versus N and He versus O relations which are extrapolated to zero metallicity to determine the primordial He mass fraction YP . The data and various subsets of the data, selected on the basis of nitrogen and oxygen, are all consistent ...

Crop simulation models can be used to estimate impact of current and future climates on crop yields and food security, but require long-term historical daily weather data to obtain robust simulations. In many regions where crops are grown, daily weather data are not available. Alternatively, gridded weather databases (GWD) with complete terrestrial coverage are available, typically derived from...