2,414 research outputs found
AN ECONOMIC ANALYSIS OF GENETIC INFORMATION: LEPTIN GENOTYPING IN FED CATTLE
The use of genetic knowledge is widespread in crop production but is just recently being utilized in livestock production. This study investigates the economic value to feedlots of a polymorphism in the bovine leptin gene. Previous studies indicate that this polymorphism is associated with fat deposition. Since fed cattle are often priced on a grid that considers both yield and quality grades, fat deposition is an important factor in the value and profitability of fed cattle. Using data from 590 crossbred steers and heifers, we estimate growth curves for relevant biological traits, both with and without genotypic information. Using the resulting functions, we then simulate carcass traits to various days-on-feed and compute the associated profit under three price grids. Maximum profits are determined in an unconstrained profit maximization model and in a model that constrains cattle to be marketed in 45-head "potloads." Results indicate that leptin genotypic knowledge has little impact on optimal days-on-feed but may play a role in valuing feeder cattle. The differences in value of cattle varied by as much as $37 per head between genotypes.genetics, leptin genotype, beef cattle, value of information, Livestock Production/Industries,
Editorial : Adult neurogenesis as a regenerative strategy for brain repair
Funding Information: This work was supported by Biological Sciences Research Council (BBSRC) BB/W008068/1 to DB, National Research Foundation of Korea (NRF) (2019R1A2C1003958 and 2021R1A4A5028966) to K-OC, and NIH (R01CA242158 and R01AG058560) to M-HJ.Peer reviewedPublisher PD
Radial glial cells in the adult dentate gyrus : What are they and where do they come from?
Peer reviewedPublisher PD
Confidence Is the Bridge between Multi-stage Decisions
Demanding tasks often require a series of decisions to reach a goal. Recent progress in perceptual decision-making has served to unite decision accuracy, speed, and confidence in a common framework of bounded evidence accumulation, furnishing a platform for the study of such multi-stage decisions. In many instances, the strategy applied to each decision, such as the speed-accuracy trade-off, ought to depend on the accuracy of the previous decisions. However, as the accuracy of each decision is often unknown to the decision maker, we hypothesized that subjects may carry forward a level of confidence in previous decisions to affect subsequent decisions. Subjects made two perceptual decisions sequentially and were rewarded only if they made both correctly. The speed and accuracy of individual decisions were explained by noisy evidence accumulation to a terminating bound. We found that subjects adjusted their speed-accuracy setting by elevating the termination bound on the second decision in proportion to their confidence in the first. The findings reveal a novel role for confidence and a degree of flexibility, hitherto unknown, in the brain's ability to rapidly and precisely modify the mechanisms that control the termination of a decision.We thank the Wellcome Trust, the Human Frontier Science Program, the Royal Society (Noreen Murray Professorship in Neurobiology to D.M.W.), Howard Hughes Medical Institute, National Eye Institute grant EY11378 to M.N.S., a Sloan Research Fellowship to R.K., and Simons Collaboration on the Global Brain grant 323439 to R.K
Progenitor cell dynamics in the newt telencephalon during homeostasis and neuronal regeneration
Acknowledgments: We would like to thank E. Andersson and U. Lendahl for providing reagents and for helpful discussions. This work was supported by grants from AFA Insurances, Cancerfonden, Swedish Research Council, and European Research Council to A.S. M.K. was supported by a HFSPO postdoc fellowship.Peer reviewedPublisher PD
Investigating Yang-Mills theory and Confinement as a function of the spatial volume
We study the volume dependence of electric flux energies for SU(2) gauge
theory with twisted boundary conditions. The curves interpolate smoothly
between the perturbative semiclassicalresults and the Confinement regime. On
the basis of our results, we propose that the Confinement property might be
caused by a class of non-dilute multi-instanton configurations.Comment: Postscript - paper.ps and sig_lt3c.eps (Fig 1). 25 pages of text and
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An indirect defence trait mediated through egg-induced maize volatiles from neighbouring plants
Attack of plants by herbivorous arthropods may result in considerable changes to the plantâs
chemical phenotype with respect to emission of herbivore-induced plant volatiles (HIPVs).
These HIPVs have been shown to act as repellents to the attacking insects as well as
attractants for the insects antagonistic to these herbivores. Plants can also respond to HIPV
signals from other plants that warn them of impending attack. Recent investigations have
shown that certain maize varieties are able to emit volatiles following stemborer egg deposition.
These volatiles attract the herbivoreâs parasitoids and directly deter further oviposition.
However, it was not known whether these oviposition-induced maize (Zea mays, L.) volatiles
can mediate chemical phenotypic changes in neighbouring unattacked maize plants.
Therefore, this study sought to investigate the effect of oviposition-induced maize volatiles
on intact neighbouring maize plants in âNyamulaâ, a landrace known to respond to oviposition,
and a standard commercial hybrid, HB515, that did not. Headspace volatile samples
were collected from maize plants exposed to Chilo partellus (Swinhoe) (Lepidoptera: Crambidae)
egg deposition and unoviposited neighbouring plants as well as from control plants
kept away from the volatile emitting ones. Behavioural bioassays were carried out in a fourarm
olfactometer using egg (Trichogramma bournieri Pintureau & Babault (Hymenoptera:
Trichogrammatidae)) and larval (Cotesia sesamiae Cameron (Hymenoptera: Braconidae))
parasitoids. Coupled Gas Chromatography-Mass Spectrometry (GC-MS) was used for volatile
analysis. For the âNyamulaâ landrace, GC-MS analysis revealed HIPV production not
only in the oviposited plants but also in neighbouring plants not exposed to insect eggs.
Higher amounts of EAG-active biogenic volatiles such as (E)-4,8-dimethyl-1,3,7-nonatriene
were emitted from these plants compared to control plants. Subsequent behavioural assays
with female T. bournieri and C. sesamiae parasitic wasps indicated that these parasitoids
preferred volatiles from oviposited and neighbouring landrace plants compared to those
from the control plants. This effect was absent in the standard commercial hybrid we tested.
There was no HIPV induction and no difference in parasitoid attraction in neighbouring and
control hybrid maize plants. These results show plant-plant signalling: âNyamulaâ maize plants emitting oviposition-induced volatiles attractive to the herbivoreâs natural enemies
can induce this indirect defence trait in conspecific neighbouring undamaged maize plants.
Maize plants growing in a field may thus benefit from this indirect defence through airborne
signalling which may enhance the fitness of the volatile-emitting plant by increasing predation
pressure on herbivores
Extinctions and Correlations for Uniformly Discrete Point Processes with Pure Point Dynamical Spectra
The paper investigates how correlations can completely specify a uniformly
discrete point process. The setting is that of uniformly discrete point sets in
real space for which the corresponding dynamical hull is ergodic. The first
result is that all of the essential physical information in such a system is
derivable from its -point correlations, . If the system is
pure point diffractive an upper bound on the number of correlations required
can be derived from the cycle structure of a graph formed from the dynamical
and Bragg spectra. In particular, if the diffraction has no extinctions, then
the 2 and 3 point correlations contain all the relevant information.Comment: 16 page
Selective and mild fractionation of microalgal proteins and pigments using aqueous two-phase systems
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