240 research outputs found
Diet Shapes Mortality Response to Trauma in Old Tephritid Fruit Flies.
Despite the importance of trauma in healthspan and lifespan in humans as well as in non-human species, with one important exception the literature in both gerontology and ecology contains virtually no experimental demographic studies concerned with trauma in any species. We used dietary manipulation [full diet (F) versus sugar-only (S)] to produce four levels of frailty in 55-day old tephritid fruit flies (Anastrepha ludens) that were then subject to the trauma of cage transfer stress (n = 900/sex in each of the 4 treatments). The key results included the following: (1) there is a trauma effect caused by the transfer that depends on previous diet before transfer, new diet after transfer and gender of the fly; (2) males are more vulnerable than females; (3) if initial diet was F, flies are relatively immune against the trauma, and the subsequent diet (F or S) does not matter; (4) however if initial diet was S, then the effect of the trauma depends largely on the diet after the transfer; (5) flies transferred from S to F diets do very well in terms of remaining longevity (i.e. greatest remaining longevity), while flies transferred from S to S diet do poorly (i.e. shortest remaining longevity). We discuss both the strengths and weaknesses of this study and implications of the results
Oscillation Results for Second-Order Nonlinear Damped Dynamic Equations on Time Scales
This paper is concerned with second-order nonlinear damped dynamic equations on time
scales of the following more general form (p(t)k1(x(t),xΔ(t)))Δ+r(t)k2(x(t),xΔ(t))xΔ(t)+f(t,x(σ(t)))=0. New oscillation results are given to handle some cases not covered by known criteria. An illustrative
example is also presented
Kamenev-Type Oscillation Criteria of Second-Order Nonlinear Dynamic Equations on Time Scales
Using functions from some function classes and a generalized Riccati technique, we establish
Kamenev-type oscillation criteria for second-order nonlinear dynamic equations on time scales of the
form (p(t)ψ(x(t))k∘xΔ(t))Δ+f(t,x(σ(t)))=0. Two examples are included to show the significance of the results
An improved kinetic model for the acetone-butanol-ethanol pathway of Clostridium acetobutylicum and model-based perturbation analysis
Bayesian Generational Population-Based Training
Reinforcement learning (RL) offers the potential for training generally
capable agents that can interact autonomously in the real world. However, one
key limitation is the brittleness of RL algorithms to core hyperparameters and
network architecture choice. Furthermore, non-stationarities such as evolving
training data and increased agent complexity mean that different
hyperparameters and architectures may be optimal at different points of
training. This motivates AutoRL, a class of methods seeking to automate these
design choices. One prominent class of AutoRL methods is Population-Based
Training (PBT), which have led to impressive performance in several large scale
settings. In this paper, we introduce two new innovations in PBT-style methods.
First, we employ trust-region based Bayesian Optimization, enabling full
coverage of the high-dimensional mixed hyperparameter search space. Second, we
show that using a generational approach, we can also learn both architectures
and hyperparameters jointly on-the-fly in a single training run. Leveraging the
new highly parallelizable Brax physics engine, we show that these innovations
lead to large performance gains, significantly outperforming the tuned baseline
while learning entire configurations on the fly. Code is available at
https://github.com/xingchenwan/bgpbt.Comment: AutoML Conference 2022. 10 pages, 4 figure, 3 tables (28 pages, 10
figures, 7 tables including references and appendices
Multi-omics profiling highlights lipid metabolism alterations in pigs fed low-dose antibiotics
Nuclear-targeted EGF receptor enhances proliferation and migration of human anaplastic thyroid cancer cells
Introduction: Epidermal growth factor (EGF) has various important physiological functions, which it exerts by binding to the epidermal growth factor receptor (EGFR). Reports show that EGF expression is strongly correlated with the occurrence and development of many types of tumour. To date, however, the relationship between EGF/EGFR and the occurrence and development of thyroid carcinoma remains unclear.
Material and methods: In the current study, we investigated this phenomenon using human anaplastic thyroid carcinoma cell lines (SUN-80).
Results: The results indicated that EGF triggered the EGFR-mediated intracellular signalling pathway, including signal transducers and activators of transcription 1/3/5 (STAT1/3/5) and protein kinase B (AKT) in a time- and dose-dependent manner. In addition, results from EGF-induced EGFR internalization and co-localization analyses showed that clathrin, Rab5/7, and EEA1 play critical roles in the intracellular trafficking of EGF/EGFR. Interestingly, EGF triggered EGFR translocation into the nucleus, while nuclear-localized EGFR affected cell cycle distribution, thereby significantly promoting the ration of S phase. Overall, these findings indicated that nuclear EGFR exerts biological activity and physiological functions, including changing cell cycle, which in turn promotes proliferation and migration of SUN-80 cells.
Conclusion: These findings lay a foundation for further explorations seeking to understand the biological effects of the EGF/EGFR system on the occurrence and development of thyroid cancer
Inter-correlated gut microbiota and SCFAs changes upon antibiotics exposure links with rapid body-mass gain in weaned piglet model
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