Survival and movement patterns of central California coast native steelhead trout (Oncorhynchus mykiss) in the Napa River

Drawing on acoustic telemetry this study identifies and describes local and regional scale survival and movement patterns of Central California Coast steelhead (Oncorhynchus mykiss), including their potential utilization of newly restored tidal marsh habitats in the Napa River system. Between April 8th and May 5th of 2010, 20 steelhead smolts ranging in fork length from 164 to 305 mm were collected, tagged with acoustic transmitters, and released in the upper Napa River (above tidal influence). We found no effect of release date (P?<?0.001) or size (P?<?0.005) on survival estimates based on model likelihoods. Cumulative survival from smolt release location to the Golden Gate Bridge over approximately 77 river kilometers (RKM) was 0.60 (SE?=?0.16). Reach-specific survival was lowest in the initial 30 km reach (0.70 SE?=?0.1). Survival was higher in San Pablo Bay (0.89 SE?=?0.1) and San Francisco Bay (0.96 SE?=?0.2). Sixty percent of the fish that entered the ocean were detected on a line of acoustic monitors at Point Reyes approximately 60 km north of the Golden Gate. Average movement rates of smolts were highest in San Pablo Bay (36.6 km?d^-1 SE?=?3.3) and San Francisco Bay (28.9 km?d^-1 SE?=?6.6). Smolts migrated more slowly in the river (9.0 km?d^-1 SE?=?0.9) and ocean (4.1 km?d^-1 SE?=?1.2). However, smolt movement rates in the river were dependent on location. Average movement rates of smolts were greatest shortly before their exit from the Napa River (83 km?d^-1 SE?=?13.2). Fish were not detected within the recently reconnected former salt production ponds (North, Central, and South units) adjacent to the Napa River. Based on the detection patterns of fish throughout the study area, it appears that most fish were moving at relatively high rates and were not exploring off-channel habitat.     

Insight into Prolonged Cycling Life of 4 V All-Solid-State Polymer Batteries by a High-Voltage Stable Binder

Polyethylene oxide (PEO) based solid polymer electrolytes (SPEs) are incompatible with the 4 V class cathodes such as LiCoO₂ due to the limited electrochemical oxidation window of PEO. Herein, a number of binders including commonly used binders PEO, polyvinylidene fluoride (PVDF), and carboxyl-rich polymer (CRP) binders such as sodium alginate (Na-alginate) and sodium carboxymethyl cellulose, are studied for application in the 4 V class all-solid-state polymer batteries (ASSPBs). The results show ASSPBs with CRP binders exhibit superior cycling performance up to 1000 cycles (60% capacity retention, almost 10 times higher than those with PEO and PVDF binders). Synchrotron-based X-ray absorption spectroscopy (XAS), morphology studies and density functional theory studies indicate that, with their carboxyl groups, CRPs can strongly bind the electrode materials together, and work as coating materials to protect the cathode/SPE interface. Cyclic voltammetry studies indicate that CRP binders are more stable at high voltage compared to PEO and PVDF. The stability under high voltage and the coating property of CRP binders contribute to stable cathode/SPE interfaces as disclosed by the X-ray photoelectron spectroscopy and Co L-edge XAS results, enabling long cycling life, high performance 4 V class ASSPBs.     

Exometabolome profiling reveals activation of the carnitine buffering pathway in fed-batch cultures of CHO cells co-fed with glucose and lactic acid

Adjustments to CHO cell physiology were recently observed during implementation of a Raman spectroscopy-based glucose and lactate control strategy. To further understand how these cells, under monoclonal antibody (mAb) production conditions, utilized the extra lactic acid fed, we performed a comprehensive semi-quantitative and time-dependent analysis of the exometabolome. This study focused on the CHO cell's metabolic shift from the fifth day of culture. We compared relative levels of extracellular metabolites in the absence or presence of a 2 g/L lactic acid setpoint while glucose was kept at 4 g/L. Our hypothesis is that extra lactic acid would supply more pyruvate, favoring oxidative phosphorylation. We subsequentially uncovered several carnitine derivatives as biomarkers of the simultaneous activation of TCA anaplerotic pathways as well as a carbon-buffering pathway. CHO cells exhibited a balance between intermediates from (i) amino acid catabolism, (ii) fatty acid β-oxidation, and (iii) pyruvate from glycolysis and lactic acid; and the secretion of their intermediate carnitine derivatives. In addition, 3-hydroxy-methyl-glutaric acid (HMG) and mevalonate syntheses were found as biomarkers of alternative acyl group removal. Together, under a limited capacity to assimilate the surplus of acyl-CoA groups as well as an ability to maintain the acyl-CoA: free CoA ratio for proper and continuous functioning of the TCA cycle, CHO cells activate the carnitine-buffering system, HMG, and mevalonate pathways.     

Analyzing Single-Molecule Time Series via Nonparametric Bayesian Inference

The ability to measure the properties of proteins at the single-molecule level offers an unparalleled glimpse into biological systems at the molecular scale. The interpretation of single-molecule time series has often been rooted in statistical mechanics and the theory of Markov processes. While existing analysis methods have been useful, they are not without significant limitations including problems of model selection and parameter nonidentifiability. To address these challenges, we introduce the use of nonparametric Bayesian inference for the analysis of single-molecule time series. These methods provide a flexible way to extract structure from data instead of assuming models beforehand. We demonstrate these methods with applications to several diverse settings in single-molecule biophysics. This approach provides a well-constrained and rigorously grounded method for determining the number of biophysical states underlying single-molecule data.     

Cladogenesis and replacement in the fossil record of Microsyopidae (?Primates) from the southern Bighorn Basin,Wyoming

The early Eocene of the southern Bighorn Basin, Wyoming, is notable for its nearly continuous record of mammalian fossils. Microsyopinae (?Primates) is one of several lineages that shows evidence of evolutionary change associated with an interval referred to as Biohorizon A. Arctodontomys wilsoni is replaced by a larger species, Arctodontomys nuptus, during the biohorizon interval in what is likely an immigration/emigration or immigration/local extinction event. The latter is then superseded by Microsyops angustidens after the end of the Biohorizon A interval. Although this pattern has been understood for some time, denser sampling has led to the identification of a specimen intermediate in morphology between A. nuptus and M. angustidens, located stratigraphically as the latter is appearing. Because specimens of A. nuptus have been recovered approximately 60 m above the appearance of M. angustidens, it is clear that A. nuptus did not suffer pseudoextinction. Instead, evidence suggests that M. angustidens branched off from a population of A. nuptus, but the latter species persisted. This represents possible evidence of cladogenesis, which has rarely been directly documented in the fossil record. The improved understanding of both evolutionary transitions with better sampling highlights the problem of interpreting gaps in the fossil record as punctuations.