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Abstract: Precipitation in fall and winter is important to recharge aquifers in Northern California and the Pacific Northwestern United States, causing the baseflow in rivers ascend during the time when Chinook salmon (Oncorhynchus tshawytscha) construct redds. Herein, we evaluate the availability of spawning habitats under a constant streamflow common in regulated rivers against ascending baseflows patterned from free‐flowing rivers. A binomial logistic regression model was applied to predict the suitability of redd locations based on physical characteristics. Next, two‐dimensional hydrodynamic habitat models were developed at two locations representing a broad range of channel forms common in large rivers. Hydrodynamic and habitat models were leveraged together to simulate the quality, amount, and spatial distribution of spawning habitat at a series of individual flow rates, as well as the combined effect of those flow rates through a spawning season with ascending baseflows. Ascending baseflows increased the abundance of spawning habitat over individual streamflows at a site where the river channel is confined by levee‐like features. However, improvements were greater at an unconfined site that facilitated lateral connectivity and greater expansion of wetted channel area as streamflows increased. Ascending baseflows provided spatial separation in preferred habitats over a spawning season, which may reduce the risk of superimposition among runs or among species. Ascending baseflows provided a benefit across the range of hydrologic regimes in a 100‐year gauge record ranging from 20% to 122% improvements in habitat area over low streamflows that are currently used to manage for spawning habitat. Although replicating natural flow regimes in managed systems can be impossible or impractical, these results demonstrate that incorporating elements of the natural flow regime like ascending baseflows can benefit the restoration and conservation of riverine species. [ABSTRACT FROM AUTHOR]

Two-dimensional hydrodynamic models are increasingly common in riverine research and management. However, input data are not standardized among studies, and assessments of model performance are uncommon, which hinder interpretation of model results and comparisons among studies. Herein, we describe a framework for two-dimensional hydrodynamic model input data collection, model calibration and validation to evaluate model predictions. We present a logical process for the validation of depth and velocity that recognizes the inherent spatial uncertainty in the field measurements and modelling results. The hydrodynamic model we present as an example shows agreement between predicted and observed water surface elevation, area of inundation and spatial distributions of depth and velocity at calibration and independent validation discharges. If this model development and assessment framework was adopted by others, it would allow comparison between studies and provide a foundation for establishing model performance standards. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Phylogenetic structure of four Lampetra species from the Pacific drainage of North America (western brook lamprey Lampetra richardsoni, Pacific brook lamprey Lampetra pacifica, river lamprey Lampetra ayresii and Kern brook lamprey Lampetra hubbsi) and unidentified Lampetra specimens (referred to as Lampetra sp.) from 36 locations was estimated using the mitochondrial cytochrome b gene. Maximum parsimony and Bayesian inferences did not correspond with any taxonomic scheme proposed to date. Rather, although L. richardsoni (from Alaska to California) and L. ayresii (from British Columbia to California) together constituted a well-supported clade distinct from several genetically divergent Lampetra populations in Oregon and California, these two species were not reciprocally monophyletic. The genetically divergent populations included L. pacifica (from the Columbia River basin) and L. hubbsi (from the Kern River basin) and four Lampetra sp. populations in Oregon (Siuslaw River and Fourmile Creek) and California (Kelsey and Mark West Creeks). These four Lampetra sp. populations showed genetic divergence between 2·3 and 5·7% from any known species (and up to 8·0% from each other), and may represent morphologically cryptic and thus previously undescribed species. A fifth population (from Paynes Creek, California) may represent a range extension of L. hubbsi into the Upper Sacramento River. [ABSTRACT FROM AUTHOR]

Objective To establish reference values for activated coagulation time (ACT) in normal cats and dogs, by visual assessment of clot formation using the MAX-ACTTM tube. Subjects We recruited 43 cats and 50 dogs for the study; 11 cats and 4 dogs were excluded from the statistical analysis because of abnormalities on clinical examination or laboratory testing including anaemia, prolonged prothrombin time (PT) or activated partial thromboplastin time (APTT), or insufficient plasma volume for comprehensive laboratory coagulation testing. Procedure Blood samples were collected via direct venipuncture for MAX-ACT, packed cell volume/total solids, manual platelet estimation and PT/APTT measurement. Blood (0.5 mL) was mixed gently in the MAX-ACT tube at 37°C for 30 s, then assessed for clot formation every 5 to 10 s by tipping the tube gently on its side and monitoring for magnet movement. The endpoint was defined as the magnet lodging in the clot. The technique was tested with 10 dogs by collecting two blood samples from the same needle insertion and running a MAX-ACT on each simultaneously. Results In normal cats the mean MAX-ACT was 66 s (range 55–85 s). In normal dogs the mean was 71 s (range 55–80 s). There was no statistical difference between the first and second samples collected from the same needle insertion. Conclusions and Clinical Relevance In both cats and dogs, a MAX-ACT result >85 s should be considered abnormal and further coagulation testing should be performed. Additionally, failure to discard the first few drops of the sample does not appear to significantly affect results. [ABSTRACT FROM AUTHOR]

Mitochondrial DNA variation among 1246 individuals of Pacific lamprey ( Entosphenus tridentatus) from 81 populations spanning 2600 km from the Skeena River, British Columbia, to the Ventura River, California, was surveyed using five restriction enzymes. A total of 29 composite haplotypes was detected in two gene fragments (ND2 and ND5). The three most common haplotypes, occurring in 91% of all samples, were present at similar frequencies in all regions. Samples were divided into six biogeographic regions based on sample distribution and geographical landmarks to assess geographic genetic structure. Analysis of molecular variance indicated that 99% of the genetic variation was explained by variability within drainages. The lack of geographical population structure is likely related to a life-history pattern that includes a prolonged larval freshwater stage, migration to oceanic feeding and return to fresh water to spawn. The lack of strong natal homing apparently promotes gene flow among drainages and regions. [ABSTRACT FROM AUTHOR]

We developed five polymerase chain reaction-based markers that detect variation in the mitochondrial genome of the Pacific lamprey, Entosphenus tridentatus, across most of its range. Two gene fragments (ND2 and ND5) were amplified and digested with three and two restriction enzymes, respectively, detecting sequence variation at 18 sites (ND2 = 13; ND5 = 5) and yielding 29 composite haplotypes among 1246 lampreys. These sequence-based markers will be useful in a range of phylogeographical and population genetic studies. [ABSTRACT FROM AUTHOR]

Abstract: More reliable methods are needed to identify children at risk for poor outcomes following liver transplantation. The Pediatric Risk of Mortality (PRISM) Score is a physiology-based scoring system used to quantify risk of mortality in pediatric intensive care unit (ICU) populations. We evaluated the PRISM Score as a predictor of outcomes including survival in the pediatric liver transplant (LT) population. We retrospectively reviewed the records of 67 consecutive LTs performed between August 1997 and February 2000 at an urban, tertiary children's hospital in Chicago, IL, USA. Four PRISM Scores were calculated to determine which periods were most meaningful. A Classic PRISM Score was calculated during first 24 h of ICU admission, and three PRISM Scores were timed with the patient's transplant: a pre-LT PRISM Score (24 h prior to transplant whether in ICU or not), a 24-h post-LT PRISM Score and a 48-h post-LT PRISM Score. These PRISM Scores and other predictors including transplant number, UNOS status and PELD Score were compared with outcomes including survival using univariate methods. The pre-LT, the 24- and the 48-h PRISM Score were associated with the post-LT number of ventilated days (p < 0.05), ICU days (p < 0.05) and with 1-yr survival (p < 0.04). The PRISM Scores were not related to the post-LT hospital length of stay (LOS) or to 1-yr re-transplantation. The PELD Score correlated with the post-LT hospital LOS, but was not associated with mortality or with the ICU LOS. A patient's UNOS status and Classic PRISM Score were not associated with any of the outcomes measured. PRISM Scores are valid predictors of outcome including survival in pediatric LT recipients. These findings help to demonstrate the importance in this population of a patient's general physiologic condition and its influence on the overall hospital course and survival. [ABSTRACT FROM AUTHOR]

Presents an article which challenges the false opposition between public and private spheres that is often imposed upon our historical understanding of the Old Regime in France. Analysis; Examination; Conclusion.

SUMMARY A miniature penetrometer which measures soil strength in a vertical section across a drill line is described. It has a cone diameter of 3.6 mm and a range and resolution of 0-5000 and 5.4 kPa respectively. Data are recorded directly on to a portable digital tape logger which interfaces directly with a microcomputer for data analysis. The use of a horizontal reference height, rather than the soil, enables measurement of the soil surface relief. Results are presented showing the mean soil strength in a vertical section (200 mm wide by 130 mm deep) in drill lines in autumn and spring cultivated soil, with a horizontal and vertical resolution of 10 and 3 mm respectively. [ABSTRACT FROM AUTHOR]

SUMMARY Secondary cultivations for the spring-sowing of vegetables are often delayed because they cannot be carried out until the soil to the depth of cultivation has dried to the plastic limit (i.e. it crumbles rather than smears). It is suggested that doing secondary cultivations in the autumn, and then drilling in the spring without further cultivation, would be less liable to delays because only the soil down to the depth of drilling need dry below the plastic limit. Simple models are derived to calculate soil water contents from weather data. They show that between 1960 and 1981 the 0-120 mm layer (representing a typical cultivation depth) dried beyond the plastic limit for an average of 36% of the days between 14 February and 9 May, compared with 68% for the 0-30 mm layer (proposed system). Wheel sinkage, bulk density and cone resistance measurements showed that a tractor would cause excessive compaction when only the surface 30 mm was drier than the plastic limit, but this could be minimized by using a low ground pressure vehicle. [ABSTRACT FROM AUTHOR]

Presents a study which identifies the factors that determine share prices in relation to ditch companies in the United States. Information on ditch companies; Reference to the South Platte River Basin in Colorado; Determinants of ditch company share prices; Variables used in the statistical study; Details on an econometric model; Results of the study; Conclusion reached based on these results.

Most of the requirements of roots for oxygen were met by oxygen from the air entering the leaves and travelling through the plants to the roots in oxygen-free media. The amount of oxygen supplied in this way decreased proportionately with rise in oxygen partial pressure at the root surface. Although roots offered a considerable barrier to the passage of oxygen out of them, experiments in which transport from the aerial parts was prevented indicated that the roots could obtain almost all the oxygen they required from the surrounding media provided the oxygen partial pressure at the root surface exceeded the low value of 0.05 atmospheres. These results were obtained by means of a new experimental technique which enabled the effect of oxygen partial pressure at the root surfaces on oxygen uptake and root elongation to be studied. It was based on circulating a small volume of nutrient solution around roots in a gas-free enclosed system sufficiently rapidly for the partial pressure in the solution to be almost the same as at the root surfaces. [ABSTRACT FROM AUTHOR]

The micro electrode of Evans and Naylor was modified to permit measurements of oxygen concentration in soil and was used to determine the distribution of oxygen in ( a) agar which contained yeast and glucose and served as a model of a respiring water-saturated soil; ( b) saturated spherical soil aggregates; ( c) partly saturated columns of fine soil crumbs. Measurements in (a) and ( b) but not in ( c) agreed closely with predictions by diffusion theory. The disagreement appeared to result from water being unevenly distributed in the columns. [ABSTRACT FROM AUTHOR]

Review: 60 refs. [ABSTRACT FROM AUTHOR]