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Plankton ecologists ultimately focus on forecasting, both applied and environmental outcomes. We review how appreciating planktonic ciliates has become central to these predictions. We explore the 350‐year‐old canon on planktonic ciliates and examine its steady progression, which has been punctuated by conceptual insights and technological breakthroughs. By reflecting on this process, we offer suggestions as to where future leaps are needed, with an emphasis on predicting outcomes of global warming. We conclude that in terms of climate change research: (i) climatic hotspots (e.g. polar oceans) require attention; (ii) simply adding ciliate measurements to zooplankton/phytoplankton‐based sampling programs is inappropriate; (iii) elucidating the rare biosphere's functional ecology requires culture‐independent genetic methods; (iv) evaluating genetic adaptation (microevolution) and population composition shifts is required; (v) contrasting marine and freshwaters needs attention; (vi) mixotrophy needs attention; (vii) laboratory and field studies must couple automated measurements and molecular assessment of functional gene expression; (viii) ciliate trophic diversity requires appreciation; and (ix) marrying gene expression and function, coupled with climate change scenarios is needed. In short, continued academic efforts and financial support are essential to achieve the above; these will lead to understanding how ciliates will respond to climate change, providing tools for forecasting. [ABSTRACT FROM AUTHOR]

We planned to develop predator-prey models using Paramecium and yeast, but they have not been empirically examined since work by Gause in the 1930s. Therefore, we evaluated if Paramecium aurelia ingests and grows on eight yeasts. Recognising that it ingested yeasts but could not grow, we assessed if it might grow on other yeasts, by empirically parameterising a predator-prey model that relies on ingestion, not growth. Simulations were compared to P. aurelia-yeast time-series data, from Gause. We hypothesised that if the model simulated predator-prey dynamics that mimicked the original data, then possibly P. aurelia could grow on yeast; simulations did not mimic the original data. Reviewing works by Gause exposed two issues: experiments were undoubtedly contaminated with bacteria, allowing growth on bacteria, not yeast; and the population cycle data cannot be considered a self-sustaining time series, as they were manipulated by adding yeast and ciliates. We conclude that past and future work should not rely on this system, for either empirical or theoretical evaluations. Finally, although we show that P. aurelia, P. caudatum, Euplotes patella, and Blepharisma sp. cannot grow on yeast, Tetrahymena pyriformis and Colpidium striatum can; these may provide models to explore predator-prey dynamics. [ABSTRACT FROM AUTHOR]

ABSTRACT The type I procollagen carboxyterminal( C-)propeptides are crucial in directing correct assembly of the procollagen heterotrimers. Defects in these domains have anecdotally been reported in patients with Osteogenesis Imperfecta ( OI) and few genotype-phenotype correlations have been described. To gain insight in the functional consequences of C-propeptide defects, we performed a systematic review of clinical, molecular, and biochemical findings in all patients in whom we identified a type I procollagen C-propeptide defect, and compared this with literature data. We report 30 unique type I procollagen C-propeptide variants, 24 of which are novel. The outcome of COL1A1 nonsense and frameshift variants depends on the location of the premature termination codon. Those located prior to 50-55 nucleotides upstream of the most 3' exon-exon junction lead to nonsense-mediated m RNA decay ( NMD) and cause mild OI. Those located beyond this boundary escape NMD, generally lead to production of stable, overmodified procollagen chains, which may partly be retained intracellularly, and are usually associated with severe-to-lethal OI. Proα1(I)- C-propeptide defects that permit chain association result in more severe phenotypes than those inhibiting chain association. We demonstrate that the crystal structure of the proα1(III)- C-propeptide is a reliable tool to predict phenotypic severity for most COL1A1- C-propeptide missense variants, whereas for COL1A2-C-propeptide variants, the phenotypic outcome is milder than predicted. [ABSTRACT FROM AUTHOR]

Questions How do semi-deciduous and evergreen shrubs exploit environmental resources during summer drought? What is the contribution of the understorey shrubby layer to ecosystem carbon assimilation? To what extent are carbon balance and transpiration impacted by a rain pulse? Location Cork oak open woodland in the Mediterranean region. Methods We used closed dynamic light and dark chambers to measure gas exchange ( CO2 and H2 O) in the dominant shrub understorey species Cistus salviifolius, Cistus crispus (semi-deciduous) and Ulex airensis (evergreen), together with plant physiological and morphological measurements during summer drought and autumn recovery. A hyperbolic light response model constrained by vapour pressure deficits was fitted for up-scaling shrub photosynthesis to the ecosystem level. The data were compared, on a daily and daytime basis, with gross primary productivity estimates from ecosystem eddy-covariance flux measurements. Results The onset of summer drought led to a significant leaf area reduction in semi-deciduous species. A general decrease in photosynthesis in all species was observed, while evapotranspiration and above-ground respiration fluxes contrasted among species during summer progression and autumn recovery. The shallow-rooted C. salviifolius was able to use light more efficiently than the other two species, although with poor stomatal control over water loss and consistently higher above-ground respiration rates, leading to lower water and carbon use efficiencies when compared with C. crispus. The deep-rooted shrub U. airensis maintained higher leaf water potentials and very low photosynthetic rates while decreasing transpiration rates throughout the summer drought. A summer rain pulse showed that shallow-rooted shrubs use water in an opportunistic way, with immediate leaf rehydration and concomitant photosynthesis increments. Conversely, deep-rooted shrubs ( U. airensis) were unresponsive, only recovering photosynthesis with high soil water content. An opportunistic growth response may be disadvantageous to shallow-rooted shrubs in a future climate with extended dry summers and higher probability of rain pulse events. The prominent increase in transpiration rates and plant respiration costs observed during the dry conditions that followed the rain pulse, led to a reduced plant ability to recover after autumn rains. Conclusions The shrubs that naturaly colonized this montado understorey showed contrasting strategies to overcome summer drought, suggesting an efficient mosaic exploitation of seasonal environmental resources. The contribution of these shrubs to total ecosystem CO2 uptake during summer and autumn recovery was 17%. This high contribution implies that shrub density management decisions should consider a carbon balance perspective. [ABSTRACT FROM AUTHOR]

Objective: To characterize the background and outcomes of tonsillectomy malpractice claims. Methods: Review of 69 New York State insurance claims (Part I) and 87 national court trials (Part II) alleging injury after tonsillectomy. Results: Part I. New York State insurance cases were most commonly discontinued (44%) or settled (42%) before trial. Compensations with a settlement or verdict were made in 48 percent of cases. Part II. Death or major injury occurred in 52 percent of insurance cases, with a mean award of $403,656 being made to plaintiffs. Of cases reaching trial, 60 percent of plaintiffs were compensated. Awards against anesthesiologists were more frequent and higher than against surgeons ($5 million vs $839,650). Death or major injury occurred in 52 percent of court cases, resulting in mean indemnity of $3.8 million. Most cases of death or major injury were attributable to airway complications. Conclusions: Approximately half of both New York state claims and court cases involved death or devastating morbidity, mostly related to airway complications, resulting in large awards. Tonsillectomy is a source of uncommon but potentially high-dollar–value litigation exposure to the surgeon, often attributable to non-surgical complications. [Copyright &y& Elsevier]

This study evaluates the role of protozoa in larval fish feeding by describing protozoa in larval fish diets and testing the hypothesis that, in the Irish Sea, larval fish feed on protozoan prey at rates that potentially sustain their food requirements. Gut contents of 11 taxonomic groups of larval fish were examined, and protist prey occurred in the diet of all of them. Protozoan prey were identified, which provided an insight into their trophic role. Most of the protozoan prey were autotrophic or mixotrophic. In general, larval fish diets were constant over the spring/summer period, regardless of prey availability in the field and the composition of larval fish assemblage (taxonomy and size). A laboratory experiment on ingestion rates of flounder larvae as a function of ciliates concentration was conducted. Combined laboratory and field data showed that, in the Irish Sea, it is unlikely that ciliates are often the primary food source of flounder larvae, and, by implication, other larval fish as well. However, ciliates and other protozoa could be a substantial component of the larval fish diet, and they may potentially prevent food limitation. [ABSTRACT FROM PUBLISHER]

Examines the ability of fresh and aged non-AlphaBeta component of Alzheimer's disease amyloid (NAC) and fragments thereof to inhibit the reduction of the redox dye 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide. Correlation to the formation of beta-sheet structure and fibrils; Peptide synthesis; Cytotoxicity assay.

Reports on the operation of a type of fluorescence lifetime imaging camera based on the time-correlated single-photon counting technique. Use of the application-specific integrated circuit (ASIC) for the field of fluorescence; Spatial distribution of fluorescence lifetime that contours through a strongly self-absorbing sample.

A new method for determining the donor-acceptor distribution function in fluorescence resonance energy transfer (FRET) systems is presented. The approach is based on time-resolved fluorescence experiments with nanosecond resolution. Potential applications of this method include: determination of the morphology of porous materials (e.g., polymers, sol-gels, resins, etc.), monitoring processes occurring on the nanometer scale including biomolecules labeled with the donor/acceptor species, and FRET sensors based on competitive binding. In this paper a theoretical derivation of the method is presented and the method is tested in a series of numerical simulations. The experimental conditions regarding this approach are discussed and its applicability to real measurement systems is demonstrated. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]