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High-speed wide-field fluorescence microscopy has the potential to capture biological processes with exceptional spatiotemporal resolution. However, conventional cameras suffer from low signal-to-noise ratio at high frame rates, limiting their ability to detect faint fluorescent events. Here, we introduce an image sensor where each pixel has individually programmable sampling speed and phase, so that pixels can be arranged to simultaneously sample at high speed with a high signal-to-noise ratio. In high-speed voltage imaging experiments, our image sensor significantly increases the output signal-to-noise ratio compared to a low-noise scientific CMOS camera (~2–3 folds). This signal-tonoise ratio gain enables the detection of weak neuronal action potentials and subthreshold activities missed by the standard scientific CMOS cameras. Our camera with flexible pixel exposure configurations offers versatile sampling strategies to improve signal quality in various experimental conditions. [ABSTRACT FROM AUTHOR]

Cardiovascular risk has traditionally been defined by modifiable and non-modifiable risk factors, such as tobacco use, hyperlipidemia, and family history. However, chemicals and pollutants may also play a role in cardiovascular disease (CVD) risk. Arsenic is a naturally occurring element that is widely distributed in the Earth's crust. Inorganic arsenic (iAs) has been implicated in the pathogenesis of atherosclerosis, with chronic high-dose exposure to iAs (> 100 µg/L) being linked to CVD; however, whether low-to-moderate dose exposures of iAs (< 100 µg/L) are associated with the development of CVD is unclear. Due to limitations of the existing literature, it is difficult to define a threshold for iAs toxicity. Studies demonstrate that the effect of iAs on CVD is far more complex with influences from several factors, including diet, genetics, metabolism, and traditional risk factors such as hypertension and smoking. In this article, we review the existing data of low-to-moderate dose iAs exposure and its effect on CVD, along with highlighting the potential mechanisms of action. [ABSTRACT FROM AUTHOR]

Background and aims: Host-specific Epichloë spp. are endophytic fungal symbionts of pooid grasses that produce herbivore-deterring alkaloids and alter the host's metabolite and protein profiles. Early observations suggested that Epichloë may have negative allelopathic effects on neighbouring plant species, particularly Trifolium spp. clovers, but subsequent allelopathy experiments produced variable results. We examined two hypotheses: (1) Epichloë strains differ in allelopathic effect, and (2) Epichloë allelopathy negatively affects other plant species. Methods: We performed a greenhouse experiment using root exudates from Lolium perenne L. hosting different E. festucae var. lolii (Latch, M.J. Chr. & Samuels) C.W. Bacon & Schardl strains to compare their allelopathic effects on native legumes and forbs. We then used meta-analysis to examine the evidence to date for allelopathic effects of Epichloë endophytes. Results: We found little difference in effect among E. festucae var. lolii strains and very little evidence for negative allelopathic effects of Epichloë in cool-season grasses across a range of methodologies, target plant species, and response measures. Negative allelopathic effects were detected only for root hair measures, which were from a single study. Positive effects on biomass were found for some experimental subgroups, including legumes. However, the majority of response variables showed no evidence for Epichloë allelopathy. Conclusions: Although there is currently little evidence for negative Epichloë allelopathic effects, our meta-analysis identified several research gaps. Experiments testing the functional belowground effects of Epichloë presence may help to determine its effects on non-host plant performance via plant-soil feedbacks. [ABSTRACT FROM AUTHOR]

Myocardial injury after non-cardiac surgery (MINS) is common. We investigated the incidence and outcomes of MINS, and mechanistic underpinnings using pre-operative whole blood gene expression profiling in a prospective cohort study of individuals undergoing lower extremity revascularization (LER) for peripheral artery disease (PAD). Major adverse cardiovascular and limb events (MACLE) were defined as a composite of death, myocardial infarction, stroke, major lower extremity amputation or reoperation. Among 226 participants undergoing LER, MINS occurred in 53 (23.5%). Patients with MINS had a greater incidence of major adverse cardiovascular events (49.1% vs. 22.0%, adjusted HR 1.87, 95% CI 1.07–3.26) and MACLE (67.9% vs. 44.5%; adjusted HR 1.66, 95% CI 1.08–2.55) at median 20-month follow-up. Pre-operative whole blood transcriptome profiling of a nested matched MINS case–control cohort (n = 41) identified upregulation of pathways related to platelet alpha granules and coagulation in patients who subsequently developed MINS. Thrombospondin 1 (THBS1) mRNA expression was 60% higher at baseline in patients who later developed MINS, and was independently associated with long-term cardiovascular events in the Duke Catheterization Genetics biorepository cohort. In conclusion, pre-operative THBS1 mRNA expression is higher in patients who subsequently develop MINS and is associated with incident cardiovascular events. Pathways related to platelet activity and coagulation associated with MINS provide novel insights into mechanisms of myocardial injury. [ABSTRACT FROM AUTHOR]

Strictly vertically transmitted (hereditary) Epichloë spp. fungal endophytes are symbionts with cool-season pooid host grasses. Such endophytes may increase host invasiveness in the non-native, introduced ranges. However, because costs and benefits for the host can vary with the growing conditions, the endophyte may become locally or temporally extinct when costs outweigh benefits. Our long-term field experiment involved the introduction of seven Schedonorus pratensis (meadow fescue) cultivars hosting Epichloë uncinata endophyte, which represent host-grass populations differing in genetic backgrounds and Epichloë infection frequencies, to an unmanaged old field. In the first 6 years, the host grasses persisted but did not become invasive in the plant community, regardless of their endophyte infection frequency. Subsequently, we hypothesized that increasing nutrient availability would decrease endophyte costs and thus increase the host's success and abundance. We fertilized half of the plots for four additional years and re-examined S. pratensis invasiveness. We predicted that increased nutrient availability would increase S. pratensis abundance and E. uncinata frequency and concentration, as well as decrease plant community diversity, relative to unfertilized plots. Fertilization increased endophyte concentrations in three low-endophyte host populations. However, E. uncinata did not enable S. pratensis populations to achieve high abundance or to reduce plant community diversity in the old field, with or without fertilization. Thus, nutrient availabililty and host invasiveness appear to be decoupled in this study system. [ABSTRACT FROM AUTHOR]

Thrombosis is a major concern in respiratory infections. Our aim was to investigate the magnitude and duration of risk for arterial and venous thrombosis following discharge after respiratory infection. Patients with respiratory infections were identified using the United States Nationwide Readmission Database from 2012 to 2014. Patients admitted with asthma or cellulitis served as comparators. Readmissions for acute myocardial infarction (MI) and venous thromboembolism (VTE) were evaluated at 30 to 180 days. The likelihood of a first thrombotic event after discharge was compared with a 30-day period prior to hospitalization. Among 5,271,068 patients discharged after a respiratory infection, 0.56% and 0.78% were readmitted within 30-days with MI and VTE, respectively. Relative to asthma and cellulitis, respiratory infection was associated with a greater age and sex-adjusted hazard of 30-day readmission for MI (adjusted HR [aHR] 1.48 [95% CI 1.42–1.54] vs. asthma; aHR 1.36 [95% CI 1.31–1.41] vs. cellulitis) and VTE (aHR 1.28 [95% CI 1.24–1.33] vs. asthma; aHR 1.26, [95% CI 1.22–1.30] vs. cellulitis). Risks of MI and VTE attenuated over time. In a crossover-cohort analysis, the odds of MI (OR 1.68 [95% CI 1.62–1.73]) and VTE (OR 3.30 [95% 3.19–3.41]) were higher in the 30 days following discharge after respiratory infection than during the 30-day baseline period. Hospitalization for respiratory infection was associated with increased risks of thrombosis that were highest in the first 30-days after discharge and declined over time. [ABSTRACT FROM AUTHOR]

Elevated atmospheric CO2 concentration increases the performance of invasive plants relative to natives when grown in monoculture, but it is unclear how that will affect the relative competitive abilities per se of invasive and native grasses grown together. We tested competitive outcomes for four native and four invasive perennial C3 and C4 grasses under ambient (390 ppm) and elevated (700 or 1000 ppm) CO2 concentrations in the greenhouse with non-limiting water and nutrients. We predicted that elevated CO2 would increase the competitive suppression of native grasses by invasive grasses. To test this, we determined the relative interaction intensity of biomass allocation for natives grown alone vs. those grown in native–invasive species pairs. We also measured photosynthetic traits that contribute to plant invasiveness and may be affected by elevated CO2 concentrations for species pairs in mixture to determine native–invasive relative performance. We found no effect of CO2 for the aboveground biomass and tiller production measures of interaction intensity or for relative performance for most of the measured photosynthetic traits. In competition, the invaders nearly always outperform natives in biomass and tiller production, regardless of CO2 level. The results suggest that increasing CO2 concentration alone has little effect on grass competitive outcomes under controlled conditions. [ABSTRACT FROM AUTHOR]

Chelation therapy, typically used to remove heavy metal toxins, has also been controversially used as a treatment for coronary artery disease. The first Trial to Assess Chelation Therapy (TACT) aimed to provide evidence on chelation therapy's potential for benefit or harm. Although TACT had some significant results, the trial does not provide enough evidence to recommend routine chelation therapy and has limitations. The second TACT was recently funded reigniting a discussion about the value of chelation therapy, its efficacy, and allocation of research resources. Despite limited evidence, patients continue to pursue chelation therapy as a treatment for coronary artery disease. As the medical community has a responsibility to understand all treatments patients pursue, it is important to comprehensively appraise chelation therapy for cardiovascular disease. Understanding the background of heavy metal toxicity, the putative target of chelation therapy, on the cardiovascular system is important to contextualize the role of chelation therapy in cardiovascular disease prevention. We review the clinical evidence of heavy metal toxicity and cardiovascular disease, and available clinical trial data on use of chelation therapy to minimize the cardiovascular burden of heavy metal toxicity. [ABSTRACT FROM AUTHOR]

Robust tools are needed to prioritise the management of invasive non-native species (INNS). Risk assessment is commonly used to prioritise INNS, but fails to take into account the feasibility of management. Risk management provides a structured evaluation of management options, but has received little attention to date. We present a risk management scheme to assess the feasibility of eradicating INNS that can be used, in conjunction with existing risk assessment schemes, to support prioritisation. The Non-Native Risk Management scheme (NNRM) can be applied to any predefined area and any taxa. It uses semi-quantitative response and confidence scores to assess seven key criteria: Effectiveness, Practicality, Cost, Impact, Acceptability, Window of opportunity and Likelihood of re-invasion. Scores are elicited using expert judgement, supported by available evidence, and consensus-building methods. We applied the NNRM to forty-one INNS that threaten Great Britain (GB). Thirty-three experts provided scores, with overall feasibility of eradication assessed as 'very high' (8 species), 'high' (6), 'medium' (8), 'low' (10) and 'very low' (9). The feasibility of eradicating terrestrial species was higher than aquatic species. Lotic freshwater and marine species scored particularly low. Combining risk management and existing risk assessment scores identified six established species as priorities for eradication. A further six species that are not yet established were identified as priorities for eradication on arrival as part of contingency planning. The NNRM is one of the first INNS risk management schemes that can be used with existing risk assessments to prioritise INNS eradication in any area. [ABSTRACT FROM AUTHOR]

Horizon scanning for high-risk invasive non-native species (INNS) is crucial in preparing and implementing measures to prevent introductions, as well as to focus efforts in the control of species already present. We initiated a trans-national horizon-scanning exercise focused on four countries in western Europe: Great Britain, France, Belgium and The Netherlands, which share similar environmental and socio-economic characteristics. We followed a structured four-step approach combining existing knowledge about INNS, with a collaborative identification of priorities for research and management: (1) systematic review of potential INNS of concern, (2) discrimination of INNS into an Alert and Black List depending on their absence or presence in the study area respectively, (3) risk analysis of the Alert List, and (4) expert ranking of species in the Black List. Amongst species not yet present in the four countries (i.e. Alert List), assessors reliably pointed to the Emerald ash-borer ( Agrilus planipennis) and Sosnowski's hogweed ( Heracleum sosnowskyi) as those INNS with the highest risk of invasion and impact. The Japanese knotweed ( Fallopia japonica), Himalayan balsam ( Impatiens glandulifera), zebra mussel ( Dreissena polymorpha) and killer shrimp ( Dikerogammarus villosus) were consistently highlighted as some of the most problematic INNS already present in the study area (i.e. Black List). The advantages of our combined approach include that it is inclusive of all-taxa, prioritizes both established and emerging biological threats across trans-national scales, and considers not only the ecological impact, but also potential direct economic consequences as well as the manageability of invasive species. [ABSTRACT FROM AUTHOR]

Many invasive plants originate as cultivated species. The growing demand for renewable energy has stimulated agricultural production of native and non-native perennial grasses, but little is known about their potential to become invasive outside cultivation, particularly at the early establishment phase. We evaluated effects of propagule pressure and establishment limitations for early establishment of four potential bioenergy grasses in agricultural field margins and forest understory across a 6.3° latitudinal gradient (Ontario, Canada; Illinois and Virginia, USA). We used multiple seed introductions in different years and followed their fate for up to three growing seasons. High interannual variability in establishment indicates that the frequency of propagule introduction is important for invasion outside cultivation. Establishment limitations were stronger in forest than field margins; of 328,800 seeds added, only 1 of 505 persisting seedlings occurred in forest. Removal of competing vegetation had small and variable effects on establishment among sites and species. Unlike previous short-term experiments, our results indicate the potential for the persistence of these bioenergy grasses in both vegetation and seed bank, and highlight the importance of long-term experiments in evaluating invasion risk. [ABSTRACT FROM AUTHOR]

Prioritizing management efforts and funds for invasive species relies upon knowledge of their ecological impacts. Often, however, novel species have unknown effects and can exhibit long time lags before proliferating, making early management decisions difficult. The grasses Miscanthus sinensis, M. sacchariflorus, and their sterile hybrid M. × giganteus have been introduced to North America and elsewhere for horticultural and agricultural purposes, but little is known about their impacts on resident vegetation upon escape from cultivation. We compared the vegetation communities and soil seed bank of paired areas invaded and uninvaded by escaped M. sacchariflorus at ten sites in Ontario, Canada. Invaded plots had very few species other than M. sacchariflorus and had lower plant species abundance, richness, and diversity than did uninvaded plots, and effects were greater on the vegetation than on the seed bank. Invaded plots also had more live and dead standing biomass, taller vegetation, and greater litter biomass, along with decreased light penetration to the soil surface than in uninvaded plots. However, M. sacchariflorus did not produce a germinable seed bank. Our results suggest that the regional spread of M. sacchariflorus is currently limited by a lack of seed production/viability, but its occurrence along disturbance-prone roadways and drainages facilitates its local vegetative spread. The strong negative effects of M. sacchariflorus on the resident plant community should be considered in risk assessments and management planning for this and other Miscanthus species. [ABSTRACT FROM AUTHOR]

The National Lipid Association (NLA) recently released recommendations for the treatment of dyslipidemias. These recommendations have commonalities and differences with those of other major societies with respect to risk assessment, lifestyle therapy, targets of therapy, and the use of non-statin agents. In this review, we compare the basic elements of the guidelines from each major society to provide clinicians with a comprehensive document reviewing the key principles of each. [ABSTRACT FROM AUTHOR]

Fungal endophytes in cool-season grasses may affect communities at multiple trophic levels. However, it is unclear whether community-scale endophyte effects arise due to the endophyte itself or as a result of unique, endophyte-host interactions. We used a long-term field experiment to test whether common-toxic (CT) and non-ergot alkaloid-producing (novel) endophytes in Schedonorus arundinaceus (tall fescue) forage cultivars consistently affect communities across tall fescue hosts. Tilled plots (2 × 2 m; Guelph, ON) were seeded with Georgia 5 and Jesup cultivars containing either the CT or AR542 (novel) endophyte and allowed to be re-colonized by plant species from the local propagule pool. Non-seeded control plots were included to assess effects of seeding the non-native grass. We assessed plant, invertebrate, soil moisture, and soil nutrient responses to the endophyte-cultivar treatments after four growing seasons. Seeding tall fescue affected plant species abundances, but not richness, and did not consistently alter soil moisture and nutrient pools. Endophyte identity in the tall fescue cultivars affected the communities, but effects were not consistent between cultivars. Within Georgia 5, the AR542 endophyte reduced tall fescue abundance and altered the invertebrate community relative to CT plots. Within Jesup, the AR542 endophyte reduced species evenness and decreased soil moisture during dry periods relative to CT plots. Endophyte effects were not consistent between cultivars, and it is probable that the community-scale effects of endophyte infection in tall fescue cultivars arise due to unique interactions between cultivar and endophyte. [ABSTRACT FROM AUTHOR]

The endophyte Neotyphodium coenophialum in Schedonorus arundinaceus (tall fescue) may alter host interactions with specific resident species or shift the host's niche. These effects can be quantified by assessing tall fescue responses to, and effects on, the variation among resident species (selection) and resident species interactions (complementarity). To determine how N. coenophialum affects tall fescue, grassland microcosms containing 16 transplants of two, four, or eight resident species were seeded with endophyte-infected (E+) or endophyte-free (E−) Kentucky-31 (KY-31) tall fescue. All resident species were also grown in monoculture. Aboveground biomass was harvested 9 weeks after tall fescue was added (18 weeks' total growth). At harvest, more E+ than E− individuals were present and they represented a larger portion of the aboveground biomass across richness treatments, despite similar germination in concurrent trials. Tall fescue individuals were larger in microcosms dominated by more productive resident species (greater selection). In contrast, fewer E−, but not E+, individuals were present in microcosms with more facilitative interactions among the resident species (greater complementarity). E− and E+ tall fescue also affected resident species differently. High-richness E+ microcosms were more diverse and less dominated by productive species (lower selection) than E− microcosms. Thus, E+ KY-31 may more readily establish in, and affect, species-rich, functionally diverse communities as a result of niche shifts during establishment and negative effects on specific resident species. Although results need to be further tested under field conditions, it appears that endophyte presence may only facilitate KY-31 invasion into a limited suite of community types. [ABSTRACT FROM AUTHOR]

When a forensic DNA sample cannot be associated directly with a previously genotyped reference sample by standard short tandem repeat profiling, the investigation required for identifying perpetrators, victims, or missing persons can be both costly and time consuming. Here, we describe the outcome of a collaborative study using the Identitas Version 1 (v1) Forensic Chip, the first commercially available all-in-one tool dedicated to the concept of developing intelligence leads based on DNA. The chip allows parallel interrogation of 201,173 genome-wide autosomal, X-chromosomal, Y-chromosomal, and mitochondrial single nucleotide polymorphisms for inference of biogeographic ancestry, appearance, relatedness, and sex. The first assessment of the chip's performance was carried out on 3,196 blinded DNA samples of varying quantities and qualities, covering a wide range of biogeographic origin and eye/hair coloration as well as variation in relatedness and sex. Overall, 95 % of the samples ( N = 3,034) passed quality checks with an overall genotype call rate >90 % on variable numbers of available recorded trait information. Predictions of sex, direct match, and first to third degree relatedness were highly accurate. Chip-based predictions of biparental continental ancestry were on average ~94 % correct (further support provided by separately inferred patrilineal and matrilineal ancestry). Predictions of eye color were 85 % correct for brown and 70 % correct for blue eyes, and predictions of hair color were 72 % for brown, 63 % for blond, 58 % for black, and 48 % for red hair. From the 5 % of samples ( N = 162) with <90 % call rate, 56 % yielded correct continental ancestry predictions while 7 % yielded sufficient genotypes to allow hair and eye color prediction. Our results demonstrate that the Identitas v1 Forensic Chip holds great promise for a wide range of applications including criminal investigations, missing person investigations, and for national security purposes. [ABSTRACT FROM AUTHOR]

This paper proves that convex Brunnian links exist for every dimension n ≥ 3 by constructing explicit examples. These examples are three-component links which are higher-dimensional generalizations of the Borromean rings. [ABSTRACT FROM AUTHOR]

Deterministic lateral displacement arrays have shown great promise for size-based particle analysis and purification in medicine and biology. Here, we demonstrate that the use of an array of triangular rather than circular posts significantly enhances the performance of these devices by reducing clogging, lowering hydrostatic pressure requirements, and increasing the range of displacement characteristics. Experimental data and theoretical models are presented to create a compelling argument that future designs of deterministic lateral displacement arrays should employ triangular posts. The effect of practical considerations, such as vertex rounding, post size, and shape, is also discussed. [ABSTRACT FROM AUTHOR]

Bacterial communities provide important services. They break down pollutants, municipal waste and ingested food, and they are the primary means by which organic matter is recycled to plants and other autotrophs. However, the processes that determine the rate at which these services are supplied are only starting to be identified. Biodiversity influences the way in which ecosystems function, but the form of the relationship between bacterial biodiversity and functioning remains poorly understood. Here we describe a manipulative experiment that measured how biodiversity affects the functioning of communities containing up to 72 bacterial species constructed from a collection of naturally occurring culturable bacteria. The experimental design allowed us to manipulate large numbers of bacterial species selected at random from those that were culturable. We demonstrate that there is a decelerating relationship between community respiration and increasing bacterial diversity. We also show that both synergistic interactions among bacterial species and the composition of the bacterial community are important in determining the level of ecosystem functioning. [ABSTRACT FROM AUTHOR]

Presents statistical tests for departures from random expectation in spatial memory tasks. Common protocols for spatial memory experiments; Memory tasks with fixed number of samples; Memory tasks with fixed number of successes; Probability mass functions on site preferences; Parametric test applications; Distinguishing errors from sampling with replacement; Compound model construct.

Photosynthesis of Crassula helmsii, an amphibious aquatic macrophyte weed species, has been measured with respect to pH and irradiance. C. helmsii shows a marked diel fluctuation in titratable acidity, which can be accounted for by changing levels of malic acid. C. helmsii is unable to use HCOfor photosynthesis and exhibits generally low photosynthetic rates when CO is not limiting. The photon flux density at which the onset of light saturation of photosynthesis is reached (E) is low for aquatic macrophytes. Some advantages conferred on C. helmsii by the possession of crassulacean acid metabolism are an extension of the period of assimilation of dissolved inorganic carbon, resulting in a reduction in the limitation imposed on photosynthesis in aquatic environments by a very high CO diffusion resistance. [ABSTRACT FROM AUTHOR]

Cladophora glomerata (L.) Kz. was grown in Jaworski's algal culture medium and exposed to a fluctuating electromagnetic field which induced development of dark coloration, increased density and brittleness.After 4 weeks exposure, algae were unable to grow when transferred to unexposed culture medium. In addition, algal growth in culture medium exposed to a fluctuating magnetic field before the algae were introduced, was inhibited significantly compared with an appropriate control after 4 days, indicating a transfer of effect from the brief exposure to a magnetic field of less than 1 second to the 4-day period when growth was active. [ABSTRACT FROM AUTHOR]

Hydrocotyle ranunculoides L.f. is reported in this paper to be present at only 29 sites in the south east of England and in South Wales, in a wide range of water body types, which are typically slow-flowingand eutrophic. The current infestation is likely to have originated from various introductions from a single clone available at aquatic garden centres and nurseries in the U.K.. Experiments on the optimum chemical control method have shown that the plant is most susceptible to the herbicide 2,4-D amine applied at 4.23 kg ha-1 active ingredient (a.i.). Initial observations suggest that the species isresistant to the herbicide glyphosate applied at 2.16 kg a.i. ha-1. This resistance is postulated to be due to insufficient uptake of the herbicide through the leaf cuticle. [ABSTRACT FROM AUTHOR]