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Transpiration efficiency: new insights into an old story

Producing more food per unit of water has never been as important as it is at present, and the demand for water by economic sectors other than agriculture will necessarily put a great deal of pressure on a dwindling resource, leading to a call for increases in the productivity of water in agriculture. This topic has been given high priority in the research agenda for the last 30 years, but with th

Plant biosecurity policy-making modelled on the human immune system: What would it look like?

This paper takes inspiration from the field of bio-mimicry to suggest what a plant biosecurity system might look like if it was modelled on the human immune system. We suggest structural and institutional changes to current biosecurity systems that would facilitate adaptive preparation and response policies, focusing particularly on the Australian plant biosecurity system. By improving information

Antonym canonicity: Temporal and contextual manipulations

Abstract in UndeterminedPrevious research on antonyms has shown that some pairings form more felicitous couplings than others. Following up on that research, we conducted two semantic categorization experiments using Event Related Potentials to establish whether there are neurophysiological differences related to levels of antonym canonicity. In Experiment 1, the members of canonical antonym pairs

The AVI-R2: An inventory for a differentiated diagnosis of alcohol problems

Often in clinical practice, a diagnosis of alcohol dependence or abuse does not provide enough information to establish an adequate treatment plan. Hence, multidimensional instruments have been constructed better to describe the extent and character of a patient's alcohol problem. The purpose of the current article is to present the AVI-R2, a self-report test that provides a standardized and diffe

Combined design of VSC-HVDC and PSS controllers for LFO damping enhancement

The purpose of this paper is to present a novel combined design of the voltage source converter–high voltage direct current (VSC-HVDC) and the power system stabilizer (PSS) controllers to obtain a better dynamical response. The proposed technique is applied to enhance the damping of the power system low-frequency oscillations (LFOs) and results are compared with traditional design. A fuzzy logic c

A new predictive tool for saturated critical heat flux in micro/mini-channels: Effect of the heated length-to-diameter ratio

This paper verified the macro-to-mini-scale criterion BoRe10.5=200 because data points where BoRe10.5≤200 and BoRe10.5>200 show very different trends for the entire database (1672 data points). Boiling number at critical heat flux (Blchf) decreases greatly with heated length-to-diameter ratio (Lh/dhe) when Lh/dhe is small while a relatively smooth trend occurs with large Lh/dhe values. The paper p

Fewer invited talks by women in evolutionary biology symposia

Lower visibility of female scientists, compared to male scientists, is a potential reason for the under-representation of women among senior academic ranks. Visibility in the scientific community stems partly from presenting research as an invited speaker at organized meetings. We analysed the sex ratio of presenters at the European Society for Evolutionary Biology (ESEB) Congress 2011, where all

External Electric Field-Dependent Photoinduced Charge Transfer in a Donor-Acceptor System for an Organic Solar Cell

External electric field is incorporated into the generalized Mulliken-Hush model and Marcus theory. With this new development, we have investigated the field-dependent electronic structure and rate of photoinduced charge transfer in organic donor-acceptor dyad using time-dependent density functional theory and extensive multidimensional visualization techniques. The model is used to evaluate the i

Immune Indexes of Larks from Desert and Temperate Regions Show Weak Associations with Life History but Stronger Links to Environmental Variation in Microbial Abundance

Immune defense may vary as a result of trade-offs with other life-history traits or in parallel with variation in antigen levels in the environment. We studied lark species (Alaudidae) in the Arabian Desert and temperate Netherlands to test opposing predictions from these two hypotheses. Based on their slower pace of life, the trade-off hypothesis predicts relatively stronger immune defenses in de

To measure the impact of hearing protectors on the perception of speech in noise

Objective: To propose and evaluate a new method for assessing the potential impact on speech intelligibility when wearing a hearing protection device (HPD) in a noisy environment. Design: The method is based on a self adaptive method for finding the speech reception threshold (SRT) using speech material from the Callsign acquisition test (CAT) presented at a constant level while adjusting the leve

The executioners sing a new song: killer caspases activate microglia

Activation of microglia and inflammation-mediated neurotoxicity are suggested to have key roles in the pathogenesis of several neurodegenerative disorders. We recently published an article in Nature revealing an unexpected role for executioner caspases in the microglia activation process. We showed that caspases 8 and 3/7, commonly known to have executioner roles for apoptosis, can promote microgl

Quantum dot photodegradation due to CdSe-ZnO charge transfer: Transient absorption study

We study changes in ultrafast transient absorption due to photodegradation of quantum dots attached to ZnO nanowire. The time-resolved measurements reveal impact of photodegradation on three distinct kinetic components present in transient absorption tau similar to 7 ps, 80 ps, and 7.5 ns). In addition, we observe superlinear dependence of photodegradation rate on concentration of excited electron

Evidence for ligand hydrolysis and Fe(III) reduction in the dissolution of goethite by desferrioxamine-B

Desferrioxamine-B (DFOB) is a bacterial trihydroxamate siderophore and probably the most studied to date. However, the manner in which DFOB adsorbs at mineral surfaces and promotes dissolution is still under discussion. Here we investigated the adsorption and dissolution reactions in the goethite-DFOB system using both in situ infrared spectroscopic and quantitative analytical methods. Experiments

Elevated plasma levels of heparin-binding protein in intensive care unit patients with severe sepsis and septic shock

Introduction: Rapid detection of, and optimized treatment for, severe sepsis and septic shock is crucial for successful outcome. Heparin-binding protein (HBP), a potent inducer of increased vascular permeability, is a potentially useful biomarker for predicting outcome in patients with severe infections. Our aim was to study the systemic release and dynamics of HBP in the plasma of patients with s

Heat-induced aggregation of thylakoid membranes affect their interfacial properties.

Many of our most popular lipid containing foods are in emulsion form. These foods are often highly palatable with high caloric density, that subsequently increases the risk of overconsumption and possibly lead to obesity. Regulating the lipid bioavailability of high-fat foods is one approach to prevent overconsumption. Thylakoids, the chloroplast membrane, creates a barrier around lipid droplets,

Batch-Specific Discrimination Using Nuclear Quadrupole Resonance Spectroscopy

In this paper, we report on the identification of batches of analgesic paracetamol (acetaminophen) tablets using nitrogen-14 nuclear quadrupole resonance spectroscopy (N-14 NQR). The high sensitivity of NQR to the electron charge distribution surrounding the quadrupolar nucleus enables the unique characterization of the crystal structure of the material. Two hypothesis were tested on batches of th

Determination of Nicotine Absorption from Multiple Tobacco Products and Nicotine Gum

Snus is a smokeless tobacco product traditionally used in Scandinavia and available in pouched or loose forms. The objective of this study was to determine nicotine absorption for current pouched and loose snus products in comparison with a cigarette and an over-the-counter nicotine gum. We conducted an open-label, randomized, 6-way, crossover study involving 20 healthy snus and cigarette users. O

A Combinatorial Approach to $L_1$-Matrix Factorization

Recent work on low-rank matrix factorization has focused on the missing data problem and robustness to outliers and therefore the problem has often been studied under the $L_1$-norm. However, due to the non-convexity of the problem, most algorithms are sensitive to initialization and tend to get stuck in a local optimum. In this paper, we present a new theoretical framework aimed at achieving opt