Modelling understorey dynamics in temperate forests under global change : challenges and perspectives

The understorey harbours a substantial part of vascular plant diversity in temperate forests and plays an important functional role, affecting ecosystem processes such as nutrient cycling and overstorey regeneration. Global change, however, is putting these understorey communities on trajectories of change, potentially altering and reducing their functioning in the future. Developing mitigation strategies to safeguard the diversity and functioning of temperate forests in the future is challenging and requires improved predictive capacity. Process-based models that predict understorey community composition over time, based on first principles of ecology, have the potential to guide mitigation endeavours but such approaches are rare. Here, we review fourteen understorey modelling approaches that have been proposed during the last three decades. We evaluate their inclusion of mechanisms that are required to predict the impact of global change on understorey communities. We conclude that none of the currently existing models fully accounts for all processes that we deem important based on empirical and experimental evidence. Based on this review, we contend new models are needed to project the complex impacts of global change on forest understoreys. Plant functional traits should be central to such future model developments, as they drive community assembly processes and provide valuable information on the functioning of the understorey. Given the important role of the overstorey, a coupling of understorey models to overstorey models will be essential to predict the impact of global change on understorey composition and structure, and how it will affect the functioning of temperate forests in the future

Revealing criterial vagueness in inconsistencies

Sixty undergraduate students made category membership decisions for each of 132 candidate exemplar-category name pairs (e.g., chess – Sports) in each of two separate sessions. They were frequently inconsistent from one session to the next, both for nominal categories such as Sports and Fish, and ad hoc categories such as Things You Rescue from a Burning House. A mixture model analysis revealed that several of these inconsistencies could be attributed to criterial vagueness: participants adopting different criteria for membership in the two sessions. This finding indicates that categorization is a probabilistic process, whereby the conditions for applying a category label are not invariant. Individuals have various functional meanings of nominal categories at their disposal and entertain competing goals for ad hoc categories

III-V-on-silicon anti-colliding pulse-type mode-locked laser

An anti-colliding pulse-type III–V-on-silicon passively mode-locked laser is presented for the first time based on a III–V-on-silicon distributed Bragg reflector as outcoupling mirror implemented partially underneath the III–V saturable absorber. Passive mode-locking at 4.83 GHz repetition rate generating 3 ps pulses is demonstrated. The generated fundamental RF tone shows a 1.7 kHz 3 dB linewidth. Over 9 mW waveguide coupled output power is demonstrated

Ischemic gallbladder perforation

Background: A 63-year-old woman was admitted to the department of vascular surgery with abdominal angor and hypertension. Abdominal CT angiography revealed occlusion of the celic trunk and superior mesenteric trunk and severe stenosis on the left renal artery. Stenting of the left renal artery was successfully performed. One week after the procedure, the patient was admitted at the emergency department with severe abdominal pain, which began a few hours before admission

Spectroscopic and quartz crystal microbalance (QCM) characterisation of protein-based MIPs

We have studied acrylamide-based polymers of varying hydrophobicity (acrylamide, AA; N-hydroxymethylacrylamide, NHMA; N-isopropylacrylamide, NiPAm) for their capability of imprinting protein. Rebinding capacities (Q) from spectroscopic studies were highest for bovine haemoglobin (BHb) MIPs based on AA, Q = 4.8 ± 0.21 76 ± 0.5%). When applied to the QCM sensor as thin-film MIPs, NHMA MIPs were found to exhibit best discrimination between MIP and non-imprinted control polymer (NIP) in the order of NiPAm < AA < NHMA. The extent of template removal and rebinding, using both crystal impedance and frequency measurements, demonstrated that 10% (w/v):10% (v/v) sodium dodecyl sulphate:acetic acid (pH 2.8) was efficient at eluting template BHb (with 80 ± 10% removal). Selectivity studies of NHMA BHb-MIPs revealed higher adsorption and selective recognition properties to BHb (64.5 kDa) when compared to non-cognate BSA (66 kDa), myoglobin (Mb, 17.5 kDa), lysozyme (Lyz, 14.7 kDa) thaumatin (Thau, 22 kDa) and trypsin (Tryp, 22.3 kDa). The QCM gave frequency shifts of ∼1500 ± 50 Hz for template BHb rebinding in both AA and NHMA MIPs, whereas AA-based MIPs exhibited an interference signal of ∼2200 ± 50 Hz for non-cognate BSA in comparison to a ∼500 ± 50 Hz shift with NHMA MIPs. Our results show that NHMA-based hydrogel MIP are superior to AA and NIPAM