Metabolic Effects of the Incretin Mimetic Exenatide in the Treatment of Type 2 Diabetes

Interventional studies have demonstrated the impact of hyperglycemia on the development of vascular complications associated with type 2 diabetes, which underscores the importance of safely lowering glucose to as near-normal as possible. Among the current challenges to reducing the risk of vascular disease associated with diabetes is the management of body weight in a predominantly overweight patient population, and in which weight gain is likely with many current therapies. Exenatide is the first in a new class of agents termed incretin mimetics, which replicate several glucoregulatory effects of the endogenous incretin hormone, glucagon-like peptide-1 (GLP-1). Currently approved in the US as an injectable adjunct to metformin and/or sulfonylurea therapy, exenatide improves glycemic control through multiple mechanisms of action including: glucose-dependent enhancement of insulin secretion that potentially reduces the risk of hypoglycemia compared with insulin secretagogues; restoration of first-phase insulin secretion typically deficient in patients with type 2 diabetes; suppression of inappropriately elevated glucagon secretion to reduce postprandial hepatic output; and slowing the rate of gastric emptying to regulate glucose appearance into the circulation. Clinical trials in patients with type 2 diabetes treated with subcutaneous exenatide twice daily demonstrated sustained improvements in glycemic control, evidenced by reductions in postprandial and fasting glycemia and glycosylated hemoglobin (HbA1c) levels. Notably, improvements in glycemic control with exenatide were coupled with progressive reductions in body weight, which represents a distinct therapeutic benefit for patients with type 2 diabetes. Acute effects of exenatide on beta-cell responsiveness along with significant reductions in body weight in patients with type 2 diabetes may have a positive impact on disease progression and potentially decrease the risk of associated long-term complications

The value of performance weights and discussion in aggregated expert judgements

In risky situations characterized by imminent decisions, scarce resources, and insufficient data, policymakers rely on experts to estimate model parameters and their associated uncertainties. Different elicitation and aggregation methods can vary substantially in their efficacy and robustness. While it is generally agreed that biases in expert judgments can be mitigated using structured elicitations involving groups rather than individuals, there is still some disagreement about how to best elicit and aggregate judgments. This mostly concerns the merits of using performance‐based weighting schemes to combine judgments of different individuals (rather than assigning equal weights to individual experts), and the way that interaction between experts should be handled. This article aims to contribute to, and complement, the ongoing discussion on these topics

Collaborative conservation planning : Quantifying the contribution of expert engagement to identify spatial conservation priorities

The importance of expert input to spatial conservation prioritization outcomes is poorly understood. We quantified the impacts of refinements made during consultation with experts on spatial conservation prioritization of Christmas Island. There was just 0.57 correlation between the spatial conservation priorities before and after consultation, bottom ranked areas being most sensitive to changes. The inclusion of a landscape condition layer was the most significant individual influence. Changes (addition, removal, modification) to biodiversity layers resulted in a combined 0.2 reduction in correlation between initial and final solutions. Representation of rare species in top ranked areas was much greater after expert consultation; representation of widely distributed species changed relatively little. Our results show how different inputs have notably different impacts on the final plan. Understanding these differences helps plan time and resources for expert consultation.Peer reviewe

Clean and Green Urban Water Bodies Benefit Nocturnal Flying Insects and Their Predators, Insectivorous Bats

Nocturnal arthropods form the prey base for many predators and are an integral part of complex food webs. However, there is limited understanding of the mechanisms influencing invertebrates at urban water bodies and the potential flow-on effects to their predators. This study aims to: (i) understand the importance of standing water bodies for nocturnal flying insect orders, including the landscape- and local-scale factors driving these patterns; and (ii) quantify the relationship between insects and insectivorous bats. We investigated nocturnal flying insects and insectivorous bats simultaneously at water bodies (n = 58) and non-water body sites (n = 35) using light traps and acoustic recorders in Melbourne, Australia. At the landscape scale, we found that the presence of water and high levels of surrounding greenness were important predictors for some insect orders. At the water body scale, low levels of sediment pollutants, increased riparian tree cover and water body size supported higher insect order richness and a greater abundance of Coleopterans and Trichopterans, respectively. Most bat species had a positive response to a high abundance of Lepidopterans, confirming the importance of this order in the diet of insectivorous bats. Fostering communities of nocturnal insects in urban environments can provide opportunities for enhancing the prey base of urban nocturnal insectivores.DFG, 414044773, Open Access Publizieren 2019 - 2020 / Technische Universität Berli

Optical Absorption by Indirect Excitons in a Transition Metal Dichalcogenide Double Layer

We calculate the binding energy, transition energies, oscillator strength, and absorption coefficient of indirect excitons in transition metal dichalcogenide (TMDC) double layers separated by an integer number of hexagonal boron nitride (h-BN) monolayers. The absorption factor, a dimensionless quantity which gives the fraction of incoming photons absorbed by the indirect excitons in the double layer, is evaluated. The aforementioned optical quantities are obtained for transitions from the ground state to the first two excited states. All quantities are studied as a function of the interlayer separation, which may be experimentally controlled by varying the number of h-BN monolayers between the TMDC layers. Calculations are performed by using the exciton wave function and eigenenergies obtained for the Keldysh potential. For each material, we choose a combination of the exciton reduced mass and the dielectric screening length from the existing literature which give the largest and the smallest indirect exciton binding energy. These combinations of material parameters provide upper and lower bounds on all quantities presented. Our findings can be examined experimentally via two-photon spectroscopy.Comment: 13 pages, 3 figure