Valuing the biodiversity gains from protecting native plant communities from bitou bush (Chrysanthemoides monilifera subsp rotundata (DC.) T.Norl.) in New South Wales: application of the defensive expenditure method

Valuation of the gains from protection of biodiversity is difficult because the services that provide the benefits do not normally pass through markets where prices can form. But the services sometimes pass through markets where consumers or producers behave in a market-oriented manner, and so the values implicit in this behaviour can be identified and derived. Estimates of the benefits of biodiversity protection are derived from the costs of protecting native plant communities from a major weed in Australia, by following this approach. In 1999, invasion of coastal areas of New South Wales by bitou bush (Chrysanthemoides monilifera subsp. rotundata (DC.) T. Norl.) was listed as a key process threatening native plants under the NSW Threatened Species Conservation Act 1995. In accordance with the Act, the Department of Environment and Climate Change prepared a Threat Abatement Plan (TAP) to reduce the impacts of bitou bush on biodiversity at each threatened site. The costs of protecting sites vary closely with the number of priority native species and communities at each site. Following standard economic assumptions about market transactions, these costs are interpreted to provide values the benefits of protecting extra species, communities, and sites. Key words: Bitou bush, Chrysanthemoides monilifera, threat abatement plan, valuation of biodiversity, benefit-cost analysis, weed control, defensive-expenditure method.Bitou bush, Chrysanthemoides monilifera, threat abatement plan, valuation of biodiversity, benefit-cost analysis, weed control, defensive-expenditure method, Demand and Price Analysis, Environmental Economics and Policy,

Semi- and fully synthetic carbohydrate vaccines against pathogenic bacteria : recent developments

The importance of vaccine-induced protection was repeatedly demonstrated over the last three decades and emphasized during the recent COVID-19 pandemic as the safest and most effective way of preventing infectious diseases. Vaccines have controlled, and in some cases, eradicated global viral and bacterial infections with high efficiency and at a relatively low cost. Carbohydrates form the capsular sugar coat that surrounds the outer surface of human pathogenic bacteria. Specific surface-exposed bacterial carbohydrates serve as potent vaccine targets that broadened our toolbox against bacterial infections. Since first approved for commercial use, antibacterial carbohydrate-based vaccines mostly rely on inherently complex and heterogenous naturally derived polysaccharides, challenging to obtain in a pure, safe, and cost-effective manner. The introduction of synthetic fragments identical with bacterial capsular polysaccharides provided well-defined and homogenous structures that resolved many challenges of purified polysaccharides. The success of semisynthetic glycoconjugate vaccines against bacterial infections, now in different phases of clinical trials, opened up new possibilities and encouraged further development towards fully synthetic antibacterial vaccine solutions. In this mini-review, we describe the recent achievements in semi- and fully synthetic carbohydrate vaccines against a range of human pathogenic bacteria, focusing on preclinical and clinical studies

The Complexity of Routing with Few Collisions

We study the computational complexity of routing multiple objects through a network in such a way that only few collisions occur: Given a graph $G$ with two distinct terminal vertices and two positive integers $p$ and $k$, the question is whether one can connect the terminals by at least $p$ routes (e.g. paths) such that at most $k$ edges are time-wise shared among them. We study three types of routes: traverse each vertex at most once (paths), each edge at most once (trails), or no such restrictions (walks). We prove that for paths and trails the problem is NP-complete on undirected and directed graphs even if $k$ is constant or the maximum vertex degree in the input graph is constant. For walks, however, it is solvable in polynomial time on undirected graphs for arbitrary $k$ and on directed graphs if $k$ is constant. We additionally study for all route types a variant of the problem where the maximum length of a route is restricted by some given upper bound. We prove that this length-restricted variant has the same complexity classification with respect to paths and trails, but for walks it becomes NP-complete on undirected graphs

Filling-induced Mott transition and pseudogap physics in the triangular lattice Hubbard model

It has been reported that upon doping a Mott insulator, there can be a crossover to a strongly correlated metallic phase followed by a first-order transition to another thermodynamically stable metallic phase. We call this first-order metal-metal transition the Sordi transition. To show theoretically that this transition is observable, it is important to provide calculations in situations where magnetic phase transitions do not hide the Sordi transition. It is also important to show that it can be found on large clusters and with different approaches. Here, we use the dynamical cluster approximation to reveal the Sordi transition on a triangular lattice at finite temperature in situations where there is no long-range magnetic correlations. This is relevant for experiments on candidate spin-liquid organics. We also show that the metallic phase closest to the insulator is a distinct pseudogap phase that occurs because of strong interactions and short-range correlations

Phase Transition and Strong Predictability

The statistical mechanical interpretation of algorithmic information theory (AIT, for short) was introduced and developed in our former work [K. Tadaki, Local Proceedings of CiE 2008, pp.425-434, 2008], where we introduced the notion of thermodynamic quantities into AIT. These quantities are real functions of temperature T>0. The values of all the thermodynamic quantities diverge when T exceeds 1. This phenomenon corresponds to phase transition in statistical mechanics. In this paper we introduce the notion of strong predictability for an infinite binary sequence and then apply it to the partition function Z(T), which is one of the thermodynamic quantities in AIT. We then reveal a new computational aspect of the phase transition in AIT by showing the critical difference of the behavior of Z(T) between T=1 and T<1 in terms of the strong predictability for the base-two expansion of Z(T).Comment: 5 pages, LaTeX2e, no figure

A note on the differences of computably enumerable reals

We show that given any non-computable left-c.e. real α there exists a left-c.e. real β such that α≠β+γ for all left-c.e. reals and all right-c.e. reals γ. The proof is non-uniform, the dichotomy being whether the given real α is Martin-Loef random or not. It follows that given any universal machine U, there is another universal machine V such that the halting probability of U is not a translation of the halting probability of V by a left-c.e. real. We do not know if there is a uniform proof of this fact

Mott transition, Widom line and pseudogap in the half-filled triangular lattice Hubbard model

The Mott transition is observed experimentally in materials that are magnetically frustrated so that long-range order does not hide the Mott transition at finite temperature. The Hubbard model on the triangular lattice at half-filling is a paradigmatic model to study the interplay of interactions and frustration on the normal-state phase diagram. We use the dynamical cluster approximation with continuous time auxiliary field quantum Monte Carlo to solve this model for 1, 4, 6, 12, and 16 site clusters with detailed analysis performed for the 6 site cluster. We show that a) for every cluster there is an inflection point in the double occupancy as a function of interaction, defining a Widom line that extends above the critical point of the first-order Mott transition; b) the presence of this line and the cluster size dependence argue for the observability of the Mott transition at finite temperature in the thermodynamic limit; c) the loss of spectral weight in the metal to Mott insulator transition as a function of temperature and for strong interactions is momentum dependent, the hallmark of a pseudogap. That pseudogap spans a large region of the phase diagram near the Mott transition.Comment: Open source version of the published paper. 16 pages, 8 figures, LaTe

Exoplanet science with the LBTI: instrument status and plans

The Large Binocular Telescope Interferometer (LBTI) is a strategic instrument of the LBT designed for high-sensitivity, high-contrast, and high-resolution infrared (1.5-13 $\mu$m) imaging of nearby planetary systems. To carry out a wide range of high-spatial resolution observations, it can combine the two AO-corrected 8.4-m apertures of the LBT in various ways including direct (non-interferometric) imaging, coronagraphy (APP and AGPM), Fizeau imaging, non-redundant aperture masking, and nulling interferometry. It also has broadband, narrowband, and spectrally dispersed capabilities. In this paper, we review the performance of these modes in terms of exoplanet science capabilities and describe recent instrumental milestones such as first-light Fizeau images (with the angular resolution of an equivalent 22.8-m telescope) and deep interferometric nulling observations.Comment: 12 pages, 6 figures, Proc. SPI

The generalized Robinson-Foulds metric

The Robinson-Foulds (RF) metric is arguably the most widely used measure of phylogenetic tree similarity, despite its well-known shortcomings: For example, moving a single taxon in a tree can result in a tree that has maximum distance to the original one; but the two trees are identical if we remove the single taxon. To this end, we propose a natural extension of the RF metric that does not simply count identical clades but instead, also takes similar clades into consideration. In contrast to previous approaches, our model requires the matching between clades to respect the structure of the two trees, a property that the classical RF metric exhibits, too. We show that computing this generalized RF metric is, unfortunately, NP-hard. We then present a simple Integer Linear Program for its computation, and evaluate it by an all-against-all comparison of 100 trees from a benchmark data set. We find that matchings that respect the tree structure differ significantly from those that do not, underlining the importance of this natural condition.Comment: Peer-reviewed and presented as part of the 13th Workshop on Algorithms in Bioinformatics (WABI2013