State-space models' dirty little secrets: even simple linear Gaussian models can have estimation problems

State-space models (SSMs) are increasingly used in ecology to model time-series such as animal movement paths and population dynamics. This type of hierarchical model is often structured to account for two levels of variability: biological stochasticity and measurement error. SSMs are flexible. They can model linear and nonlinear processes using a variety of statistical distributions. Recent ecological SSMs are often complex, with a large number of parameters to estimate. Through a simulation study, we show that even simple linear Gaussian SSMs can suffer from parameter- and state-estimation problems. We demonstrate that these problems occur primarily when measurement error is larger than biological stochasticity, the condition that often drives ecologists to use SSMs. Using an animal movement example, we show how these estimation problems can affect ecological inference. Biased parameter estimates of a SSM describing the movement of polar bears (\textit{Ursus maritimus}) result in overestimating their energy expenditure. We suggest potential solutions, but show that it often remains difficult to estimate parameters. While SSMs are powerful tools, they can give misleading results and we urge ecologists to assess whether the parameters can be estimated accurately before drawing ecological conclusions from their results

Uncertainties of the Inclusive Higgs Production Cross Section at the Tevatron and the LHC

We study uncertainties of the predicted inclusive Higgs production cross section due to the uncertainties of parton distribution functions (PDF). Particular attention is given to bbH Yukawa coupling enhanced production mechanisms in beyond SM scenarios, such as MSSM. The PDF uncertainties are determined by the robust Lagrange Multiplier method within the CTEQ global analysis framework. We show that PDF uncertainties dominate over theoretical uncertainties of the perturbative calculation (usually estimated by the scale dependence of the calculated cross sections), except for low Higgs masses at LHC. Thus for the proper interpretation of any Higgs signal, and for better understanding of the underlying electroweak symmetry breaking mechanism, it is important to gain better control of the uncertainties of the PDFs.Comment: LaTeX, JHEP, 19 pages, 14 figure

Can on-site management mitigate nitrogen deposition impacts in non-wooded habitats?

Nitrogen (N) deposition is a major cause of plant biodiversity loss, with serious implications for appropriate management of protected sites. Reducing N emissions is the only long-term solution. However, on-site management has the potential to mitigate some of the adverse effects of N deposition. In this paper we review how management activities such as grazing, cutting, burning, hydrological management and soil disturbance measures can mitigate the negative impacts of N across a range of temperate habitats (acid, calcareous and neutral grasslands, sand dunes and other coastal habitats, heathlands, bogs and fens). The review focuses mainly on European habitats, which have a long history of N deposition, and it excludes forested systems. For each management type we distinguish between actions that improve habitat suitability for plant species of conservation importance, and actions that immobilize N or remove it from the system. For grasslands and heathlands we collate data on the quantity of N removal by each management type. Our findings show that while most activities improve habitat suitability, the majority do little to slow or to reduce the amount of N accumulating in soil pools at current deposition rates. Only heavy cutting/mowing with removal in grasslands, high intensity burns in heathlands and sod cutting remove more N than comes in from deposition under typical management cycles. We conclude by discussing some of the unintended consequences of managing specifically for N impacts, which can include damage to non-target species, alteration of soil processes, loss of the seedbank and loss of soil carbon

Quantum discrete Dubrovin equations

The discrete equations of motion for the quantum mappings of KdV type are given in terms of the Sklyanin variables (which are also known as quantum separated variables). Both temporal (discrete-time) evolutions and spatial (along the lattice at a constant time-level) evolutions are considered. In the classical limit, the temporal equations reduce to the (classical) discrete Dubrovin equations as given in a previous publication. The reconstruction of the original dynamical variables in terms of the Sklyanin variables is also achieved.Comment: 25 page

Engineering restoration and gaseous carbon uptake on a degraded bog: the role of Eriophorum angustifolium and micropropagated Sphagnum

Degraded peatlands are significant sources of carbon greenhouse gases (CGHG), and their recovery can make significant contributions to climate change mitigation as well as deliver biodiversity benefits. Sphagnum mosses are key species for northern peatland formation and re-introduction is often needed for successful ecohydrological restoration of degraded bogs, but natural sources are scarce and often protected. Micropropagated Sphagnum moss products (BeadaMoss®) were developed to alleviate this constraint. This research explored in detail, for the first time, the CGHG fluxes on a cut-over lowland peatland restoration site where micropropagated Sphagnum was introduced to an existing ‘nurse crop’ of Eriophorum angustifolium, and tested the influence of vegetation maturity. Ecosystem CGHG flux was measured using closed chambers at plot scale in areas of both mature and immature E. angustifolium with and without application of BeadaGel™ Sphagnum, with control plots on bare peat. Studies were conducted over two years of contrasting weather patterns. In Year 1, mean net (CO2e) CGHG uptake on vegetated plots was -2.33 (minimum 1.55, maximum -5.55) t ha-1 yr-1 with increasing CGHG uptake as vegetation matured. In Year 2, gross photosynthesis reduced significantly during the 2018 summer drought resulting in a small mean net CGHG emission of 0.11 (minimum 2.21 maximum -1.22) t ha-1 yr-1 . Sphagnum application within immature vegetation resulted in greater CGHG uptake in both years, but was not as beneficial within mature vegetation. CGHG emission from bare peat (3.79 t ha-1 yr-1 overall) showed the magnitude of avoided losses. Methane flux contributed significantly to CGHG emission but was not closely related to water table depth. Application of Sphagnum within E. angustifolium can deliver good CGHG flux results in the early stages of degraded lowland bog recovery but cannot fully mitigate vulnerability to climate change scenarios

How far back do we need to look to capture diagnoses in electronic health records? A retrospective observational study of hospital electronic health record data

Objectives: Analysis of routinely collected electronic health data is a key tool for long-term condition research and practice for hospitalised patients. This requires accurate and complete ascertainment of a broad range of diagnoses, something not always recorded on an admission document at a single point in time. This study aimed to ascertain how far back in time electronic hospital records need to be interrogated to capture long-term condition diagnoses. Design: Retrospective observational study of routinely collected hospital electronic health record data. Setting: Queen Elizabeth Hospital Birmingham (UK)-linked data held by the PIONEER acute care data hub. Participants: Patients whose first recorded admission for chronic obstructive pulmonary disease (COPD) exacerbation (n=560) or acute stroke (n=2142) was between January and December 2018 and who had a minimum of 10 years of data prior to the index date. Outcome measures: We identified the most common International Classification of Diseases version 10-coded diagnoses received by patients with COPD and acute stroke separately. For each diagnosis, we derived the number of patients with the diagnosis recorded at least once over the full 10-year lookback period, and then compared this with shorter lookback periods from 1 year to 9 years prior to the index admission. Results: Seven of the top 10 most common diagnoses in the COPD dataset reached >90% completeness by 6 years of lookback. Atrial fibrillation and diabetes were >90% coded with 2–3 years of lookback, but hypertension and asthma completeness continued to rise all the way out to 10 years of lookback. For stroke, 4 of the top 10 reached 90% completeness by 5 years of lookback; angina pectoris was >90% coded at 7 years and previous transient ischaemic attack completeness continued to rise out to 10 years of lookback. Conclusion: A 7-year lookback captures most, but not all, common diagnoses. Lookback duration should be tailored to the conditions being studied

Do UK universities communicate their brands effectively through their websites?

This paper attempts to explore the effectiveness of UK universities’ websites. The area of branding in higher education has received increasing academic investigation, but little work has researched how universities demonstrate their brand promises through their websites. The quest to differentiate through branding can be challenging in the university context, however. It is argued that those institutions that have a strong distinctive image will be in a better position to face a changing future. Employing a multistage methodology, the web pages of twenty UK universities were investigated by using a combination of content and multivariable analysis. Results indicated ‘traditional values’ such as teaching and research were often well communicated in terms of online brand but ‘emotional values’ like social responsibility and the universities’ environments were less consistently communicated, despite their increased topicality. It is therefore suggested that emotional values may offer a basis for possible future online differentiation

Changes in nitrogen functional genes and microbial populations in soil profiles of a peatland under different burning regimes

Microbes in peatlands provide key ecosystem services and are essential for their role in biogeochemical cycling. Prescribed burning is a common aspect of peatland management but the practice has been criticized for being ecologically damaging due to its effect on the biological, chemical and physical properties of the soil. It is poorly understood how burning affects soil N cycling and previous studies have focused predominantly on the topsoil whilst giving less attention to changes with soil depth. This study investigated the changes of microbial abundance (bacterial 16S rRNA and fungal 18S rRNA) and the abundance of N-cycle functional genes involved in archaeal and bacterial ammonia oxidation (amoA-AOA and amoA-AOB), denitrification (nirK and nirS), N fixation (nifH) and organic N decomposition (chiA) in soil profiles across three burn treatments on a managed peatland landscape (a ‘non-burn’ since 1954 control, 20 years burn interval, and 10 years burn interval). Our results indicate the abundance of bacterial 16S rRNA and fungal 18 s rRNA was affected by burn treatment, soil depth and their interaction and were greater in the non-burn control plots. The abundances of amoA-AOA, amoA-AOB, and nifH were significantly higher in the topsoil of the non-burn control plots while the abundance of nirK was higher in plots subject to short rotation and long rotation burn regimes but also decreased significantly with soil depth. The abundance of nirS was not affected by burn treatment or soil depth. ChiA abundance was affected by burn treatment, soil depth and their interaction. N-cycle functional gene abundance responded differently to environmental factors associated with prescribed burning and varied with soil depth. These findings suggest that the practice of burning affects microbial N turnover potential and provides an important insight into the soil N-cycling potential of peatlands under different burning regimes

Using the theory of planned behavior to explore environmental behavioral intentions in the workplace

This paper presents a study using the theory of planned behavior (TPB) to explore environmental behavioral intentions in a workplace setting. The first stage of the research process was the development of a questionnaire covering TPB constructs, their antecedent beliefs, and environmental behavioral intentions across three scenarios (switching off PCs every time employees left their desks for an hour or more; using video-conferencing for meetings that would otherwise require travel; and recycling as much waste as possible), using best practice guidelines to ensure that it was specific and precisely defined for the target population. This was then administered to N = 449 participants, with the resulting dataset used to test hypotheses relating antecedent beliefs to behavioral intentions via the potentially mediating effect of TPB constructs. TPB constructs were found to explain between 46% and 61% of the variance in employee intentions to engage in three environmental behaviors, and to mediate the effects of specific antecedent beliefs upon employee intentions to engage in these behaviors. The results form a basis upon which interventions could be developed within the host organization, and are discussed in relation to their implications, in terms of theory, practice and future research