Potential Mismatch Research Articles

Perceived accessibility: What it is and why it differs from calculated accessibility measures based on spatial data

Accessibility is usually evaluated using indicators calculated from spatial data. However, perceived accessibility, defined as the perceived potential to participate in spatially dispersed opportunities, is often poorly reflected by these calculated measures. This paper sets out to explain the mechanisms that lead to these mismatches. A conceptual model is constructed to establish what factors shape perceived accessibility. A schematic framework shows that mismatches between a calculated indicator and perceptions can stem from inaccuracies in awareness as well as from inaccuracies in the measure if the measure fails to take account of the subjective evaluations of accessibility components. When evaluating the performance of land-use and transport system configurations, calculated measures based on spatial and transport data only serve as proxies for how accessibility is actually experienced. This paper argues that bringing perceived accessibility to the fore of accessibility-based planning, by acknowledging and evaluating potential mismatches with calculated accessibility indicators, will advance the evolution from mobility-based to accessibility-based planning.

An Algorithm for the Broad Evaluation of Potential Matches between Actuator Concepts and Heavy-Duty Mobile Applications

In recent years, a variety of novel actuator concepts for the implements of heavy-duty mobile machines (HDMMs) has been proposed by industry and academia. Mostly, novel concepts aim at improving the typically low energy efficiency of state-of-the-art hydraulic valve-controlled actuators. However, besides energy-efficiency, many aspects that are crucial for a successful concept integration are often neglected in studies. Furthermore, most of the time, a specific HDMM is focused as an application while other HDMM types can show very different properties that might make a novel concept less suitable. In order to take more aspects and HDMM types into account when evaluating actuator concepts, this paper proposes a novel evaluation algorithm, which calculates so-called mismatch values for each potential actuator-application match, based on different problem aspects that can indicate a potential mismatch between a certain actuator concept and an HDMM. The lower the mismatch value, which depends on actuator characteristics as well as HDMM attributes, the more potential is the match. At the same time, the modular nature of the algorithm allows to evaluate a large number of possible matches at once, with low effort. For the performance demonstration of the algorithm, 36 potential matches formed out of six actuator concepts and six HDMM types are exemplarily evaluated. The resulting actuator concept ratings for the six different HDMMs are in line with general reasoning and confirm that the evaluation algorithm is a powerful tool to get a first, quick overview of a large solution space of actuator-HDMM matches. However, analyzing the limitations of the algorithm also shows that it cannot replace conventional requirements engineering and simulation studies if detailed and reliable results are required.

The multiple stakeholder approach to real-world evidence (RWE) generation: observing multidisciplinary expert consensus on quality indicators of rare disease patient registries (RDRs)

Introduction Those invested in the outcome of specific decisions may seek to inform the decision-maker by generating relevant evidence. With multiple decision-makers, the evidence generator benefits from understanding whether their needs differ. This was explored using relevant stakeholders’ preferences on quality indicators (QIs) of rare disease patient registries (RDRs), a common vehicle for generating evidence, to support the adoption of new medicines. Methods The Jandhyala method was used to compare the observed consensus on RDR quality indicators from each stakeholder group (SHG) and between the combined pharmaceutical (pharma) and non-pharmaceutical (non-pharma) SHG population. Results All non-pharmaceutical stakeholder groups were equally unique – suggesting QIs peculiar to themselves – Patients (13/102; 12.75%); Payors (5/102; 4.90%); Prescribers (7/102; 6.86%) to the same degree. Non-pharmaceutical stakeholders generated 31/102 (30.39%) unique QIs. Pharma stakeholder generated 25/102 (24.51%). This totals 56/102 (54.90%) QIs without a match. Two QIs were unanimously suggested and agreed upon by all SHGs (7/7; 100%) – “Engages with patients and gains their buy-in” and “Includes a core data set as part of outcomes”. There was homogenous consensus on common QIs between: Commercial – Market Access (13/52; 25%; p = .005) SHGs; Commercial – Medical Affairs (9/47; 19.15%; p = .001) SHGs; Commercial – Payor (11/41; 21.15%; p = .012) SHGs, and Market Access – Regulatory Affairs (10/41; 19.61%; p = .008) SHGs. Conclusions A multiple stakeholder approach for generating real-world evidence can be justified. The potential mismatch of 54.9% between pharma and non-pharma stakeholders indicates a critical misalignment between generator and consumer of its RWE. Pharmaceutical SHG’s were highlighted for greater alignment with Patients and Payor (non-pharma) groups.

Selective contacts and fill factor limitations in heterojunction solar cells

AbstractCrystalline silicon‐based heterojunction (HJ) solar cells are becoming the best choice for manufacturing companies, because of the low temperature processes useful for very thin silicon wafers and the possibility to easily achieve cells efficiencies higher than 22% on n‐type silicon wafers. However, the maximum cell efficiency is still limited by the typical Fill Factor (FF) value of 82%. This issue is due to several factors, some of which are sometimes underestimated, like the base contact. Indeed, a potential mismatch between the work functions of the transparent conductive oxide and the base doped layer can give rise to a small barrier against electrons collection, which is not easy to recognize when the cell FF overcomes 80%. Also a low doping efficiency of the p‐type amorphous layer at the emitter side can negatively affect the FF. In this case, even if high efficiency cells are produced, their full potential is still unexploited. Thus, both selective contacts of the cell, even if apparently optimized to achieve very good results, can hide problems that limit the final cell FF and efficiency. In a previous work, an experimental method and a model to individuate hidden barriers at the base contact on n‐type crystalline silicon‐based HJs have been provided. In this paper, that model is applied to experimental data obtained from the characterization of both commercial and laboratory level HJ solar cells. Moreover, an easy method to recognize the presence of a barrier to the charge transport at the emitter side of the cell is illustrated.

Calculation of ocular magnification in phakic and pseudophakic eyes based on anterior segment OCT data.

The purpose of this study is to develop a straightforward mathematical concept for determination of object to image magnification in both phakic and pseudophakic eyes, based on biometric measures, refractometry and data from an anterior segment optical coherence tomography (OCT). We have developed a strategy for calculating ocular magnification based on axial length measurement, phakic anterior chamber and lens thickness, keratometry and crystalline lens front and back surface curvatures for the phakic eye, and axial length measurement, anterior chamber and lens thickness, keratometry and intraocular lens power, refractive index and shape factor for the pseudophakic eye. Comparing the magnification of both eyes of one individual yields aniseikonia, while comparing the preoperative and postoperative situation of one eye provides the gain or loss in ocular magnification. The applicability of this strategy is shown using a clinical example and a small case series in 78 eyes of 39 patients before and after cataract surgery. For the phakic eye, the refractive index of the crystalline lens was adjusted to balance the optical system. The pseudophakic eye is fully determined and we proposed three strategies for considering a potential mismatch of the data: (A) with spherical equivalent refraction, (B) with intraocular lens power and (C) with the shape factor of the lens. Magnification in the phakic eye was -0.00319±0.00014 and with (A) was -0.00327±0.00013, with (B) was -0.00323±0.00014 and with (C) was -0.00326±0.00013. With A/B/C, the magnification of the pseudophakic eye was on average 2.52±2.83%/1.31±2.84%/2.14±2.80% larger compared with the phakic eye. Magnification changes were within a range of ±10%. On average, ocular magnification does not change greatly after cataract surgery with implantation of an artificial lens, but in some cases, the change could be up to ±10%. If the changes are not consistent between the left and right eyes, then this could lead to post-cataract aniseikonia.

AIS data, a mine of information on trawling fleet mobility in the Mediterranean Sea

In the Mediterranean Sea, fishing vessels often operates throughout the geographical subdivisions adopted for statistical data collection (Geographical Sub-Areas; GSAs), causing a potential mismatch between catches site and reporting site. This paper provides a quantitative assessment of the fluxes of fishing activity of bottom trawlers across the Mediterranean Sea, by analyzing the Automatic Identification System (AIS) data broadcasted in 2017. Fishing activity was analyzed from three perspectives: fishing site, port of arrival and registration site of the vessel. For each GSA, a “fidelity score” was calculated to quantify the proportion of fishing time spent in the home GSA; an “intrusion score” was computed to quantify the effort deployed by vessels registered elsewhere. Major vessel fluxes were detected between GSAs, and fleets were classified based on their mobility. Areas showing fleet overlaps were identified and those characterized by the largest overlaps were selected as case studies. The lowest fidelity scores were observed in the central Mediterranean (GSAs 11.2, 15, 16 and 18), while the highest intrusion score was recorded in the southern Mediterranean and around Crete. The vessels responsible of the largest fluxes were those registered in GSAs 16, 18, and 6. The case studies included: GSAs 23, where several fleets exploited narrow slope areas; GSA 13, where multiple fleets overlapped in a relatively wide area; and GSA 17, where two fleets overlapped in a wide platform area. Mobility was distinguished in short-range – involving platform areas of contiguous GSAs – and long-range – involving slope areas of non-contiguous GSAs.

Genotype × Environment Interaction and Yield Stability of Large Speckled Common Bean (Phaseolus vulgaris L.) Genotypes in Ethiopia Using AMMI Analysis

Common beans are grown throughout Ethiopia and an increasingly important commodity in the cropping systems of smallholder producers both for food security and income. However, happening of significant genotype X environment interaction (GEI) complicates selection of stable genotypes. Nowadays, the yield potential of common bean is underutilized due to inadequate addressing of all potential areas and mismatch between selection and production environments. Thus, 17 large speckled common bean genotypes were evaluated at three locations (Bako, Billo and Gute) for two consecutive years to estimate the magnitude of GEI effects and to identify broadly or specifically adapted genotypes during 2015 and 2016 main cropping seasons. The genotypes were arranged in Randomized complete block design with three replications. Combined ANOVA, AMMI and GGE biplot models were used to analyze the data. Both main and interaction effects were highly significant (P<0.01) and environment, genotype, and GEI explained 49.8%, 25.1% and 20.0% variations, respectively, indicating greater influence of test environments and importance of simultaneous consideration of mean performance and stability. IPCA1 and IPCA2 were highly significant (p < 0.01) and together contributed more than 89.5% variation in the GEI sum of squares. AMMI 1 biplot enabled identification of broadly adapted genotypes, G 3 (DAB-443) and G 10 (DAB-364). GGE biplot analysis suggested presence of one mega-environment and enabled identification of high seed yielding and broadly adapted genotypes (DAB-449 (G4)). DOI: 10.7176/JNSR/12-9-03 Publication date: May 31 st 2021

Negative socio-environmental feedback loop may foster inequality for urban marine subsistence fishers

In a food-limited urban environment, policy can improve or exacerbate existing inequalities in access to natural resources. While urban marine subsistence fishers in the United States (US) commonly provision their diets using local fish, little is known about how local policy relates to subsistence fisher vulnerability and existing socioeconomic disadvantage. Further, it is unclear how US state agencies consider subsistence fisher practices or vulnerabilities in urban planning or biomonitoring. Data mismatches may prevent urban subsistence fishers from accessing adequate fisheries resources and making informed dietary choices, potentially leading to unhealthy fish consumption practices. We evaluated potential mismatches between marine subsistence fishing practices, fisheries policy, and urban planning by conducting a transdisciplinary synthesis of recreational fisheries surveys, fish biomonitoring data, socioeconomic data, and planning policy documents from New Orleans, Louisiana (US) and Tampa, Florida (US). Urban subsistence fishers represent a heterogeneous community whose diverse fishing practices were inadequately integrated into public policies. Further, we found an association between increased fishing levels and neighbourhood disadvantage. This misalignment between policy and practice may introduce unknown health risks for subsistence fishers. We make recommendations for broadening fisher characterization to include non-tribal subsistence fishing, utilizing more social science approaches in developing subsistence fishing policy, integrating fishing practices in urban policy and planning decisions, and increasing communication across agencies concerning policies affecting urban fishers.

The relationship between scale and predictor variables in species distribution models applied to conservation

Species distribution models have been used to assist decision-making in many different aspects of conservation, restoration, and environmental management. However, to apply species distribution models effectively, we need to discriminate between suitable and unsuitable environments and the models need to be developed at fine scales (i.e. covering small areas at a fine resolution). These characteristics allow more precise decision-making for heterogeneous environments in smaller areas, such as biomes. We also need to understand the potential limiting factors in relation to these models better, including the effects of sample bias in species occurrence records and the potential mismatch between the scale at which the models were built and the scale at which the predictor variables interact with species occurrence. Here we evaluate the effects of two methods used to reduce bias (geographic vs. environmental filters) and three predictor variable types (climactic, local and biotic) on model predictions. We explore these issues for the hyacinth macaw (Anodorhynchus hyacinthinus), a globally vulnerable species in the Pantanal biome of central South America. We consider broad-scale variables, local-scale habitat associations, and the interactions of the macaw with two plant species that provide its food and nesting location. Our results show that using broad-scale climate variables for local-scale models (i.e., models with a fine resolution with a small extent) can generate predictive distribution models that underpredict suitability. Using local and biotic variables generates more accurate models with predictions consistent with the known distribution of the bird species. Although not commonly used, local-scale variables strongly affect model performance by increasing accuracy, reducing omission error, and leading to more conservative predictions. On the other hand, these methods lead to variable results in relation to bias reduction, with their efficiency depending on the amount of sampling bias in the occurrence records. In conclusion, local variables and the method of bias reduction play an important role in species distribution models. Fine resolution models constructed at the local scale for small areas show the greatest skill in predicting species distribution.

Mismatch between jar opening demands and wrist torque strength of consumers in Iran

This study evaluated the potential mismatch between vacuum-sealed jar opening demands and wrist torque strength of 758 (384 males and 374 females) participants aged 5–74 years in Iran. Wrist ulnar/radial (U/R) torque strength of participants and required torque for opening the existing jars (with 2 different sizes – 65 mm and 85 mm diameter lids) were measured using a digital angle torque adaptor and then compared together to identify any potential mismatch between them. The mismatch percentages were defined as the number of participants whose maximal wrist U/R torque strength were lower than the minimum required torque strength for opening the vacuum-sealed jars. Minimum required torque strength for opening the existing 65 mm and 85 mm vacuum-sealed jars were 4.1 Nm and 6.6 Nm, respectively (range = 4.1 Nm to 10.2 Nm). A considerable mismatch (range = 25%–100%) was found between the required torque strength for opening the existing jars and the wrist U/R torque strength of the study population, particularly for females and those aged 5–9 years. A torque limit of 1.8 Nm was proposed for opening jars for the entire population.

The Semantic Field Theoretical Approach in the teaching of English and its Grammatical Implication to Second Language Development

The Semantic Field Theory (SFT) has been widely used in teaching English as a second Language to preschool children in Kenya. In the SFT approach, the grammars of two or more languages are in contact. The grammar of languages involved in the SFT approach may be similar or different. However, studies have indicated that where the grammar of two languages in contact differ, syntactic mismatches are likely to result. It was against this background that the investigation was undertaken to establish the potential syntactic mismatches between English and Lukabarasi when using the SMT approach and the possible grammatical implications to English language development lessons. Contrastive Analysis (CA) by Lado (1967) was used in the comparison of the structures of Lukabarasi and English in order to identify syntactic similarities and differences in The First Language (L1) and The Second Language (L2). A sample of 10 key informants teaching English as a second language in rural pre-schools were purposively sampled to help collect the songs. Two songs were purposively sampled for collecting the relevant data. Content analysis guided the data analysis to identify the parts of the songs that were relevant to the achievement of the research objective. The findings indicated that teachers used Lukabarasi songs during English development lessons to enhance vocabulary acquisition using the SFT approach. Further, rules of the two languages were not observed and finally, there were syntactic mismatches during the teaching of English lessons. The findings revealed that extensive use the SMT approach and failure to follow rules of languages during L2 lessons may affect second language development. The findings recommend use of SFT approach when necessary in teaching English and adherence to rules of the two languages during English lessons to reduce negative transfer and to enhance L2 development.

Assessing People’s Values of Nature: Where Is the Link to Sustainability Transformations?

The efforts to measure people’s current preferences and values of ecosystem services raise questions about the link to sustainability transformations. The importance of taking social and cultural values of nature into account is increasingly recognised within ecosystem services research and policy. This notion is informing the development and application of social (or socio-cultural) valuation methods that seek to assess and capture non-material social and cultural aspects of benefits of ecosystems in non-monetary terms. Here, ‘values’ refer to the products of descriptive scientific assessments of the links between human well-being and ecosystems. This precise use of the values term can be contrasted with normative modes of understanding values, as underlying beliefs and moral principles about what is good and right, which also influence science and institutions. While both perspectives on values are important for the biodiversity and ecosystem services agenda, values within this space have mainly been understood in relation to assessments and descriptive modes of values. Failing to acknowledge the distinction between descriptive and normative modes bypasses the potential mismatch between people’s current values and sustainability transformations. Refining methodologies to more accurately describe social values risks simply giving us a more detailed account of what we already know—people in general do not value nature enough. A central task for values studies is to explore why or how peoples’ mindsets might converge with sustainability goals, using methods that go beyond assessing current states to incorporate change and transformation.

Mismatched diets: defining the nutritional landscape of grasshopper communities in a variable environment

AbstractAnimal populations must be able to acquire an adequate amount of nutrients to persist regardless of what environment they are in. In highly variable environments, such as drylands where food sources are limited, this potential mismatch between physiological demands and what is available in the environment is accentuated. For herbivores, the balance of macronutrients (protein and carbohydrate) is particularly important and both nutrients are highly variable in plants both spatially and temporally. Whereas it is known that many herbivores will forage multiple plants to achieve an optimal nutritional ratio (termed the intake target), it is less known how herbivores with different life history strategies address this in variable environments. In this study, we measured the intake targets of three grasshopper species with differing life history strategies, two migratory and one non‐migratory, at three locations in New South Wales, Australia. We measured nutrient variation in plants spatially and temporally by sampling three different locations and repeated the measurement twice for one of these locations. At all three locations and both times, host plant protein differed substantially but carbohydrate content remained constant. The non‐migratory grasshopper species shifted their intake target, presumably to redress nutrient imbalances. On the other hand, the two migratory grasshopper species largely maintained the same intake target, even when in a nutritionally suboptimal environment. These results suggest that non‐migratory species are likely more limited in their capacity to forage for optimal diets and may rely more on digestion to survive in nutritionally suboptimal locations. In contrast, migratory grasshoppers may migrate to obtain the nutrients they need instead of redressing imbalances locally. Therefore, a strong metapopulation structure may aid in the persistence of migratory species at larger spatial scales. Since herbivores, especially insects, are important from nutrient cycling to food chains, understanding how populations persist in nutritionally variable environments is important to the overall ecosystem functioning. Further research should consider how nutritional demands drive population dynamics and how it changes with life history strategies.

Childhood Teaching and Learning among Savanna Pumé Hunter-Gatherers : Mismatch between Foraging and Postindustrial Societies.

Research in nonindustrial small-scale societies challenges the common perception that human childhood is universally characterized by a long period of intensive adult investment and dedicated instruction. Using return rate and time allocation data for the Savanna Pumé, a group of South American hunter-gatherers, age patterns in how children learn to become productive foragers and from whom they learn are observed across the transition from childhood to adolescence. Results show that Savanna Pumé children care for their siblings, are important economic contributors, learn by doing rather than by instruction, and spend their time principally in the company of other children. This developmental experience contrasts with that of children in postindustrial societies, who are dependent on adults, often well past maturity; learn in formal settings; and spend much of their time in the company of adults. These differences raise questions about whether normative behaviors observed in postindustrial societies are representative of human children. This comparison also identifies the potential mismatch between hunter-gatherer and postindustrial societies in the extent to which children may be well adapted to learn from and teach each other. In particular, spending time in autonomous work and play groups develops the cooperation and coordination skills that are foundational to human subsistence and growing up to be socially and productively adept adults and parents.

Regime changes and the impact of informal labor

Abstract In Israel, approximately 25,000 Thai laborers are contracted for agricultural work in all parts of the country, following a series of bilateral agreements between the governments of Israel and Thailand. Various NGOs and agencies have documented numerous violations of labor laws in many Israeli farms, including the lack of safety measures, poor working and living conditions, and extremely low salaries. Israeli discourse on the topic vacillates between the interests of farmers, workers, consumers, and the government (Or & Shohamy, 2020), and the occasional appearance of reports about the abuse of workers reignites the debate and tensions surrounding these issues. This longitudinal qualitative study, spanning from 2013 to 2019, focuses on the linguistic landscape (LL) of the Central Arava region – an arid, sparsely populated subdistrict in Southern Israel. What makes this region unique is that the number of Thai migrant workers there equals or slightly exceeds that of Hebrew-speaking Jews. Using an LL approach (Jaworski & Thurlow, 2010; Shohamy & Gorter, 2009; Shohamy, 2012), the 2013 study sought to explore the visibility and vitality of the Thai language as well as its interactions with other languages. The roles that Thai, Hebrew, English, Arabic, and other languages played in the public space clearly revealed the power relations between the speakers of these languages. The 2018–19 follow-up to the original 2013 findings seeks to track the impact on the public space of recent developments such as population changes, the advent of speakers of other languages to the region, the economic crisis, and the public controversy about the exploitation of workers. The study shows that the number of Thai signs has been significantly reduced in recent years, not only pointing to changes in the multilingual reality of the region, but also raising a series of questions about labor conditions, regulation, informal labor markets, and cases of potential mismatch between reality and perceptions.

Constructional idioms of ‘insanity’ in English and Spanish: A corpus-based study

This paper presents a corpus-based study of constructions in English and Spanish, with a special emphasis on equivalent semantic-functional counterparts, and potential mismatches. Although usage/corpus-based Construction Grammar (CxG) has attracted much attention in recent years, most studies have dealt exclusively with monolingual constructions. In this paper we will focus on two constructions that represent conventional ways to express ‘insanity’ in both languages. The analysis will cover grammatical, semantic and informative aspects in order to establish a multi-linguistic prototype of the constructions. To that end, data from several giga-token corpora of contemporary spoken English and Spanish (parallel and comparable) have been selected. This study advances the explanatory potential of constructional idioms for the study of idiomaticity, variability and cross-language analysis. In addition, relevant findings on the dialectal distribution of certain idiom features across both languages and their national varieties are also reported.

IUPACpal: efficient identification of inverted repeats in IUPAC-encoded DNA sequences

BackgroundAn inverted repeat is a DNA sequence followed downstream by its reverse complement, potentially with a gap in the centre. Inverted repeats are found in both prokaryotic and eukaryotic genomes and they have been linked with countless possible functions. Many international consortia provide a comprehensive description of common genetic variation making alternative sequence representations, such as IUPAC encoding, necessary for leveraging the full potential of such broad variation datasets.ResultsWe present IUPACpal, an exact tool for efficient identification of inverted repeats in IUPAC-encoded DNA sequences allowing also for potential mismatches and gaps in the inverted repeats.ConclusionWithin the parameters that were tested, our experimental results show that IUPACpal compares favourably to a similar application packaged with EMBOSS. We show that IUPACpal identifies many previously unidentified inverted repeats when compared with EMBOSS, and that this is also performed with orders of magnitude improved speed.

Latitudinal variation in arrival and breeding phenology of the pied flycatcher Ficedula hypoleuca using large‐scale citizen science data

Many species have advanced the timing of annual reproductive cycles in response to climatic warming, sometimes leading to asynchrony between trophic levels, with negative population consequences. Long‐distance migratory birds, reliant on short seasonal food pulses for breeding, are considered particularly susceptible to such disjunction because late arrival may preclude optimal timing of egg‐laying. It is unknown whether the relative timing of arrival and egg‐laying is sufficiently plastic, in time and space, to enable an adaptive response when arrival times change relative to local food resources. We used citizen science data, describing pied flycatcher Ficedula hypoleuca arrival and egg‐laying dates, to explore temporal (2013–2016) and spatial (across Great Britain) variation in the phenology of arrival, laying and their difference. To assess the long‐term trend in arrival and laying at a single location, we used data from a long‐term field study. The arrival‐laying interval was consistently shorter in the north, driven by the contrast between spatial variation in arrival date and spatial invariance in laying date. To understand whether a short arrival‐laying interval may have consequences for productivity, we assessed the association between this interval and clutch size. We found no statistically significant correlation between these two variables. To examine long‐term changes in arrival and laying dates, we focussed on a single location in southwestern England. Both dates of first male arrival and first egg laid in a season advanced since 1986, with no evidence of interval shortening. Together, our results demonstrate spatial and annual variation in the arrival‐laying interval, with no detected effect on fecundity. Thus, the interval from arrival to laying is likely dictated by spatially and temporally varying local conditions, suggesting these migrant birds may have the ability to adapt this interval to align with local conditions and mitigate potential mismatch impacts.

Seed dispersal as a search strategy: dynamic and fragmented landscapes select for multi-scale movement strategies in plants

BackgroundPlant dispersal is a critical factor driving ecological responses to global changes. Knowledge on the mechanisms of dispersal is rapidly advancing, but selective pressures responsible for the evolution of dispersal strategies remain elusive. Recent advances in animal movement ecology identified general strategies that may optimize efficiency in animal searches for food or habitat. Here we explore the potential for evolution of similar general movement strategies for plants.MethodsWe propose that seed dispersal in plants can be viewed as a strategic search for suitable habitat, where the probability of finding such locations has been optimized through evolution of appropriate dispersal kernels. Using model simulations, we demonstrate how dispersal strategies can optimize key dispersal trade-offs between finding habitat, avoiding kin competition, and colonizing new patches. These trade-offs depend strongly on the landscape, resulting in a tight link between optimal dispersal strategy and spatiotemporal habitat distribution.ResultsOur findings reveal that multi-scale seed dispersal strategies that combine a broad range of dispersal scales, including Lévy-like dispersal, are optimal across a wide range of dynamic and patchy landscapes. At the extremes, static and patchy landscapes select for dispersal strategies dominated by short distances, while uniform and highly unpredictable landscapes both select for dispersal strategies dominated by long distances.ConclusionsBy viewing plant seed dispersal as a strategic search for suitable habitat, we provide a reference framework for the analysis of plant dispersal data. Consideration of the entire dispersal kernel, including distances across the full range of scales, is key. This reference framework helps identify plant species’ dispersal strategies, the evolutionary forces determining these strategies and their ecological consequences, such as a potential mismatch between plant dispersal strategy and altered spatiotemporal habitat dynamics due to land use change. Our perspective opens up directions for future studies, including exploration of composite search behaviour and ‘informed searches’ in plant species with directed dispersal.

Supervising the PhD: identifying common mismatches in expectations between candidate and supervisor to improve research training outcomes

ABSTRACT The relationship between PhD candidate and supervisor influences successful candidate completion and helps maintain candidate satisfaction and mental health. We quantified potential mismatches between the PhD candidates’ and supervisors’ expectations as a potential mechanism that facilitates poor candidate experiences and research training outcomes based on a quantitative survey which including rank order and Likert responses. 114 PhD candidates and 52 supervisors in Australia ranked the importance of student attributes and outcomes at the beginning and end of candidature. In relation to specific attributes, supervisors indicated the level of guidance they expected to give the candidate, and candidates indicated the level of guidance they expected to receive. Candidates also report on whether different aspects of candidature influenced their mental well-being. Using rank correlation and multivariate regression statistics, we identified differences between candidates’ and supervisors’ perceived supervisor teaching responsibility and candidatures influence on mental well-being. Results indicate the majority of candidates were satisfied overall with their supervision, and find alignment of many expectations between both parties. Yet, candidates tended to have much higher expectations about achieving quantitative outcomes than supervisors. Supervisors believed they give more guidance to candidates than candidates perceive they received, and supervisors often only provided guidance when the candidate explicitly asked. Personal expectations and research progress significantly and negatively influenced over 50% of candidates’ mental well-being. Our results highlight the importance of candidates and supervisors explicitly communicating the responsibilities and expectations of the roles they play in helping candidates develop research skills. We provide four suggestions to supervisors that may be particularly effective at increasing communication, avoiding potential conflict and promoting candidate success and well-being.