Asymmetric Outcome Research Articles

Interspecific competition impacts the occupancy and range limits of two ptarmigan species along the elevation gradient in Norway

Many mountain species are expected to respond to climate change through upslope shifts of their range limits, but competition may restrict or alter this response. Under traditional range‐limit theory, it is expected that lower‐elevation species are better competitors than closely related higher‐elevation species. However, recent work finds that this prediction is often unmet. We investigated evidence for the impact of competition during breeding season on the elevational range limits of a pair of closely related bird species, willow ptarmigan Lagopus lagopus and rock ptarmigan L. muta, in mainland Norway. The species share overlapping ranges that loosely divide slightly upslope from the treeline ecotone, with willow ptarmigan generally occupying lower sites and rock ptarmigan occupying higher sites. We used multi‐species occupancy models to test four competing hypotheses for how competition may affect the range limit between willow ptarmigan and rock ptarmigan: 1) asymmetric competition that restricts the lower range limit of rock ptarmigan; 2) asymmetric competition that restricts the upper range limit of willow ptarmigan; 3) condition‐specific competition that restricts both species' range limits; and 4) range limits unaffected by competition. We found evidence for a negative pairwise interaction between the two species. Changes in interaction strength along the elevation gradient suggested evidence for condition‐specific competition. However, a strong positive correlation between rock ptarmigan and higher‐elevation habitat resulted in a highly asymmetric outcome, where the upper range limit of willow ptarmigan was restricted but rock ptarmigan occupancy was fairly independent of willow ptarmigan. This outcome is opposite to the prediction of traditional range‐limit theory and may suggest a greater climate threat to willow ptarmigan than has been previously projected. Thus, our results demonstrate the importance of considering biotic interactions at both the higher and lower ends of species' range limits along elevation gradients.

The Drosophila neuroblast polarity cycle at a glance.

Drosophila neural stem cells, or neuroblasts, rapidly proliferate during embryonic and larval development to populate the central nervous system. Neuroblasts divide asymmetrically to create cellular diversity, with each division producing one sibling cell that retains the neuroblast fate and another that differentiates into glia or neurons. This asymmetric outcome is mediated by the transient polarization of numerous factors to the cell cortex during mitosis. The powerful genetics and outstanding imaging tractability of the neuroblast make it an excellent model system for studying the mechanisms of cell polarity. This Cell Science at a Glance article and the accompanying poster explore the phases of the neuroblast polarity cycle and the regulatory circuits that control them. We discuss the key features of the cycle - the targeted recruitment of proteins to specific regions of the plasma membrane and multiple phases of highly dynamic actomyosin-dependent cortical flows that pattern both protein distribution and membrane structure.

Revisiting the asymmetric outcome of renewable and nonrenewable energy on environmental quality in South and East Asia: An application of a broad-spectrum approach

Hydropower renewable energy is known to be pro-environment: flexible and affordable. Above all, it is compatible with other energy frames and also with the policies that otherwise prove to be inimical towards its future. Where environmental stability is concerned it needs an assiduous study coupled with research by the policymakers to get around knowing the different perspectives of hydropower renewable energy. The study has taken nine different and diverse perspectives of hydropower renewable energy into account to stop the process of environmental degradation. EKC framework has been put to use in a case study of South and East Asia economies. Time period has been selected from 1975 to 2020 to measure the long-term impact. GMM model has been used for the panel estimation besides getting future dynamics. The results which have come about confirmed EKC in the selected countries. Non-renewable energy (coal and gas) had an adverse impact on environmental stability. However, switching towards hydropower renewable energy can mitigate these environmental losses. Empirical findings have proved that more use of clean energy production can bring about a considerable amount of environmental stability. Insofar as East Asia economies are considered they have reached the second stage of EKC with a turning point of $13844 (per capita income). This paper, therefore, suggests that the future depends upon renewable hydropower energies in South and East Asia economies. That being said, there appears to be a dire need to undertake the role of various socioeconomic and geographic factors that influence hydropower renewable energies to check the long-term effect.

Asymmetric Interaction Between Two Mycorrhizal Fungal Guilds and Consequences for the Establishment of Their Host Plants

Arbuscular mycorrhiza (AM) and ectomycorrhiza (EcM) are the most abundant and widespread types of mycorrhizal symbiosis, but there is little and sometimes conflicting information regarding the interaction between AM fungi (AMF) and EcM fungi (EcMF) in soils. Their competition for resources can be particularly relevant in successional ecosystems, which usually present a transition from AM-forming herbaceous vegetation to EcM-forming woody species. The aims of this study were to describe the interaction between mycorrhizal fungal communities associated with AM and EcM hosts naturally coexisting during primary succession on spoil banks and to evaluate how this interaction affects growth and mycorrhizal colonization of seedlings of both species. We conducted a greenhouse microcosm experiment with Betula pendula and Hieracium caespitosum as EcM and AM hosts, respectively. They were cultivated in three-compartment rhizoboxes. Two lateral compartments contained different combinations of both host plants as sources of fungal mycelia colonizing the middle compartment, where fungal biomass, diversity, and community composition as well as the growth of each host plant species’ seedlings were analyzed. The study’s main finding was an asymmetric outcome of the interaction between the two plant species: while H. caespitosum and associated AMF reduced the abundance of EcMF in soil, modified the composition of EcMF communities, and also tended to decrease growth and mycorrhizal colonization of B. pendula seedlings, the EcM host did not have such effects on AM plants and associated AMF. In the context of primary succession, these findings suggest that ruderal AM hosts could hinder the development of EcM tree seedlings, thus slowing the transition from AM-dominated to EcM-dominated vegetation in early successional stages.

The Price of Imposing Vertical Equity Through Asymmetric Outcome Constraints

Vertical equity or fairness is an important aspect in many settings, yet has received relatively little attention in the literature. Recent developments underline the practical relevance (e.g., COVID-19 vaccination policies). It plays an important role in the performance evaluation of many (nongovernmental) organizations. For example, donors might require a family-planning organization to allocate a minimum fraction of the total utility (client volume) to a particular player (the “high-impact” subgroup of the population, e.g., young and poor clients). However, the price (decrease in client volume) of such requirements is not well-understood. Consequently, this price is not accounted for in decision making. We provide an analytical upper bound on the price (i.e., loss of overall utility) of vertical equity considerations in resource allocation. We assume that these concerns are expressed via outcome constraints, specifying a minimum percentage of the total utility for each player. Our set-up considers a decision maker maximizing total utility over a general convex set, subject to outcome constraints. The set-up is general and applicable to many practical problems. Our results depend only on high-level parameters and are therefore well-suited for strategic decision making. We conclude with two applications. First, we apply our results to practical instances in health delivery. We confirm that outcome constraints can entail a substantial price and analyze the factors driving this price close to the worst-case bound. Second, we analyze how our results can help bound the impact of prioritization in vaccine allocation. This paper was accepted by Jeannette Song, operations management. Supplemental Material: Data files are available at https://doi.org/10.1287/mnsc.2021.4287 .

Revisiting the Asymmetric Outcome of Renewable and Nonrenewable Energy on Environmental Quality in South and East Asia: An Application of a Broad-Spectrum Approach

Revisiting the Asymmetric Outcome of Renewable and Nonrenewable Energy on Environmental Quality in South and East Asia: An Application of a Broad-Spectrum Approach

Characterization of histone inheritance patterns in the Drosophila female germline.

Stem cells have the unique ability to undergo asymmetric division which produces two daughter cells that are genetically identical, but commit to different cell fates. The loss of this balanced asymmetric outcome can lead to many diseases, including cancer and tissue dystrophy. Understanding this tightly regulated process is crucial in developing methods to treat these abnormalities. Here, we report that during a Drosophila female germline stem cell asymmetric division, the two daughter cells differentially inherit histones at key genes related to either maintaining the stem cell state or promoting differentiation, but not at constitutively active or silenced genes. We combine histone labeling with DNA Oligopaints to distinguish old versus new histones and visualize their inheritance patterns at a single‐gene resolution in asymmetrically dividing cells in vivo. This strategy can be applied to other biological systems involving cell fate change during development or tissue homeostasis in multicellular organisms.

External debt and economic growth in Pacific Island countries: A linear and nonlinear analysis of Fiji Islands

This paper studies the relationship between economic growth and external debt in Fiji between 1980 and 2018. Using the neoclassical growth framework and ARDL models, we trace out long run linear and nonlinear association among the variables. The results show that in the long-run linear measure of external debt has a negative effect on economic growth. A nonlinear analysis reveals an asymmetric outcome of external debt on economic growth. Export and total factor productivity as key economic control variables contribute significantly to economic growth. An alternative specification with exogenous domestic debt produces consistent asymmetric results. External debt exerts a more strong negative effect on growth compared to domestic debt as indebtedness increases. Threshold analysis confirms that public debt becomes a drag on growth beyond a certain point. It is emphasized that the government should tone down the unproductive expenditure and exercise greater objectivity in fiscal management to stabilize the debt.

Abstract P375: Cortical Venous Opacification Patterns and Outcome in Patients With Tandem Carotid Occlusion - Results From the ESCAPE NA1-Trial

Background: The degree of cortical venous opacification could reflect the degree of ischemia in tandem occlusions strokes. We assessed the association between asymmetric cortical vein opacification and outcome among patients with acute ischemic stroke and tandem occlusion. Methods: ESCAPE NA1 was a multicenter randomized-controlled trial comparing medical treatments nerinetide vs. placebo in patients with acute ischemic stroke and large vessel occlusion who underwent EVT. Tandem carotid occlusion was defined as complete occlusion of the ICA on catheter angiography. We assessed cortical venous opacification on baseline CTA using the COVES score (Jansen, et al. Radiology 2019, ranging from 0-6 with lower numbers indicating poor cortical venous filling, and dichotomized to 0 vs. 1-6). The influence of cortical venous opacification on functional outcome was analyzed using regression modelling with adjustment for age, baseline NIHSS and ASPECTS, thrombolysis and treatment allocation. Results: We assessed 115 patients with tandem occlusion. Median COVES score was 2 (IQR 1-3) with 9 patients (8%) scoring 0 (complete absence of cortical venous filling). Patients with COVES 0 were less likely to have good leptomeningeal collaterals (good collaterals: COVES 0: 0/9 (0%) vs. COVES 1-6: 19/102 (18%), p = 0.007). Patients with COVES 0 were less likely to achieve good outcome (mRS 0-2, COVES 0: 3/9 patients (33%) vs. COVES 1-6: 79/106 (74%), p=0.016). Cortical venous filling was significantly associated with good functional outcome on univariable analysis (OR 5.9, 95%CI 1.4 - 25.0), and after adjustment for baseline variables (OR 8.6, 95%CI 1.4 - 51.0). Cervical carotid angioplasty and/or stenting did not modify functional outcome after adjustment for COVES score. Conclusion: Impaired venous drainage is a marker of poor pial collaterals and is associated with poorer outcome in tandem occlusion patients.

The effect of grip position on golf driving accuracy and distance

ABSTRACT The grip position (GP) in golf substantially affects performance outcomes such as shot accuracy and hitting distance. However, it is unknown which specific GP (i.e., strong, neutral, weak) produces the desired shot outcomes. The current study investigated the impact of five systematically manipulated GPs using 15° increments between −30° (strong) and +30° (weak) on driving accuracy and distance. Data were collected using a Trackman™ doppler radar-based system for 28 amateur recreational golfers with a driver clubhead-speed range between 120 km/h and 153 km/h (M = 138.93 km/h, SD = 14.41) and a handicap range between −3 and −36 (M = −15.0, SD = 8.0). The results showed that GP significantly affected six dependent variables on accuracy (sideways deviation (left and right), accuracy absolute, clubface angle, club path angle, face to path angle, launch direction) and two outcomes on distance (clubhead speed and driving distance total). Overall, the optimal performance on driving accuracy and distance was found for the neutral and stronger GPs. Weaker GPs revealed significantly more adverse accuracy and distance effects. These results suggest asymmetric outcome effects of symmetrical GP manipulation. They also have practical implications for coaches and golfers intending to improve driving accuracy while maximizing driving distance.

Asymmetric Outcome Matching in Responders’ Disclosure of Successes and Failures

Asymmetric Outcome Matching in Responders’ Disclosure of Successes and Failures

Structures of ISCth4 transpososomes reveal the role of asymmetry in copy‐out/paste‐in DNA transposition

Copy‐out/paste‐in transposition is a major bacterial DNA mobility pathway. It contributes significantly to the emergence of antibiotic resistance, often by upregulating expression of downstream genes upon integration. Unlike other transposition pathways, it requires both asymmetric and symmetric strand transfer steps. Here, we report the first structural study of a copy‐out/paste‐in transposase and demonstrate its ability to catalyze all pathway steps in vitro. X‐ray structures of ISCth4 transposase, a member of the IS256 family of insertion sequences, bound to DNA substrates corresponding to three sequential steps in the reaction reveal an unusual asymmetric dimeric transpososome. During transposition, an array of N‐terminal domains binds a single transposon end while the catalytic domain moves to accommodate the varying substrates. These conformational changes control the path of DNA flanking the transposon end and the generation of DNA‐binding sites. Our results explain the asymmetric outcome of the initial strand transfer and show how DNA binding is modulated by the asymmetric transposase to allow the capture of a second transposon end and to integrate a circular intermediate.

Diagnosis by multimodal imaging in peripapillary pachychoroid syndrome: A case report

The case is reported of a 73-year-old male presenting with the recently described peripapillary pachychoroid syndrome. This syndrome is included in the pachychoroid diseases, which is a relatively new condition characterised by increased choroidal thickness with attenuation of the choriocapillary layer located above dilated choroidal vessels. It is associated with progressive malfunction of the retinal pigment epithelium and neovascularisation. The case is presented with a multimodal image, in which some tests show signs not previously described. In addition, a description is presented of the asymmetric outcome of both eyes after multiple treatments, since the left eye has a very severe affectation, and is refractory to the treatment.

Diagnóstico mediante imagen multimodal en síndrome paquicoroideo peripapilar: a propósito de un caso

The case is reported of a 73-year-old male presenting with the recently described peripapillary pachychoroid syndrome. This syndrome is included in the pachychoroid diseases, which is a relatively new condition characterised by increased choroidal thickness with attenuation of the choriocapillary layer located above dilated choroidal vessels. It is associated with progressive malfunction of the retinal pigment epithelium and neovascularisation. The case is presented with a multimodal image, in which some tests show signs not previously described. In addition, a description is presented of the asymmetric outcome of both eyes after multiple treatments, since the left eye has a very severe affectation, and is refractory to the treatment.

Social network analysis in pigs: impacts of significant dyads on general network and centrality parameters

In general, one animal is considered dominant over another animal if it has won more fights than its opponent. Whether this difference in won and lost fights is significant is neglected in most studies. Thus, the present study evaluates the impact of two different calculation methods for dyadic interactions with a significant asymmetric outcome on the results of social network analysis regarding agonistic interactions of pigs in three different mixing events (weaned piglets, fattening pigs and gilts). Directly after mixing, all animals were video recorded for 17 (fattening pigs, gilts) and 28 h (weaned piglets), documenting agonistic interactions. Two calculation methods for significant dyads, that is, dyadic interactions with a clear dominant subordinate relationship in which one animal has won significantly more fights than its encounter, were proposed: pen individual limits were calculated by a sign test considering the differences of won and lost fights of all dyadic interactions in each pen; dyad individual limits were determined by a one-sided sign test for each individual dyad. For all data sets (ALL, including all dyadic interactions; PEN or DYAD, including only significant dyads according to pen or dyad individual limits), networks were built based on the information of initiator and receiver with the pigs as nodes and the edges between them illustrating attacks. General network parameters describing the whole network structure and centrality parameters describing the position of each animal in the network were calculated. Both pen and dyad individual limits revealed only a small percentage of significant dyads for weaned piglets (12.4% or 8.8%), fattening pigs (4.2% or 0.6%) and gilts (3.6% or 0.4%). The comparison between the data sets revealed only high Spearman’s rank correlation coefficients (rS) for the density, that is, percentage of possible edges that were actually present in the network, whereas the centrality parameters showed only moderate rS values (0.37 to 0.75). Thus, the rank order of the animals changed due to the exclusion of insignificant dyads, which shows that the results obtained from social network analysis are clearly influenced if insignificant dyads are excluded from the analyses. Due to the fact that the pen individual limits consider the overall level of agonistic interactions within each pen, this calculation method should be preferred over the dyad individual limits. Otherwise, too many animals in the group became isolated nodes with zero centrality for which no statement about their position within the network can be made.

Impact of Significant Dyads on Dominance Indices in Pigs.

Simple SummaryInformation about the real dominance status of an animal is important to prevent misinterpretations about the social structure in animal groups. Thus, “one fight, won more” must not be interpreted as being dominant. Here, significant dyads help to answer the question of whether one animal is definitely dominant over another, and to clearly evaluate the social hierarchy within a group of animals. In the present study, two calculation methods for the determination of significant dyads in pigs are proposed: on the pen level, i.e., taking all fights in the pen into account, and on the dyad level, i.e., each dyad is considered individually. In three mixing events (weaned piglets, fattening pigs, gilts) the impact of significant dyads on dominance indices was calculated. The number of significant dyads was low but the rank order between the two different methods remained stable. Comparing both of the proposed methods, limits should be calculated on pen level due to the higher flexibility. Thus, significant dyads can be also determined in pens with a low number of fights. Dominance indices are calculated by considering the differences between the number of won and lost fights. Whether these differences show a significant asymmetric outcome or not is neglected. Thus, two calculation methods for the limits of significant dyads are proposed using a sign test based on the differences in won and lost fights, considering all dyadic interactions in the pen (PEN: pen individual limits), and a sign test focusing on each individual dyad (DYAD: dyad individual limits). These were compared to the data set containing all dyadic interactions (ALL). Agonistic interactions in three mixing events were video recorded for two and a half days (weaned piglets) or one and a half days (fattening pigs, gilts). Dominance indices (DI) were calculated for all data sets. Pen/dyad individual limits revealed a small number of significant dyads (weaned piglets: 12.4%/8.8%; fattening pigs: 4.2%/0.6%; gilts: 3.6%/0.4%). Pen individual limits should be selected as they allow adaption of the limits according to the fighting frequency. Spearman rank correlation coefficients of the dominance indices between the data sets were always above 0.7, implying that the rank order remained relatively stable. Information about the impact of significant dyads on sociometric measures is important to prevent misinterpretations about the social structure in animal groups and should be considered in future studies.

Sequential one-stage combined procedure for treating bilateral developmental hip dysplasia after walking age.

ObjectiveThis study aimed to evaluate outcomes of the sequential one-stage combined procedure for treating bilateral developmental dysplasia of the hip (DDH) that was diagnosed after walking age.MethodsThirty-five patients (70 hips) with late-presenting bilateral DDH were treated with the sequential one-stage combined procedure. Hips were reclassified according to the operative time and divided into the first and the second operated hips. The outcomes were compared clinically and radiographically between the two sides preoperatively and postoperatively.ResultsThe mean interval time between the two procedures was 5.9 months (range: 2–9 months). The first operated hip achieved better results than did the second operated hip. A total of 68.6% (24/35) of the patients in our series had an asymmetric outcome.ConclusionsThe sequential one-stage combined procedure is a challenge, but a reasonable alternative surgery for bilateral DDH in children after walking age. An asymmetric outcome is a special complication of this procedure.

Competing with co-created products

The practice of upstream firms (suppliers) and downstream firms co-creating products (goods or services) together has a long history in business markets. We analyze the strategic choices of two competing downstream firms who simultaneously decide whether or not to co-create with an upstream supplier. Within this framework we incorporate endogenous pricing and effort choices by the upstream supplier and the downstream firms. Downstream firms contemplating co-creation with a supplier are faced with a trade-off. On the one hand they can benefit from the supplier's innovation efforts and therefore obtain a better product. On the other hand, they are confronted with the adverse effect of their own innovation efforts spilling over to their rivals via the supplier who would sell the co-created product to all firms. Our model captures this tension and offers several insights.First, we show that all the channel members (the supplier and the firms) are getting higher profits when they all co-create together, as compared to the situation where there is no co-creation and the Supplier alone designs the product. However, we also demonstrate that the abovementioned trade-offs provide an incentive for firms to deviate from this outcome, sometimes resulting in no-co-creation between the downstream firms and upstream supplier in equilibrium.Further, we show that in the competitive co-creation environment, ex-ante symmetric firms may pursue asymmetric strategies in equilibrium. The asymmetric equilibrium, in which only one of the two firms co-creates with the supplier, is obtained when the degree of price sensitivity to competitor's product in the consumer market is moderate.Third, we find two types of asymmetric equilibria. For moderately low degrees of price sensitivity, all parties prefer the asymmetric outcome. For moderately high price sensitivity, both firms prefer co-creation, but the supplier will refuse to co-create with one of them thereby enforcing the asymmetric outcome. Thus, a strategic supplier's role is critical in that it expands the region where the asymmetric equilibrium takes place, beyond the one preferred by the firms themselves.We also show that, when firms compete in the end-consumer market, the supplier may exert lower innovation effort when it co-creates with two firms as compared to one. This is not the case in the absence of competition between the downstream firms.Finally, and counterintuitively, a higher degree of product fit for the rival can actually benefit the co-creating firm in the asymmetric outcome, even though it improves its rival's product.

Sequential Social Media Advertising: An Empirical Evidence

Social media platforms like Twitter and Facebook have emerged as new channels for advertising that enable customer targeting based on demographics, interests, and user behavior. Spillover within a social network plays a crucial role in social media marketing. Because individuals are part of multiple groups (based on their diversified interests) on social media, strategically sequencing ad campaigns across asymmetric groups can have an asymmetric outcome. In this paper, we present a theoretical model for information retention and show that the sequence order of advertisements across two target groups has distinct outcomes. This model is empirically tested through two online randomized field experiments that sequence social ads for a health services company and a consumer goods retailer. In both experiments, it is found that advertising first to a small group (i.e. target audience) followed by a large group performs better on all three platforms (Facebook, Instagram, and Twitter).

Cytokine receptor-Eb1 interaction couples cell polarity and fate during asymmetric cell division

Asymmetric stem cell division is a critical mechanism for balancing self-renewal and differentiation. Adult stem cells often orient their mitotic spindle to place one daughter inside the niche and the other outside of it to achieve asymmetric division. It remains unknown whether and how the niche may direct division orientation. Here we discover a novel and evolutionary conserved mechanism that couples cell polarity to cell fate. We show that the cytokine receptor homolog Dome, acting downstream of the niche-derived ligand Upd, directly binds to the microtubule-binding protein Eb1 to regulate spindle orientation in Drosophila male germline stem cells (GSCs). Dome's role in spindle orientation is entirely separable from its known function in self-renewal mediated by the JAK-STAT pathway. We propose that integration of two functions (cell polarity and fate) in a single receptor is a key mechanism to ensure an asymmetric outcome following cell division.