disruptive effect
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2021 ◽  
Author(s):  
A.V. Kalpadakis-Smith ◽  
V.K. Tailor ◽  
A.H. Dahlmann-Noor ◽  
J.A. Greenwood

AbstractVisual crowding is the disruptive effect of clutter on object recognition. Although most prominent in adult peripheral vision, crowding also disrupts foveal vision in typically-developing children and those with strabismic amblyopia. Do these crowding effects share the same mechanism? Here we exploit observations that crowded errors in peripheral vision are not random: target objects appear either averaged with the flankers (assimilation), or replaced by them (substitution). If amblyopic and developmental crowding share the same mechanism then their errors should be similarly systematic. We tested foveal vision in children aged 3-9 years with typical vision or strabismic amblyopia, and peripheral vision in adults. The perceptual effects of crowding were measured by requiring observers to adjust a reference stimulus to match the perceived orientation of a target ‘Vac-Man’ element. When the target was surrounded by flankers that differed by ±30°, adults and children reported orientations between the target and flankers (assimilation). Errors were reduced with ±90° differences, but primarily matched the flanker orientation (substitution) when they did occur. A population pooling model of crowding successfully simulated this pattern of errors in all three groups. We conclude that the perceptual effects of amblyopic and developing crowding are systematic and resemble the near periphery in adults, suggesting a common underlying mechanism.


Author(s):  
Tom Ondicho

As the end of the year 2021 draws near, it is time to reflect and take stock as well as look into the future. This year like 2020 was equally tough as the coronavirus (COVID-19) pandemic continues to wreak havoc in the world. The mortality and morbidity rates remain high despite the development of a vaccine and many people being vaccinated. New variants of the virus emerged in 2021 leading to renewed restrictions on businesses and internal mobility as well as international travel to some parts of the world. No doubt, the pandemic has had a cascading disruptive effect on all facets of life and continues to impact on people’s mental health, and academic being a stressful career than others, scholars need to do what they can to take care of their mental health and wellbeing during this period. This can involve simple steps such as taking a few days off to relax or to connect with family and friends. I hope you have started planning and hopefully, we have learned some lessons from 2020 and 2021 and will be better prepared and equipped to adjust to whatever the ‘New Normal’ has in store for us in 2022.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Clémence Lopez ◽  
Laurence Vaivre-Douret

AbstractHandwriting disorders (HD) are considered one of the major public health problems among school-aged children worldwide with significant interference on academic performances. The current study hypothesized that HD could be partly explained by a deficit in sensory feedback processing during handwriting. To explore this hypothesis, we have analyzed the effect of vision suppression on postural-gestural and on spatial/temporal/kinematic organization of drawing during an early pre-scriptural loop task with a digital pen, under two conditions: eyes open and eyes closed. Data collected from 35 children with HD were compared to data collected from typical children (typical group) from primary schools. The HD group showed significantly poorer postural control and an improvement on the spatial/temporal/kinematic organization of drawings when they closed their eyes compared to eyes opened. While in the typical group, postural-gestural organization became significantly more mature but there was no significant influence found on spatial/temporal/kinematic parameters of the loops. Thus, handwriting disorders could be explained by both proprioceptive/kinesthetic feedback disabilities and a disruptive effect of the visual control on the quality of the pre-scriptural drawings among these children who have kinesthetic memory and visuospatial disabilities. The ability of directing the strokes would remain dependent on sensory feedbacks, themselves insufficiently efficient, which would lead to difficulties in reaching a proactive control of handwriting. This current research is a liable contribution to enhance clinical practice, useful in clinical decision-making processes for handwriting disorders remediation.


2021 ◽  
Vol 8 (12) ◽  
Author(s):  
Sonja Wedmann ◽  
Petr Kment ◽  
Luiz Alexandre Campos ◽  
Thomas Hörnschemeyer

Newly discovered fossil bugs (Insecta: Hemiptera: Heteroptera: Pentatomidae) from the Eocene of Messel (Germany) and Green River (North America) exhibit an exaggerated morphology including prominent spiny humeral and anterolateral angles of the pronotum and a spiny lateral abdominal margin. Especially the humeral angles are unique; they consist of expansive, rounded projections with strong spines, which is a rare trait among pentatomids. A hypothesis for the function of this extreme morphology is defence against small vertebrate predators, such as birds or reptiles. The same protuberances also produce a disruptive effect camouflaging the specimen in its environment and provide additional protection. Therefore, the extreme morphology provides primary as well as secondary anti-predator defence. The morphology of Eospinosus peterkulkai gen. et sp. nov. and E. greenriverensis sp. nov. resembles that of Triplatygini, which today occur exclusively in Madagascar, as well as that of Discocephalinae or Cyrtocorinae, which today occur in the Neotropics. Due to a lack of conclusive characters, it cannot be excluded that the fossil species may represent a case of remarkable convergence and are not related to either taxon. Phylogenetic analyses using parsimony as well as Bayesian algorithms confirmed that the new genus is a member of Pentatomidae, but could not solve its phylogenetic relationships within Pentatomidae.


2021 ◽  
Vol 58 (1&2) ◽  
pp. 214-240
Author(s):  
Adrian Mendoza

This paper provides an early assessment of global value chains (GVCs) amid the disruptive effects of COVID-19 on world trade. Using the Asian Development Bank’s updated Multiregional Input-Output Table, key indicators were estimated to identify important stylized facts about the contraction of GVC activities in 2020. Econometric models were also estimated to analyze the disruptive effect of COVID-19 outbreaks and stringent containment measures on GVC trade. The input-output analysis confirms that all major economic sectors suffered large losses, especially services. However, the bulk of the decline in overall GVC trade can still be traced to lower backward transactions in manufacturing. On the aggregate level, stronger backward GVC participation was associated with relatively milder contraction while the opposite was observed for forward participation. The regressions showed that positive growth of GVC trade was less likely in sectors with relatively larger exposure to foreign downstream shocks. Further, the combined effects of stringent containment measures and severe COVID-19 outbreaks also reduced the probability of growth in both backward and forward GVC transactions. These findings indicate that on top of foreign suppliers’ internal disruptions (foreign supply shock), weak global consumption (foreign demand shock) and local producers’ domestic sourcing problems (local supply shock) contributed to the steep contraction of GVCs in 2020. Against this background, the major challenges to robust recovery were also identified. These include the downside risks of a prolonged pandemic, the resurgence of protectionist tendencies, the strength of global demand, the reconfiguration of broken supply chains, and the ability of countries to coordinate their actions especially with respect to vaccination.


2021 ◽  
Vol 15 (11) ◽  
pp. 1653-1660
Author(s):  
Nada Yasein ◽  
Wejdan Shroukh ◽  
Farihan Barghouti ◽  
Omayma Hassanin ◽  
Hala Yousef ◽  
...  

Introduction: Educational interventions targeting health care professionals can contribute to improving knowledge and behaviors of antimicrobial agents prescribing. However, the unprecedented COVID-19 outbreak caused a disruption of the current practices and treatment guidelines. Therefore, it is highly likely that the pandemic had its disruptive effect on any educational interventions that were going on during the outbreak. This study aims to evaluate the effectiveness of an educational intervention in improving antimicrobial agents prescribing Methodology: This was a randomized controlled study that included 69 resident physicians in a teaching hospital. The intervention group received an educational intervention focusing on antimicrobial agents prescribing and resistance. Before and after the intervention, outpatient antimicrobial agents prescribing rates for the two study arms were compared for the pre- and post-intervention periods. Additionally, all participants were asked to complete an online questionnaire that measured their knowledge, attitudes and behavioral intention towards antimicrobial agents resistance and prescription. The post-intervention period included the months of February, March, and June 2020. April and May were excluded from the study period since clinics were closed due to the COVID -19 pandemic. Results: Post-intervention, the rate of antimicrobial agents prescribing by the intervention group was significantly higher than that of the control group (p < 0.001). Mean fear score for the intervention group was significantly lower than that for the control group after the intervention. Conclusions: Findings indicate failure of the educational intervention in improving antimicrobial agents prescribing. However, an unexpected counter effect of the COVID-19 outbreak is highly likely.


2021 ◽  
Author(s):  
Nadee Sheresha Surangi Hapugoda Achchi Kankanamge

Abstract This study goes on to expand on current knowledge through the way it accounts for how female entrepreneurs form and develop their networks in the Sri Lankan context. It adopts social constructionism philosophy and narrative design to explore the female entrepreneurs' networking behaviour. Thematic analysis is used to understand the life stories of fourteen women entrepreneurs in the tourism sector. Findings suggest that female entrepreneurs are likely to rely on more informal recruitment methods and informal training practices. They have strong relationships with local communities, but they focus on customers beyond the locals. Seasonality within tourism has been the emphasis of tourism literature due to its disruptive effect on economic transactions. However, less of the literature has examined the social effects of seasonality, which is where this study can contribute by exploring how gender roles related to social and domestic responsibilities are renegotiated during the low and high seasons when tourism entrepreneurs re-adjust to new time-demand realities. Yet, the narrative research design is not widely used in the Sri Lankan context. Therefore, this article attempts to add to the entrepreneurial networking knowledge by analyzing stories towards female entrepreneurs' experience and social constructionist perspective.


2021 ◽  
Author(s):  
Xavier Didelot ◽  
Julian Parkhill

Recent years have seen a remarkable increase in the practicality of sequencing whole genomes from large numbers of bacterial isolates. The availability of this data has huge potential to deliver new insights into the evolution and epidemiology of bacterial pathogens, but the scalability of the analytical methodology has been lagging behind that of the sequencing technology. Here we present a step-by-step approach for such large-scale genomic epidemiology analyses, from bacterial genomes to epidemiological interpretations. A central component of this approach is the dated phylogeny, which is a phylogenetic tree with branch lengths measured in units of time. The construction of dated phylogenies from bacterial genomic data needs to account for the disruptive effect of recombination on phylogenetic relationships, and we describe how this can be achieved. Dated phylogenies can then be used to perform fine-scale or large-scale epidemiological analyses, depending on the proportion of cases for which genomes are available. A key feature of this approach is computational scalability, and in particular the ability to process hundreds or thousands of genomes within a matter of hours. This is a clear advantage of the step-by-step approach described here. We discuss other advantages and disadvantages of the approach, as well as potential improvements and avenues for future research.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1877
Author(s):  
Martin Hsiu-Chu Lin ◽  
Li-Ching Chang ◽  
Chiu-Yen Chung ◽  
Wei-Chao Huang ◽  
Ming-Hsueh Lee ◽  
...  

Glioblastoma multiforme (GBM) is the most common malignant primary neoplasm of the adult central nervous system originating from glial cells. The prognosis of those affected by GBM has remained poor despite advances in surgery, chemotherapy, and radiotherapy. Photochemical internalization (PCI) is a release mechanism of endocytosed therapeutics into the cytoplasm, which relies on the membrane disruptive effect of light-activated photosensitizers. In this study, phototherapy by PCI was performed on a human GBM cell-line using the topoisomerase II inhibitor etoposide (Etop) and the photosensitizer protoporphyrin IX (PpIX) loaded in nanospheres (Ns) made from generation-5 polyamidoamine dendrimers (PAMAM(G5)). The resultant formulation, Etop/PpIX-PAMAM(G5) Ns, measured 217.4 ± 2.9 nm in diameter and 40.5 ± 1.3 mV in charge. Confocal microscopy demonstrated PpIX fluorescence within the endo-lysosomal compartment, and an almost twofold increase in cellular uptake compared to free PpIX by flow cytometry. Phototherapy with 3 min and 5 min light illumination resulted in a greater extent of synergism than with co-administered Etop and PpIX; notably, antagonism was observed without light illumination. Mechanistically, significant increases in oxidative stress and apoptosis were observed with Etop/PpIX-PAMAM(G5) Ns upon 5 min of light illumination in comparison to treatment with either of the agents alone. In conclusion, simultaneous delivery and endo-lysosomal co-localization of Etop and PpIX by PAMAM(G5) Ns leads to a synergistic effect by phototherapy; in addition, the finding of antagonism without light illumination can be advantageous in lowering the dark toxicity and improving photo-selectivity.


Author(s):  
Florian Packmor ◽  
Dmitry Kishkinev ◽  
Flora Bittermann ◽  
Barbara Kofler ◽  
Clara Machowetz ◽  
...  

For studies on magnetic compass orientation and navigation performance in small bird species, controlled experiments with orientation cages inside an electromagnetic coil system are the most prominent methodological paradigm. These are, however, not applicable when studying larger bird species and/or orientation behaviour during free flight. For this, researchers have followed a very different approach. By attaching small magnets to birds, they intended to deprive them of access to meaningful magnetic information. Unfortunately, results from studies using this approach appear rather inconsistent. As these are based on experiments with birds under free flight conditions, which usually do not allow exclusion of other potential orientation cues, an assessment of the overall efficacy of this approach is difficult to conduct. Here, we directly test the efficacy of small magnets for temporarily disrupting magnetic compass orientation in small migratory songbirds using orientation cages under controlled experimental conditions. We found that birds which have access to the Earth's magnetic field as their sole orientation cue show a general orientation towards their seasonally appropriate migratory direction. When carrying magnets on their forehead under these conditions, the same birds become disoriented. However, under changed conditions that allow birds access to other (i.e. celestial) orientation cues, any disruptive effect of the magnets they carry appears obscured. Our results provide clear evidence for the efficacy of the magnet approach for temporarily disrupting magnetic compass orientation in birds, but also reveal its limitations for application in experiments under free flight conditions.


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