scholarly journals Plastic multicellular development of Myxococcus xanthus: genotype-environment interactions in a physical gradient

2018 ◽  
Author(s):  
Natsuko Rivera-Yoshida ◽  
Alejandro V. Arzola ◽  
Juan A. Arias Del Angel ◽  
Alessio Franci ◽  
Michael Travisano ◽  
...  

AbstractIn order to investigate the contribution of the physical environment to variation in multicellular development of Myxococcus xanthus, phenotypes developed by different genotypes in a gradient of substrate stiffness conditions were quantitatively characterized. Statistical analysis showed that plastic phenotypes result from the genotype, the substrate conditions and the interaction between them. Also, phenotypes were expressed with scale- and trait-specificity. Overall, the presented information highlights the constructive role of the physical context in the development of microbial multicellularity, with both ecological and evolutionary implications.

2019 ◽  
Vol 6 (3) ◽  
pp. 181730 ◽  
Author(s):  
Natsuko Rivera-Yoshida ◽  
Alejandro V. Arzola ◽  
Juan A. Arias Del Angel ◽  
Alessio Franci ◽  
Michael Travisano ◽  
...  

In order to investigate the contribution of the physical environment to variation in multicellular development ofMyxococcus xanthus, phenotypes developed by different genotypes in a gradient of substrate stiffness conditions were quantitatively characterized. Statistical analysis showed that plastic phenotypes result from the genotype, the substrate conditions and the interaction between them. Also, phenotypes were expressed in two distinguishable scales, the individual and the population levels, and the interaction with the environment showed scale and trait specificity. Overall, our results highlight the constructive role of the physical context in the development of microbial multicellularity, with both ecological and evolutionary implications.


Author(s):  
Matthew O. Jackson ◽  
Brian W. Rogers ◽  
Yves Zenou

What is the role of social networks in driving persistent differences between races and genders in education and labor market outcomes? What is the role of homophily in such differences? Why is such homophily seen even if it ends up with negative consequences in terms of labor markets? This chapter discusses social network analysis from the perspective of economics. The chapter is organized around the theme of externalities: the effects that one’s behavior has on others’ welfare. Externalities underlie the interdependencies that make networks interesting to social scientists. This chapter discusses network formation, as well as interactions between people’s behaviors within a given network, and the implications in a variety of settings. Finally, the chapter highlights some empirical challenges inherent in the statistical analysis of network-based data.


Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3271
Author(s):  
Agnieszka Izabela Baruk

The aim of this article was to identify the role of good mutual relationships with offerors for final purchasers, as well as define the meaning of the perception of offerors in the scope of listening to purchasers’ opinions and profiting from purchasers’ readiness to cooperate for the specificities of the prosumeric activity. A deep analysis of the world literature was used to prepare the theoretical part of this paper. The results of this analysis confirm the existing cognitive gap and research gap regarding mentioned aspects, including energy market. Empirical studies were conducted to reduce identified gaps. The survey method was used to collect primary data. The collected data were subjected to quantitative analysis, during which statistical analysis methods and tests were applied (Pearson chi-square independence test, V-Cramer factor analysis, Kruskal–Wallis test (KW), and exploratory factor analysis). The results of the statistical analysis and testing allowed the three research hypotheses formulated to be checked. Between the significance of good relationships with offerors and their perception, a statistically significant dependence was identified for all groups of offerors. The perception of offerors was a feature differentiating respondents’ opinions about the significance of good relationships with offerors for the two following groups: producers and traders. Additionally, the perception of offerors was a feature differentiating forms of prosumeric activity of respondents only for three interpurchase behaviors. The results obtained have a visible cognitive and applicability value. They contribute to the theory of marketing, as well as possibly facilitating the formation of good mutual relationships between offerors (including offerors of energy) and final purchasers as key partners cooperating with offerors in the marketing process. The approach presented in this paper has not been studied and analyzed so far, either in theoretical or in practical terms. This fact confirms its originality and value.


2021 ◽  
pp. 109634802110115
Author(s):  
Seonjeong (Ally) Lee ◽  
Ning-Kuang Chuang

The physical environment plays an essential role in customers’ hotel stay experiences. Hotels offer a differentiated atmosphere that creates favorable customers’ evaluations. Based on the significant role of environmental cues, this study investigates the effects of an expanded servicescape on customers’ evaluations, including customer satisfaction, quality of life, and customer loyalty, in the context of the hotel industry. To test the proposed research framework, this study collects data from previous hotel customers and conducts a self-administered, online survey. Findings identified ambience, interactions with employees, authenticity, and fascination positively influenced customers’ satisfaction, which further influenced customer loyalty. Only ambience and fascination positively influenced quality of life, which in turn influenced customer loyalty. Results contributed to the application of expanded servicescape in the hotel context. Results also suggested practical implications of the holistic approach of servicescape in the hotel industry.


2021 ◽  
Vol 108 (Supplement_2) ◽  
Author(s):  
A A Tahir ◽  
K M Ali ◽  
A U Khan ◽  
S Kamal ◽  
A Hussain ◽  
...  

Abstract Introduction Diverticular disease is a common health problem with a wide clinical spectrum. About 75% of the patients would have uncomplicated diverticulitis. Cornerstones of treatment are antibiotics, analgesia, and dietary advice. Recent evidence has shown that its treatment is controversial, questioning the use of antibiotics. Aim is to assess the role of antibiotics in the treatment of acute uncomplicated diverticulitis. Method This is a systematic review and Meta-analysis. Literature review of the available studies was conducted using search engines like Pubmed, Medline, Embase, Google Scholar, and Cochrane databases. Statistical analysis was conducted using RevMan5.4. Results Out of 1754 records 1324 were duplicates, 430 studies were screened. 395 were further excluded.35 full text articles were assessed and in the final review 10 studies were included. PRISMA guidelines were used. Pooled OR for recurrence = 0.92 (95% CI = 0.74 to 1.13). Pooled OR for Hospital stay= -0.66 (95% CI= -1.12 to -0.21). Pooled OR for complications = 1.06 (95% CI = 0.69 to 1.64). Pooled OR for treatment failure= 1.24 (95% CI = 0.90-1.69). Conclusions We conclude that from the available evidence antibiotics have no role in reducing recurrence, complications, treatment failure, and duration of hospital stay in acute uncomplicated diverticulitis.


2020 ◽  
Vol 32 (S1) ◽  
pp. 15-16
Author(s):  
William E. Reichman ◽  
L. Bradford Perkins ◽  
Hilde Verbeek

This symposium will review the latest data on the influence of environmental design and its attributes on the cognitive and psychological wellbeing of older adults living with dementia. The presenters will cover the myriad ways in which the physical environment of care can adapt to the changing demands of older adults with sensory, motor and cognitive deficits and foster optimal functioning and quality of life. The role of emerging technologies will also be reviewed as they complement the contribution of the design of the physical environment to the wellbeing of older adults with cognitive impairment. Information will be offered through a review of the existing research literature as well as case studies that illustrate the impact of environmental modification on fostering wellbeing and minimizing the emergence of the behavioral and psychological symptoms of dementia. The presenters will represent and integrate sensibilities that have emerged from the fields of architecture, cognitive neuroscience and psychology.How the Principles of the Culture Change Movement Inform Environmental Design and the Application of Technology in the Care of Older Adults Living with DementiaWilliam E. ReichmanThe culture change movement informs a number of principles that have been applied to more contemporary design concepts for the congregate care of older adults living with dementia. This talk will review the core tenets of the Culture Change Movement as exemplified by the Greenhouse, Dementia Village and other innovative models of congregate long-term care. Specific reference will be made to how these tenets have been operationalized around the world into the design of programming and the creation of residential care environments that foster a better quality of life for older adults and an enhanced work environment for care providers. This talk will also include the emerging role of technologies that complement innovative design of the environment and which foster optimized social and recreational functioning of older adults living with dementia.A Better Life Through a Better Nursing Home DesignL. Bradford PerkinsOver the last 20 years there has been extensive experimentation related to the role of the environment in the housing, care and treatment of persons with Alzheimer’s and other age related dementias. Prior to that time the typical housing and care environment was a locked unit in a skilled nursing or other restrictive senior living facility. In 1991 the Presbyterian Association on Aging in Western Pennsylvania opened Woodside Place on its Oakmont campus. This small 36 bed facility was designed to incorporate the latest research and care experience with persons suffering from these issues. This one small project, as well as the long post occupancy research led by Carnegie Mellon University, clearly demonstrated that individuals with Alzheimer’s and related forms of dementia could lead a healthier, happier, higher quality of life in a more residential, less restrictive environment. Not everything in this pioneering project worked, and five generations of living and care models have followed that have refined the ideas first demonstrated by Woodside Place. Bradford Perkins, whose firm designed Woodside Place and over 100 other related projects, will discuss what was learned from Woodside Place as well as the five generations of projects (and post occupancy research) that followed.Innovative dementia care environments as alternatives for traditional nursing homes: evidence and experiences from the NetherlandsHilde VerbeekKey goals of the dementia care environment focus on increasing autonomy, supporting independence and trying to enable one’s own lifestyle for as long as possible. To meet these goals, innovative, small-scale and homelike care environments have been developed that have radically changed the physical, social and organizational aspects of long-term care in the Netherlands. This presentation discusses various Dutch models that have implemented small-scale and homelike care environments, including green care farms, dementia village and citizen initiatives. The models reflect a common care concept, focusing on residents’ remaining strengths, providing opportunity for choice and aiming to sustain a sense of self and control. A small number of residents (usually 6 to 8) live together in a homelike environment and nursing staff are part of the household. Residents are encouraged to participate in daily household activities, emphasizing normalization of daily life with person-centred care. The physical environment resembles an archetypal home. This talk presents the scientific evidence on the impact and effects of these small-scale, homelike models on residents, their family caregivers and staff. Furthermore, the presentation will highlight working approaches and how these initiatives have positively influenced routine care across the long-term care spectrum.


2021 ◽  
Vol 33 (3) ◽  
pp. 264-315
Author(s):  
Briana Van Epps ◽  
Gerd Carling ◽  
Yair Sapir

This study addresses gender assignment in six North Scandinavian varieties with a three-gender system: Old Norse, Norwegian (Nynorsk), Old Swedish, Nysvenska, Jamtlandic, and Elfdalian. Focusing on gender variation and change, we investigate the role of various factors in gender change. Using the contemporary Swedish varieties Jamtlandic and Elfdalian as a basis, we compare gender assignment in other North Scandinavian languages, tracing the evolution back to Old Norse. The data consist of 1,300 concepts from all six languages coded for cognacy, gender, and morphological and semantic variation. Our statistical analysis shows that the most important factors in gender change are the Old Norse weak/strong inflection, Old Norse gender, animate/inanimate distinction, word frequency, and loan status. From Old Norse to modern languages, phonological assignment principles tend to weaken, due to the general loss of word-final endings. Feminine words are more susceptible to changing gender, and the tendency to lose the feminine is noticeable even in the varieties in our study upholding the three-gender system. Further, frequency is significantly correlated with unstable gender. In semantics, only the animate/inanimate distinction signifi-cantly predicts gender assignment and stability. In general, our study confirms the decay of the feminine gender in the Scandinavian branch of Germanic.


1991 ◽  
Vol 115 (5) ◽  
pp. 1267-1274 ◽  
Author(s):  
S Eliott ◽  
P H Vardy ◽  
K L Williams

While the role of myosin II in muscle contraction has been well characterized, less is known about the role of myosin II in non-muscle cells. Recent molecular genetic experiments on Dictyostelium discoideum show that myosin II is necessary for cytokinesis and multicellular development. Here we use immunofluorescence microscopy with monoclonal and polyclonal antimyosin antibodies to visualize myosin II in cells of the multicellular D. discoideum slug. A subpopulation of peripheral and anterior cells label brightly with antimyosin II antibodies, and many of these cells display a polarized intracellular distribution of myosin II. Other cells in the slug label less brightly and their cytoplasm displays a more homogeneous distribution of myosin II. These results provide insight into cell motility within a three-dimensional tissue and they are discussed in relation to the possible roles of myosin II in multicellular development.


2000 ◽  
Vol 22 (2) ◽  
pp. 209-228 ◽  
Author(s):  
John C. Paolillo

Felix (1988) claimed to demonstrate that UG-based knowledge of grammaticality causes nonnative speakers (NNSs) to have more accurate grammaticality judgments on sentences that are ungrammatical according to UG than on those that are grammatical. Birdsong (1994) criticized the methodology employed, noting that it ignores “response bias” (a propensity to judge sentences as ungrammatical) as a potential explanation. Felix and Zobl (1994) dismissed this criticism as merely methodological. In this paper, Birdsong's criticism is upheld by considering a statistical model of the data. At the same time, a more complete logistic regression model allows a fuller statistical analysis, revealing tentative support for the asymmetry claim, as well as differential learning states for different constructions and a tendency toward transfer avoidance. These theoretically significant effects were unnoticed in the earlier discussion of this research. For SLA research on grammaticality judgments to proceed fruitfully, appropriate statistical models need to be considered in designing the research.


2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Bandana Sharma ◽  
Neetu Singh ◽  
Neena Gupta ◽  
Pavika Lal ◽  
Shefali Pande ◽  
...  

Objectives. To evaluate the role of angiogenesis tumor marker CD31 in the detection of precancerous and cancerous cervical lesions and to compare its efficacy with colposcopy and histopathology. Materials and Methods. 230 patients with a suspicious looking cervix and an abnormal Pap smear attending the Outpatient Department of Obstetrics and Gynaecology of GSVM Medical College were subjected to a colposcopic examination. 180 patients with suspected colposcopic findings were subjected to a colposcopic directed biopsy. Biopsy tissues were sent for histopathological examination out of which 50 biopsied samples were sent for immunostaining of CD-31. Statistical analysis was done. Results. Comparison of microvessel density (MVD) count by haematoxylin and eosin staining (HE) and immunostaining of CD31 in preinvasive group were and , respectively, and in invasive group were and , respectively, which showed that MVD was higher by CD31 both in preinvasive and invasive group, and it was statistically significant. Conclusion. Angiogenesis is a marker of tumor progression, and CD31 fixes up vessel better as compared to HE, so aggressiveness of the tumor can be better predicted by MVD-CD31 as compared to MVD-HE.


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