Recurrent speciation rates on islands decline with species number

2021 ◽  
Vol 288 (1949) ◽  
Author(s):  
Ryo Yamaguchi ◽  
Yoh Iwasa ◽  
Yuuya Tachiki
Keyword(s):  
Population Size ◽  
Species Number ◽  
Source Population ◽  
Research Attention ◽  
Number Of Species ◽  
Speciation Rates ◽  
Proportional Relationship ◽  
And Migration ◽  
The Impact

In an archipelagic system, species diversity is maintained and determined by the balance among speciation, extinction and migration. As the number of species increases, the average population size of each species decreases, and the extinction likelihood of any given species grows. By contrast, the role of reduced population size in geographic speciation has received comparatively less research attention. Here, to study the rate of recurrent speciation, we adopted a simple multi-species two-island model and considered symmetric interspecific competition on each island. As the number of species increases on an island, the competition intensifies, and the size of the resident population decreases. By contrast, the number of migrants is likely to exhibit a weaker than proportional relationship with the size of the source population due to rare oceanic dispersal. If this is the case, as the number of species on the recipient island increases, the impact of migration strengthens and decelerates the occurrence of further speciation events. According to our analyses, the number of species can be stabilized at a finite level, even in the absence of extinction.

scholarly journals ГЕОГРАФІЧНА СТРУКТУРА УРБАНОФЛОР СТЕПОВОЇ ЗОНИ УКРАЇНИ

2016 ◽  
Vol 6 (2) ◽  
pp. 239-245
Author(s):  
G. G. Derevyanska ◽  
O. Z. Glukhov
Keyword(s):  
Great Influence ◽  
Steppe Zone ◽  
Significant Heterogeneity ◽  
Geographic Ranges ◽  
Urban Flora ◽  
Adventive Species ◽  
Number Of Species ◽  
The Impact ◽  
Transition Type

<p>This paper considers the problem of geographic links between the urban flora of steppe zone of Ukraine on the example of the industrial agglomeration Donetsk-Makeyevka, in comparison with urban flora of Kherson and Kirovograd. We presented the detailed description of special features of the composition of geographic elements of the agglomeration flora. It strongly reflects the characteristic features of steppe urban flora, because its territory is affected by the anthropogenic influence at large extend. The spectrum of geographic ranges of species from the agglomeration Donetsk-Makeyevka urban flora numbers 6 types, 12 classes and 130 groups of ranges. The urban flora is both represented by species with wide and local ranges, endemics, that point to its significant heterogeneity. However, compared to the flora of Kherson and Kirovograd, the role of holarctic type of ranges in the agglomeration flora (375 species compared to 400 and 522 species, respectively) is reduced in favor of the polyregional type, reflecting active adventization processes. The holarctic class itself is represented by 150 species (16.7%). It far exceeds the number of species of this class in the regional flora (9.2%), since nearly a half of their number in the observed flora is adventive species. Second place by the number of species in the holarctic class belongs to the European and North American group (13; 1.5%). Apart from this, seven more groups of the class, comprising 1-3 species each, are connected with North America. The polyregional type is represented to a large extent by the species of ruderal habitats. The total number of species of this type is 199. The palaearctic class includes the greatest number of ranges of species from the agglomeration urban flora (31); it consists of 175 species (19.5%), that is less than such index for regional flora (27.3%). The European and Old Mediterranean transition type comprises 97 species (10.8%), that is less than in other urban flora of steppe zone (128; 13.3% in Kherson and 171; 18.0% in Kirovograd). The Nomadic type numbers 132 species (14.7%). One more species – Verbascum marschallianum Ivanina et Tzvelev – is related to the Nomadic and European transition type. The Nomadic and Old Mediterranean transition type includes 93 species (10.4%). This all suggests heterogeneity of urban flora of steppe zone of Ukraine due to their wide geographic connections. On the one hand, they have features of regional flora, which was formed under the great influence of Old Mediterranean flora and has a significant number of narrow-range and endemic species. On the other hand, under the impact of urbanization one can observe the reduction of the role of ranges of the Nomadic type and the enhanced role of the polyregional type due to the significant number of adventive species.</p><p> </p>

scholarly journals Understanding EU Solidarity and Migration in Crisis: Narratives of Health as Tools of Governance

2019 ◽  
Vol 10 (4) ◽  
pp. 677-692
Author(s):  
Rachael DICKSON
Keyword(s):  
Policy Development ◽  
Migration Policy ◽  
The European Union ◽  
Migration System ◽  
Migration Crisis ◽  
Crisis Narratives ◽  
And Migration ◽  
The Impact ◽  
European Migration

The so-called European migration crisis has sparked significant attention from scholars and raises questions about the role of solidarity between states and the European Union (EU) in providing policy solutions. Tension exists between upholding the rights of those seeking entry and pooling resources between Member States to provide a fair and efficient migration system. This article deconstructs the shifts that have occurred in EU migration policy since 2015 to highlight how narratives of health have become tools of governance. It does so to illuminate how health narratives operate to minimise the impact that conflicts on the nature and substance of EU solidarity have on policy development in response to the perceived crisis. A governmentality lens is used to analyse the implications of increasingly prescribed policy applications based on screening and categorising, and how measures operate to responsibilise migrants and third-countries to act according to EU values. It is argued this approach to governance results in migrants facing legal uncertainty in terms of accessing their rights and excludes them from the EU political space, which is problematic for how EU governance can be understood.

scholarly journals Building Customer Loyalty in Intercultural Service Encounters: The Role of Service Employees’ Cultural Intelligence

2019 ◽  
Vol 27 (2) ◽  
pp. 56-75 ◽  
Author(s):  
Nicholas G. Paparoidamis ◽  
Huong Thi Thanh Tran ◽  
Constantinos N. Leonidou
Keyword(s):  
Service Quality ◽  
Customer Loyalty ◽  
Cultural Intelligence ◽  
Emerging Market ◽  
Theory And Practice ◽  
Service Encounters ◽  
Research Attention ◽  
Service Employees ◽  
The Impact

Intercultural service encounters, in which customers and service employees from different cultures interact, are becoming more common in the market. Despite the importance of such encounters for international marketers, limited research attention has been directed to this area. Drawing on social exchange theory, this study examines how frontline employees’ cultural intelligence (CQ) influences customer loyalty outcomes of service quality perceptions. Specifically, the authors propose that the three components of CQ—cognitive, emotional/motivational, and physical—have differential moderating effects on the perceived service quality (PSQ)–customer loyalty link and that these effects vary across two national markets. Data collected with a multirespondent (i.e., frontline service employees and customers) cross-cultural research design indicate that cognitive CQ negatively mitigates the impact of PSQ on customer loyalty in an emerging-market context while emotional/motivational CQ has a positive moderating effect in a mature-market setting. When service employees have high physical CQ, the positive role of PSQ in creating and maintaining customer loyalty is strengthened in both markets. The authors discuss these implications for theory and practice.

scholarly journals Role of Anillin in Tumour: From a Prognostic Biomarker to a Novel Target

Cancers ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1600
Author(s):  
Nguyen Minh Tuan ◽  
Chang Hoon Lee
Keyword(s):  
Prognostic Biomarker ◽  
Tumour Microenvironment ◽  
Vital Role ◽  
Actin Binding ◽  
Cell Proliferation And Migration ◽  
Novel Target ◽  
And Migration ◽  
The Impact ◽  
Proliferation And Migration

Anillin (ANLN), an actin-binding protein, reportedly plays a vital role in cell proliferation and migration, particularly in cytokinesis. Although there have been findings pointing to a contribution of ANLN to the development of cancer, the association of ANLN to cancer remains not fully understood. Here, we gather evidence to determine the applicability of ANLN as a prognostic tool for some types of cancer, and the impact that ANLN has on the hallmarks of cancer. We searched academic repositories including PubMed and Google Scholar to find and review studies related to cancer and ANLN. The conclusion is that ANLN could be a potent target for cancer treatment, but the roles ANLN, other than in cytokinesis and its influence on tumour microenvironment remodeling in cancer development, must be further elucidated, and specific ANLN inhibitors should be found.

Effect of Temperature on Butterfly Community (lepidoptera) at Gunung Meja Recreational Forest Area, Manokwari, Papua Barat

2016 ◽  
Vol 1 (1) ◽  
Author(s):  
Rawati Panjaitan
Keyword(s):  
Secondary Forest ◽  
Environmental Parameters ◽  
Forest Area ◽  
Effect Of Temperature ◽  
Species Number ◽  
Primary Forest ◽  
Residential Areas ◽  
Number Of Species ◽  
Butterfly Community ◽  
The Impact

<p>Gunung Meja is one of the forest areas in Manokwari, West Papua province. It has been designated as a recreational forest since 1980. Gunung Meja covers 460.25 ha and is located at 75–175 m a.s.l. Gunung Meja is directly adjacent to residential areas, therefore the community activities, such as felling trees and gardening, was conducted in the area frequently. These can interfered the existence of flora and fauna in the area, included butterflies. To reveal the impact of intrusive human activities on the forest area, it was necessary to obtain basic information about what flora and fauna are present there. This study was aim to record the butterfly community in the area. Observations of butterflies were done by scan sampling on primary forest, secondary forest, gardens and settlements. Sampling and measurement of environmental parameters were performed in the morning and afternoon for seven weeks. This study recorded 113 species and 4.049 individuals of butterflies. There were 75 species in primary forest, 77 species in secondary forest, and 63 species in gardens and settlements. The number of species found was still increasing until the last day of the observation. Shannon-Wiener index (H’) calculation showed that diversity in primary and secondary forests were 3.48 and 3.50, respectively, thus classified as high (H’ &gt; 3). Sorensen index calculation (C<em><sub>N</sub></em>) showed high value reaching 0.5 quantitatively. The numbers of butterflies both species number and individual number, observed in the morning were higher than those in the afternoon. There was significant effect (P &lt; 0.05) of temperature on the number of individual butterflies. The result of PCA analysis showed that the environmental parameters in primary forest, secondary forest, gardens and settlements influenced the number of species and number of individuals.</p>

DLK1-DIO3 Region as a Source of Candidate Tumor Suppressor miRNAs in Papil- Lary Thyroid Carcinoma

2020 ◽  
Author(s):  
Leonardo Augusto Marson ◽  
Letícia Ferreira Alves ◽  
Micheli Severo Sielski ◽  
Cristina Pontes Vicente ◽  
Edna Teruko Kimura ◽  
...  
Keyword(s):  
Tumor Suppressor ◽  
Thyroid Carcinoma ◽  
Genomic Region ◽  
And Migration ◽  
The Individual ◽  
Computational Resources ◽  
The Impact ◽  
Tumor Suppressor Mirnas ◽  
Shed Light

Abstract Background: DLK1-DIO3 genomic region comprises one of the largest microRNA (miRNAs) clusters in human genome. In previous studies we showed the downregulation of several miRNAs from the genomic region in papillary thyroid carcinoma (PTC). Due to the large number of miRNAs within this region the individual contribution of these molecules to PTC development and progression remains unclear. Methods: We used different computational resources to clarify the contribution of DLK1-DIO3-derived miRNAs to PTC. Results: Our analysis suggests that 12 miRNAs from this region cooperate to modulate distinct cancer-relevant biological processes, potentially responding for most of the impact of DLK1-DIO3-derived miRNAs to PTC development and progression. The overexpression of miR-485-5p in two PTC cell lines decreased proliferation and migration, confirming the biological relevance of in silico data. Conclusion: Our results shed light on the role of DLK1-DIO3 region, harboring several tumor suppressor miRNAs in thyroid cancer and open perspectives for the functional exploration of these miRNAs as therapeutic targets for PTC.

Role of LncRNA CASC9 in oral carcinoma and its downstream gene expression and mechanism detected by nanomagnetic bead-based polymerase chain reaction

2021 ◽  
Vol 11 (7) ◽  
pp. 1017-1023
Author(s):  
Junjie Liu ◽  
Hong Mu ◽  
Xiangyong Cheng ◽  
Gangying Yuan ◽  
Qinqin Wang ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Oral Carcinoma ◽  
Luciferase Reporter ◽  
Chain Reaction ◽  
Total Rna ◽  
Polymerase Chain ◽  
And Migration ◽  
The Impact ◽  
Downstream Gene Expression

In view of the increasing incidence of oral carcinoma (OC), an in-depth understanding of the mechanism is required for future prevention and treatment. In modern medical research, the etiology of tumor diseases is mainly focused on gene changes, among which lncRNA is a trending topic. We speculated that lncRNA CASC9 may attribute to OC occurrence. To verify our conjecture, we extracted the total RNA of the research samples through nanomagnetic beads, detected the expression of CASC9 downstream genes miR-383-5p and KIF3B by polymerase chain reaction (PCR), and analyzed the impact of the three on OC cells and the targeting relationship. The total RNA extracted by nanomagnetic beads were found to be able to effectively improve the PCR speed, yield and the accuracy of the results, and reduce the allergic amplification results of the samples to be tested to obtain the best results. The detection result showed high CASC9 and KIF3B expression, and low miR-383-5p expression in OC cells. Inhibition of CASC9 and KIF3B and elevation of miR-383-5p can inhibit the viability of OC cells and boost apoptosis. Through dual-luciferase reporter (DLR) assay, the targeted regulation relationship between CASC9 and miR-383-5p and between miR-383-5p and KIF3B, was determined. Rescue experiments confirmed that CASC9 was able to modulate OC cell biological behaviors by targeting the miR-383-5p/KIF3B axis. Therefore, we argue that with high expression in OC, CASC9 can enhance the proliferation and migration of OC cells and inhibit the apoptosis through targeting the miR-383-5p/KIF3B axis.

Manifestation and symptomatology of depression in refugees and asylum seekers

2011 ◽  
Vol 26 (S2) ◽  
pp. 2138-2138
Author(s):  
M.C. Kastrup
Keyword(s):  
Host Country ◽  
Asylum Seekers ◽  
Depressive Illness ◽  
Cultural Aspects ◽  
Specific Factors ◽  
And Migration ◽  
Depressive Syndromes ◽  
Refugees And Asylum Seekers ◽  
The Impact

WHO has predicted that in 2020 depression will be the second most important cause of disability.Studies focusing on cross- cultural aspects of depression have increased during the last decade, and depression has been studied cross-culturally regarding their prevalence and symptomatology.The WHO study assessing depression across cultures reported a core symptomatology across the participating centres, but with certain differences in the ranking of problems in e.g. patients from non -industrialised nations somatic symptoms often dominate.Furthermore, there is increasing focus on the impact of migration on depressive illness. Depressive syndromes are clearly very common in migrants, and are probably the most frequent mental disorders in people who move to other countries. Refugees and asylum seekers are subjected to significant social and psychological stress and are more vulnerable. For scientific purposes it is vital though to differentiate between the different aspects of influence, for example the frequency of disorders and problems in treatment. Results of studies on increased psychological morbidity in migrants do not indicate whether increased vulnerability is associated with a migration background, or with acculturation problems in the host country due to cultural differences, or a combination of both factors. Both culture and migration-specific factors, as well as the level of integration into the host country, determine the conflicting arguments.The presentation will provide an overview of the burden of depression in relation to culture, differences in symptomatology, the role of migration and other circumstantial factors having an impact on the appearance and outcome of the disorder.

Methodological Challenges in the Study of Negotiator Affect

2004 ◽  
Vol 9 (3) ◽  
pp. 485-502 ◽  
Author(s):  
Ingrid Smithey Fulmer ◽  
Bruce Barry
Keyword(s):  
Empirical Research ◽  
Methodological Issues ◽  
Research Attention ◽  
The Real ◽  
Methodological Challenges ◽  
Affect States ◽  
The Impact

AbstractThis article examines methodological issues that accompany expanding research attention to affect and emotion in bargaining and negotiation. The role of affect in negotiation is presumed to have anterior, experiential, and strategic components. After reviewing existing empirical research on emotion as predictor, consequence, and tactic in negotiation, we consider complications that challenge the researcher's ability to isolate the impact of specific affect states on particular components of the negotiation dynamic. That analysis leads to a survey and discussion of potential methodological remedies that will increase the ability of researchers to capture the "real" emotions that individuals experience, express, mask, and strategically deploy within the negotiation encounter.

The impact of regional express trains from Moscow on population mobility

2020 ◽  
pp. 27-38
Author(s):  
A. A. Romashina
Keyword(s):  
Spatial Behavior ◽  
Population Mobility ◽  
System Transformation ◽  
Speed Increase ◽  
Settlement Structure ◽  
Migration Potential ◽  
And Migration ◽  
The Individual ◽  
The Impact

The paper is concerned with settlement system transformation in response to transport speed increase and changing the conditions of commuting. The article discusses the role of the individual spatial mobility as a part of settlement structure by the example of directions from Moscow to Tver’, Nizhny Novgorod, Orel, Belgorod, Kursk, where projects of significant railroad speed increase were operated in the 2010s. Transport accessibility improvement between Moscow and listed regional centers, caused by the launch of regional express trains, changed the spatial behavior of the inhabitants of these regions. The study of settlement structure transformation in response to transport connection speed increase was based on dynamics data of various types of trains passenger flows and the results of sociological surveys of regional express trains passengers. Conclusions are drawn about the role of commuting in the settlement structure and the factors of their transformation, depending on the speed characteristics, existing settlement structure and other geographical characteristics of the territory. The influence of these factors was different on the considered directions. Some of mentioned projects affected intra- (Tver’) and inter-agglomeration mobility (Nizhny Novgorod). Some cities (Oryol, Kursk, Belgorod) are characterized by small effects on commuting due to it’s sensitivity to the distance from Moscow and migration potential.

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