The Abundant Niche-centroid Hypothesis: Key Points About Unfilled Niches and the Potential Use of Supraspecfic Modeling Units

2020 ◽  
Vol 15 (3) ◽  
pp. 92-102
Author(s):  
Carlos Yañez ◽  
Gerardo Martín ◽  
Luis Osorio-Olvera ◽  
Jazmín Escobar-Luján ◽  
Sandra Castaño-Quintero ◽  
...  

Correlative estimates of fundamental niches are gaining momentum as an alternative to predict species’ abundances, particularly via the abundant niche-centroid hypothesis (an expected inverse relationship between species’ abundance variation across its range and the distance to the geometric centroid of its multidimensional ecological niche). The main goal of this review is to recapitulate what has been done, where we are now, and where should we move towards in regards to this hypothesis. Despite evidence in support of the abundance-distance to niche centroid relationship, its usefulness has been highly debated, although with little consideration of the underlying theory regarding the circumstances that might break down the relationship. We address some key points about the conditions needed to test the hypothesis in correlative studies, specifically in relation to nichecharacterization and configurations of the Biotic-Abiotic-Mobility (BAM) framework to illustrate the problem of unfilled niches. Using a created supraspecific modeling unit, we show that species for which only a portion of their fundamental niche is represented in their area of historical accessibility (M)—i.e., when the environmental equilibrium condition is violated—it is impossible to characterize their true niche centroid. Therefore, we strongly recommend to analyze this assumption prior toassess the abundant niche-centroid hypothesis. Finally, we discuss the potential of using modeling units above the species level for cases in which environmental conditions associated with species’ occurrences may not be sufficient to fully characterize their fundamental niches.

Zoosymposia ◽  
2014 ◽  
Vol 9 (1) ◽  
pp. 77-94 ◽  
Author(s):  
MARIA BATURINA ◽  
TARMO TIMM ◽  
OLGA LOSKUTOVA

The oligochaete fauna of 25 lakes located in the Polar and Subpolar regions of the Ural Mountains in Russia was studied. In total, 46 oligochaete taxa were collected, 32 of them identified to species level. Naididae had the highest number of taxa (19); the other taxa belonged to Pristinidae (2), Enchytraeidae (6), Tubificidae (10), Lumbriculidae (8) and Lumbricidae (1). Canonical correspondence analysis (CCA) was used to characterize the relationship between abundance of oligochaete species, abundance and biomass of all oligochaetes, abundance of separate families and environmental factors. Latitude, elevation, silt, detritus, moss and algal periphyton and depth were found to be factors influencing the distribution of oligochaetes.


2011 ◽  
Vol 8 (1) ◽  
pp. 131-134 ◽  
Author(s):  
Thomas D. Olszewski

Accumulations of dead skeletal material are a valuable archive of past ecological conditions. However, such assemblages are not equivalent to living communities because they mix the remains of multiple generations and are altered by post-mortem processes. The abundance of a species in a death assemblage can be quantitatively modelled by successively integrating the product of an influx time series and a post-mortem loss function (a decay function with a constant half-life). In such a model, temporal mixing increases expected absolute dead abundance relative to average influx as a linear function of half-life and increases variation in absolute dead abundance values as a square-root function of half-life. Because typical abundance distributions of ecological communities are logarithmically distributed, species' differences in preservational half-life would have to be very large to substantially alter species' abundance ranks (i.e. make rare species common or vice-versa). In addition, expected dead abundances increase at a faster rate than their range of variation with increased time averaging, predicting greater consistency in the relative abundance structure of death assemblages than their parent living community.


Author(s):  
Michael O’Toole

In this article I examine aspects of the relationship between mothers and sons from an attachment perspective in an Irish context. Through the works of Irish writers such as Seamus Heaney, John McGahern, and Colm Tóibín, I focus on particular aspects of this relationship, which fails to support the developmental processes of separation and individuation in the many men who come to me for psychotherapy. I illustrate key points concerning this attachment dynamic through the use of clinical examples of my work with two men from my practice. While acknowledging that many other cultural factors play a significant role in the emotional development of children, integrating the work of our poets, novelists, and scholars with an attachment perspective


2020 ◽  
Author(s):  
Hee Yun Lee ◽  
Yan Luo ◽  
Cho Rong Won ◽  
Jiyoung Lee ◽  
Jeongwon Baik

BACKGROUND The use of social media or social networking sites (SNS) is increasing across all age groups, and one of the primary motives of using SNS is to seek health-related information. Although previous research examining the effect of SNS use on depression exist, studies regarding the effect of SNS use for health purpose on depression is limited. OBJECTIVE Our study aims to explore the relationship between SNS use for health purpose and depression across the four age groups (18-34 years old, 35-49 years old, 50-64 years old, and above 65 years old). METHODS A sample of 6,789 adults aged 18 and older was extracted from a 2017 and 2018 Health Information National Trends Survey (HINTS). Univariate and bivariate analyses to examine the association between each variable and four age groups were conducted. Multiple linear regression analyses to predict depression level among participants with use of SNS for health purpose were conducted. RESULTS SNS use for health purpose and depression were positively associated for three age groups but not for those 65 years or older (=0.13, P<0.05; =0.08, P<0.05; =0.09, P<0.05). Income and self-reported health status indicated an inverse relationship for all age groups. The relationship with marital status differed based on age group with 18 and 34 years old showing an inverse relationship (=-0.13, P<0.01) while 65 years or older showing a positive relationship (=0.06, P<0.05). Gender was positively associated among those in the 35-49 years old (=0.09, P<0.05) and 65 years or older (=0.07, P<0.05). Being Non-Hispanic White was positively associated with depression among 50-64 years old (=0.07, P<0.001) and 65 years or older (=0.08, P<0.05). CONCLUSIONS Age-tailored education on determining accurate and reliable information shared via SNS is needed to reduce depressive symptoms.


Author(s):  
A. A. Sheptulin ◽  
O. A. Storonova

Aim of review. Interpretation of published evidence on the relationship between the excessive belching syndrome and functional dyspepsia (FD) and their management in patient care.Key points. According to the Rome IV criteria of functional gastrointestinal disorders (FGID), excessive belching in the absence of other dyspeptic symptoms is to be considered a manifestation of the excessive belching syndrome, which can be of gastric or supragastric nature. Combination of high-resolution manometry and impedancemetry allows an accurate diagnosis of belching and selection of optimal treatment strategy. Belching complicated by other symptoms of dyspepsia is to be considered yet another FD symptom according to the Rome IV criteria of FGID. Prokinetics are recommended to relieve belching in such cases.Conclusion. Understanding the relationship between the excessive belching syndrome and FD requires further research.


Author(s):  
Mark David Walker ◽  
Mihály Sulyok

Abstract Background Restrictions on social interaction and movement were implemented by the German government in March 2020 to reduce the transmission of coronavirus disease 2019 (COVID-19). Apple's “Mobility Trends” (AMT) data details levels of community mobility; it is a novel resource of potential use to epidemiologists. Objective The aim of the study is to use AMT data to examine the relationship between mobility and COVID-19 case occurrence for Germany. Is a change in mobility apparent following COVID-19 and the implementation of social restrictions? Is there a relationship between mobility and COVID-19 occurrence in Germany? Methods AMT data illustrates mobility levels throughout the epidemic, allowing the relationship between mobility and disease to be examined. Generalized additive models (GAMs) were established for Germany, with mobility categories, and date, as explanatory variables, and case numbers as response. Results Clear reductions in mobility occurred following the implementation of movement restrictions. There was a negative correlation between mobility and confirmed case numbers. GAM using all three categories of mobility data accounted for case occurrence as well and was favorable (AIC or Akaike Information Criterion: 2504) to models using categories separately (AIC with “driving,” 2511. “transit,” 2513. “walking,” 2508). Conclusion These results suggest an association between mobility and case occurrence. Further examination of the relationship between movement restrictions and COVID-19 transmission may be pertinent. The study shows how new sources of online data can be used to investigate problems in epidemiology.


2021 ◽  
Vol 147 (4) ◽  
pp. 1007-1017
Author(s):  
Branka Powter ◽  
Sarah A. Jeffreys ◽  
Heena Sareen ◽  
Adam Cooper ◽  
Daniel Brungs ◽  
...  

AbstractThe TERT promoter (pTERT) mutations, C228T and C250T, play a significant role in malignant transformation by telomerase activation, oncogenesis and immortalisation of cells. C228T and C250T are emerging as important biomarkers in many cancers including glioblastoma multiforme (GBM), where the prevalence of these mutations is as high as 80%. Additionally, the rs2853669 single nucleotide polymorphism (SNP) may cooperate with these pTERT mutations in modulating progression and overall survival in GBM. Using liquid biopsies, pTERT mutations, C228T and C250T, and other clinically relevant biomarkers can be easily detected with high precision and sensitivity, facilitating longitudinal analysis throughout therapy and aid in cancer patient management.In this review, we explore the potential for pTERT mutation analysis, via liquid biopsy, for its potential use in personalised cancer therapy. We evaluate the relationship between pTERT mutations and other biomarkers as well as their potential clinical utility in early detection, prognostication, monitoring of cancer progress, with the main focus being on brain cancer.


Insects ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 266
Author(s):  
Enrique Baquero ◽  
Rafael Jordana ◽  
Vicente M. Ortuño

Megalothorax minimus (Neelidae) and Sphaeridia pumilis (Sminthurididae) had already been identified in surface sampling from Sierra de Guadarrama. In Europe, Sminthurinus gisini (Katiannidae) seems to be associated with environments at specific altitudes, and has little representation in this sampling. Pygmarrhopalites custodum Baquero and Jordana sp. nov. (Arrhopalitidae) coexists with two previously identified surface occurring species of the same family (P. elegans and Arrhopalites caecus). However, P. custodum is more abundant, indicating that it occupies an ecological niche tending to troglophile in the mesovoid shallow substratum (MSS). Moreover, it is also more abundant in the MSS of higher altitude corresponding to the bioclimatic zones cryo-oro-Mediterranean and oro-Mediterranean supra forest. Allacma cryptica Baquero and Jordana sp. nov. (Sminthuridae), is another species that had not been previously detected on the surface in the study area. A. cryptica is an addition to a genus which has eight described species. Gisinurus malatestai (Sminthuridae) appears well represented in the MSS, being a species present very occasionally in the Mediterranean area. Two species of the genera Sminthurides (Sminthurididae) and Fasciosminthurus (Bourletiellidae) have been found, but they could not have been identified to the species level. Finally, a few specimens of Dicyrtomina minuta (Dicyrtomidae), an abundant species on the surface, have been captured.


Nutrients ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 972
Author(s):  
Susana Santiago ◽  
Itziar Zazpe ◽  
Cesar I. Fernandez-Lazaro ◽  
Víctor de la de la O ◽  
Maira Bes-Rastrollo ◽  
...  

No previous study has assessed the relationship between overall macronutrient quality and all-cause mortality. We aimed to prospectively examine the association between a multidimensional macronutrient quality index (MQI) and all-cause mortality in the SUN (Seguimiento Universidad de Navarra) (University of Navarra Follow-Up) study, a Mediterranean cohort of middle-aged adults. Dietary intake information was obtained from a validated 136-item semi-quantitative food-frequency questionnaire. We calculated the MQI (categorized in quartiles) based on three quality indexes: the carbohydrate quality index (CQI), the fat quality index (FQI), and the healthy plate protein source quality index (HPPQI). Among 19,083 participants (mean age 38.4, 59.9% female), 440 deaths from all causes were observed during a median follow-up of 12.2 years (IQR, 8.3–14.9). No significant association was found between the MQI and mortality risk with multivariable-adjusted hazard ratio (HR) for the highest vs. the lowest quartile of 0.79 (95% CI, 0.59–1.06; Ptrend = 0.199). The CQI was the only component of the MQI associated with mortality showing a significant inverse relationship, with HR between extreme quartiles of 0.64 (95% CI, 0.45–0.90; Ptrend = 0.021). In this Mediterranean cohort, a new and multidimensional MQI defined a priori was not associated with all-cause mortality. Among its three sub-indexes, only the CQI showed a significant inverse relationship with the risk of all-cause mortality.


1992 ◽  
Vol 71 (11) ◽  
pp. 1816-1821 ◽  
Author(s):  
C.A. Bibb ◽  
A.G. Pullinger ◽  
F. Baldioceda

Undifferentiated mesenchymal (UM) cells, the progenitor cells of the cartilage layer, have been assigned a significant role in TMJ articular tissue maintenance. This was based on reports of UM cell reduction with increased soft-tissue thickness for the condyle and temporal component. However, the strength of this inverse relationship was not presented and remained unclear. The purpose of the present study was to assess the strength of the correlation between UM cell presence and soft-tissue thickness in young adult TMJs at autopsy. Sagittal histological sections from the central thirds of 50 joints were evaluated with respect to articular soft-tissue thickness, histological character, and UM cell presence in the condyle and temporal component. The superior sector ofthe condyle and the articular eminence showed the greatest variability in soft-tissue thickness and were the only areas to show localized UM cell absence. The eminence was the only location to show an inverse relationship between soft-tissue thickness and UM cell presence, and this was consistent in both an ANOVA (p = 0.0016) and a Spearman correlation analysis. However, the strength of this correlation was only moderate (rho = -0.52), and no such relationship was observed in any other location. This study suggests that the relationship between UM cell presence and soft-tissue thickness is more complex than previously hypothesized and that the contribution of UM cells to articular tissue maintenance has been overstated, while other biological processes were overlooked.


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