scholarly journals Beyond species: why ecological interaction networks vary through space and time

2014 ◽  
Author(s):  
Timothée Poisot ◽  
Daniel B Stouffer ◽  
Dominique Gravel
Keyword(s):  
Species Interactions ◽  
Scale Up ◽  
Predictive Ability ◽  
Population Based ◽  
Species Interaction ◽  
Interaction Networks ◽  
Future Research ◽  
Intrinsic Variability ◽  
New Approach ◽  
Emerging Ecosystems

Community ecology is tasked with the considerable challenge of predicting the structure, and properties, of emerging ecosystems. It requires the ability to understand how and why species interact, as this will allow the development of mechanism-based predictive models, and as such to better characterize how ecological mechanisms act locally on the existence of inter-specific interactions. Here we argue that the current conceptualization of species interaction networks is ill-suited for this task. Instead, we propose that future research must start to account for the intrinsic variability of species interactions, then scale up from here onto complex networks. This can be accomplished simply by recognizing that there exists intra-specific variability, in traits or properties related to the establishment of species interactions. By shifting the scale towards population-based processes, we show that this new approach will improve our predictive ability and mechanistic understanding of how species interact over large spatial or temporal scales.

scholarly journals Vulnerable species interactions are important for the stability of mutualistic networks

2019 ◽  
Author(s):  
Benno I. Simmons ◽  
Hannah S. Wauchope ◽  
Tatsuya Amano ◽  
Lynn V. Dicks ◽  
William J. Sutherland ◽  
...  
Keyword(s):  
Species Interactions ◽  
Species Coexistence ◽  
Species Interaction ◽  
Interaction Networks ◽  
Ecological Communities ◽  
Ecological Context ◽  
Intrinsic Properties ◽  
Network Stability ◽  
Starting Point ◽  
The Stability

AbstractSpecies are central to ecology and conservation. However, it is the interactions between species that generate the functions on which ecosystems and humans depend. Despite the importance of interactions, we lack an understanding of the risk that their loss poses to ecological communities. Here, we quantify risk as a function of the vulnerability (likelihood of loss) and importance (contribution to network stability in terms of species coexistence) of 4330 mutualistic interactions from 41 empirical pollination and seed dispersal networks across six continents. Remarkably, we find that more vulnerable interactions are also more important: the interactions that contribute most to network stability are those that are most likely to be lost. Furthermore, most interactions tend to have more similar vulnerability and importance across networks than expected by chance, suggesting that vulnerability and importance may be intrinsic properties of interactions, rather than only a function of ecological context. These results provide a starting point for prioritising interactions for conservation in species interaction networks and, in areas lacking network data, could allow interaction properties to be inferred from taxonomy alone.

Solid Lipid Nanoparticles: A Promising Drug Delivery Technology

2009 ◽  
Vol 2 (2) ◽  
pp. 509-516
Author(s):  
S. Pragati ◽  
S. Kuldeep ◽  
S. Ashok ◽  
M. Satheesh
Keyword(s):  
Drug Delivery ◽  
Solid Lipid Nanoparticles ◽  
Large Scale ◽  
Colloidal Particles ◽  
Scale Up ◽  
Lipid Nanoparticles ◽  
Scale Production ◽  
Research Activity ◽  
New Approach ◽  
Solid Lipid

One of the situations in the treatment of disease is the delivery of efficacious medication of appropriate concentration to the site of action in a controlled and continual manner. Nanoparticle represents an important particulate carrier system, developed accordingly. Nanoparticles are solid colloidal particles ranging in size from 1 to 1000 nm and composed of macromolecular material. Nanoparticles could be polymeric or lipidic (SLNs). Industry estimates suggest that approximately 40% of lipophilic drug candidates fail due to solubility and formulation stability issues, prompting significant research activity in advanced lipophile delivery technologies. Solid lipid nanoparticle technology represents a promising new approach to lipophile drug delivery. Solid lipid nanoparticles (SLNs) are important advancement in this area. The bioacceptable and biodegradable nature of SLNs makes them less toxic as compared to polymeric nanoparticles. Supplemented with small size which prolongs the circulation time in blood, feasible scale up for large scale production and absence of burst effect makes them interesting candidates for study. In this present review this new approach is discussed in terms of their preparation, advantages, characterization and special features.

scholarly journals A microRNA panel compared to environmental and polygenic scores for colorectal cancer risk prediction

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Janhavi R. Raut ◽  
Ben Schöttker ◽  
Bernd Holleczek ◽  
Feng Guo ◽  
Megha Bhardwaj ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Risk Prediction ◽  
Risk Score ◽  
Characteristic Curve ◽  
Predictive Ability ◽  
Population Based ◽  
Polygenic Risk Score ◽  
Nucleotide Polymorphisms ◽  
Polygenic Scores

AbstractCirculating microRNAs (miRNAs) could improve colorectal cancer (CRC) risk prediction. Here, we derive a blood-based miRNA panel and evaluate its ability to predict CRC occurrence in a population-based cohort of adults aged 50–75 years. Forty-one miRNAs are preselected from independent studies and measured by quantitative-real-time-polymerase-chain-reaction in serum collected at baseline of 198 participants who develop CRC during 14 years of follow-up and 178 randomly selected controls. A 7-miRNA score is derived by logistic regression. Its predictive ability, quantified by the optimism-corrected area-under-the-receiver-operating-characteristic-curve (AUC) using .632+ bootstrap is 0.794. Predictive ability is compared to that of an environmental risk score (ERS) based on known risk factors and a polygenic risk score (PRS) based on 140 previously identified single-nucleotide-polymorphisms. In participants with all scores available, optimism-corrected-AUC is 0.802 for the 7-miRNA score, while AUC (95% CI) is 0.557 (0.498–0.616) for the ERS and 0.622 (0.564–0.681) for the PRS.

scholarly journals Flexible Modeling of Net Survival and Cure by AML Subtype and Age: A French Population-Based Study from FRANCIM

2021 ◽  
Vol 10 (8) ◽  
pp. 1657
Author(s):  
Morgane Mounier ◽  
Gaëlle Romain ◽  
Mary Callanan ◽  
Akoua Alla ◽  
Olayidé Boussari ◽  
...  
Keyword(s):  
Population Based ◽  
Future Research ◽  
French Population ◽  
Monocytic Leukemia ◽  
Younger Patients ◽  
Younger Women ◽  
Net Survival ◽  
Flexible Modeling ◽  
Acute Myelomonocytic Leukemia ◽  
Sex Disparity

With improvements in acute myeloid leukemia (AML) diagnosis and treatment, more patients are surviving for longer periods. A French population of 9453 AML patients aged ≥15 years diagnosed from 1995 to 2015 was studied to quantify the proportion cured (P), time to cure (TTC) and median survival of patients who are not cured (MedS). Net survival (NS) was estimated using a flexible model adjusted for age and sex in sixteen AML subtypes. When cure assumption was acceptable, the flexible cure model was used to estimate P, TTC and MedS for the uncured patients. The 5-year NS varied from 68% to 9% in men and from 77% to 11% in women in acute promyelocytic leukemia (AML-APL) and in therapy-related AML (t-AML), respectively. Major age-differenced survival was observed for patients with a diagnosis of AML with recurrent cytogenetic abnormalities. A poorer survival in younger patients was found in t-AML and AML with minimal differentiation. An atypical survival profile was found for acute myelomonocytic leukemia and AML without maturation in both sexes and for AML not otherwise specified (only for men) according to age, with a better prognosis for middle-aged compared to younger patients. Sex disparity regarding survival was observed in younger patients with t-AML diagnosed at 25 years of age (+28% at 5 years in men compared to women) and in AML with minimal differentiation (+23% at 5 years in women compared to men). All AML subtypes included an age group for which the assumption of cure was acceptable, although P varied from 90% in younger women with AML-APL to 3% in older men with acute monoblastic and monocytic leukemia. Increased P was associated with shorter TTC. A sizeable proportion of AML patients do not achieve cure, and MedS for these did not exceed 23 months. We identify AML subsets where cure assumption is negative, thus pointing to priority areas for future research efforts.

scholarly journals The association between varying levels of palliative care involvement on costs during terminal hospitalizations in Canada from 2012 to 2015

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Sarina R. Isenberg ◽  
Christopher Meaney ◽  
Peter May ◽  
Peter Tanuseputro ◽  
Kieran Quinn ◽  
...  
Keyword(s):  
Palliative Care ◽  
Metastatic Cancer ◽  
Estimating Equation ◽  
Population Based ◽  
Future Research ◽  
Chronic Obstructive ◽  
Discharge Abstract Database ◽  
High Involvement ◽  
Hospitalization Costs ◽  
The Cost

Abstract Background Inpatient palliative care is associated with lower inpatient costs; however, this has yet to be studied using a more nuanced, multi-tiered measure of inpatient palliative care and a national population-representative dataset. Using a population-based cohort of Canadians who died in hospital, our objectives were to: describe patients’ receipt of palliative care and active interventions in their terminal hospitalization; and examine the relationship between inpatient palliative care and hospitalization costs. Methods Retrospective cohort study using data from the Discharge Abstract Database in Canada between fiscal years 2012 and 2015. The cohort were Canadian adults (age ≥ 18 years) who died in hospital between April 1st, 2012 and March 31st, 2015 (N = 250,640). The exposure was level of palliative care involvement defined as: medium-high, low, or no palliative care. The main measure was acute care costs calculated using resource intensity weights multiplied by the cost of standard hospital stay, represented in 2014 Canadian dollars (CAD). Descriptive statistics were represented as median (IQR), and n(%). We modelled cost as a function of palliative care using a gamma generalized estimating equation (GEE) model, accounting for clustering by hospital. Results There were 250,640 adults who died in hospital. Mean age was 76 (SD 14), 47% were female. The most common comorbidities were: metastatic cancer (21%), heart failure (21%), and chronic obstructive pulmonary disease (16%). Of the decedents, 95,450 (38%) had no palliative care involvement, 98,849 (38%) received low involvement, and 60,341 (24%) received medium to high involvement. Controlling for age, sex, province and predicted hospital mortality risk at admission, the cost per day of a terminal hospitalization was: $1359 (95% CI 1323: 1397) (no involvement), $1175 (95% CI 1146: 1206) (low involvement), and $744 (95% CI 728: 760) (medium-high involvement). Conclusions Increased involvement of palliative care was associated with lower costs. Future research should explore whether this relationship holds for non-terminal hospitalizations, and whether palliative care in other settings impacts inpatient costs.

scholarly journals Outdoor Air Pollution and Depression in Canada: A Population-Based Cross-Sectional Study from 2011 to 2016

2021 ◽  
Vol 18 (5) ◽  
pp. 2450
Author(s):  
Ashley K. Dores ◽  
Gordon H. Fick ◽  
Frank P. MacMaster ◽  
Jeanne V. A. Williams ◽  
Andrew G. M. Bulloch ◽  
...  
Keyword(s):  
Air Pollution ◽  
Fine Particulate Matter ◽  
Canadian Community Health Survey ◽  
Population Based ◽  
Cross Sectional Study ◽  
Future Research ◽  
Outdoor Air ◽  
Cross Sectional ◽  
Outdoor Air Pollution ◽  
Environmental Health Research

To assess whether exposure to increased levels of outdoor air pollution is associated with psychological depression, six annual iterations of the Canadian Community Health Survey (n ≈ 127,050) were used to estimate the prevalence of a major depressive episode (2011–2014) or severity of depressive symptoms (2015–2016). Survey data were linked with outdoor air pollution data obtained from the Canadian Urban Environmental Health Research Consortium, with outdoor air pollution represented by fine particulate matter ≤2.5 micrometers (μm) in diameter (PM2.5), ozone (O3), sulfur dioxide (SO2), and nitrogen dioxide (NO2). Log-binomial models were used to estimate the association between outdoor air pollution and depression, and included adjustment for age, sex, marital status, income, education, employment status, urban versus rural households, cigarette smoking, and chronic illness. No evidence of associations for either depression outcomes were found. Given the generally low levels of outdoor air pollution in Canada, these findings should be generalized with caution. It is possible that a meaningful association with major depression may be observed in regions of the world where the levels of outdoor air pollution are greater, or during high pollution events over brief time intervals. Future research is needed to replicate these findings and to further investigate these associations in other regions and populations.

scholarly journals The concept of neutrality: a new approach

2019 ◽  
Vol 76 (1) ◽  
pp. 333-353 ◽  
Author(s):  
Stephen Macdonald ◽  
Briony Birdi
Keyword(s):  
Literature Review ◽  
Design Methodology ◽  
Information Science ◽  
Social Institutions ◽  
Future Research ◽  
Library And Information Science ◽  
New Approach ◽  
Content Type ◽  
Normative Framework ◽  
Contextual Awareness

Purpose Neutrality is a much debated value in library and information science (LIS). The “neutrality debate” is characterised by opinionated discussions in contrasting contexts. The purpose of this paper is to fill a gap in the literature by bringing these conceptions together holistically, with potential to deepen understanding of LIS neutrality. Design/methodology/approach First, a literature review identified conceptions of neutrality reported in the LIS literature. Second, seven phenomenographic interviews with LIS professionals were conducted across three professional sectors. To maximise variation, each sector comprised at least one interview with a professional of five or fewer years’ experience and one with ten or more years’ experience. Third, conceptions from the literature and interviews were compared for similarities and disparities. Findings In four conceptions, each were found in the literature and interviews. In the literature, these were labelled: “favourable”, “tacit value”, “social institutions” and “value-laden profession”, whilst in interviews they were labelled: “core value”, “subservient”, “ambivalent”, and “hidden values”. The study’s main finding notes the “ambivalent” conception in interviews is not captured by a largely polarised literature, which oversimplifies neutrality’s complexity. To accommodate this complexity, it is suggested that future research should look to reconcile perceptions from either side of the “neutral non-neutral divide” through an inclusive normative framework. Originality/value This study’s value lies in its descriptive methodology, which brings LIS neutrality together in a holistic framework. This framework brings a contextual awareness to LIS neutrality lacking in previous research. This awareness has the potential to change the tone of the LIS neutrality debate.

Cox Survival Analysis of Microarray Gene Expression Data Using Correlation Principal Component Regression

2007 ◽  
Vol 6 (1) ◽  
Author(s):  
Qiang Zhao ◽  
Jianguo Sun
Keyword(s):  
Gene Expression ◽  
Gene Expression Data ◽  
Principal Component Regression ◽  
Predictive Ability ◽  
Principal Component ◽  
Microarray Gene Expression Data ◽  
Expression Data ◽  
Microarray Gene Expression ◽  
New Approach ◽  
Microarray Gene

Statistical analysis of microarray gene expression data has recently attracted a great deal of attention. One problem of interest is to relate genes to survival outcomes of patients with the purpose of building regression models for the prediction of future patients' survival based on their gene expression data. For this, several authors have discussed the use of the proportional hazards or Cox model after reducing the dimension of the gene expression data. This paper presents a new approach to conduct the Cox survival analysis of microarray gene expression data with the focus on models' predictive ability. The method modifies the correlation principal component regression (Sun, 1995) to handle the censoring problem of survival data. The results based on simulated data and a set of publicly available data on diffuse large B-cell lymphoma show that the proposed method works well in terms of models' robustness and predictive ability in comparison with some existing partial least squares approaches. Also, the new approach is simpler and easy to implement.

Dynamic capabilities vs. innovation capability: are they related?

2014 ◽  
Vol 21 (3) ◽  
pp. 368-384 ◽  
Author(s):  
Lidija Breznik ◽  
Robert D. Hisrich
Keyword(s):  
Literature Review ◽  
Design Methodology ◽  
Dynamic Capabilities ◽  
Dynamic Capability ◽  
Future Research ◽  
Innovation Capability ◽  
New Approach ◽  
Content Type ◽  
New Research ◽  
The Relationship

Purpose – The purpose of this paper is to provide insights into the relationship between dynamic capabilities and innovation capabilities. It links dynamic capability with innovation capability and indicates the ways they can be related. Design/methodology/approach – The relationships between dynamic and innovation capability were investigated through a systematic literature review. Findings – The review indicates that common characteristics exist between of the both fields, which demonstrate six relationships. Additionally, findings show some inconsistencies and even contradictions. Originality/value – In this paper, the authors have compared dynamic capabilities, a relatively new approach in the field of strategic management, with innovation capabilities, a widely recognised crucial domain for sustained competitiveness. Since both areas address issues that are essential to today's environment, future research should seek to clarify both concepts, by undertaking some new research and developing comprehensive and unambiguous framework.

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