nested analysis
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Author(s):  
Alberto Doretto ◽  
Joseph P. Receveur ◽  
Edward A. Baker ◽  
M. Eric Benbow ◽  
Kim T. Scribner

2021 ◽  
Vol 9 ◽  
Author(s):  
Manuela Mancini ◽  
Åsmund Rinnan

Waste wood is becoming an appealing alternative material to virgin wood, and the main drivers are the increased demand for waste wood by the panel industry, the introduction of renewable energy policies, and the waste framework directive. In fact, the use of waste wood as a secondary resource is favored over both landfills and combustion. The best reuse and cascading use of the material are linked to its characteristics. That is why it is important to know the chemical composition and the variation in the properties of such a heterogeneous material. In this article, a sampling study was carried out in a panel board company located in the northern part of Italy. In order to investigate the heterogeneity of waste wood, all samples have been analyzed by near-infrared spectroscopy. Nested analysis of variance and principal component analysis have been used to evaluate the heterogeneity and the variation in sample properties. The approach gives information about how to ensure representative measurements and efficiently describe the variability of the material. The results suggest that it is important to have replicates or at least two subsamples for each lot and then measure each of these with at least 100 scans, in order to get representative measurements and describe the variability of the material. The determination of waste wood composition and variability is the focal point for improving the sorting process and increasing the reuse of waste wood, avoiding expensive landfills and risks for human health and the environment.


2021 ◽  
pp. 112067212110136
Author(s):  
Sumit Randhir Singh ◽  
Oliver Beale ◽  
Gideon Nkrumah ◽  
Mohammed Abdul Rasheed ◽  
Niroj Kumar Sahoo ◽  
...  

Purpose: To correlate sectoral choroidal vascularity with angiographic leakage in eyes with central serous chorioretinopathy (CSCR). Methods: This was a retrospective, cross-sectional study including patients with active CSCR. Multimodal imaging including fundus fluorescein angiography (FFA) and optical coherence tomography (OCT) were performed to identify leakage site and obtain choroidal measurements, respectively. An automated algorithm was used to perform shadow compensation, choroidal boundary localization and binarization, three (3-D) dimensional mapping, and early treatment of diabetic retinopathy study (ETDRS) grid based choroidal quantification that is, choroidal thickness (CT) and choroidal vascularity index (CVI). Nested analysis of variance (ANOVA) was performed to compare CT and CVI in different sectors. Results: Thirty-two eyes with active CSCR were analyzed. CT values varied significantly among the sectors (range, 450.27–482.63 µm; p = 0.005) and rings (range, 459.71–480.45 µm; p < 0.001), however, CVI failed to show significant variation among various segments (sectors, rings, and quadrants; range, 0.53–0.54; all p values > 0.05). Among 25 leaking spots in 25 different sectors, 12 (48%) had an increased CT compared to the overall CT whereas only 24% had increased CVI compared to overall CVI. Mean CT and CVI of the sectors with leakage (427.1 ± 81.1 µm; 0.51 ± 0.05) and remaining sectors without leakage (411.3 ± 73.9 µm; 0.53 ± 0.04) were not statistically different ( p = 0.48; p = 0.12, respectively). Conclusion: Though CT varied in different segments and increased CT corresponded to leakage points on FFA in 48% of eyes, CVI changes were more diffusely spread and local changes in CVI were not predictive of leakage location in eyes with active CSCR.


2021 ◽  
Vol 8 (1) ◽  
pp. e000824
Author(s):  
Vishnu Jeganathan ◽  
Linda Rautela ◽  
Simon Conti ◽  
Krisha Saravanan ◽  
Alyssa Rigoni ◽  
...  

BackgroundDespite increasing capacity to remotely monitor non-invasive ventilation (NIV), how remote data varies from day to day and person to person is poorly described.MethodsSingle-centre, 2-month, prospective study of clinically stable adults on long-term NIV which aimed to document NIV-device variability. Participants were switched to a ventilator with tele-monitoring capabilities. Ventilation settings and masking were not altered. Raw, extensible markup language data files were provided directly from Philips Respironics (EncoreAnywhere). A nested analysis of variance was conducted on each ventilator variable to apportion the relative variation between and within participants.ResultsTwenty-nine people were recruited (four withdrew, one had insufficient data for analyses; 1364 days of data). Mean age was 54.0 years (SD 18.4), 58.3% male with body mass index of 37.0 kg/m2 (13.7). Mean adherence was 8.53 (2.23) hours/day and all participants had adherence >4 hours/day. Variance in ventilator-derived indices was predominantly driven by differences between participants; usage (61% between vs 39% within), Apnoea–Hypopnoea Index (71% vs 29%), unintentional (64% vs 36%) and total leak (83% vs 17%), tidal volume (93% vs 7%), minute ventilation (92% vs 8%), respiratory rate (92% vs 8%) and percentage of triggered breaths (93% vs 7%).InterpretationIn this clinically stable cohort, all device-derived indices were more varied between users than the day-to-day variation within individuals. We speculate that normative ranges and thresholds for clinical intervention need to be individualised, and further research is necessary to determine the clinically important relationships between clinician targets for therapy and patient-reported outcomes.


2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Gad Murenzi ◽  
Patrick Tuyisenge ◽  
Faustin Kanyabwisha ◽  
Athanase Munyaneza ◽  
Benjamin Muhoza ◽  
...  

Abstract Background Persistent infection with high-risk human papillomavirus (hrHPV) is a critical step in cervical carcinogenesis. We report on type-specific hrHPV persistence, clearance and incidence among screen-positive Rwandan women living with HIV (WLWH). Methods This was a nested analysis from a large cervical cancer screening study of ~ 5000 Rwandan WLWH. Women who tested positive for hrHPV and/or visual inspection with acetic acid were referred to colposcopy. For a subset of women (n = 298) who were ≥ 6 months delayed in receiving colposcopy, we tested their screening and colposcopy visit specimens using the AmpFire HPV genotyping assay that tests 14 hrHPV types (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, and 68) individually. Results The mean, median (interquartile range [IQR]) and range of time between the screening and colposcopy visits were 644, 650 (490–820.5) and 197–1161 days, respectively. Mean, median (IQR) and range of age at the screening visit were 38, 37 (34–43) and 30–54 years, respectively. Two-hundred eighty-three (95.0%) had CD4 count (cells per mm3) data available at baseline with mean, median (IQR) and range of 592, 513 (346–717) and 0–7290, respectively. Two-hundred thirty-five WLWH were positive for at least one hrHPV type at the screening visit, of whom 50.2% had at least one HPV type-specific infection persist; 37.2% of all HPV infections detected at the screening visit persisted. Compared to all other HPV types in aggregate, HPV16 (vs. non-HPV16 types) (47.7%, p = 0.03) and HPV33 (vs. non-HPV33 types) (56.7%, p = 0.03) were significantly more likely, and HPV39 (vs. non-HPV39 types) (6.7%, p = 0.01), HPV51 (vs. non-HPV51 types) (15.6%, p < 0.01), and HPV66 (vs. non-HPV66 types (17.9%, p = 0.04) were significantly less likely, to persist. Lower CD4 counts were associated with having any persistent hrHPV infection (ptrend = 0.04) and multiple persistent hrHPV infections (ptrend = 0.04). Conclusion There is a significant proportion of WLWH with persistent hrHPV infection, emphasizing the need to vaccinate them against HPV prior to becoming sexually active.


2021 ◽  
Author(s):  
Valery Ridde ◽  
Lara Gautier ◽  
Christian Dagenais ◽  
Fanny Chabrol ◽  
Renyou Hou ◽  
...  

Abstract Background: All prevention efforts currently being implemented for COVID-19 are aimed at reducing the burden on strained health systems and human resources. There has been little research conducted to understand how SARS-CoV-2 has affected healthcare systems and professionals in terms of their work. Finding effective ways to share the knowledge and insight between countries, including lessons learned, is paramount to the international containment and management of the COVID-19 pandemic. The aim of this project is to compare the pandemic response to COVID-19 in Brazil, Canada, China, France, Japan, and Mali. This comparison will be used to identify strengths and weaknesses in the response, including challenges for health professionals and health systems.Methods: We will use a multiple case study approach with multiple levels of nested analysis. We chose these countries as they represent different continents and different stages of the pandemic. We will focus on several major hospitals and two public health interventions (contact tracing and testing). It is a multidisciplinary research approach that will use qualitative data through observations, document analysis, and interviews, as well as quantitative data based on disease surveillance data and other publicly available data. Given that the methodological approaches of the project are largely qualitative, the ethical risks are minimal. For the quantitative component, the data being used are publicly available.Discussion: We will deliver lessons learned based on a rigorous process and on strong evidence to enable operational-level insight for national and international stakeholders.


Foods ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 976
Author(s):  
Cho-Long Lee ◽  
Soo-Hyun Lee ◽  
Ga-Gyeong Seo ◽  
Jae-Hee Hong

Familiarity and ethnic authenticity have a significant influence on the liking of ethnic food. Thus, it is crucial to identify the degree to which a dish can be modified in order to increase hedonic responses and familiarity without the loss of ethnic authenticity. This study determined the degree to which perceptions of the Korean rice dish, bibimbap, would vary upon modification of its ingredients, cooking process, or plating using the Southeast Asian market as a model system. The dish was prepared in Korean style or as Nasi Goreng, the Southeast Asian style. Eight formulations (2 ingredients × 2 cooking methods × 2 plating styles) were tested by panels, including 77 Southeast Asians and 72 Koreans. Hedonic responses, familiarity, ethnic authenticity, and purchase intent were evaluated using a nested analysis of variance. Ingredients and cooking methods had a significant influence on liking and perceived ethnic authenticity. In addition, plating had a substantial effect on the perception of ethnic authenticity and expected liking. Overall, the rate of positive responses increased when region-specific cooking processes and plating were matched. Taken together, our results suggest that modification of familiar dishes needs to be carefully considered as it can have complex effects on liking and perceived ethnic authenticity.


PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7097
Author(s):  
Carmen Gloria Fuentealba Jara ◽  
Reinaldo Rivera ◽  
Cristian Franco ◽  
Ricardo Figueroa ◽  
Victor Faúndez

The freshwater mussels from Chile are characterized by a high percentage of endemism and a fragmented latitudinal diversity, which has been attributed to the features and geomorphological history sculpted by the hydrographic basins. In this work, a set of hypothesis under a macroecological approach is addressed, with the aim to explore environmental, topographic and hydrological factors that define the latitudinal distribution of this mussel group. In order to achieve this goal, Rapoport’s rule, geometrics limits and co-ocurrence were evaluated. In addition, we analyze the source and sink hypotheses through the nested analysis. We observed a noticeable mid-domain effect (MDE), where a major richness than expected was randomly observed between 40 and 41°S. The results revealed that the distribution pattern was not concordant with Rapoport’s rule (r = 0.123; p = 0.128). Regarding to historical dynamic of the distribution, the results show a significant nestedness pattern, suggesting a source-sink dynamic, that is, poorer communities are a subset of richer communities in species. According to the co-occurrence analysis, an aggregate pattern existed, suggesting potential regulatory mechanisms. The specific richness pattern is explained by the variable seasonality of the temperature with a variance percentage explained of 35%. The full model indicated that variables which characterize the heterogeneity of habitat (i.e. range, Shannon), water availability (i.e., precipitation, density of water bodies) and topography (i.e., altitude area available) jointly explain 40% of the variability of the observed richness. This study shows that the geographical distribution of mollusc richness is mainly explained by mainly climatic and topographical environmental components, as well as by the source-sink dynamics.


Author(s):  
Erica Jarosch ◽  
Qian Wang ◽  
Lucas Schmotzer ◽  
Yongwook Kim

This paper presents an adaptive radial basis functions (RBFs) metamodeling method for design optimization of structures. Various numerical techniques have been developed and adopted in structural and multidisciplinary optimization. To evaluate responses of a structural or mechanical engineering system, finite element (FE) analyses are routinely used. An FE code shall be integrated with an optimization algorithm in a nested analysis and design of structures. Therefore, software input/output programming is required. A metamodeling method, on the contrary, expresses structural responses using an approximate function, so that the FE software is not directly coupled in the numerical optimization loop. Any optimization algorithm can be applied to find the optimal design, based on the explicit response functions. In this study, numerical examples were created and FE analyses were first performed at sample points. Subsequently, metamodels were constructed and a gradient-based optimization algorithm was applied. At the optimal point of one adaptive iteration, accuracy of the RBF metamodel was checked, and additional sample points were added to the sample pool to improve the model accuracy. The adaptive iterations continued, until the convergence of the objective function was achieved. The proposed optimization method worked well for a numerical example, and the optimal result was found within a few adaptive iterations.


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