Hierarchical Clustering On Principal Components Research Articles

Fatty Acid Methyl Esters from the Herbal Industry Wastes as a Potential Feedstock for Biodiesel Production

Due to thegrowing awareness of fossil fuel depletion and environmental issues, biodiesel alternative fuel is currently of substantial interest. This research assessed herbal industry wastes as a potential resource for biodiesel production for the first time. Fatty acid methyl esters (FAMEs), obtained in the transesterification reaction, were extracted from the herbal samples by ultrasound-assisted extraction and identified withgas chromatography-mass spectrometry in the selected ion monitoring mode. The presence of at least 20 (e.g., in chamomile and chicory) FAMEs, up to 31 in nettle and senna, was reported. The unsaturated FAMEs were found in higher amounts than saturated. Linoleic acidwas the major polyunsaturated FAME in herbal wastes, while palmitic acid was the major saturated FAME. The highest content of FAMEs was identified in rye bran, Figure tea, and chicory. According to the cetane number prediction, BS EN 14214:2012+A2:2019, and hierarchical clustering on principal components (HCPC)wastes from, e.g., nettle, sage, and senna, are the most suitable in biodiesel production with fuel properties acceptable by the EuropeanStandards.Principal component analysis and HCPC allowed to classify and groupsimilar plants according to their FAMEs content; however, additional studies of herbal biofuel properties are needed.

P1432THE PRE-DIALYSIS CARE TRAJECTORIES OF ESRD PATIENTS: WHAT TYPES AND WHAT FACTORS OF EMERGENCY DIALYSIS START?

Abstract Background and Aims According to the REIN registry, in France in 2017, 30% of incident end-stage renal disease (ESRD) patients started dialysis in emergency. Emergency dialysis start (ES) is associated with higher risks of morbidity and mortality as well as a decreased quality of life for patients. The objectives were to describe groups of patients with similar care trajectories (or “types”) and identify the factors associated with ES. Method Data from the French REIN registry linked with the French national health insurance database (SNDS) were used. Patients aged 18 years old and older who started dialysis in 2015 in France were included. The 2 years pre-dialysis care trajectory was defined using 8 key components of ambulatory and hospital CKD care consumption. Multiple Correspondence Analysis (MCA) on these components was performed before a Hierarchical Clustering on Principal Components (HCPC) in order to identify types of care trajectories. Logistic regression models including both patients’ characteristics and the key CKD healthcare consumption were used to identify factors associated with ES. Results Among the 8856 patients included, 2681 (30.3%) started dialysis in emergency. The HCPC identified 6 types of pre-dialysis care trajectories. ES rate ranged from 11% to 62% depending on the type. Patient’s profiles were also different between types of trajectories, including age and comorbidities (diabetes prevalence ranged from 22% to 56%). For example, the 5th and 6th types of pre-dialysis care trajectories with high ES rates were characterized by low and absent CKD healthcare consumption respectively. They were shared by younger and less comorbid patients (26.7% and 25.7% aged < 45 years old, 66.5% and 59.4% without any cardiovascular diseases respectively). Conversely to the absence of nephrologist follow-up, the absence of general practitioner follow-up was not significantly associated with ES (OR=1.83, CI 95% [1.58-2.13] and OR=0.79, CI 95% [0.61-1.04] respectively). Conclusion Exploiting the strength of the combined use of clinical and healthcare consumption data, our study shows the diversity of pre-dialysis care trajectories of CKD patients. While some of these types of trajectories can be explained by patients’ clinical and demographic characteristics, complementary qualitative approaches are required to fully understand ES. Some types, as well as ES associated factors, highlight the need for earlier CKD screening and nephrologist referral.

Conversion to organic farming increases dairy farmers’ satisfaction independently of the strategies implemented

Farmers in Europe are increasingly converting to organic farming. For farmers, the conversion is an uncertain period that requires multiple changes to comply with organic regulations while not obtaining the organic price for products. Previous research findings highlight the multiple risks of converting to organic farming, but they tend to neglect farmers’ satisfaction during the conversion. Our objective was to investigate whether and how farmers could improve their satisfaction during the conversion to organic. We surveyed a sample of 19 dairy farms in Aveyron, France, from 2016 (their last year as conventional) to 2018. We (i) characterised the evolution of dairy farmers’ satisfaction and the conversion strategies implemented from the last year of conventional farming up to the end of the conversion to organic, and (ii) identified which conversion strategies improved farmers’ satisfaction the most. Satisfaction was assessed by farmers regarding economic, agronomic, livestock-related, and social aspects as well as work conditions. We ran principal component analysis (PCA), hierarchical clustering on principal components (HCPC), and partial least squares (PLS) regression to analyse the data. Our results revealed that all farmers were satisfied after conversion to organic. All observed conversion strategies were oriented towards pasture-based grazing systems and a reduction in land use and herd management intensities. It was not possible to relate specific conversion strategies to specific changes in patterns of satisfaction. This study was the first trying to relate the evolution of farmers’ satisfaction to changes in farming practices during the conversion to organic. In showing the strong increase in farmers’ satisfaction during the conversion to organic, our results strongly contrast with previous studies that highlighted the multiple risks of converting to organic farming. When supporting farmers considering a conversion, local advisers may consider farmers’ objectives and their potential satisfaction regarding their achievements beyond the risks of not obtaining the organic price for products immediately.

Exploring Developmental and Behavioral Heterogeneity among Preschoolers with ASD: A Cluster Analysis on Principal Components.

Children with autism spectrum disorder (ASD) present with heterogeneous levels of abilities and deficits. The identification of subgroups within a specific age range could be useful for understanding prognosis and treatment planning. We applied Hierarchical Clustering on Principal Components (HCPC) with a sample of 188 preschoolers with ASD and identified three distinct subgroups based on multiple developmental and behavioral domains. Cluster 1 was characterized by relatively high cognitive, language and adaptive abilities, and relatively low levels of social symptoms, repetitive behaviors, and sensory issues within the sample. Cluster 2 was characterized by similarly high cognitive, language and adaptive abilities compared to Cluster 1, but more severe social deficits as well as repetitive and sensory behaviors. Finally, Cluster 3 was characterized by lower cognitive, language and adaptive abilities, and more severe social, repetitive, and sensory symptoms. These findings provide insights into how considering multiple developmental and behavioral domains and core autism symptoms simultaneously can distinguish subgroups of young children with ASD and provide more comprehensive developmental profiles. Moreover, the unique profile of children in Cluster 2 highlighted the usefulness of including different measures and informants when evaluating the abilities and deficits of preschoolers with ASD and the importance of understanding the relationships among different developmental and behavioral factors in this specific population. Autism Res 2020, 13: 796-809. © 2020 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Children with autism exhibit a range of abilities and deficits in different developmental and behavioral areas, making it difficult to tailor treatment and predict outcomes. We identified three distinct subgroups among 188 preschoolers with autism spectrum disorder distinguished by the combination of measures from multiple developmental and behavioral domains. The findings revealed the importance of comprehensive profiling of the child's abilities and deficits to inform subgrouping within autism.

Characterization of the phenotypic diversity of tsiperifery (Piper spp.), the wild pepper from Madagascar under-studied in spite of its international fame

Tsiperifery is a wild pepper found in the rainforests of Madagascar. It has many uses that are well-known to the Malagasy and its demand on the international market is growing. It is a liana of the genus Piper (Piperaceae). Its taxonomic position is particularly uncertain. At present, it is unclear whether the natural populations should be grouped into one or more species and whether the species correspond to the taxa described. This study was carried out in order to resolve this vagueness about taxonomy. To characterize phenotypic variability, morphometric analyses were performed on 179 individuals using 29 descriptors of the leaf, inflorescence and fructification. The morphological classification was performed using factor analysis of mixed data (FAMD) and hierarchical clustering on principal components (HCPC). The results showed that tsiperifery comprises four distinct morphotypes that probably do not all correspond to the described species. The main distinguishing characteristics of these morphotypes are related to the leaves shape and thickness of the limb, and to the fruit size, shape of the stipe and berries. These results should be completed with a study of genetic variability to provide the scientific basis for a taxonomic revision of the Piper genus in Madagascar. This will provide a solid tool to guide foundations for the protection and management of this important heritage.

GIS-based approach to identify climatic zoning: A hierarchical clustering on principal component analysis

In tropical environments, the design of bioclimatic houses adapted to their environment represents a crucial issue when considering thermal comfort and limiting energy consumption. A preliminary aspect of such design endeavors is the acquisition of accurate knowledge regarding the climatic conditions in each region of the studied territory. The objective of this paper is to propose a climatic zoning for Madagascar from a database of 47 meteorological stations by performing hierarchical clustering on principal components (HCPC). The results are then combined with spatial interpolation using geographic information system (GIS) tools, enabling us to define three climate zones corresponding to dry, humid and highland areas. These results make it possible to define standard meteorological files to evaluate the thermal performance of traditional Malagasy houses. Regardless of the type of house and the areas considered, the percentage of thermal comfort according to the Givoni bioclimatic chart varies from average values of 20% without ventilation to 70% with an air velocity of 1 m/s. In summary, Madagascar's traditional habitat typologies have adapted over time to the constraints of their environment.

In vitro digestion and fermentation characteristics of tropical ingredients, co-products and by-products with potential use in diets for rabbits

The objective of this work was to evaluate and classify 16 tropical ingredients, co-products and by-products with potential use in rabbit feeding. We evaluated alfalfa hay, maize, wheat bran, soybean meal, crumbled maize with straw and cob (CMSC), soybean hull, citrus pulp, sugarcane bagasse, coffee husk, macauba seed cake meal (Acrocomia aculeata; MSCM), desmanthus hay (Desmanthus virgatus), sicklepod hay (Senna obtusifolia), neem hay (Azadirachta indica), Sodom apple hay (Calotropis procera), Barbados gooseberry hay (Pereskia aculeata) and moringa hay (Moringa oleifera). Chemically, were quantified dry matter (DM), crude protein (CP), ether extract (EE), neutral detergent fiber (aNDF), acid detergent fiber (ADF) and their nitrogen content (NDIN and ADIN, respectively), lignins, hemicelluloses, cellulose and non-fiber carbohydrates (NFC). Were evaluated the in vitro digestibility (ivDMdig) and degradability (ivDMdeg) of DM, and fermentation parameters, maximum amount of gas produced (B, mL/g DM), specific rate of gas production (C), decay of the specific rate of gas production (A), maximum fermentation rate (MFR, mL/h), time for maximum fermentation rate (TMFR, h) and latency time (LAG, h), using caecal inoculum for the in vitro evaluations. Were performed the hierarchical clustering on principal components (HCPC) of the data collected in the in vitro evaluations and obtained the matrix containing Pearson’s correlation coefficients between the chemical composition and the in vitro parameters. The values of DM, CP, Ash, EE, aNDF, ADF, lignins, hemicelluloses, cellulose, NDIN, ADIN, GE and NFC ranged from 857 to 906 g/kg, 22.9–552 g/kg DM, 7.0–153 g/kg, 5.26–136 g/kg DM, 204–697 g/kg DM, 20.6–493 g/kg DM, 2.27–226 g/kg DM, 73–443 g/kg DM, 18.3–437 g/kg DM, 25.3–395 g/kg CP, 19.9–227 g/kg CP, 13.3–21.7 MJ/kg and 38.9–690 g/kg, respectively. The results for ivDMdig, ivDMdeg, B, C, A, TMFR, MFR and LAG ranged from 0.21 to 0.84, 0.22 a 0.67, 79.9–348 mL/g DM, 2.75–4.44, 0.08 to 0.30, 8.58–38.8 h, 2.99–9.32 mL/h and 0.07–6.51 h, respectively. The results of the HCPC analysis determined the classification of the feeds into four groups: Group I contain sugarcane bagasse, coffee husk and citrus pulp; Group II contain soybean hull, desmanthus hay, MSCM, moringa hay and Barbados gooseberry hay; Group III contain alfalfa hay, Sodom apple hay, soybean meal, wheat bran, sicklepod hay and neem hay and Group IV contain maize and CMCS.

Analysis of scientific production on interorganizational networks study field

Analysis of scientific production on interorganizational networks study field

Rearing performances and environmental assessment of sea cage farming in Tunisia using life cycle assessment (LCA) combined with PCA and HCPC

The present study aims to understand the influence of rearing practices and the contributions of production phases of fish farming to their environmental impacts and determine which practices and technical characteristics can best improve the farms’ environmental performance. Another objective is to identify the influence of variability in farming practices on the environmental performances of sea cage aquaculture farms of sea bass and sea bream in Tunisia by using principal component analysis (PCA) and hierarchical clustering on principal components (HCPC) methods and then combining the classification with life cycle assessment (LCA). The approach consisted of three major steps: (i) of the 24 aquaculture farms in Tunisia, 18 were selected which follow intensive rearing practices in sea cages of European sea bass (Dicentrarchus labrax) and gilthead sea bream (Sparus aurata) and then a typology was developed to classify the studied farms into rearing practice groups using HCPC; (ii) LCA was performed on each aquaculture farm and (iii) mean impacts and contributions of production phases were calculated for each group of farms. Impact categories included acidification, eutrophication, global warming, land occupation, total cumulative energy demand and net primary production use. Results revealed high correlation between rearing practices and impacts. The feed-conversion ratio (FCR), water column depth under the cages and cage size had the greatest influence on impact intensity. Rearing practices and fish feed were the greatest contributors to the impacts studied due to the production of fish meal and oil and the low efficiency of feed use, which generated large amounts of nitrogen and phosphorus emissions. It is necessary to optimise the diet formulation and to follow better feeding strategies to lower the FCR and improve farm performance. Water column depth greatly influenced the farms’ environmental performance due to the increase in waste dispersion at deeper depths, while shallow depths resulted in accumulation of organic matter and degradation of water quality. Cage size influences environmental performances of aquaculture farms. Thus, from an environmental viewpoint, decision makers should grant licences for farms in deeper water with larger cages and encourage them to improve their FCRs. This study is the first attempt to combine the HCPC method and the LCA framework to study the environmental performance of aquacultural activity. The typology developed captures the variability among farms because it considers several farm characteristics in the classification. The LCA demonstrated that technical parameters in need of improvement are related to the technical expertise of farm managers and workers and to the location of the farm.

No risk, no fun: implications for positioning of online casinos

This study uses textual content analysis of online casinos to provide insights into how operators position themselves in the market. Qualitative data from the About Us pages of 19 online gambling websites is gathered and analysed using DICTION software. The resulting z-scores are further analysed using the Hierarchical Clustering on Principal Components (HCPC) function in the FactoMineR software package. Results indicate that the casinos investigated group into three distinct and meaningful clusters (activity/realism; low certainty; high certainty). The results confirm that this exploratory methodology, which combines computerized lexical analysis using DICTION and HCPC, is able to identify positioning differences. In addition, the presence of a relationship between identified clusters and casino rankings is also considered. Its confirmation suggests that casinos that emphasize risk (low certainty) are more likely to obtain higher rankings. The Web has provided a platform for a global online gambling industry where differentiation and positioning is crucial. Therefore, managers need to emphasize in their online and offline communication the often-held perception that one of the attractions of gambling is the thrill or excitement of beating the odds. Limitations are noted and possible areas for further research are indicated.

A new approach to the identification of regional clusters: hierarchical clustering on principal components

This study focuses on the identification of regional business clusters as a primary step in the design and implementation of cluster-based development strategies. A methodology that has not been used previously to identify clusters is applied to data on inter-industry linkages from the input–output table of a region in northern Spain. The first advantage of this approach, hierarchical clustering on principal components (HCPC), over the use of factorial analysis alone, is that it involves the application of objective clustering techniques to the principal components analysis results, which leads to a better cluster solution. A second advantage is derived from using a mixed algorithm for the clustering process – a combination of the Ward’s classification method with the K-means algorithm – which improves the robustness of the final results.

Generation Y, wine and alcohol. A semantic differential approach to consumption analysis in Tuscany

The aim of the study is the elicitation of the consumer’s semantic perception of different alcoholic beverages in order to provide information for the definition of communication strategies for both the private sector (and specifically the wine industry) and the public decision maker. Such information can be seen as the basis of a wider social marketing construct aimed at the promotion of responsible drinking among young consumers. The semantic differential approach was used in this study. The data collection was based on a survey to 430 consumers between 18 and 35years old in Tuscany, Italy. The database was organized in a three-way structure, indexing the data in a multiway matrix. The data were processed using a Multiple Factor Analysis (MFA). Moreover, homogeneous clusters of consumers were identified using a Hierarchical Clustering on Principal Components (HCPC) approach. The results of the study highlight that beer and spirits are mainly perceived as “Young”, “Social”, “Euphoric”, “Happy”, “Appealing” and “Trendy” beverages, while wine is associated mostly with terms such as “Pleasure”, “Quality” and “Comfortable”. Furthermore, the cluster analysis allowed for the identification of three groups of individuals with different approaches to alcohol drinking. The results of the study supply a useful information framework for the elaboration of specific communication strategies that, based on the drinking habits of young consumers and their perception of different beverages, can use a language that is very close to the consumer typologies. Such information can be helpful for both private and public communication strategies.

Chemodiversity of Ursane‐ and Oleanane‐Type Triterpenes in Amazonian Burseraceae Oleoresins

The oleoresins exuded from species of the Burseraceae family present high potential due to their biological and pharmacological properties. The evaluation of the chemodiversity of the oleoresins of 23 Amazonian species of Burseraceae provided a profile of the principal constituents, viz., the ursane-type triterpenes α-amyrin (1), α-amyrenone (3), and brein (5) and the oleanane-type triterpenes β-amyrin (2), β-amyrenone (4), and maniladiol (6), and allowed to determine which of these species have the highest biotechnological potential and which ones are rich in other, potentially new, triterpenes or volatile compounds of interest for the cosmetics industry. The oleoresin compositions obtained by GC-FID and GC/MS analyses were submitted to principal component analysis (PCA) and hierarchical clustering on principal components (HCPC), which divided the 23 samples in five clusters. Protium giganteum and Trattinnickia peruviana, constituting the first cluster, presented high oleoresin contents of 3 and 4 (28.8 and 16.3% on average, resp.). The seven species of Burseraceae composing the second cluster were potential producers of new triterpenes and volatile compounds. Dacryodes hopkinsii and five Protium species (third cluster) presented average contents for all the triterpenes analyzed. The highest contents of 5 and 6 (averages of 3.9 and 5.4%, resp.) were observed in P. heptaphyllum ssp. ullei and T. glaziovii (fourth cluster). Finally, the six Protium species forming the fifth cluster showed high contents of 1 and 2 (48.0 and 19.9% on average, resp.). Moreover, this study allowed the description of the triterpene composition of 13 not previously investigated species.