King Juan Carlos University
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Coincidence theorems for finite topological spaces
No full textIn this work, we adapt the definition of the Vietoris map to the setting of finite topological spaces and establish several coincidence theorems.From these theorems, we derive a Lefschetz fixed point theorem for multivalued maps, which extends recent results in the field.Finally, we illustrate an application of this theory in approximating discrete dynamical systems
Effects of Personality Types on the Performance of Educational Teams
No full textThe objective of this study is to explore how various personality types correlate with enhanced work performance. The Enneagram type of the participants in the experiment was established by using the simplest version of the Riso-Hudson test. A two-way ANOVA was performed under the principles of the Design of Experiments, which allowed the identification of main effects and interactions in the response, i.e., the marks of the university teams. We found that the interactions between certain Enneagram types seem to increase the average performance marks as a primary effect. Conversely, when certain Enneagram types coincided within a team, the marks significantly decreased, posing a risk to project success. According to our results, the Enneagram framework may be used as a preliminary stage for identifying potential team members for future projects
Comprehensive Study on Endocrine Disruptor Removal from Wastewater Using Different Microalgae Species
No full textThe concentration of endocrine disruptor compounds (EDCs) in wastewater is increasing, posing significant risks to living organisms. This study concerns the simultaneous degradation of a variety of EDCs from wastewater, including methylparaben (MeP), propylparaben (PrP), butylparaben (BuP), benzophenone (BP), bisphenol A (BPA), and estrone (E), in the presence of the microalgae Scenedesmus sp. or Chlorella vulgaris. The potential for the abiotic removal of these EDCs and their underlying degradation mechanisms were also studied. The presence of microalgae significantly enhanced the degradation of parabens, achieving complete removal within 7 days, primarily through the mechanism of biodegradation. BPA removal was also improved by microalgae, reaching 82% and 90% within 7 days with Scenedesmus sp. and C. vulgaris, respectively. BP degradation was predominantly abiotic, accomplishing 95% removal in 7 days. E degradation was mainly abiotic, achieving approximately 40% within 7 days, with a notable contribution from a biodegradation mechanism in the later stages, accounting for 27% and 40% of the final total removal in the presence of Scenedesmus sp. and C. vulgaris, respectively. This study provides insights into the mechanisms of EDC degradation by microalgae, highlighting the potential of Scenedesmus sp. and C. vulgaris to remove a mixture of EDCs from wastewater.This research was funded by the Ministry of Science and Innovation and co-financed by the European Social and Regional Development Funds (PID2020-114943RB-I00), the Community
of Madrid, and the European Structural Funds (IND2020/AMB-17480) and RENUWAL network (320RT0005), financed by the CYTED Program
Two atypical new species of the genus Sectonema Thorne, 1930 (Nematoda, Dorylaimida, Aporcelaimidae) from Vietnam
No full textTwo new species of the genus Sectonema from natural habitats of northern Vietnam are studied. This paper includes their descriptions, measurements, line illustrations, and light microscope (LM) and scanning electron microscope (SEM) pictures. Sectonema tropicum sp. nov. is characterized by a 2.56-3.24 mm long body, 19-21 mu m broad lip region, odontostyle 20-21 mu m long at its ventral side, 730-834 mu m long neck, pharyngeal expansion occupying 52-59% of total neck length, uterus a simple tube-like structure 150-242 mu m long or 1.2-2.5 times the body diameter, pars refringens vaginae present, V = 48-52, short (31-40 mu m, c = 70-91, c = 0.5-0.6) and rounded tail, 91-97 mu m long spicules, and only one weakly developed ventromedian supplement. Sectonema vietnamense sp. nov. is characterized by its slender (a = 33-49) and 2.71-4.25 mm long body, 14-16 mu m broad lip region, odontostyle 8-9 mu m long at its ventral side, 716-918 mu m long neck, pharyngeal expansion occupying 63-67% of total neck length, uterus simple and 209-242 mu m long or 2.5-2.9 times the corresponding body diameter, pars refringens vaginae absent, V = 54, short (34-39 mu m, c = 70-115, c = 0.6-0.8) and rounded tail, 59-75 mu m long spicules, and three or four irregularly spaced ventromedian supplements bearing hiatus. Both species are also characterized by their nearly continuous lip region, an atypical feature in this genus. Molecular analysis of S. tropicum sp. nov. confirms that Sectonema is a natural (monophyletic) taxon, very close to Metaporcelaimus
Morphological and molecular characterisation of new and known species of Tripyla Bastian, 1865 (Triplonchida: Tripylidae) from northern Iran, with phylogenetic relationships, compendium and identification key
No full textDuring a nematological survey of the family Tripylidae, two new and two known species of the genus Tripyla, namely T. paraffinis sp. n., T. parafilicaudata sp. n., T. glomerans and T. setifera, were identified and described from soil samples collected from the rhizosphere of forest trees in northern Iran. Three populations of T. paraffinis sp. n., found in different locations, are described and morphometric data of the type and other populations provided. Tripyla paraffinis sp. n. is characterised by its body length of 1.21-1.89 mm, dorsal tooth wedge-shaped and triangular, short outer labial and cephalic sensilla, tail bent ventrad and gradually tapering to the end, horn-shaped spicules bearing a distinct constriction in the middle, and presence of 16-20 ventromedian supplementary papillae. Tripyla parafilicaudata sp. n. is described and illustrated from four different locations. It is characterised by females with a body length of 1.48-1.95 mm, dorsal tooth hook-shaped, vaginal wall with a downward pointing tooth-like projection in the middle, long outer labial and setiform cephalic sensilla, long tail, sausage-shaped spermatozoa, males with horn-shaped spicules and 11-17 ventromedian supplementary papillae. Tripyla glomerans and T. setifera are new records for the Iranian nematofauna. The results of phylogenetic analyses based on sequences of the partial 18S and D2-D3 expansion segments of 28S rRNA from T. paraffinis sp. n. and T. parafilicaudata sp. n. and other species in the genus clearly support the proposal of T. paraffinis sp. n. and T. parafilicaudata sp. n. as new species, as well as indicating that Tripyla shares a more recent common ancestor with Tobrilus, Tripylella, Prismatolaimus, Diphtherophora and two trichodorids, Trichodorus and Paratrichodorus. The Tripylidae is placed in a main clade within the Triplonchida
Identifying high-risk pregnancies in rural areas with machine-manifold learning
No full textMaternal mortality remains unacceptably high, particularly in developing countries, where 99% of cases occur, most of which are preventable. In Guatemala, disparities in maternal healthcare quality between urban and rural areas exacerbate this issue. The Healthy Pregnancy project, initiated by the EHAS Foundation, sought to address this gap by equipping rural nurses with prenatal care kits, enabling them to perform screenings comparable to those in urban settings. This study presents a retrospective secondary analysis of data collected during the project (2014–2016), encompassing 10,108 cases and 108 features. Using Data Science and machine learning (ML) methodologies, we compared Support Vector Machines (SVM) and Random Forest (RF) algorithms to classify pregnancies requiring referral to higher-level care, where the referral decision was defined based on the retrospective assessment of obstetric specialists using clinical, laboratory, and ultrasound data. Their performance was evaluated against the benchmark sensitivity (0.62) and specificity (0.98) of trained nurses. SHAP (Shapley Additive exPlanations) values were employed to interpret model predictions and identify the most critical features influencing classification. Furthermore, manifold learning techniques, specifically Uniform Manifold Approximation and Projection (UMAP), were utilized to uncover latent structures within the data, offering additional interpretability via SHAP analysis. Our results show that both models (RF and SVM) achieve sensitivity and specificity values comparable to those obtained by trained nurses when techniques such as SMOTE (Synthetic Minority Oversampling Technique) and cost-sensitive learning are applied to address the imbalanced dataset. UMAP and SHAP analyses revealed the most globally relevant features. These findings demonstrate the potential of ML-driven approaches to support clinical decision-making in resource-limited settings, enhancing the detection of high-risk pregnancies, reducing training demands, and facilitating the monitoring of prenatal checkups in such contexts
Assessing Performance in Shoulder Arthroscopy: The Imperial Global Arthroscopy Rating Scale (IGARS)
No full textBackground: Surgical training is undergoing major changes with reduced resident work hours and an increasing focus on patient safety and surgical aptitude. The aim of this study was to create a valid, reliable method for an assessment of arthroscopic skills that is independent of time and place and is designed for both real and simulated settings. The validity of the scale was tested using a virtual reality shoulder arthroscopy simulator. Methods: The study consisted of two parts. In the first part, an Imperial Global Arthroscopy Rating Scale for assessing technical performance was developed using a Delphi method. Application of this scale required installing a dual-camera system to synchronously record the simulator screen and body movements of trainees to allow an assessment that is independent of time and place. The scale includes aspects such as efficient portal positioning, angles of instrument insertion, proficiency in handling the arthroscope and adequately manipulating the camera, and triangulation skills. In the second part of the study, a validation study was conducted. Two experienced arthroscopic surgeons, blinded to the identities and experience of the participants, each assessed forty-nine subjects performing three different tests using the Imperial Global Arthroscopy Rating Scale. Results were analyzed using two-way analysis of variance with measures of absolute agreement. The intraclass correlation coefficient was calculated for each test to assess inter-rater reliability. Results: The scale demonstrated high internal consistency (Cronbach alpha, 0.918). The intraclass correlation coefficient demonstrated high agreement between the assessors: 0.91 (p < 0.001). Construct validity was evaluated using Kruskal-Wallis one-way analysis of variance (chi-square test, 29.826; p < 0.001), demonstrating that the Imperial Global Arthroscopy Rating Scale distinguishes significantly between subjects with different levels of experience utilizing a virtual reality simulator. Conclusions: The Imperial Global Arthroscopy Rating Scale has a high internal consistency and excellent inter-rater reliability and offers an approach for assessing technical performance in basic arthroscopy on a virtual reality simulator
Development and Validation of the Pregnancy Guilt Assessment Scale (PGAS): A Specific Tool for Assessing Guilt in Pregnancy
No full textBackground: Gestational guilt is an understudied emotional experience that can affect maternal well-being and prenatal bonding. This study aimed to develop and validate the Pregnancy Guilt Assessment Scale (PGAS) in a sample of Spanish pregnant women, assessing its factorial structure, reliability, and validity. Methods: Four phases were conducted: (1) item generation through focus groups (n = 17) and cognitive interviews (n = 8); (2) expert content validation (n = 3); (3) exploratory factor analysis (EFA) in a pilot sample (n = 85); and (4) confirmatory factor analysis (CFA) and validity testing in an independent sample (n = 171). Additional measures included antenatal depression, prenatal distress, affect, self-esteem, social support, and dispositional guilt. Internal consistency, correlations, and multiple regressions assessed reliability and convergent and incremental validity. Results: The final 16-item PGAS showed a bifactor structure with a general factor and four dimensions: G-LSC (Lack of self-care), G-UEE (Unmet emotional expectations), G-SP (Social pressure), and G-CWR (Conflict with work role). The model demonstrated good fit (χ2 = 109.42, df = 88, p = 0.061; CFI = 0.974; TLI = 0.965; RMSEA = 0.069; SRMR = 0.030) and high reliability (α total = 0.96; ω = 0.98; subscales α = 0.90–0.94). PGAS scores correlated positively with dispositional guilt, negative affect, prenatal distress, and antenatal depression. In regressions, G-UEE uniquely predicted depression (β = 0.213, p = 0.002) and G-SP predicted distress (β = 0.303, p < 0.001). Women who had considered pregnancy termination scored higher on guilt (p < 0.001). Conclusions: The PGAS is a reliable and valid instrument for assessing pregnancy-related guilt in Spanish women, with potential relevance for perinatal mental health research and clinical practice, while future studies should evaluate its performance in other cultural settings
Description of two new species of the genus Hemicycliophora (Nematoda: Hemicycliophoridae) from the USA
No full textTwo species of sheath nematodes were studied using an integrative approach, combining morphological and molecular analyses. The first species was collected from an oak tree (Quercus sp.) imported from Texas into Florida, while the second one was obtained from the ornamental palm Phoenix sylvestris in a Florida nursery. These species were compared to a closely related species, Hemicaloosia uarki, which was originally described in Arkansas. Phylogenetic analyses using partial 18S rRNA, D2-D3 expansion segments of 28S rRNA, ITS rRNA, and COI gene sequences revealed that sheath nematodes from Texas and Florida represent two new species of the genus Hemicycliophora, which are described here as Hemicycliophora ornata sp. n. and H. silvestris sp. n., respectively. In the phylogenetic tree based on ITS rRNA gene sequences, Hemicaloosia uarki grouped within a clade of other Hemicycliophora species rather than within the Hemicaloosia species clade, indicating that this species belongs to the genus Hemicycliophora rather than to Hemicaloosia. Consequently, this species was reclassified as Hemicycliophora uarki comb. n. These findings confirmed that morphological characters traditionally used to distinguish Hemicaloosia species from those of Hemicycliophora are valid but insufficient for reliable identification when some life stages, such as males, are absent. The presence of males with straight spicules is a very useful character to validate the morphological identification of Hemicaloosia species. In absence of this life stage, phylogenetic analysis of gene sequences is the only reliable method to accurately differentiate sheath nematodes resembling Hemicaloosia from Hemicycliophora. - 18S rRNA D2-D3 of 28S rRNA ITS rRN
Description of Paravulvus zhongshanensis sp
No full textParavulvus zhongshanensis sp. nov., isolated from soil in a location at Jiangsu Province, China, is described and illustrated based on morphological, morphometric and molecular characterizations. The new species is characterized by its body 1.17-1.53 mm long, lip region offset by marked constriction and 12.1-13.8 μm broad, mural tooth deltoid and 9.6-11.7 μm long, neck 278-360 μm long, pharyngeal expansion 164-208 μm long or occupying more than one-half (54-62%) of total neck length, uterus 32.5-35.3 μm long or 1.0-1.1 times the corresponding body diameter, V = 47.8-53.4, paravulvae absent, female tail subcylindrical conoid (30.5-39.5 μm, c = 36.0-45.5, c' = 1.7-2.2) with widely rounded end, and male unknown. The new species was compared with six known species of the genus including Paravulvus acuticaudatus, Paravulvus confusus, Paravulvus hartingii, Paravulvus iranicus, Paravulvus loofi and Paravulvus microdontus mainly by similarities in having conical tail and c' value larger than 1.3. The rRNA and mitochondrial cytochrome oxidase subunit 1 genes of the new species were obtained and were used for reconstructing the phylogenetic relationships of the new species