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Model Sets with Euclidean internal Space
(Cambridge University Press, 0022-11-07) Allendes Cerda, Mauricio; Coronel, Daniel
We give a characterization of inter-model sets with Euclidean internal space. This characterization is similar to previous results for general inter-model sets obtained independently by Baake, Lenz and Moody, and Aujogue. The new ingredients are two additional conditions. The first condition is on the rank of the abelian group generated by the set of internal differences. The second condition is on a flow on a torus defined via the address map introduced by Lagarias. This flow plays the role of the maximal equicontinuous factor in the previous characterizations. © The Author(s), 2023. Published by Cambridge University Press.
Association between Fractional Oxygen Extraction from Resting Quadriceps Muscle and Body Composition in Healthy Men
(Multidisciplinary Digital Publishing Institute (MDPI), 0023) Yáñez-Sepúlveda, Rodrigo; Olivares-Arancibia, Jorge; Cortés-Roco, Guillermo; Vasquez-Bonilla, Aldo; Monsalves-Álvarez, Matías; Alvear-Órdenes, Ildefonso; Tuesta, Marcelo
This study aimed to associate body composition with fractional oxygen extraction at rest in healthy adult men. Fourteen healthy adults (26.93 ± 2.49 years) from Chile participated. Body composition was assessed with octopole bioimpedance, and resting muscle oxygenation was evaluated in the vastus lateralis quadriceps with near-infrared spectroscopy (NIRS) during a vascular occlusion test, analyzing the muscleVO2, resaturation velocity during reactive hyperemia via the muscle saturation index (%TSI), and the area above the curve of HHb (AACrep). It was observed that the total and segmented fat mass are associated with lower reoxygenation velocities during hyperemia (p = 0.008; β = 0.678: p = 0.002; β = 0.751), and that the total and segmented skeletal muscle mass are associated with higher reoxygenation velocities during hyperemia (p = 0.020; β = −0.614: p = 0.027; β = −0.587). It was also observed that the total and segmented fat mass were associated with a higher area above the curve of HHb (AACrep) during hyperemia (p = 0.007; β = 0.692: p = 0.037; β = 0.564), and that total and segmented skeletal muscle mass was associated with a lower area above the curve of HHb (AACrep) during hyperemia (p = 0.007; β = −0.703: p = 0.017; β = −0.632). We concluded that fat mass is associated with lower resaturation rates and lower resting fractional O2 extraction levels. In contrast, skeletal muscle mass is associated with higher resaturation rates and fractional O2 extraction during reactive hyperemia. The AACrep may be relevant in the evaluation of vascular adaptations to exercise and metabolic health. © 2023 by the authors.
Fermion mass hierarchy in an extended left-right symmetric model
(Springer Science and Business Media Deutschland GmbH, 0023) Bonilla, Cesar; Cárcamo Hernández A.E; Kovalenko, Sergey; Lee H.; Pasechnik R; Schmidt, Ivan
We present a Left-Right symmetric model that provides an explanation for the mass hierarchy of the charged fermions within the framework of the Standard Model. This explanation is achieved through the utilization of both tree-level and radiative seesaw mechanisms. In this model, the tiny masses of the light active neutrinos are generated via a three-loop radiative inverse seesaw mechanism, with Dirac and Majorana submatrices arising at one-loop level. To the best of our knowledge, this is the first example of the inverse seesaw mechanism being implemented with both submatrices generated at one- loop level. The model contains a global U(1) X symmetry which, after its spontaneous breaking, allows for the stabilization of the Dark Matter (DM) candidates. We show that the electroweak precision observables, the electron and muon anomalous magnetic moments as well as the Charged Lepton Flavor Violating decays, μ → eγ, are consistent with the current experimental limits. In addition, we analyze the implications of the model for the 95 GeV diphoton excess recently reported by the CMS collaboration and demonstrate that such anomaly could be easily accommodated. Finally, we discuss qualitative aspects of DM in the considered model. © 2023, The Author(s).
The effect of obesity on chronic diseases in USA: a flexible copula approach
(Nature Research, 0023) Dettoni, Robinson; Bahamondes, Clif; Yevenes, Carlos; Cespedes, Cristian; Espinosa, Javier
We analyze the effect of obesity on the incidence of hypertension, hyperlipidemia and diabetes in USA using a health production theoretical framework along with a bivariate flexible semi-parametric recursive copula model that account for endogeneity. In this approach, the effects of control variables are flexibly determined using additive predictors that allow for a variety of effects. Our findings suggest that there exist a positive and significant effect of obesity on the prevalence of all chronic diseases examined. In particular, after endogeneity is accounted for, the probability of having hypertension, hyperlipidemia and diabetes for obese individuals are, respectively, 35%, 28% and 11% higher than those under the obesity threshold. These findings suggest that lowering obesity rates could lead to significant reductions in the morbidity and mortality associated with these diseases. © 2023, The Author(s).
Statistical Analysis to Quantify the Impact of Map Type on Estimating Peak Discharge in Non-Instrumented Basins
(Universidad Tecnologica de Bolivar, 0023-08-11) Sierra-Sánchez, Alexandra; Gatica, Gustavo; Paternina-Verona, Duban A; Ramos, Helena M.
The calculation of peak discharge in non-instrumented basins requires including morphometric parameters, which in turn depend on the map type used. This study analyses the impact of and variation in peak discharges of the Caño Ricaurte basin, Colombia, based on three types of maps at different resolution scales. The reference map used was the map made for the detailed designs of the channel analysed, which was extracted from the Master Plan of the City. Additionally, maps from a 90 × 90 m digital elevation model and contour lines extracted from Google Earth were used. The time of concentration was determined by different equations (Kirpich, Témez, Bureau, and TR-55) using the mapping methods described above, and the peak discharge was determined using rainfall-runoff models. © 2023 by the authors.
Acceptability of HPV Vaccines: A Qualitative Systematic Review and Meta-Summary
(Multidisciplinary Digital Publishing Institute (MDPI), 0023-09) Urrutia, María-Teresa; Araya, Alejandra-Ximena; Gajardo, Macarena; Chepo, Macarena; Torres, Romina; Schilling, Andrea
In 2006, the human papillomavirus (HPV) vaccine was approved for use as an effective intervention for reducing the risk of developing cervical cancer; however, its successful implementation is dependent on acceptability. This study aims to provide a comprehensive understanding of the reasons that favor or do not favor the acceptability of HPV vaccines. Methods: We conducted a systematic review and meta-summary of qualitative research on 16 databases. A total of 32 articles that considered the perspectives of vaccine users, their parents, and the professionals who care for them were reviewed. Synthesis was conducted as described by Sandelowski and Barroso. Results: We used inductive and deductive methods to obtain a total of 22 dimensions, out of which three issues stood out that should be considered to improve acceptability and are formed by three groups of study, namely, information about the vaccine, fears and side effects, and sexuality associated with the vaccine. Conclusions: Acceptability, as well as adherence to HPV vaccination, is a complex concept. This review highlights the perspectives of the three sets of actors involved in the process (i.e., users, parents, and professionals) and views these factors in relation to acceptability as a guide for new interventions. © 2023 by the authors.
Detection of antimicrobial-resistant Enterobacterales in insectivorous bats from Chile
(Royal Society Publishing, 0023-11) Rojas-Sereno, Zulma Esperanza; Streicker, Daniel G; Suarez-Yana, Tania; Lineros, Michelle; Yung, Verónica; Godreuil, Sylvain; Benavides, Julio A
Enterobacterales of clinical importance for humans and domestic animals are now commonly detected among wildlife worldwide. However, few studies have investigated their prevalence among bats, particularly in bat species living near humans. In this study, we assessed the occurrence of Extended-spectrum beta-lactamase-producing (ESBL) and carbapenemase-resistant (CR) Enterobacterales in rectal swabs of bats submitted to the Chilean national rabies surveillance program from 2021 to 2022. From the 307 swabs screened, 47 (15%) harboured cefotaxime-resistant Enterobacterales. Bats carrying these bacteria originated from 9 out of the 14 Chilean regions. Most positive samples were obtained from Tadarida brasiliensis (n = 42), but also Lasiurus varius, L. cinereus and Histiotus macrotus. No Enterobacterales were resistant to imipenem. All ESBL-Enterobacterales were confirmed as Rahnella aquatilis by MALDI-TOF. No other ESBL or CR Enterobacterales were detected. To our knowledge, this is the first screening of antibiotic-resistant bacteria in wild bats of Chile, showing the bat faecal carriage of R. aquatilis naturally resistant to cephalosporins, but also including acquired resistance to important antibiotics for public health such as amoxicillin with clavulanic acid. Our results suggest unknown selective pressures on R. aquatilis, but low or no carriage of ESBL or CR Escherichia coli and Klebsiella spp. Future studies should assess the zoonotic and environmental implications of R. aquatilis, which are likely present in the guano left by bats roosting in human infrastructures. © 2023 The Authors.
The problem of the epistemological status of "Criminal labour law"
(Centro Estudios Derecho Penal, 0023-12) Morales, Juan Pablo Castillo
Differently from other countries, Chile lacks any kind of concept of what could be called, with a greater or lesser level of systematisation, “Criminal Labour Law”. Such a situation is particularly striking if one considers some valuable attempts at scientific theorisation and its progressive enshrinement in comparative law. However, in order to be clear about the reasons for this context, it is primary to clarify the elementary question of what is meant when we refer to Criminal Labour Law. Such is, precisely, the purpose of this brief paper: to approach an answer to the question of the meaning and scope of the expression Criminal Labour Law as a discipline, as well as an analysis of its location and status in terms of legal epistemology © 2023 Centro Estudios Derecho Penal. All rights reserved.
Implementation of web-based respondent driven sampling in epidemiological studies
(BioMed Central Ltd, 0023-12) Ferrer-Rosende, Pedro; Feijoo-Cid, María; Fernández-Cano, María Isabel; Salas-Nicás, Sergio; Stuardo-Ávila, Valeria; Navarro-Giné, Albert
Background: Respondent-driven sampling (RDS) is a peer chain-recruitment method for populations without a sampling frame or that are hard-to-reach. Although RDS is usually done face-to-face, the online version (WebRDS) has drawn a lot of attention as it has many potential benefits, despite this, to date there is no clear framework for its implementation. This article aims to provide guidance for researchers who want to recruit through a WebRDS. Methods: Description of the development phase: guidance is provided addressing aspects related to the formative research, the design of the questionnaire, the implementation of the coupon system using a free software and the diffusion plan, using as an example a web-based cross-sectional study conducted in Spain between April and June 2022 describing the working conditions and health status of homecare workers for dependent people. Results: The application of the survey: we discuss about the monitoring strategies throughout the recruitment process and potential problems along with proposed solutions. Conclusions: Under certain conditions, it is possible to obtain a sample with recruitment performance similar to that of other RDS without the need for monetary incentives and using a free access software, considerably reducing costs and allowing its use to be extended to other research groups. © 2023, BioMed Central Ltd., part of Springer Nature.
NEDD4-1 deficiency impairs satellite cell function during skeletal muscle regeneration
(BioMed Central Ltd, 0023-12) Cabezas, Felipe; Cabello-Verrugio, Claudio; González, Natalia; Salas, Jeremy; Ramírez, Manuel J.; de la Vega, Eduardo; Olguín, Hugo C
Background: Satellite cells are tissue-specific stem cells primarily responsible for the regenerative capacity of skeletal muscle. Satellite cell function and maintenance are regulated by extrinsic and intrinsic mechanisms, including the ubiquitin–proteasome system, which is key for maintaining protein homeostasis. In this context, it has been shown that ubiquitin-ligase NEDD4-1 targets the transcription factor PAX7 for proteasome-dependent degradation, promoting muscle differentiation in vitro. Nonetheless, whether NEDD4-1 is required for satellite cell function in regenerating muscle remains to be determined. Results: Using conditional gene ablation, we show that NEDD4-1 loss, specifically in the satellite cell population, impairs muscle regeneration resulting in a significant reduction of whole-muscle size. At the cellular level, NEDD4-1-null muscle progenitors exhibit a significant decrease in the ability to proliferate and differentiate, contributing to the formation of myofibers with reduced diameter. Conclusions: These results indicate that NEDD4-1 expression is critical for proper muscle regeneration in vivo and suggest that it may control satellite cell function at multiple levels. © 2023, The Author(s).
Removal of a partial genomic duplication restores synaptic transmission and behavior in the MyosinVA mutant mouse Flaile
(BioMed Central Ltd, 0023-12) Bustos, Fernando J.; Pandian, Swarna; Haensgen, Henny; Zhao, Jian-Ping; Strouf, Haley; Heidenreich, Matthias; Swiech, Lukasz; Deverman, Benjamin E.; Gradinaru, Viviana; Zhang, Feng; Constantine-Paton, Martha
Background: Copy number variations, and particularly duplications of genomic regions, have been strongly associated with various neurodegenerative conditions including autism spectrum disorder (ASD). These genetic variations have been found to have a significant impact on brain development and function, which can lead to the emergence of neurological and behavioral symptoms. Developing strategies to target these genomic duplications has been challenging, as the presence of endogenous copies of the duplicate genes often complicates the editing strategies. Results: Using the ASD and anxiety mouse model Flailer, which contains a partial genomic duplication working as a dominant negative for MyoVa, we demonstrate the use of DN-CRISPRs to remove a 700 bp genomic region in vitro and in vivo. Importantly, DN-CRISPRs have not been used to remove genomic regions using sgRNA with an offset greater than 300 bp. We found that editing the flailer gene in primary cortical neurons reverts synaptic transport and transmission defects. Moreover, long-term depression (LTD), disrupted in Flailer animals, is recovered after gene editing. Delivery of DN-CRISPRs in vivo shows that local delivery to the ventral hippocampus can rescue some of the mutant behaviors, while intracerebroventricular delivery, completely recovers the Flailer animal phenotype associated to anxiety and ASD. Conclusions: Our results demonstrate the potential of DN-CRISPR to efficiently remove larger genomic duplications, working as a new gene therapy approach for treating neurodegenerative diseases. © 2023, BioMed Central Ltd., part of Springer Nature.
Fast rotating blue stragglers prefer loose clusters
(Nature Research, 0023-12) Ferraro, Francesco R; Mucciarelli, Alessio; Lanzoni, Barbara; Pallanca, Cristina; Cadelano, Mario; Billi, Alex; Sills, Alison; Vesperini, Enrico; Dalessandro, Emanuele; Beccari, Giacomo; Monaco, Lorenzo; Mateo, Mario
Blue stragglers are anomalously luminous core hydrogen-burning stars formed through mass-transfer in binary/triple systems and stellar collisions. Their physical and evolutionary properties are largely unknown and unconstrained. Here we analyze 320 high-resolution spectra of blue stragglers collected in eight galactic globular clusters with different structural characteristics and show evidence that the fraction of fast rotating blue stragglers (with rotational velocities larger than 40 km/s) increases for decreasing central density of the host system. This trend suggests that fast spinning blue stragglers prefer low-density environments and promises to open an unexplored route towards understanding the evolutionary processes of these stars. Since large rotation rates are expected in the early stages of both formation channels, our results provide direct evidence for recent blue straggler formation activity in low-density environments and put strong constraints on the timescale of the collisional blue straggler slow-down processes. © 2023, The Author(s).
Reduced microbial diversity of the nasopharyngeal microbiome in household contacts with latent tuberculosis infection
(Nature Research, 0023-12) Ruiz-Tagle, Cinthya; Ugalde, Juan A.; Naves, Rodrigo; Araos, Rafael; García, Patricia f; Balcells, María Elvira
The upper respiratory tract is an obliged pathway for respiratory pathogens and a healthy microbiota may support the host's mucosal immunity preventing infection. We analyzed the nasopharyngeal microbiome in tuberculosis household contacts (HHCs) and its association with latent tuberculosis infection (TBI). A prospective cohort of HHCs was established and latent TBI status was assessed by serial interferon-γ release assay (IGRA). Nasopharyngeal swabs collected at baseline were processed for 16S rRNA gene sequencing. The 82 participants included in the analysis were classified as: (a) non-TBI [IGRA negative at baseline and follow-up, no active TB (n = 31)], (b) pre-TBI [IGRA negative at baseline but converted to IGRA positive or developed active TB at follow-up (n = 16)], and (c) TBI [IGRA positive at enrollment (n = 35)]. Predominant phyla were Actinobacteriota, Proteobacteria, Firmicutes and Bacteroidota. TBI group had a lower alpha diversity compared to non-TBI (padj = 0.04) and pre-TBI (padj = 0.04). Only TBI and non-TBI had beta diversity differences (padj = 0.035). Core microbiomes’ had unique genera, and genus showed differential abundance among groups. HHCs with established latent TBI showed reduced nasopharyngeal microbial diversity with distinctive taxonomical composition. Whether a pre-existing microbiome feature favors, are a consequence, or protects against Mycobacterium tuberculosis needs further investigation. © 2023, The Author(s).
Can climate knowledge enable Warragamba Dam, Sydney, Australia to be used to manage flood risk?
(Institute of Physics, 0023-12) Devanand, Anjana; Pitman, Andy J; Carvajal, Guido; Khan, Stuart J
Dams that serve a dual purpose of water supply and flood mitigation operate to maintain a defined full supply level of water that balances the two conflicting requirements. To optimize the use of available storage space, the full supply level may be adjusted to reflect changing risks of future water shortages and future flood inflows based on known seasonal variations and current observations. The Warragamba Dam in eastern Australia is located upstream of the populated Hawkesbury-Nepean valley which has one of the largest flood exposures in the country. However, the operating protocol of the reservoir does not include provisions to reduce the full supply level of the dam for flood mitigation. Large scale climate indicators that are known to influence the hydroclimate of this region may potentially contain useful information to inform the dual use of this reservoir, but their utility for this purpose has not been studied. Here we explore whether current observations of large-scale climate along with antecedent catchment conditions can be used to estimate the probability of large inflows into the reservoir in the next 3- and 6 months, to aid flood management. We find that the predictors have a substantial influence on the probability of large inflows. The probability differences during opposite predictor phases vary by season and range from 30% to 70%. Our results indicate that considering current climate information to inform dual use of the Warragamba dam has merit. © 2023 The Author(s). Published by IOP Publishing Ltd.
Ursodeoxycholic acid induces sarcopenia associated with decreased protein synthesis and autophagic flux
(BioMed Central Ltd, 0023-12) Orozco-Aguilar, Josué; Tacchi, Franco; Aguirre, Francisco; Valero-Breton, Mayalen; Castro-Sepulveda, Mauricio; Simon, Felipe; Cabello-Verrugio, Claudio
Background: Skeletal muscle generates force and movements and maintains posture. Under pathological conditions, muscle fibers suffer an imbalance in protein synthesis/degradation. This event causes muscle mass loss and decreased strength and muscle function, a syndrome known as sarcopenia. Recently, our laboratory described secondary sarcopenia in a chronic cholestatic liver disease (CCLD) mouse model. Interestingly, the administration of ursodeoxycholic acid (UDCA), a hydrophilic bile acid, is an effective therapy for cholestatic hepatic alterations. However, the effect of UDCA on skeletal muscle mass and functionality has never been evaluated, nor the possible involved mechanisms. Methods: We assessed the ability of UDCA to generate sarcopenia in C57BL6 mice and develop a sarcopenic-like phenotype in C2C12 myotubes and isolated muscle fibers. In mice, we measured muscle strength by a grip strength test, muscle mass by bioimpedance and mass for specific muscles, and physical function by a treadmill test. We also detected the fiber’s diameter and content of sarcomeric proteins. In C2C12 myotubes and/or isolated muscle fibers, we determined the diameter and troponin I level to validate the cellular effect. Moreover, to evaluate possible mechanisms, we detected puromycin incorporation, p70S6K, and 4EBP1 to evaluate protein synthesis and ULK1, LC3 I, and II protein levels to determine autophagic flux. The mitophagosome-like structures were detected by transmission electron microscopy. Results: UDCA induced sarcopenia in healthy mice, evidenced by decreased strength, muscle mass, and physical function, with a decline in the fiber’s diameter and the troponin I protein levels. In the C2C12 myotubes, we observed that UDCA caused a reduction in the diameter and content of MHC, troponin I, puromycin incorporation, and phosphorylated forms of p70S6K and 4EBP1. Further, we detected increased levels of phosphorylated ULK1, the LC3II/LC3I ratio, and the number of mitophagosome-like structures. These data suggest that UDCA induces a sarcopenic-like phenotype with decreased protein synthesis and autophagic flux. Conclusions: Our results indicate that UDCA induces sarcopenia in mice and sarcopenic-like features in C2C12 myotubes and/or isolated muscle fibers concomitantly with decreased protein synthesis and alterations in autophagic flux. © 2023, The Author(s).
Ontogenetically distinct neutrophils differ in function and transcriptional profile in zebrafish
(Nature Research, 0023-12) García-López, Juan P.; Grimaldi, Alexandre; Chen, Zelin; Meneses, Claudio; Bravo-Tello, Karina; Bresciani, Erica; Banderas, Alvaro; Burgess, Shawn M.; Hernández, Pedro P; Feijoo, Carmen G
The current view of hematopoiesis considers leukocytes on a continuum with distinct developmental origins, and which exert non-overlapping functions. However, there is less known about the function and phenotype of ontogenetically distinct neutrophil populations. In this work, using a photoconvertible transgenic zebrafish line; Tg(mpx:Dendra2), we selectively label rostral blood island-derived and caudal hematopoietic tissue-derived neutrophils in vivo during steady state or upon injury. By comparing the migratory properties and single-cell expression profiles of both neutrophil populations at steady state we show that rostral neutrophils show higher csf3b expression and migration capacity than caudal neutrophils. Upon injury, both populations share a core transcriptional profile as well as subset-specific transcriptional signatures. Accordingly, both rostral and caudal neutrophils are recruited to the wound independently of their distance to the injury. While rostral neutrophils respond uniformly, caudal neutrophils respond heterogeneously. Collectively, our results reveal that co-existing neutrophils populations with ontogenically distinct origin display functional differences. © 2023, Springer Nature Limited.
Surgical timing prevails as the main factor over morphologic characteristics in the reduction by ligamentotaxis of thoracolumbar burst fractures
(BioMed Central Ltd, 0023-12) Cirillo, Juan Ignacio; Farias, Ignacio; Del Pino, Cristóbal; Gimbernat, Marcos; Urzúa, Alejandro; Tapia, Carlos; Zamorano, Juan José
Background: thoracolumbar burst fractures are associated with spinal canal occupation. The indirect decompression of the spinal canal and reduction of the fragment can be achieved with the distraction of the middle column and ligamentotaxis. Nevertheless, the factors that influence the effectiveness of this procedure and its temporality are controversial. Methods: The aim of this observational, cross-sectional study was to evaluate the effectiveness of indirect reduction by ligamentotaxis in thoracolumbar burst fractures according to the fracture’s radiologic characteristics and the procedure’s temporality. Patients diagnosed with a thoracolumbar burst fracture between 2010 and 2021 were submitted to indirect reduction by distraction and ligamentotaxis. A retrospective analysis of radiologic characteristics and temporality of the procedure was performed with an independent sample t-test or Pearson’s correlation coefficient, as required. Results: A total of 58 patients were included in the analysis. Postoperatively, ligamentotaxis significantly improved all radiologic parameters (canal occupation, endplates distance, and vertebra height). Still, none of the radiological characteristics of the fracture (width, height, position, sagittal angle) were associated with the postoperative change in canal occupation. The endplates distance and the temporality of ligamentotaxis significantly predicted the reduction of the fracture. Conclusion: Fragment reduction effectiveness is more significant when performed as early as possible and adequate distraction is achieved using the internal fixator system. The radiologic characteristics of the fractured fragment do not determine its reduction capacity. © 2023, The Author(s).
Considering a Bifactor Model of Children’s Subjective Well-Being Using a Multinational Sample
(Springer Science and Business Media B.V., 0023-12) Savahl, Shazly; Casas, Ferran; Adams, Sabirah
In the current study, we consider the viability of a bifactor model of children’s subjective well-being (SWB) by contributing to the discussion on the dimensionality of children’s SWB. We specify a general factor of SWB and four group factors (context-free cognitive life satisfaction, domain-based cognitive life satisfaction, positive affect, and negative affect) using structural equation modelling and parceling. We used data from the Children’s Worlds International Survey of Children’s Well-Being (N = 92 782). Our analysis strategy included confirmatory factor analysis and bifactor analysis. We found a good fit for the specified bifactor model, with all items loading onto a general factor and group factors. For the bifactor analysis, after controlling for the general factor, the loadings on the group factors were substantially lower, and did not meet the criteria of acceptability for bifactor indices thresholds. The common variance of the items is largely explained by the general factor; thus, the specification of the group factors cannot be justified. Further, we found an excellent fit for a model using the parceling approach. From a measurement perspective, the construct of children’s SWB can potentially be measured as a unidimensional construct. Thus, it may be feasible to report a total score for children’s SWB, as opposed to scores on the individual subscales (group factors). Applied researchers can thus confidently use SWB as a unidimensional construct or follow the parceling approach in the structural equation model context. © 2023, The Author(s).
EFFECTS OF PLYOMETRIC JUMP TRAINING ON RUNNING ECONOMY IN ENDURANCE RUNNERS: A SYSTEMATIC REVIEW AND META-ANALYSIS
(University of Zagreb - Faculty of Kinesiology, 0023-12-31) Barrio, Ekaitz Dudagoitia; Fernández-Landa, Julen; Negra, Yassine; Ramirez-Campillo, Rodrigo; de Alcaraz, Antonio García
Running economy (RE) has a strong relationship with distance running performance and is defined as the energy demand for a given velocity. Plyometric jump training may improve RE. The present study aimed to assess the effects of plyometric jump training on endurance runners’ running economy and to estimate the effectiveness of program duration, training frequency, total sessions, age, training status and velocity. A literature search was performed using PubMed/MEDLINE, Web of Science, and SCOPUS databases. Subgroup and single training factor analyses of program duration, frequency, total sessions, chronological age, training status, and running velocity were performed. A random-effects model for meta-analyses was used. Eighteen studies were selected for the systematic review and 10 for the meta-analysis. A trivial effect was noted for plyometric jump training on running economy (ES=0.19). However, plyometric jump training combined with resistance training revealed a large effect on running economy (ES=1.34). Greater running economy improvements were noted after training interventions with >15 total sessions (ES=1.00), >7 weeks (ES=0.95) and >2 days/week (ES=0.89). The youngest (ES=0.95) and highly trained participants (ES=0.94) with faster velocities (ES=0.95) obtained better results. Our findings highlight the effect of plyometric jump training that may improve running economy, particularly in combination with resistance training, after longerterm interventions (i.e., >15 total sessions, >7 weeks), with greater frequency, and among younger and more highly trained runners, especially during running at higher competitive velocities. © 2023, University of Zagreb - Faculty of Kinesiology. All rights reserved.
Observation of quantum entanglement with top quarks at the ATLAS detector
(Nature Research, 0024-09) Zwalinski L.; Zou W; Zormpa O; Zorbas T.G; Zoch K; Zoccoli A; Živković L.; Ziolkowski M.; Zinsser J.; Zimine N.I.; Zhukov K.; Zhuang X
Entanglement is a key feature of quantum mechanics1–3, with applications in fields such as metrology, cryptography, quantum information and quantum computation4–8. It has been observed in a wide variety of systems and length scales, ranging from the microscopic9–13 to the macroscopic14–16. However, entanglement remains largely unexplored at the highest accessible energy scales. Here we report the highest-energy observation of entanglement, in top–antitop quark events produced at the Large Hadron Collider, using a proton–proton collision dataset with a centre-of-mass energy of √s = 13 TeV and an integrated luminosity of 140 inverse femtobarns (fb)−1 recorded with the ATLAS experiment. Spin entanglement is detected from the measurement of a single observable D, inferred from the angle between the charged leptons in their parent top- and antitop-quark rest frames. The observable is measured in a narrow interval around the top–antitop quark production threshold, at which the entanglement detection is expected to be significant. It is reported in a fiducial phase space defined with stable particles to minimize the uncertainties that stem from the limitations of the Monte Carlo event generators and the parton shower model in modelling top-quark pair production. The entanglement marker is measured to be D = −0.537 ± 0.002 (stat.) ± 0.019 (syst.) for 340GeV

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