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Keywords = Cumulative Link Mixed Model

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17 pages, 1855 KB  
Article
Long-Term Clinical Efficacy of the Disc-FX Procedure in Contained Disc Herniation: A 7-Year Follow-Up from a Single-Center Cohort Study
by Magdalena Rybaczek, Kacper Prokop, Karol Sawicki, Robert Rutkowski, Aleksander Lebejko, Grzegorz Perestret, Zenon Mariak, Paweł Grabala and Tomasz Łysoń
J. Clin. Med. 2025, 14(18), 6378; https://doi.org/10.3390/jcm14186378 - 10 Sep 2025
Viewed by 464
Abstract
Background: Contained lumbar disc herniation is a prevalent cause of chronic low back pain and functional impairment. The Disc-FX system, a minimally invasive, percutaneous technique integrating nucleotomy, nucleus ablation, and annuloplasty, offers a multimodal approach to managing early degenerative disc disease. Despite promising [...] Read more.
Background: Contained lumbar disc herniation is a prevalent cause of chronic low back pain and functional impairment. The Disc-FX system, a minimally invasive, percutaneous technique integrating nucleotomy, nucleus ablation, and annuloplasty, offers a multimodal approach to managing early degenerative disc disease. Despite promising short-term outcomes, evidence regarding long-term effectiveness remains limited. Methods: This single-center cohort study evaluated 197 patients (median age: 48 years; 56.85% female) who underwent the Disc-FX procedure between 2017 and 2024. Patients were followed for up to 84 months. Pain and disability were assessed using a Visual Analog Scale (VAS) and the Oswestry Disability Index (ODI), respectively, while satisfaction was measured by the MacNab criteria. Multivariable models, including cumulative link models and linear mixed-effects models, were used to identify predictors of outcomes. Results: The Disc-FX procedure resulted in significant and sustained improvements in pain and function. Mean VAS scores decreased from 7.79 preoperatively to 4.31 at 12 months and remained below baseline at 84 months (5.05). ODI scores improved from 15.43 preoperatively to 9.62 at 36 months, rising slightly to 12.75 at 84 months. Good or excellent outcomes were reported in 66.9% of patients according to MacNab criteria. Male sex (OR = 0.41), longer symptom duration (OR = 0.85), and presence of radicular symptoms (OR = 0.39) were significantly associated with less favorable outcomes. Reoperation occurred in 26.4% of cases, predominantly within the first year and most frequently at L4/L5. Complications were rare (3.08%). Conclusions: This study provides robust evidence supporting the long-term clinical efficacy of the Disc-FX procedure in selected patients with contained lumbar disc herniation. While overall outcomes are favorable, optimal results depend on early intervention and careful patient selection, particularly in relation to symptom chronicity and the presence of radicular signs. Full article
(This article belongs to the Special Issue New Perspectives in Lumbar Spine Surgery: Treatment and Management)
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12 pages, 2590 KB  
Article
Summer Cafe: In Vitro Case Study of Biological Repellents Against the Large Pine Weevil
by Ilze Matisone, Kristaps Ozoliņš, Roberts Matisons, Mārtiņš Spāde, Uldis Grīnfelds and Rinalds Trukšs
Forests 2025, 16(7), 1139; https://doi.org/10.3390/f16071139 - 10 Jul 2025
Viewed by 334
Abstract
Growing environmental concerns have led to the search for alternative biological repellents against the large pine weevil Hylobius abietis L., Europe’s most important coniferous forest regeneration pest. A laboratory study was carried out to assess the effectiveness (damage intensity) of six combinations of [...] Read more.
Growing environmental concerns have led to the search for alternative biological repellents against the large pine weevil Hylobius abietis L., Europe’s most important coniferous forest regeneration pest. A laboratory study was carried out to assess the effectiveness (damage intensity) of six combinations of a novel biological repellent, consisting of plant-based oils, beeswax, calcium carbonate, vanillin, pine bark extractives, terpentine, abrasive particles, solvent, and a viscosity agent, in comparison with commercially available repellent Norfort LDW 115. The application complexity of the repellents, their persistence on seedlings, and the extent of H. abietis damage were evaluated. The five alternative repellents had higher protection compared to the control repellent, highlighting the potential for new alternative repellents. The base (without additives) repellent provided the highest protection, indicating a redundancy of admixtures. A mixed cumulative link model, employed to estimate differences between the repellents, estimated 85% undamaged and none significantly damaged saplings in the case of the base repellent. However, the consistency and hence persistence of certain repellents on plantlets would benefit from improvements; further field studies are needed to upscale the test of the stability and efficiency of high levels in real environments under different H. abietis population pressures. Full article
(This article belongs to the Section Forest Health)
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11 pages, 1004 KB  
Article
Comparative Analysis of Automated and Handheld Breast Ultrasound Findings for Small (≤1 cm) Breast Cancers Based on BI-RADS Category
by Han Song Mun, Eun Young Ko, Boo-Kyung Han, Eun Sook Ko, Ji Soo Choi, Haejung Kim, Myoung Kyoung Kim and Jieun Kim
Diagnostics 2025, 15(2), 212; https://doi.org/10.3390/diagnostics15020212 - 17 Jan 2025
Viewed by 1642
Abstract
Objectives: This study aimed to compare ultrasound (US) findings between automated and handheld breast ultrasound (ABUS and HHUS, respectively) in small breast cancers, based on the breast imaging reporting and data system (BI-RADS) category. Methods: We included 51 women (mean age: [...] Read more.
Objectives: This study aimed to compare ultrasound (US) findings between automated and handheld breast ultrasound (ABUS and HHUS, respectively) in small breast cancers, based on the breast imaging reporting and data system (BI-RADS) category. Methods: We included 51 women (mean age: 52 years; range: 39–66 years) with breast cancer (invasive or DCIS), all of whom underwent both ABUS and HHUS. Patients with tumors measuring ≤1 cm on either modality were enrolled. Two breast radiologists retrospectively evaluated multiple imaging features, including shape, orientation, margin, echo pattern, and posterior characteristics and assigned BI-RADS categories. Lesion sizes were compared between US and pathological findings. Statistical analyses were performed using Bowker’s test of symmetry, a paired t-test, and a cumulative link mixed model. Results: ABUS assigned lower BI-RADS categories than HHUS while still maintaining malignancy suspicion in categories 4A or higher (54.8% consistent with HHUS; 37.3% downcategorized in ABUS, p = 0.005). While ABUS demonstrated less aggressive margins in some cases (61.3% consistent with HHUS; 25.8% showing fewer suspicious margins in ABUS), this difference was not statistically significant (p = 0.221). Similarly, ABUS exhibited slightly greater height–width ratios compared to HHUS (median, interquartile range: 0.98, 0.7–1.12 vs. 0.86, 0.74–1.10, p = 0.166). No significant differences were observed in other US findings or tumor sizes between the two modalities (all p > 0.05). Conclusions: Small breast cancers exhibited suspicious US features on both ABUS and HHUS, yet they were assigned lower BI-RADS assessment categories on ABUS compared to HHUS. Therefore, when conducting breast cancer screening with ABUS, it is important to remain attentive to even subtle suspicious findings, and active consideration for biopsy may be warranted. Full article
(This article belongs to the Special Issue Recent Advances in Breast Imaging)
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13 pages, 15834 KB  
Article
Human–Environment Interactions Shape Mosquito Seasonal Population Dynamics
by Laura Blanco-Sierra, Jesús Bellver-Arnau, Santi Escartin, Simone Mariani and Frederic Bartumeus
Insects 2024, 15(7), 527; https://doi.org/10.3390/insects15070527 - 12 Jul 2024
Cited by 5 | Viewed by 3369
Abstract
Mosquito species, including the Asian tiger mosquito, can transmit disease-causing pathogens such as dengue, Zika, and chikungunya, with their population dynamics influenced by a variety of factors including climate shifts, human activity, and local environmental conditions. Understanding these dynamics is vital for effective [...] Read more.
Mosquito species, including the Asian tiger mosquito, can transmit disease-causing pathogens such as dengue, Zika, and chikungunya, with their population dynamics influenced by a variety of factors including climate shifts, human activity, and local environmental conditions. Understanding these dynamics is vital for effective control measures. Our study, conducted in Jardí Botanic Marimurtra from May to November 2021, monitored Ae. albopictus activity using BG-Traps and investigated larval control effects. We employed Generalized Linear Mixed Models to analyze variables like weather, human presence, and larvicidal control on adult mosquito abundance. Adults of Ae. albopictus exhibited a seasonal pattern influenced by temperature but with bimodal peaks linked to cumulative rainfall. Proximity to stagnant water and visitor influx directly affected mosquito captures. Additionally, the effectiveness of larvicide treatments depended on interactions between preceding rainfall levels and treatment timing. Our research emphasizes the significance of studying vector ecology at local scales to enhance the efficacy of control programs and address the escalating burden of vector-borne diseases. Considering the impacts of extreme weather events and climate shifts is essential for the development of robust vector control strategies. Furthermore, our distinct findings serve as a prime illustration of utilizing statistical modeling to gain mechanistic insights into ecological patterns and processes. Full article
(This article belongs to the Special Issue Climate Sensitive Ecological and Dynamical Models of Insects)
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11 pages, 285 KB  
Article
Assessment of Resistance of Barley Varieties to Diseases in Polish Organic Field Trials
by Tomasz Lenartowicz, Henryk Bujak, Marcin Przystalski, Inna Mashevska, Kamila Nowosad, Krzysztof Jończyk and Beata Feledyn-Szewczyk
Agriculture 2024, 14(5), 789; https://doi.org/10.3390/agriculture14050789 - 20 May 2024
Cited by 3 | Viewed by 1644
Abstract
Leaf rust and net blotch are two important fungal diseases of barley. Leaf rust is the most important rust disease of barley, whereas net blotch can result in significant yield losses and cause the deterioration of crop quality. The best and the most [...] Read more.
Leaf rust and net blotch are two important fungal diseases of barley. Leaf rust is the most important rust disease of barley, whereas net blotch can result in significant yield losses and cause the deterioration of crop quality. The best and the most environmentally friendly method to control diseases is to cultivate resistant varieties. The aim of the current study was to identify barley varieties with an improved resistance to leaf rust and net blotch in Polish organic post-registration trials conducted in the years 2020–2022. For this purpose, the cumulative link mixed model with several variance components was applied to model resistance to leaf rust and net blotch. It was found that the reference variety Radek was the most resistant to leaf rust, whereas variety Avatar outperformed the reference variety in terms of resistance to net blotch, although the difference between the two varieties was non-significant. In the present study, the use of the cumulative link mixed model framework made it possible to calculate cumulative probabilities or the probability of a given score for each variety and disease, which might be useful for plant breeders and crop experts. Both, the method of analysis and resistant varieties may be used in the breeding process to derive new resistant varieties suitable for the organic farming system. Full article
(This article belongs to the Section Crop Protection, Diseases, Pests and Weeds)
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25 pages, 8968 KB  
Article
Assessment of Gas Production from Complex Hydrate System in Qiongdongnan Basin of South China Sea
by Lu Yu, Hongfeng Lu, Liang Zhang, Chenlu Xu, Zenggui Kuang, Xian Li, Han Yu and Yejia Wang
Energies 2023, 16(21), 7447; https://doi.org/10.3390/en16217447 - 4 Nov 2023
Cited by 3 | Viewed by 1774
Abstract
The China Geological Survey (CGS) has carried out a large number of surveys and core drilling over the deepwater area of Qiongdongnan Basin (QDNB) in the South China Sea and discovered the natural gas hydrate system controlled by the gas chimney with a [...] Read more.
The China Geological Survey (CGS) has carried out a large number of surveys and core drilling over the deepwater area of Qiongdongnan Basin (QDNB) in the South China Sea and discovered the natural gas hydrate system controlled by the gas chimney with a high geothermal gradient. The complex hydrate system consists of a sandy hydrate reservoir distributed around a lateral transition gas-hydrate mixed zone and a free gas zone in the middle. The hydrate and gas are distributed in the same layer, which is thin but potentially valuable for commercial exploitation. In this paper, a geological model of the target hydrate system in QDNB was established based on the results of several rounds of drilling. The method of numerical simulation was utilized to assess the production capacity of the target hydrate system and clarify the evolution of hydrate and gas saturation distribution with different well positions. The simulation results indicate that the producer well built in the center of the highly-saturated hydrate zone has a limited gas production capacity, with a cumulative production of only 7.25 × 106 m3 in 9 years. The well built at the boundary of the hydrate zone can rapidly link up the gas in the transition zone through a large production pressure differential, but it lacks control over the hydrates and its dissociated gas in the transition zone—the cumulative gas production volume from hydrate accounts for only 12.3%. As for the wells built in the transition zone and gas zone, they can directly invoke the free gas production capacity. Free gas is produced as the formation pressure reduces and hydrate is induced to dissociate, making the gas from the hydrate the subsequent production capacity. The cumulative production can exceed 6 × 108 m3 in 9 years. The stable production duration can extend to 2645 days, and the cumulative proportion of gas at the wellhead from hydrate reaches close to 30%. It is necessary to avoid the free water layer. The bottom water coning would improve the water production by 40% and shorten the stable production duration. In summary, the complex hydrate system of this type in the QDNB has the potential for industrialized exploitation. In the future, the well group can be used for the further improvement of the hydrate utilization rate. Full article
(This article belongs to the Special Issue Gas Hydrates: A Future Clean Energy Resource)
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16 pages, 3738 KB  
Article
Co-Exposure of Polycyclic Aromatic Hydrocarbons and Phthalates with Blood Cell-Based Inflammation in Early Pregnant Women
by Yunxiao Yang, Ting Wang, Lei Luo, Qian He, Fangfei Guo, Zhongbao Chen, Yijun Liu, Xingyan Liu, Yan Xie, Xuejun Shang, Xubo Shen, Yuanzhong Zhou and Kunming Tian
Toxics 2023, 11(10), 810; https://doi.org/10.3390/toxics11100810 - 25 Sep 2023
Cited by 9 | Viewed by 2372
Abstract
Cumulative evidence has demonstrated that exposure to polycyclic aromatic hydrocarbons (PAHs) or phthalates (PAEs) contributes to a variety of adverse health effects. However, the association of PAHs and PAEs co-exposure with blood cell-based inflammatory indicators during early pregnancy is still unclear. We aimed [...] Read more.
Cumulative evidence has demonstrated that exposure to polycyclic aromatic hydrocarbons (PAHs) or phthalates (PAEs) contributes to a variety of adverse health effects. However, the association of PAHs and PAEs co-exposure with blood cell-based inflammatory indicators during early pregnancy is still unclear. We aimed to investigate the single and mixed associations of exposure to PAHs and PAEs with blood cell-based inflammatory indicators among early pregnant women. A total of 318 early pregnant women were included in this study. General linear regressions were used to estimate the relationships of individual OH-PAHs and mPAEs with blood cell-based inflammatory indicators. The key pollutants were selected by an adapted least absolute shrinkage and selection operator (LASSO) penalized regression model and wasemployed to build the Bayesian kernel machine regression (BKMR) and quantile g-computation (Q-g) models, which can assess the joint association of OH-PAHs and mPAEs with blood cell-based inflammatory indicators. General linear regression indicated that each 1% increase in MOP was associated with a 4.92% (95% CI: 2.12%, 7.68%), 3.25% (95% CI: 0.50%, 6.18%), 5.87% (95% CI: 2.22%, 9.64%), and 6.50% (95% CI: 3.46%, 9.64%) increase in WBC, lymphocytes, neutrophils, and monocytes, respectively. BKMR and Q-g analysis showed that the mixture of OH-PAHs and mPAEs was linked with increased levels of white blood cells (WBC), neutrophils, monocytes, and lymphocytes, and MOP was identified as the dominant contributor. OH-PAHs and mPAEs co-exposure in early pregnancy was associated with elevated blood cell-based inflammatory indicators reactions. More attention should be paid to the inflammation induced by environmental pollution for perinatal women, especially early pregnant women. Full article
(This article belongs to the Special Issue Environmental Exposure and Reproductive Health)
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19 pages, 524 KB  
Article
Therapeutic Drug Monitoring in Children and Adolescents: Findings on Fluoxetine from the TDM-VIGIL Trial
by Michael Frey, Lukasz Smigielski, Elvira Tini, Stefanie Fekete, Christian Fleischhaker, Christoph Wewetzer, Andreas Karwautz, Christoph U. Correll, Manfred Gerlach, Regina Taurines, Paul L. Plener, Uwe Malzahn, Selina Kornbichler, Laura Weninger, Matthias Brockhaus, Su-Yin Reuter-Dang, Karl Reitzle, Hans Rock, Hartmut Imgart, Peter Heuschmann, Stefan Unterecker, Wolfgang Briegel, Tobias Banaschewski, Jörg M. Fegert, Tobias Hellenschmidt, Michael Kaess, Michael Kölch, Tobias Renner, Christian Rexroth, Susanne Walitza, Gerd Schulte-Körne, Marcel Romanos and Karin Maria Egbertsadd Show full author list remove Hide full author list
Pharmaceutics 2023, 15(9), 2202; https://doi.org/10.3390/pharmaceutics15092202 - 25 Aug 2023
Cited by 3 | Viewed by 4170
Abstract
Fluoxetine is the recommended first-line antidepressant in many therapeutic guidelines for children and adolescents. However, little is known about the relationships between drug dose and serum level as well as the therapeutic serum reference range in this age group. Within a large naturalistic [...] Read more.
Fluoxetine is the recommended first-line antidepressant in many therapeutic guidelines for children and adolescents. However, little is known about the relationships between drug dose and serum level as well as the therapeutic serum reference range in this age group. Within a large naturalistic observational prospective multicenter clinical trial (“TDM-VIGIL”), a transdiagnostic sample of children and adolescents (n = 138; mean age, 15; range, 7–18 years; 24.6% males) was treated with fluoxetine (10–40 mg/day). Analyses of both the last timepoint and all timepoints (n = 292 observations), utilizing (multiple) linear regressions, linear mixed-effect models, and cumulative link (mixed) models, were used to test the associations between dose, serum concentration, outcome, and potential predictors. The receiver operating curve and first to third interquartile methods, respectively, were used to examine concentration cutoff and reference values for responders. A strong positive relationship was found between dose and serum concentration of fluoxetine and its metabolite. Higher body weight was associated with lower serum concentrations, and female sex was associated with lower therapeutic response. The preliminary reference ranges for the active moiety (fluoxetine+norfluoxetine) were 208–328 ng/mL (transdiagnostically) and 201.5–306 ng/mL (depression). Most patients showed marked (45.6%) or minimal (43.5%) improvements and reported no adverse effects (64.9%). This study demonstrated a clear linear dose–serum level relationship for fluoxetine in youth, with the identified reference range being within that established for adults. Full article
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21 pages, 805 KB  
Article
Optimal Choice between Defined Contribution and Cash Balance Pension Schemes: Balancing Interests of Employers and Workers
by Vanessa Hanna and Pierre Devolder
Risks 2023, 11(7), 135; https://doi.org/10.3390/risks11070135 - 21 Jul 2023
Cited by 1 | Viewed by 1597
Abstract
In the context of pension plans, the employer and the worker have distinct interests and face different risks. The worker seeks higher retirement benefits, while the employer aims to minimize the cost of fulfilling his obligations. To address these diverse needs, the defined [...] Read more.
In the context of pension plans, the employer and the worker have distinct interests and face different risks. The worker seeks higher retirement benefits, while the employer aims to minimize the cost of fulfilling his obligations. To address these diverse needs, the defined contribution plan managed with participating life insurance (DC-PL) and the cash balance plan managed with unit-linked insurance (CB-UL) serve as suitable choices. The multi-criteria analysis is conducted using the cumulative prospect theory model to measure the utility of the parties involved toward a mixed product combining these two pension plans. By assigning weights to risk measures and maximizing utilities, the paper employs both additive utility and Nash equilibrium approaches. The results reveal that the CB-UL plan aligns with employers’ interests, offering potential financial gains, while the DC-PL plan attracts workers due to its profit-sharing aspect. Significantly, when equal importance is given to both parties, the CB-UL plan emerges as the prevailing choice. This study contributes to the understanding of pension plan design and decision-making dynamics between employers and workers, providing valuable insights for achieving a balance between retirement benefits and cost management. Full article
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15 pages, 1044 KB  
Article
Exploring the Predictive Potential of Physiological Measures of Human Thermal Strain in Outdoor Environments in Hot and Humid Areas in Summer—A Case Study of Shanghai, China
by Zefeng Lian, Binyi Liu and Robert D. Brown
Int. J. Environ. Res. Public Health 2023, 20(6), 5017; https://doi.org/10.3390/ijerph20065017 - 12 Mar 2023
Viewed by 2383
Abstract
Whenever people spend time outdoors during hot weather, they are putting themselves in potentially stressful situations. Being able to predict whether a person is overheating can be critical in preventing heat-health issues. There is a clear relationship between body core temperature and heat [...] Read more.
Whenever people spend time outdoors during hot weather, they are putting themselves in potentially stressful situations. Being able to predict whether a person is overheating can be critical in preventing heat-health issues. There is a clear relationship between body core temperature and heat health. However, measuring body core temperature is expensive. Identifying a non-invasive measure that could indicate a person’s thermal strain would be valuable. This study investigated five physiological measures as possible surrogates: finger mean skin temperature (FSKT), finger maximum skin temperature (FMSKT), skin conductance level (SCL), heart rate (HR), and heart rate variability (HRV). Furthermore, they were compared against the results of participants’ subjective thermal sensation and thermal comfort in a range of hot microclimatic conditions in a hot and humid climate. Results showed that except for SCL, each of the other four physiological measures had a positive significant relationship with thermal sensation, but a negative relationship with thermal comfort. Furthermore, through testing by cumulative link mixed models, HRV was found to be the most suitable surrogate for predicting thermal sensation and thermal comfort through a simple, non-invasive measure in outdoor environment in summer in a hot and humid area. This study highlights the method for predicting human thermal strain and contributes to improve the public health and well-being of urban dwellers in outdoor environments. Full article
(This article belongs to the Special Issue Thermal Comfort and Safety)
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27 pages, 1261 KB  
Article
Multi-Level Analysis of Learning Management Systems’ User Acceptance Exemplified in Two System Case Studies
by Parisa Shayan, Roberto Rondinelli, Menno van Zaanen and Martin Atzmueller
Data 2023, 8(3), 45; https://doi.org/10.3390/data8030045 - 22 Feb 2023
Cited by 9 | Viewed by 4764
Abstract
There has recently been an increasing interest in Learning Management Systems (LMSs). It is currently unclear, however, exactly how these systems are perceived by their users. This article analyzes data on user acceptance for two LMSs (Blackboard and Canvas). The respective data are [...] Read more.
There has recently been an increasing interest in Learning Management Systems (LMSs). It is currently unclear, however, exactly how these systems are perceived by their users. This article analyzes data on user acceptance for two LMSs (Blackboard and Canvas). The respective data are collected using a questionnaire modeled after the Technology Acceptance Model (TAM); it relates several variables that influence system acceptability, allowing for a detailed analysis of the system acceptance. We present analyses at two levels of the questionnaire data: questions and constructs (taken from TAM) as well as on different analysis levels using targeted methods. First, we investigate the differences between the above LMSs using statistical tests (t-test). Second, we provide results at the question level using descriptive indices, such as the mean and the Gini heterogeneity index, and apply methods for ordinal data using the Cumulative Link Mixed Model (CLMM). Next, we apply the same approach at the TAM construct level plus descriptive network analysis (degree centrality and bipartite motifs) to explore the variability of users’ answers and the degree of users’ satisfaction considering the extracted patterns. In the context of TAM, the statistical model is able to analyze LMS acceptance on the question level. As we are also very much interested in identifying LMS acceptance at the construct level, in this article, we provide both statistical analysis as well as network analysis to explore the connection between questionnaire data and relational data. A network analysis approach is particularly useful when analyzing LMS acceptance on the construct level, as this can take the structure of the users’ answers across questions per construct into account. Taken together, these results suggest a higher rate of user acceptance among Canvas users compared to Blackboard both for the question and construct level. Likewise, the descriptive network modeling for Canvas indicates a slightly higher concordance between Canvas users than Blackboard at the construct level. Full article
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17 pages, 6120 KB  
Article
A Mixed FSO/RF Integrated Satellite-High Altitude Platform Relaying Networks for Multiple Terrestrial Users with Presence of Eavesdropper: A Secrecy Performance
by Kehinde O. Odeyemi and Pius A. Owolawi
Photonics 2022, 9(1), 32; https://doi.org/10.3390/photonics9010032 - 4 Jan 2022
Cited by 14 | Viewed by 3493
Abstract
In this paper, the secrecy performance of a mixed free space optical (FSO)/radio frequency (RF) integrated satellite-high altitude platform (HAP) relaying networks for terrestrial multiusers with the existence of an eavesdropper is investigated. In this network, FSO is adopted to establish the link [...] Read more.
In this paper, the secrecy performance of a mixed free space optical (FSO)/radio frequency (RF) integrated satellite-high altitude platform (HAP) relaying networks for terrestrial multiusers with the existence of an eavesdropper is investigated. In this network, FSO is adopted to establish the link between the satellite and HAP for which it experiences Gamma-Gamma distributions under different detection schemes (i.e., heterodyne and intensity modulation direct detection). The transmission between the amplify-and-forward (AF) relaying HAP and terrestrial multiusers is through the RF and is modeled as shadowed-Rician fading distribution. Owning to broadcasting nature of RF link, it is assumed that an eavesdropper attempts to intercept the users’ confidential message, and the eavesdropper link is subjected to Rician distributions. Specifically, the closed-form expression for the system equivalent end-to-end cumulative distribution function is derived by exploiting the Meijer’s G and Fox’s H functions. Based on this expression, the exact closed-form expressions of the system connection outage probability, secrecy outage probability, and strictly positive secrecy capacity are obtained under the different detection schemes at HAP. Moreover, the asymptotic analyze of the system secrecy outage probability is provided to obtain more physical insights. Furthermore, the accuracy of all the derived analytical closed-form expressions is verified through the Monte-Carlo simulations. In addition, the impact of atmospheric turbulence, pointing errors, shadowing severity parameters, and Rician factor are thoroughly evaluated. Under the same system conditions, the results depict that heterodyne detection outperforms the intensity modulation direct detection. Full article
(This article belongs to the Special Issue Optical Wireless Communication (OWC) Systems)
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16 pages, 2580 KB  
Article
Short-Term Cumulative Exposure to Ambient Traffic-Related Black Carbon and Blood Pressure: MMDA Traffic Enforcers’ Health Study
by Zypher Jude G. Regencia, Godofreda V. Dalmacion, Antonio D. Ligsay and Emmanuel S. Baja
Int. J. Environ. Res. Public Health 2021, 18(22), 12122; https://doi.org/10.3390/ijerph182212122 - 18 Nov 2021
Cited by 6 | Viewed by 5579
Abstract
Exposure to traffic-related air pollution is linked with acute alterations in blood pressure (BP). We examined the cumulative short-term effect of black carbon (BC) exposure on systolic (SBP) and diastolic (DBP) BP and assessed effect modification by participant characteristics. SBP and DBP were [...] Read more.
Exposure to traffic-related air pollution is linked with acute alterations in blood pressure (BP). We examined the cumulative short-term effect of black carbon (BC) exposure on systolic (SBP) and diastolic (DBP) BP and assessed effect modification by participant characteristics. SBP and DBP were repeatedly measured on 152 traffic enforcers. Using a linear mixed-effects model with random intercepts, quadratic (QCDL) and cubic (CCDL) constrained distributed lag models were fitted to estimate the cumulative effect of BC concentration on SBP and DBP during the 10 hours (daily exposure) and 7 days (weekly exposure) before the BP measurement. Ambient BC was related to increased BP with QCDL models. An interquartile range change in BC cumulative during the 7 days before the BP measurement was associated with increased BP (1.2% change in mean SBP, 95% confidence interval (CI), 0.1 to 2.3; and 0.5% change in mean DBP, 95% CI, −0.8 to 1.7). Moreover, the association between the 10-h cumulative BC exposure and SBP was stronger for female (4.0% change, 95% CI: 2.1–5.9) versus male and for obese (2.9% change, 95% CI: 1.0–4.8) vs. non-obese traffic enforcers. Short-term cumulative exposure to ambient traffic-related BC could bring about cardiovascular diseases through mechanisms involving increased BP. Full article
(This article belongs to the Special Issue Advances in Airborne Pollution and Human Exposure Research)
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22 pages, 628 KB  
Review
Temperament and Academic Achievement in Children: A Meta-Analysis
by Dalia Nasvytienė and Tomas Lazdauskas
Eur. J. Investig. Health Psychol. Educ. 2021, 11(3), 736-757; https://doi.org/10.3390/ejihpe11030053 - 12 Jul 2021
Cited by 16 | Viewed by 8486
Abstract
This study aimed to systematize the diverse and rather controversial findings of empirical research on the relationship between the temperament and academic achievement of school children, as well as to determine the average effect size between these variables. We included 57 original studies [...] Read more.
This study aimed to systematize the diverse and rather controversial findings of empirical research on the relationship between the temperament and academic achievement of school children, as well as to determine the average effect size between these variables. We included 57 original studies of published and unpublished research conducted in 12 countries between 1985 and 2019, with cumulative sample size of 79,913 (varying from 6333 to 14,126 for links between particular temperament dimensions and specific domains of achievement). A random-effects and mixed-effects model was fitted to the data for the central tendency of the temperament–achievement relation and for analyzing moderators, respectively. The high heterogeneity of studies was tackled by selected specific moderators, namely, education level, transition status, family’s socio-economic level, and sources of report on achievement and temperament. The main findings of this meta-analysis affirmed the positive association of effortful control (EC) and inverse relationship of negative affectivity (NA) with a child’s academic performance, together with no apparent trend of surgency (SU) in this relationship; additionally, the sources of report significantly moderated the link between temperament and academic achievement. Full article
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11 pages, 519 KB  
Article
Performance Analysis of Dual-Hop Mixed Power Line Communication/Free-Space Optical Cooperative Systems
by Manh Le-Tran and Sunghwan Kim
Photonics 2021, 8(6), 230; https://doi.org/10.3390/photonics8060230 - 21 Jun 2021
Cited by 7 | Viewed by 2664
Abstract
In this paper, we study a mixed cooperative communication system consisting of power line communication (PLC) and free-space optical communication (FSO) links, where the PLC link suffers from log-normal fading and is affected by both impulsive and background noises. Meanwhile, the FSO link [...] Read more.
In this paper, we study a mixed cooperative communication system consisting of power line communication (PLC) and free-space optical communication (FSO) links, where the PLC link suffers from log-normal fading and is affected by both impulsive and background noises. Meanwhile, the FSO link undergoes Gamma-Gamma fading with both atmospheric turbulence and pointing errors. More specifically, we present closed-form expressions for the probability density function and the cumulative distribution function of the end-to-end signal-to-noise ratio of the proposed model. Consequently, the outage probability and the bit error rate (BER) performance are derived in terms of univariate Fox-H and bivariate Fox-H functions. Finally, the analytical results are verified using Monte Carlo simulations, providing useful insights into the capabilities of the proposed system. Full article
(This article belongs to the Special Issue Optical Wireless Communications Systems)
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