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Abstract—Powders and ceramic composite materials in an Al2O3–ZrO2 system with a concentration of ZrO2 of 20 wt % are obtained. The effect of introduction of chromium oxide and yttrium oxide into Al2O3–ZrO2 ceramic materials on the phase composition, porosity, microstructure, and mechanical properties is studied. It is shown that the introduction of chromium oxide leads to the improvement of sintering and mechanical properties of the ceramic. Products with the predefined shape of a corresponding computer model are obtained by 3D printing, and also their multistage thermal treatment is carried out. Densely sintered ceramic materials are obtained at 1550 and 1600°C, the open porosity of which is below 1% and microhardness is up to 1646 ± 50 HV. The samples are characterized by a dense microstructure with the grain size of zirconium dioxide from 400 nm to 2 μm and of aluminum oxide from 800 nm to 3 μm. The thickness of the layer formed during 3D printing shows a positive impact of the addition of Cr2O3 on the resolution during 3D printing. [ABSTRACT FROM AUTHOR]

Aim: To determine the effects of obesity in childhood on SARS‐CoV‐2 infection. Methods: A population‐based, cross‐sectional study combining the Israeli Growth Survey and COVID‐19 data for children with at least one SARS‐CoV‐2 test from 16 February 2020 to 20 December 2021. Overweight and obesity status were based on body mass index and the Center for Disease Control criteria. Multivariate logistics regression was performed to validate reliability for weight categories at the age of approximately 6 years compared with weights at approximately 12 years. Results: A total of 444 868 records for children with an overall positivity rate of 22% were studied. The mean age was 9.5 years. The odds ratios of children with obesity or overweight after controlling for sex at 6 years to test positive were 1.07–1.12 and 1.06–1.08 (depending on the model), respectively, compared to those with healthy range body mass index. Conclusion: Excess weight appears to increase the risk of SARS‐CoV‐2 infection. This finding should be considered for public health planning. For example, children with overweight and obesity should be prioritised for vaccination. Excess weight in childhood can be harmful at a young age and not only for long‐term health. [ABSTRACT FROM AUTHOR]

In this article, we have studied the influence of Mn2+ on the properties (phase composition, porosity, microstructure, three-point bending strength, and microhardness) and sintering of the ZrO2–Al2O3–SiO2 composite ceramic materials. The ZrO2–Al2O3–SiO2 ceramic powder containing 2.5 wt % Al2O3 and 0.5 wt % SiO2 with specific area of 24.7 m2/g is synthesized through the coprecipitation method. Three concentrations of Mn2+ are considered: 0.25, 0.50, and 0.75 mol %. The introduction of Mn2+ leads to a significant increase in mechanical properties. The samples are sintered at 1250 and 1300°C for 2 h. The highest value of strength at three-point bending of 761 ± 36 MPa and microhardness of 9.5 ± 0.5 GPa is demonstrated by the material of the composition ZrO2–Al2O3–SiO2 containing 0.75 mol % Mn2+ sintered at 1300°С. The crack resistance of this material is 7.0 MPa m1/2. At the same time, the highest values of crack resistance of 9.3 ± 0.5 MPa m1/2 are shown by materials of the ZrO2–Al2O3–SiO2 composition containing 0.75 mol % Mn2+ sintered at 1250°C. [ABSTRACT FROM AUTHOR]

The paper is devoted to the creation and investigation of the new cement materials formed the new beryite phase (MgHPO4·3H2O) during the setting processes. A cement liquid based on sodium phosphate solution with addition of sodium hyaluronate polymer is used to increase the viscosity and the surface tension in the system and to increase the cohesion of the final product. The effect of cement liquids based on sodium hyaluronate with various concentrations are studied to estimate the phase composition, setting time, pH value, microstructure, injectivity, and strength properties of cement materials. [ABSTRACT FROM AUTHOR]

We have studied calcium sulfate (CS) based cement materials containing up to 5 mol % lithium cations. The presence of lithium ions has been shown to increase the solubility of the CS cements in Dulbecco's solution, which is accompanied by an increase in the pH of extracts from 6.0 to 8.7. Lithium cations were detected in Dulbecco's phosphate buffered saline during the first 24 h of the experiment, and a calcium phosphate layer was formed on the surface of the lithium-containing CS cements during the seventh day. The presence of lithium ions has been shown to cause a twofold decrease in the temperature of the transition from calcium sulfate dihydrate to the hemihydrate. [ABSTRACT FROM AUTHOR]

Using inductively coupled plasma atomic emission spectrometry (ICP-AES) and atomic absorption spectroscopy (AAS), we developed methods that allow express determination of impurity elements (Ag, Cu, Fe, and Zn) with good metrological characteristics in a wide range of concentrations from 0.0005 to 10% in medical materials based on calcium phosphate, without preliminary separation of the matrix and without the use of standard composition samples. The relative standard deviation (Sr) is 0.05–0.005 for the element contents from 1 to 10% and does not exceed 0.15 for the element contents from 0.0005 to 0.1%. New methods of analytical control provided research on the development of composite materials based on substituted calcium phosphate for medical purposes which exhibit antibacterial activity. [ABSTRACT FROM AUTHOR]

Cement materials based on calcium sulfate into which up to 20 mol % of phosphate groups were introduced were obtained in order to improve their cytocompatibility and solubility. It was found that, during exposure of cement materials on the basis of calcium sulfate containing 0, 5, 10, and 20 mol% phosphate groups in model Kokubo solution (simulated body fluid (SBF) simulating the composition of human blood plasma) and Dulbecco's phosphate-buffered saline (DPBS), the formation of a calcium phosphate layer on the surface of the samples was observed in dynamics up to 28 days. In this case, the process of recrystallization of sulfate and phosphate phases was more pronounced in SBF than in DPBS. In in vitro studies on the MG-63 human osteosarcoma line cell culture, cement samples showed cytocompatibility with the presence of moderate matrix surface properties. [ABSTRACT FROM AUTHOR]

The objective of this paper was to estimate the inter-rater reliability of expert assessments of occupational exposures. An inter-rater reliability sub-study was conducted within a population-based case-control study of postmenopausal breast cancer. Detailed information on lifetime occupational histories was obtained from participants and two industrial hygienists assigned exposures to 185 jobs using a checklist of 293 agents. Experts rated exposure for each job–agent combination according to exposure status (unexposed/exposed), confidence that the exposure occurred (possible/probable/definite), intensity (low/medium/high), and frequency (% time per week). The statistical unit of observation was each job–agent assessment (185 jobs × 293 agents = 54,205 assessments per expert). Crude agreement, Gwet AC1/2 statistics, and Cohen's Kappa were used to estimate inter-rater agreement for confidence and intensity; for frequency, the intra-class correlation coefficient (ICC) was used. The majority of job–agent combinations were evaluated by the two experts to be not exposed (crude agreement >98% of decisions). The degree of agreement between the experts for the confidence of exposure status was Gwet AC1/2 = 0.99 (95% CI: 0.99–0.99), and for intensity, a Gwet AC2 = 0.99 (95% CI: 0.99–0.99). For frequency, an ICC of 0.31 (95% CI: 0.26–0.35) was found. A sub-analysis restricted to job–agent combinations for which the two experts agreed on exposure status revealed a moderate agreement for confidence of exposure (Gwet AC2 = 0.66) and high agreement for intensity (Gwet AC2 = 0.96). For frequency, the ICC was 0.52 (95% CI: 0.47–0.57). A high level of inter-rater agreement was found for identifying exposures and for coding intensity, but agreement was lower for the coding of frequency of exposure. [ABSTRACT FROM AUTHOR]

The effect of complex additives based on cobalt, iron, and manganese oxides and sodium silicate on the phase composition, microstructure, mechanical properties, and sintering of tetragonal zirconia ceramics stabilized with 3 mol % yttria and containing 10 wt % alumina (3Y–TZP–10Al2O3) was studied. The introduction of complex additives significantly affected sintering of the ceramics: the open porosity was less than 1% after annealing at 1250°C. The use of Na2Si2O5–0.33% Mn as a sintering additive provided the minimum of porosity for sintering temperature of 1300°C. Ceramics with flexural strength of 500 ± 16 MPa and the microhardness of 10 GPa was obtained. [ABSTRACT FROM AUTHOR]

The presence of periodontal diseases (PDs) often strongly correlates with other severe chronic inflammatory conditions, including cardiovascular disease, diabetes, and arthritis. However, the mechanisms through which these diseases interact are unclear. In PD, tissue and bone destruction in the mouth is driven by elevated recruitment of polymorphonuclear neutrophils (PMNs), which are primed and recruited from the circulation to sites of inflammation. We predicted that systemic effects on PMN mobilization or priming could account for the interaction between PD and other inflammatory conditions. We tested this using a mouse model of ligature-induced PD and found elevated PMN counts specifically in bone marrow, supporting a systemic effect of periodontal tissue inflammation on PMN production. In contrast, mice with induced peritonitis had elevated PMN counts in the blood, peritoneum, and colon. These elevated counts were further significantly increased when acute peritonitis was induced after ligature-induced PD in mice, revealing a synergistic effect of multiple inflammatory events on PMN levels. Flow cytometric analysis of CD marker expression revealed enhanced priming of PMNs from mice with both PD and peritonitis compared to mice with peritonitis alone. Thus, systemic factors associated with PD produce hyperinflammatory PMN responses during a secondary infection. To analyze this systemic effect in humans, we induced gingival inflammation in volunteers and also found significantly increased activation of blood PMNs in response to ex vivo stimulation, which reverted to normal following resolution of gingivitis. Together, these results demonstrate that periodontal tissue inflammation has systemic effects that predispose toward an exacerbated innate immune response. This indicates that peripheral PMNs can respond synergistically to simultaneous and remote inflammatory triggers and therefore contribute to the interaction between PD and other inflammatory conditions. This suggests larger implications of PD beyond oral health and reveals potential new approaches for treating systemic inflammatory diseases that interact with PD. [ABSTRACT FROM AUTHOR]

An overview of the results in the field of creating bone cements based on calcium and magnesium phosphates with antimicrobial properties intended to replace bone tissue defects is presented. It was noted that the modification of cements based on calcium phosphates with magnesium made it possible to provide high strength, optimal setting time, absence of cytotoxicity, and increased matrix properties of the surface. The problems associated with the use of antibiotics in cement-based systems for their targeted prolonged delivery as bactericidal agents are discussed. Alternative approaches based on the doping of cements with elements exhibiting antimicrobial activity, which makes it possible to avoid the emergence of bactericidal agents, are considered. [ABSTRACT FROM AUTHOR]

The sintering conditions, microstructure, and phase composition of zirconia-based ceramics containing an additive of 0.2 wt % alumina have been studied. It has been shown that the introduction of sodium disilicate as a low-melting additive promotes a decrease in the sintering temperature of zirconia ceramics to 1080‒1180°C. The materials obtained were characterized by a high content of the tetragonal phase and a fine-crystalline structure with a grain size from 40‒50 to 80‒100 nm. It has been shown that the use of sodium disilicate based additives promotes liquid-phase sintering and formation of the dense structure at 1080°C. [ABSTRACT FROM AUTHOR]

Radiation-induced impurity nitrogen centers () in nanosized powders of synthetic hydroxyapatite are studied by pulse EPR and pulse double-frequency EPR, which is named the NMR detected by electron–electron double resonance (ELDOR detected NMR, EDNMR) method. The EPR signals caused by the interaction of the electron of with the environmental nuclei (1H, 14N, and 31P) are identified, and the parameters of the hyperfine and quadrupole interactions of the electron with the 14N nuclei are determined. The possibility of using the EDNMR method in the X-band of microwave frequencies (νmw ≈ 9 GHz) at room temperature to obtain a detailed information about peculiarities of electron-nuclear interactions in hydroxyapatite is demonstrated. [ABSTRACT FROM AUTHOR]

The effect of the introduction of Co2+ to ZrO2–10 wt % Al2O3 ceramic materials on their phase composition, porosity, microstructure, strength, microhardness, cytotoxicity, and cytocompatibility was studied. It was shown that the addition of Co2+ stabilizes the tetragonal form of ZrO2, which is the only form in sintering at 1400°С. An increase in the sintering temperature leads to the formation of the monoclinic form of ZrO2 and subsequent increase in its amount. Densely sintered ceramic materials were obtained, which had a strength of more than 860 MPa, a microhardness of up to 11 GPa, and the composition ZrO2–10 wt % Al2O3–3.8 mol % CoO (3 mol % of the introduced Co2+ cation). In vitro tests demonstrated that the materials are cytocompatible. The introduction of cobalt ions to ZrO2–10 wt % Al2O3 ceramics improves the matrix (for cells) properties. [ABSTRACT FROM AUTHOR]

We have synthesized powders and produced ceramic materials in the tricalcium phosphate–trimagnesium phosphate system with a degree of Mg2+ substitution for Ca2+ up to 40 wt %. It has been shown that increasing the percentage of magnesium in the materials reduces their sintering temperature from 1300 to 1100°C. We have determined the phase composition of the materials and examined their microstructure. The results demonstrate that the addition of Mg2+ ions reduces the precipitation of Ca2+ ions from the ceramics to model fluids and leads to a considerable increase in their three-point bend strength: to 95–120 MPa. [ABSTRACT FROM AUTHOR]

Purpose: To provide empirical evidence on learning barriers and facilitators in instructional science and engineering laboratory settings from a national survey on students with physical disabilities (SwD-P). Methods: A nationwide self-report survey, the Full Participation Science and Engineering Accessibility (FPSEA), was disseminated online via Qualtrics. Approximately 1200 organizations and universities across the United States were contacted through purposive sampling. Descriptive statistics were primarily used for the analysis of the results. Results: Survey findings reveal that students experience a wide range of limitations to full participation in the laboratory, from entering the laboratory (25%) to being given passive roles (50%). Additionally, while 66% of respondents indicated that instructors were willing to help SwD-P participate in science and engineering (S&E) laboratories, 16.8% were not willing to do so, and 47% SwD-P felt that practices were not in place to provide accommodations. The survey also reveals a range of facilitators such as elevators, ramps, accessible course materials and peer assistance. Most respondents (74%) also indicated that peers were helpful in completing laboratory tasks. Conclusion: This survey provides empirical evidence that was previously voiced through non-empirical information in the literature. Participants cited barriers such as inappropriate accommodations and instructors' negative viewpoints, as well as gaining access to facilities even after the enactment of the Americans with Disabilities Act (ADA). These findings suggest that while ADA has lessened some barriers to SwD-P, barriers remain in using the laboratory space. The FPSEA survey fills the gap in finding barriers and facilitators to using S&E laboratories from the SwD-P's perspective. Barriers students with disabilities encounter in science and engineering (S&E) laboratory environments remain unclear. The FPSEA survey fills the gap in finding barriers and facilitators to using S&E laboratories from the SwD-P's perspective. The FPSEA survey allows former and current SwD-P to share their experiences using a postsecondary S&E instructional laboratory. [ABSTRACT FROM AUTHOR]

We have prepared powders and ceramic composite materials in the ZrO2–Al2O3 system containing 10 and 20 wt % Al2O3 and examined the effect of ferric oxide additions on the linear shrinkage, phase composition, porosity, microstructure, and mechanical properties of the ZrO2–Al2O3 ceramic materials. The results demonstrate that the addition of ferric oxide leads to a considerable increase in linear shrinkage and ensures porosity as low as under 1% even at a sintering temperature of 1450°C in both composite materials. Moreover, small amounts of the additive stabilize the tetragonal phase of ZrO2, whereas increasing the Fe content to 3 mol % leads to an increase in the amount of the monoclinic phase. We have obtained densely sintered ZrO2–10% Al2O3 and ZrO2–20% Al2O3 ceramic materials at 1450°C, with a bending strength of up to 760 and 475 MPa, respectively. [ABSTRACT FROM AUTHOR]

A wide range of compositions of zirconia-based composites containing 0, 5, 10, 20 wt % alumina was studied. The dependences of the formation of microstructure and phase composition on the sintering temperature were established. It was shown that the introduction of additives forming low-temperature melts based on sodium silicates, Na2SiO3 and Na2Si2O5, led to a decrease in sintering temperature by 150–200°C. As a result, dense nanocrystalline materials with a crystal size of 50–200 nm, strength of up to 500 MPa, and sintering temperature of 1300–1400°C were obtained. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to address the development of the Full Participation Science and Engineering Accessibility (FPSEA) self-report survey that gathers experiences from students with physical disabilities (SwD-P) using a postsecondary laboratory and to evaluate the survey's stability. Methods: Survey items were generated from an extensive literature review and recommendations articulated by experts. Think-aloud sessions and content validity index (CVI) were used to determine survey content validity and help finalize survey items. Individuals with physical disabilities (n = 20) who have taken a postsecondary science or engineering laboratory course completed the survey and took it again 10–14 days apart. The test–retest reliability was assessed using Spearman Rho coefficients for Likert-scale items, Chi-square and Fisher's exact test for the dichotomous items. Missing data completely at random (MCAR) test was computed before reliability data analysis. Results: Each sub-item passed the MCAR test, indicating that the data are missing completely at random and can be imputed to perform the analysis. Reliability analysis was completed on 20 individuals. The FPSEA had good content reliability: the item-level CVI of items kept ranged from 0.86 to 1. The scale-level CVI was 0.94. Stability was demonstrated with adequate Spearman correlation ranged from 0.56 to 0.86. Conclusions: No previous survey had been developed linking SwD-P and the postsecondary science and engineering (S&E) laboratory setting prior to this work. Overall, FPSEA is reliable and stable for reporting the barriers and facilitators to use S&E laboratories from the SwD-P's perspective. The barriers students with disabilities encounter in S&E laboratory environments are largely unknown. The FPSEA survey may help identify barriers and facilitators to using S&E laboratories for SwD-P. The FPSEA Survey allows former and current SwD-P to share their experiences using a postsecondary S&E instructional laboratory. [ABSTRACT FROM AUTHOR]

We have studied the effect of doping with lithium cations on the phase composition, lattice parameters, and crystallite size of hydroxyapatite at different heat treatment temperatures (900, 1200, and 1400°C). The results demonstrate that, at high degrees of substitution (20 mol %) and heat treatment temperatures of 1200 and 1400°C, lithium cations contribute to conversion of apatite into lithium-substituted tricalcium phosphate. At degrees of substitution of 1, 5, and 10 mol %, the addition of lithium causes no destabilization of the apatite structure even at a temperature of 1400°C. [ABSTRACT FROM AUTHOR]

The sintering, microstructure, and phase composition of the eutectic ceramics of the ZrO2–Al2O3–SiO2 system with an MnO additive have been studied. It has been shown that the additive contributes to the decrease in the sintering temperature to 1250–1350°С. The synthesized materials have a high content of the tetragonal phase, a fine crystalline structure with a grain size of 100–600 nm, and high flexural strength up to 420 MPa. The developed low-temperature materials can find application in mechanical engineering as high-temperature machine parts and refractory materials. [ABSTRACT FROM AUTHOR]

Objectives: To assess the relationship between changes of frailty status and intervening hospitalizations, using information of the GAZEL cohort, matched with the data of the French National Health Data System. Design: Observational cohort study. Participants: Community-dwelling adults of the GAZEL cohort (n = 12145; aged between 58 and 73 years in 2012). Measurements: Frailty was determined with the Strawbridge questionnaire in 2012, 2013 and 2014. Data regarding hospitalizations (notably their number, length of stay, emergency department use, and main diagnosis) were collected from the French National Health Data System. The relationship between intervening hospitalizations and changes of frailty status over time was assessed with multivariate Markov models. Results: The prevalence of frailty was 14% in 2012 and 2013 and 17% in 2014. A total of 2715 changes in frailty status were observed from 2012 to 2014. At least one hospitalization was recorded for 1453 people (12%) between the 2012 and 2013 questionnaires, and 1472 (13%) between the 2013 and 2014 questionnaires. No association was found between intervening hospitalizations and changes of frailty status (aHR 1.14 [0.97–1.35] for robust to frail transition and aHR 0.89 [0.73–1.08] for frail to robust transition). However, repeated hospitalizations, hospitalizations after emergency department use, surgery and several diagnosis groups were significantly associated with transitions towards frailty or its recovery. Conclusion: Hospitalizations encompass a wide range of clinical situations, some of them being associated with incident frailty. An early recognition of these situations could help to better prevent and manage frailty in the early old age. [ABSTRACT FROM AUTHOR]

Background and purpose: Neuropsychological testing plays a key role in various clinical contexts. Even though a substantial number of adults suffer neurological disorders such as early‐onset dementia, stroke, traumatic brain injury or multiple sclerosis, most normative data do not include persons below 65. The aim of this study was to produce updated norms for the Mini‐Mental State Examination, the Free and Cued Selective Reminding Test, the Trail Making Test, verbal fluency tasks and the Digit Symbol Substitution Test for middle‐aged and older adults. Methods: The sample consisted of 51 879 participants aged 45–70 years from the CONSTANCES study. Norms are presented in percentiles stratified on age, education and gender. Results: The results illustrated the effect of age in all tests considered. For tests involving speed processing, the impact of age was observed including in tight age range categories (5 years). The results also showed the well‐known effect of education and an effect of gender in tests involving verbal memory and speed processing. Conclusions: The norms provided allow the variability of the cognitive performances of middle‐aged to older populations to be understood, with a high precision in age categories. The tests considered are broadly used in neuropsychological practice and should be helpful in a variety of clinical contexts. [ABSTRACT FROM AUTHOR]

Calcium sulfate-based powders with magnesium substituting for calcium cations in amounts of 10, 20, and 40 mol % were synthesized by the mechanochemical method. The phase composition of the products, the solubility, and the compressive strength of the obtained cement materials mixed with water were studied. It was shown that the solubility in the physiological saline increases, while the strength of set cements decreases with increasing degree of substitution. The materials are applicable for bone grafting in surgery, for fabrication of composite biomaterials, and as carriers for targeted drug delivery in the human body. [ABSTRACT FROM AUTHOR]

Abstract: Composite materials based on α-tricalcium phosphate and reinforced with calcium sulfate dihydrate (gypsum) granules were studied. In these materials, pores can form in vivo in the medium of the human body because of selective gypsum dissolution. Such materials can be promising for cell technologies of bone tissue regeneration. Such characteristics of the composite materials as phase composition, setting time, compressive strength, and kinetics of dissolution were investigated, depending on content and size of granules. The materials with the setting time and strength suitable for surgery applications were obtained. [ABSTRACT FROM AUTHOR]

Abstract: Based on tricalcium phosphate, new high-strength composite materials were synthesized, in which the strengthening phase was ZrO2. To reduce the sintering temperature and obtain a fine crystalline structure, a special additive based on sodium silicate was developed, which favored the formation of low-temperature melts. It was studied how the ratio between the initial components and the sintering conditions affect the phase composition, microstructure, and mechanical properties of the obtained composite materials. By improving technology and optimizing composition, strong ZrO2-rich composites were produced in the tetragonal modification with a low sintering temperature of 1250-1350°C and a flexural strength to 260 MPa. The composites had microstructure with tricalcium phosphate and ZrO2 crystal sizes to 500 nm and to 5 μm, respectively. Such materials can be used in medicine for manufacturing bone implants capable of withstanding physiological loads. [ABSTRACT FROM AUTHOR]

Abstract: The review of results obtained by the authors in the design of bioresorbable calcium phosphate ceramic materials intended for bond tissue defect regeneration is presented. The development of composite materials and new data in the fabrication of octacalcium phosphate bioresorbable ceramic are elucidated as well. [ABSTRACT FROM AUTHOR]

Interaction of polyimide and two simple organic polymers with an evaporated chromium metal overlayer was studied by surface-sensitive carbon 1s near-edge x-ray absorption fine structure (NEXAFS) spectroscopy. The technique was used to measure unoccupied electronic states in the polymers. Assignments of C1s→π* transitions in poly(pyromellitimido oxydianiline) (PMDA-ODA polyimide) were based upon transitions measured for model polymers which contained structural subunits of the polyimide. Changes in the NEXAFS spectrum of each polymer were observed after sequential depositions of chromium. Abrupt changes in the carbonyl C1s→π* transition peaks show that the carbonyl groups on these polymers are sites for initial interaction with chromium. No evidence was seen for the formation of Cr–arene complexes on any of the polymer surfaces. [ABSTRACT FROM AUTHOR]

Purpose The focus of our study was to understand the influence of demographics of collegiate football players on virtual reality (VR) cognitive scores over multiple seasons. We collected subject demographic factors and VR cognitive scores obtained at multiple time-points each year for four years. By observing multiple years of football athletes' trends in scores through the seasons, we hope to better understand both how individualized factors and playing a collegiate collision sport affect cognition. Methods VR scores and demographic factors from 122 Division I football players through 2019-2022 seasons were analyzed. The VR is a fully immersive system, with separate modules to evaluate spatial memory, reaction time, and balance. Data collection occurred at pre-season, post-camp, mid-season, and post-season. Results Statistical analyses were conducted using SPSS v25. Participants were categorized by position, psychiatric disorder, concussion history, and year. Paired T-tests and one-way ANOVA were used to compare the scores of participants based on year and demographic factors. No demographic factors reached statistical significance, however VR balance scores were significantly lower in 2021 compared to other seasons (p<.05). Spatial memory scores trended toward significance between individuals with and without concussion history (p=.064). VR balance scores were significantly lower in 2021 (p<.001) across all time points. Conclusions While it was found that demographic factors did not influence VR performance, data suggests influence of concussion history on spatial memory warrants further investigation. The balance deficits in 2021 merit further exploration, but overall findings suggest participation in collegiate football without observable acute cognitive deficit. [ABSTRACT FROM AUTHOR]

Summary: Background: The prevalence of sesame food allergy (SFA) has increased over recent years, with the potential of anaphylactic reactions upon exposure. Oral food challenge (OFC) remains the diagnostic standard, yet its implementation may be risky. Commercial skin prick tests (SPT) have a low sensitivity. Investigation of alternate diagnostic methods is warranted. Objective: To evaluate the utility of SPT and the basophil activation test (BAT) for SFA diagnosis. Methods: Eighty‐two patients with suspected SFA completed an open OFC to sesame or reported a recent confirmed reaction. Patients were administered skin prick tests (SPT) with commercial sesame seed extract (CSSE) and a high protein concentration sesame extract (HPSE) (100 mg/mL protein). Whole blood from 80 patients was stimulated with sesame seed extract (40‐10 000 ng/mL protein) for BAT), assessing CD63 and CD203c as activation markers. Results: Sixty patients (73%) had IgE‐mediated reactions to sesame, and 22 (27%) did not react. Receiver operating characteristic (ROC) curve analysis demonstrated an area under the curve (AUC) of 0.87 for HPSE‐SPT and 0.66 for CSSE‐SPT. At 1000 ng/mL of sesame protein, induction of CD63 and CD203c was weakly but significantly associated with OFC eliciting dose by rank (Spearman's rho = −.42 (P < .01) and −.35 (P < .05) for CD63 and CD203c, respectively). By ROC analysis, the AUC was 0.86 for CD63 and was 0.81 for CD203c sesame‐induced basophil expression. Using HPSE‐SPT as a first test to definitively diagnose (n = 24) or rule‐out (n = 5) SFA and BAT as a second test to diagnose the remainder results in the correct classification of 73 of 80 (91%) patients, leaving one false negative and 4 false positive patients. Two BAT non‐responders remain unclassified by this algorithm. Conclusions & Clinical Relevance: While prospective cohort validation is necessary, joint utilization of BAT and SPT with HPSE extract may obviate the need for OFC in most SFA patients. [ABSTRACT FROM AUTHOR]

The influence of lithium substitution for calcium over a broad concentration range (0-20 mol %) on the crystal lattice parameters, coherent scattering regions, and phase composition was studied for hydroxyapatite synthesized by precipitation from solutions and heat treatment at 900, 1200, and 1400°C. The lithium substitution in a more than 10 mol % concentration and increase in the heat treatment temperature to 1400°C give rise to a complex phase composition, which includes not only the apatite phase, but also two tricalcium phosphate phases and calcium pyrophosphate. The results are useful for the development of hydroxyapatite-based materials for bone surgery. [ABSTRACT FROM AUTHOR]

Abstract: Background: Ambiguities exist regarding the diagnosis of tree‐nut allergy, necessitating either their elimination or the performance of oral food challenges (OFCs). Objective: To examine the coincidences of allergies among tree‐nuts and improve diagnostic testing to minimize the need for OFC. Methods: Eighty‐three patients prospectively evaluated for walnut, pecan, cashew, pistachio, hazelnut, and almond allergy. A history of previous reactions was obtained, and standardized skin prick tests (SPTs) using finely ground tree‐nut solution and basophil activation tests (BAT) were performed. Patients underwent OFC for each tree‐nut they eliminated and to which a reaction in the previous 2 years was not documented. Results: While most patients were sensitized to 5‐6 tree‐nuts, over 50% were allergic to only 1‐2 tree‐nuts. The highest rate of allergy in sensitized patients was observed for walnut (74.6%) and cashew (65.6%). The rate of co‐allergy for most tree‐nuts was <30%. Two‐thirds of walnut‐ and cashew‐allergic patients were also allergic to pecan and pistachio, respectively, while all pecan‐ and pistachio‐allergic patients were allergic to walnut and cashew, respectively. Receiver‐operating characteristic analysis for SPT and BAT was tree‐nut dependent and yielded area under the curve (AUC) values ranging from 0.75 to 0.94. Knowledge of coincident allergies in these pairs along with the combination of SPT and BAT correctly distinguished allergic from tolerant patients for walnut (87%), pecan (66%), cashew (71%), and pistachio (79%). Conclusion: The data presented here should assist in differentiating between allergic and tolerant patients, decrease the need for OFC, and allow for appropriate elimination recommendations. [ABSTRACT FROM AUTHOR]

Background Quality of life ( QOL) is impaired in patients with food allergy and improves following oral immunotherapy ( OIT). However, the treatment itself is prolonged and demanding. We examined changes in patient QOL during OIT for food allergy. Methods The FAQLQ- PF was administered to children aged 4-12 years undergoing OIT for milk, peanut, or egg allergy, at the beginning and after 4 months of treatment. Patients were categorized as improved, unchanged, or diminished FAQLQ- PF (>0.5 point decrease, a change of ≤0.5 points, or >0.5 increase, respectively) and compared. Food-allergic patients not undergoing OIT served as controls. Results The Food Anxiety, Social and Dietary Limitation, and total FAQLQ- PF scores improved significantly during the study period ( P=.001, P=.018, and P=.01, respectively) in treated but not in control patients, while the Emotional Impact did not. The change in the FAQLQ- PF was independent of the maximal tolerated dose at baseline or following four months of treatment, the pace of dose increase, or the number or severity of reactions experienced. The total FAQLQ- PF score was inversely associated with the score at baseline on multivariate analysis (regression coefficient=−0.56, P<.001). That was driven primarily by improvement in QOL scores in patients with high score (worse QOL) at baseline. Some patients with low FAQLQ- PF score (better QOL) at baseline deteriorated. Conclusions QOL of patients with food allergy improves in some but deteriorates in others during OIT. Patients with impaired QOL at baseline improve significantly despite the treatment burden. Some patients with better QOL at baseline might deteriorate during OIT. [ABSTRACT FROM AUTHOR]

The effect of Ti and Zr substitutions for Ca cations on the formation of tricalcium phosphate and hydroxyapatite has been studied in a wide concentration range: from 0.1 to 20 mol %. Upon the incorporation of Ti and Zr cations into tricalcium phosphate, the major forming phase is β-tricalcium phosphate. On the addition of low substituent concentrations to hydroxyapatite, we observe the formation of a single-phase material with the apatite structure. Increasing the substituent concentration to 10-20 mol % Ti or 20 mol % Zr leads to the formation of tricalcium phosphate. The unit-cell volume of the cation-substituted tricalcium phosphates has been shown to decrease with increasing substituent concentration. In the zirconium-containing hydroxyapatites, the unit-cell volume decreases with increasing zirconium concentration, whereas the titanium-containing hydroxyapatites exhibit an opposite tendency. [ABSTRACT FROM AUTHOR]

We have studied the influence of the cement liquid composition and the relationship between the components of the calcium sulfate-precipitated calcium phosphate system in a wide concentration range on the setting time, phase composition, microstructure, and mechanical properties of cement materials. The results demonstrate that the greatest promise is held by a magnesium phosphate-based cement liquid which, when mixed with powder, forms a high-strength phase, leading to a considerable increase in the strength of the cements. The addition of 20 wt % calcium sulfate to the starting mixture ensures dispersion hardening of the cements. We have obtained new cement materials offering a strength of up to 60 MPa, which are expected to find medical applications. [ABSTRACT FROM AUTHOR]

We have studied the influence of the sintering temperature, AlO additions, and liquid-forming sintering aids on the phase composition and microstructure of fluorohydroxyapatite-based composite ceramic materials containing 20 and 60% zirconia. The addition of alumina has been shown to prevent secondary recrystallization processes during sintering and contribute to stabilization of tetragonal zirconia. The addition of the sintering aid has made it possible to lower the sintering temperature to 1200°C. [ABSTRACT FROM AUTHOR]

Objectives: Occupational exposure to disinfectants is associated with work-related asthma, especially in healthcare workers. However, little is known about the specific products involved. To evaluate disinfectant exposures, we designed job-exposure (JEM) and job-task-exposure (JTEM) matrices, which are thought to be less prone to differential misclassification bias than self-reported exposure. We then compared the three assessment methods: self-reported exposure, JEM and JTEM.Methods: Disinfectant use was assessed by an occupational questionnaire in 9073 US female registered nurses without asthma, aged 49-68 years, drawn from the Nurses' Health Study II. A JEM was created based on self-reported frequency of use (1-3, 4-7 days/week) of 7 disinfectants and sprays in 8 nursing jobs. We then created a JTEM combining jobs and disinfection tasks to further reduce misclassification. Exposure was evaluated in 3 classes (low, medium, high) using product-specific cut-offs (eg, <30%, 30-49.9%, ≥50%, respectively, for alcohol); the cut-offs were defined from the distribution of self-reported exposure per job/task.Results: The most frequently reported disinfectants were alcohol (weekly use: 39%), bleach (22%) and sprays (20%). More nurses were classified as highly exposed by JTEM (alcohol 41%, sprays 41%, bleach 34%) than by JEM (21%, 30%, 26%, respectively). Agreement between JEM and JTEM was fair-to-moderate (κ 0.3-0.5) for most disinfectants. JEM and JTEM exposure estimates were heterogeneous in most nursing jobs, except in emergency room and education/administration.Conclusions: The JTEM may provide more accurate estimates than the JEM, especially for nursing jobs with heterogeneous tasks. Use of the JTEM is likely to reduce exposure misclassification. [ABSTRACT FROM AUTHOR]

Effect of ripening in the mother liquor on the degree of crystallinity and dispersity of mixed powders of calcium and magnesium phosphates is studied as a function of magnesium content with the elemental composition such that (Ca + Mg)/P = 2. Ripening is found to have a positive effect on crystallinity of the apatite phase of powders. Nanocrystals with lowered tendency to aggregation are formed during the ripening period, which affords the powders with specific surface area as high as 80 m/g. The morphology of the constituent particles depends on the magnesium content. Crystallization processes are essentially completed by the 21st day of ripening. [ABSTRACT FROM AUTHOR]

Background and purpose The aim of our study was to examine the effect sizes of different cognitive function determinants in middle and early old age. Methods Cognitive functions were assessed in 11 711 volunteers (45 to 75 years old), included in the French CONSTANCES cohort between January 2012 and May 2014, using the free and cued selective reminding test ( FCSRT), verbal fluency tasks , digit-symbol substitution test ( DSST) and trail making test ( TMT) , parts A and B. The effect sizes of socio-demographic (age, sex, education), lifestyle (alcohol, tobacco, physical activity), cardiovascular (diabetes, blood pressure) and psychological (depressive symptomatology) variables were computed as omega-squared coefficients ( ω2; part of the variation of a neuropsychological score that is independently explained by a given variable). Results These sets of variables explained from R2 = 10% (semantic fluency) to R2 = 26% ( DSST) of the total variance. In all tests, socio-demographic variables accounted for the greatest part of the explained variance. Age explained from ω2 = 0.5% (semantic fluency) to ω2 = 7.5% ( DSST) of the total score variance, gender from ω2 = 5.2% ( FCSRT) to a negligible part (semantic fluency or TMT) and education from ω2 = 7.2% ( DSST) to ω2 = 1.4% ( TMT-A). Behavioral, cardiovascular and psychological variables only slightly influenced the cognitive test results (all ω2 < 0.8%, most ω2 < 0.1%). Conclusion Socio-demographic variables (age, gender and education) are the main variables associated with cognitive performance variations between 45 and 75 years of age in the general population. [ABSTRACT FROM AUTHOR]

We have studied the effect of heat treatment in a wide temperature range (from 300 to 1500°C) on the phase composition, heat effects and weight loss of powder materials in a system of calcium phosphates and magnesium phosphates with (Ca + Mg)/P = 2. The results demonstrate that crystalline magnesium-substituted whitlockite phases begin to form at temperatures above 600°C. Raising the heat treatment temperature reduces the degree of magnesium substitution for calcium in the structure of the magnesium-substituted whitlockite. Tetracalcium phosphate, a high-temperature phase, is formed through apatite phase recrystallization. [ABSTRACT FROM AUTHOR]

We have studied the influence of the sintering temperature and modifying additives on the phase composition, microstructure, and mechanical strength of a fluorohydroxyapatite-based composite ceramic material containing 20 wt % zirconia. The addition of 5 wt % alumina has been shown to prevent recrystallization processes and contribute to phase composition stabilization. Moreover, the addition of a sintering aid (2 wt %) has made it possible to lower the sintering temperature to 1200°C and raise the bending strength of the material to 143 MPa. [ABSTRACT FROM AUTHOR]

The sintering, microstructure, and phase composition of zirconia ceramics containing a sodium niobate addition have been studied. It has been shown that the addition leads to a decrease in the sintering temperature to 1400°С. The resulting materials are characterized by a high content of the tetragonal phase, a fine-crystalline structure, and a high flexural strength up to 440 MPa. The developed low-temperature materials can be used in dentistry as ceramic crowns. [ABSTRACT FROM AUTHOR]

Amelogenin gene organization varies from 6 exons (1,2,3,5,6,7) in amphibians and sauropsids to 10 in rodents. The additional exons are exons 4, 8, 9, and "4b", the latter being as yet unidentified in AMELX transcripts. To learn more about the evolutionary origin of these exons, we used an in silico approach to find them in 39 tetrapod genomes. AMEL organization with 6 exons was the ancestral condition. Exon 4 was created in an ancestral therian (marsupials + placentals), then exon 9 in an ancestral placental, and finally exons "4b" and 8 in rodents, after divergence of the squirrel lineage. These exons were either inactivated in some lineages or remained functional: Exon 4 is functional from artiodactyls onward; exon 9 is known, to date, only in rodents, but could be coding in various mammals; and exon "4b" was probably coding in some rodents. We performed PCR of cDNA isolated from mouse and human tooth buds to identify the presence of these transcripts. A sequence analogous to exon "4b", and to exon 9, could not be amplified from the respective tooth cDNA, indicating that even though sequences similar to these exons are present, they are not transcribed in these species. [ABSTRACT FROM AUTHOR]