Microwave pyrolysis of polypropylene, and high-density polyethylene, and catalytic gasification of waste coffee pods to hydrogen-rich gas.

Plastic waste poses a critical environmental challenge for the world. The proliferation of waste plastic coffee pods exacerbates this issue. Traditional disposal methods such as incineration and landfills are environmentally unfriendly, necessitating the exploration of alternative management strategies. One promising avenue is the pyrolysis in-line reforming process, which converts plastic waste into hydrogen. However, traditional pyrolysis methods are costly due to inefficiencies and heat losses. To address this, for the first time, our study investigates the use of microwave to enhance the pyrolysis process. We explored microwave pyrolysis for polypropylene (PP), high-density polypropylene (HDPE), and waste coffee pods, with the latter primarily comprising polypropylene. Additionally, catalytic ex-situ pyrolysis of coffee pod pyrolysis over a nickel-based catalyst was investigated to convert the evolved gas into hydrogen. The single-stage microwave pyrolysis results revealed the highest gas yield at 500 °C for HDPE, and 41 % and 58 % (by mass) for waste coffee pods and polypropylene at 700 °C, respectively. Polypropylene exhibited the highest gaseous yield, suggesting its readiness for pyrolytic degradation. Waste coffee pods uniquely produced carbon dioxide and carbon monoxide gases because of the oxygen present in their structure. Catalytic reforming of evolved gas from waste coffee pods using a 5 % nickel loaded activated carbon catalyst, yielded 76 % (by volume) hydrogen at 900 °C. These observed results were supported by elemental balance analysis. These findings highlight that two-stage microwave and catalysis assisted pyrolysis could be a promising method for the efficient management of waste coffee pods, particularly for producing clean energy.

Insights into acrylamide and furanic compounds in coffee with a focus on roasting methods and additives.

Roasting is necessary for bringing out the aroma and flavor of coffee beans, making coffee one of the most consumed beverages. However, this process also generates a series of toxic compounds, including acrylamide and furanic compounds (5-hydroxymethylfurfural, furan, 2-methylfuran, 3-methylfuran, 2,3-dimethylfuran, and 2,5-dimethylfuran). Furthermore, not much is known about the formation of these compounds in emerging coffee formulations containing alcohol and sugars. Therefore, this study investigated the effect of roasting time and degree on levels of acrylamide and furanic compounds in arabica coffee using fast and slow roasting methods. The fast and slow roasting methods took 5.62 min and 9.65 min, respectively, and reached a maximum of 210 °C to achieve a light roast. For the very dark roast, the coffee beans were roasted for 10.5 min and the maximum temperature reached 245 °C. Our findings showed that the levels of acrylamide (375 ± 2.52 µg kg-1) and 5-HMF (194 ± 11.7 mg kg-1) in the slow-roasted coffee were 35.0 % and 17.4 % lower than in fast-roasted coffee. Furthermore, light roast coffee had significantly lower concentrations of acrylamide and 5-HMF than very dark roast, with values of 93.7 ± 7.51 µg kg-1 and 21.3 ± 10.3 mg kg-1, respectively. However, the levels of furan and alkylfurans increased with increasing roasting time and degree. In this study, we also examined the concentrations of these pollutants in new coffee formulations consisting of alcohol-, sugar-, and honey-infused coffee beans. Formulations with honey and sugar resulted in higher concentrations of 5-HMF, but no clear trend was observed for acrylamide. On the other hand, formulations with honey had higher concentrations of furan and alkylfurans. These results indicate that optimizing roasting time and temperature might not achieve the simultaneous reduction of all the pollutants. Additionally, sugar- and honey-infused coffee beans are bound to have higher furanic compounds, posing a higher health risk.

Organic arabic coffee husk: Antioxidant and cytoprotective properties and potential impacts on selected human intestinal bacterial populations of individuals with diabetes.

Coffee husks are the main by-product of the coffee industry and have been traditionally discarded in the environment or used as fertilizers. However, recent studies have shown that coffee husks have bioactive compounds, such as phenolics and fiber-bound macro antioxidants, offering a range of potential health benefits. This study evaluated the antioxidant capacity, cytoprotective/cytotoxic properties, and stimulatory effects on the relative abundance of selected intestinal bacterial populations of individuals with diabetes of organic coffee husks. Organic coffee husk had good antioxidant capacity, maintained under simulated gastric conditions, with more than 50% of antioxidant capacity remaining. Organic coffee husk exerted cytoprotective properties in Caco-2 cells, indicating that cellular functions were not disturbed, besides not inducing oxidation. Overall, organic coffee husk promoted positive effects on the abundance of distinct intestinal bacterial groups of individuals with diabetes during in vitro colonic fermentation, with a higher relative abundance of Bifidobacterium spp., indicating the availability of components able to reach the colon to be fermented by intestinal microbiota. Organic coffee husk could be a circular material to develop new safe and pesticide-free functional ingredients with antioxidant and potential beneficial effects on human intestinal microbiota.

Decoding coffee cardiometabolic potential: Chemical composition, nutritional, and health relationships.

Coffee is one of the most consumed beverages worldwide, recognized for its unique taste and aroma and for its social and health impacts. Coffee contains a plethora of nutritional and bioactive components, whose content can vary depending on their origin, processing, and extraction methods. Gathered evidence in literature shows that the regular coffee consumption containing functional compounds (e.g., polysaccharides, phenolic compounds, and melanoidins) can have potential beneficial effects on cardiometabolic risk factors such as abdominal adiposity, hyperglycemia, and lipogenesis. On the other hand, coffee compounds, such as caffeine, diterpenes, and advanced glycation end products, may be considered a risk for cardiometabolic health. The present comprehensive review provides up-to-date knowledge on the structure-function relationships between different chemical compounds present in coffee, one of the most prevalent beverages present in human diet, and cardiometabolic health.

Surface roughness of different types of resin composites after artificial aging procedures: an in vitro study.

BACKGROUND: The temperature changes, chemical agents, and brushing activity that resin composite restorations are exposed to in the oral environment can cause changes in surface roughness. In this study, the aim was to investigate in vitro the clinical one-year surface roughness changes of different types of composites (flowable or conventional) from the same companies by subjecting them to immersion in solutions, brushing, and thermal cycling procedures to simulate intraoral conditions. METHODS: Four different resin composite brands were included in the study using both their conventional (Charisma Smart, 3M Filtek Ultimate Universal, Omnichroma, Beautifil II) and flowable resin composites (Charisma Flow, 3M Filtek Ultimate Flowable, Omnichroma Flow, Beautifil Flow Plus F00), giving 4 groups with 2 types of resin composite in each. 40 samples were prepared for each group/resin type, for a total of 320 samples. After initial surface roughness measurements by a mechanical profilometer, the samples were divided into 4 subgroups (n = 10) and immersed in solutions (distilled water, tea, coffee, or wine) for 12 days. The samples were then subjected to 10,000 cycles of brushing simulation and 10,000 cycles of thermal aging. Surface roughness measurements were repeated after the procedures. For statistical analysis, the 3-way analysis of variance and the Tukey test were used (p < 0.05). RESULTS: It was concluded that composite groups and types had an effect on surface roughness at time t0 (p < 0.001). At time t1, the highest surface roughness value was obtained in the Beautifil-conventional interaction. When the surface roughness values between time t0 and t1 were compared, an increase was observed in the Beautifil II and Beautifil Flow Plus F00, while a decrease was observed in the other composite groups. CONCLUSION: Composite groups, types, and solutions had an effect on the surface roughness of resin composites. After aging procedures, it was concluded that the Beautifil group could not maintain the surface structure as it exceeded the threshold value of 0.2 µm for bacterial adhesion.

Sensory analysis of the flavor profile of full immersion hot, room temperature, and cold brewed coffee over time.

With the growing popularity of cold brewed coffee comes a need for brewing efficiency while preserving the desirable flavor profile. Despite the wide use of full immersion brewing techniques, the effect of brew time on the dynamic sensory profiles of full immersion brewed coffee remains underexplored. Here, we investigated the relationship between coffee sensory quality and extraction dynamics, measured as Total Dissolved Solids (TDS) and Extraction (E) of full immersion brewed coffee at various roast levels, and brewing temperatures (4 °C, 22 °C and 92 °C), over brew time using a generic descriptive analysis method. Specifically, different brew time points were selected for different temperatures based on five targeted coffee extraction stages. Furthermore, the unique experimental design also explored a sensory-driven engineering research process. Roast level had the greatest impact on the sensory profile of the coffees, followed by brewing temperature, but brew time, especially the longer brew times as TDS plateaued, had subtler impacts than expected. Twenty-five of 28 sensory attributes were significantly different among the 30 coffee samples, indicating a single source green coffee blend can produce a wide range of complex sensory profiles using different combinations of roast level, temperature, and brew time. Specifically, the intensity of sweetness was negatively correlated with TDS, and 19 other attribute intensities were positively correlated with TDS. Interestingly, we found that certain long time cold brews had similar sensory profiles to those of some short time hot brews, suggesting the sensory profiles of certain hot brews and cold brews could possibly be matched through controlled preparation. Overall, our study demonstrated an approach of integrating food engineering and sensory analysis for product development, and our findings provide valuable insights into the extraction dynamics and sensory quality of full immersion brewed coffee and opens new brewing avenues for the coffee industry.

Children of Nature: Thoughts on Targeted and Untargeted Analytical Approaches to Decipher Polyphenol Reactivity in Food Processing and Metabolism.

Following 25 years of polyphenol research in our laboratory, the astonishing chemical and metabolic reactivity of polyphenols resulting in considerable chemical diversity has emerged as the most remarkable attribute of this class of natural products. To illustrate this concept, we will present selected data from black tea and coffee chemistry. In black tea chemistry, enzymatic fermentation converts six catechin derivatives into an estimated 30 000 different polyphenolic compounds via a process we have termed the oxidative cascade process. In coffee roasting, around 45 chlorogenic acids are converted into an estimated 250 novel derivatives following a series of diverse chemical transformations. Following ingestion by humans, these dietary polyphenols, whether genuine secondary metabolites or food processing products, encounter the microorganisms of the gut microbiota, converting them into a myriad of novel structures. In the case of coffee, only two out of 250 chlorogenic acids are absorbed intact, with most others being subject to gut microbial metabolism. Modern mass spectrometry (MS) has been key in unravelling the true complexity of polyphenols subjected to food processing and metabolism. We will accompany this assay with a short overview on analytical strategies developed, including ultrahigh-resolution MS, tandem MS, multivariate statistics, and molecular networking that allow an insight into the fascinating chemical processes surrounding dietary polyphenols. Finally, experimental results studying biological activity of polyphenols will be presented and discussed, highlighting a general promiscuity of this class of compounds associated with nonselective protein binding leading to loss of enzymatic function, another noteworthy general property of many dietary polyphenols frequently overlooked.

Dietary habits as associated factors with irritable bowel syndrome among medical students: evidence from a cross-sectional study.

BACKGROUND: Research on Irritable Bowel Syndrome (IBS) among medical students has increased globally, highlighting a high prevalence in this demographic. However, there is a lack of data specifically regarding the prevalence of IBS among medical students in Yemen. This study aimed to investigate the prevalence and associated factors of IBS among Yemeni medical students. METHODS: We conducted a cross-sectional study involving medical students who completed a validated self-administered questionnaire incorporating socio-demographic information, dietary habits, smoking status, sleep patterns, and the Rome IV criteria for IBS. We used bivariate and multivariate logistic regression models to identify IBS's associated factors, estimated as odds ratios (ORs) with 95% confidence intervals (CIs) and average marginal effect (AME) on the predicted probability of IBS. RESULTS: The study included 351 medical students with a mean age of 22.53 ± 2.70 years; 39.60% (139) were females. The prevalence of IBS was 26.21% (92 students), with 67.39% (62) of them classified as IBS-M (mixed). In multivariable analysis, the consumption of carbonated soft drinks remained significantly associated with IBS (OR: 3.35; 95% CI: 1.14-9.88; P = 0.028). In males, coffee consumption had a substantial effect on the predicted probability of IBS (AME: 11.41%; 95% CI: 0.32-22.60). In females, the consumption of carbonated soft drinks had a significant effect on the predicted probability of IBS (AME: 24.91%; 95% CI: 8.34-41.48). CONCLUSION: The consumption of carbonated soft drinks is significantly associated with IBS among medical students, with a particularly notable increase in the predicted probability of IBS in females. These findings highlight the necessity for gender-specific dietary recommendations in IBS management. Further research is essential to investigate IBS in the general population to gain a comprehensive understanding of its prevalence and associated factors.

Evaluation of the Caffeine Content in Servings of Popular Coffees in Terms of Its Safe Intake-Can We Drink 3-5 Cups of Coffee per Day, as Experts Advise?

The spreading knowledge of the health benefits of coffee and the development of gastronomy with a wide range of coffees prompt an evaluation of their caffeine content in terms of safe intake. The study analyzed the caffeine content of popular coffees in comparison with recommendations for a safe single dose (200 mg) and daily caffeine intake (400 mg), and guidelines for drinking 3-5 cups of coffee per day. A total of 299 coffee samples from franchise shops and homemade coffees were tested. The "takeaway" coffees had a three times higher mean caffeine content (p < 0.005) compared to homemade coffees. Americano coffee was the "strongest" (143 mg caffeine/serving on average), while coffee prepared by pouring hot water over one teaspoon of ground coffee was the "lightest" (23 mg caffeine/serving on average) (p < 0.05). Over 200 mg of caffeine per serving was found in 4% of samples. Over 400 mg of caffeine would be consumed by people drinking "on the go" 4-5 servings of many types of coffee, except espresso. In this respect, homemade coffees are safer. Therefore, recommendations on drinking coffee should be more practical, and indicate not only the number of cups, but also the "strength" of various types of coffee, in order to avoid the regular intake of high amounts of caffeine.

The color stability of artificial white spot lesions treated with resin infiltration after exposure to staining beverages.

BACKGROUND: To evaluate the effect of staining beverages on the color-changing of resin-infiltrated artificial white spot lesions (WSLs). METHODS: Thirty-five artificial WSLs were created by pH cycling on flat bovine teeth specimens. The WSLs were treated with resin infiltration and were divided into five groups based on staining beverages: artificial saliva, coffee, wine, green tea, and Coca-Cola. These specimens were subjected to a 28-day exposure to the respective beverages. Color stability was assessed using a spectrophotometer at different time points: baseline, after 7, 14, 21, and 28 days of exposure, and repolishing. The color difference (∆E) between each time point and the baseline was calculated. Statistical analysis was performed using two-way measures ANOVA with a significance level of p = 0.05. RESULTS: All resin-infiltrated specimens exposed to staining beverages for 7 days exhibited more significant color changes than those exposed to artificial saliva. The color change patterns varied based on the type of beverage. The color alterations intensified with extended immersion in the wine and Coca-Cola groups, while there were no significant differences in the color of specimens after 28 days of immersion in the coffee and green tea groups. However, after cleaning with pumice powder, all specimens showed significantly reduced color changes compared to those observed after 28 days of immersion, except those immersed in coffee. CONCLUSIONS: Exposure of resin-infiltrated bovine tooth specimens to staining beverages resulted in a significant color alteration as the immersion time increased. However, the staining effect could be minimized by cleaning with pumice powder, except for the coffee group. CLINICAL RELEVANCE: After resin infiltration treatment, patients should be advised to minimize the consumption of colored beverages to prevent staining that could impact esthetic appearance.

Exploring accurate mass measurements in pixel-based chemometrics: Advancing coffee classification with GC-HRMS-A proof of concept study.

This paper presents a study that assesses the application of chemometrics for classifying coffee samples in a quality control context. High-resolution and accurate mass measurements were utilized as input for pixel-based orthogonal partial least squares discriminant analysis (OPLS-DA) models. The compositional data were acquired through a fully automated workflow combining headspace solid-phase microextraction and gas chromatography-high-resolution mass spectrometry (GC-HRMS) using an FT-Orbitrap® mass analyzer. A workflow centered on accurate mass measurements was successfully utilized for group-type analysis, offering an alternative to methods relying solely on MS similarity searches. The predictive models underwent thorough evaluation, demonstrating robust multivariate classification performance. Five key coffee attributes, bitterness, acidity, body, intensity, and roasting level were successfully predicted using GC-HRMS data. The results revealed strong predictive accuracy across all models, ranging from 88.9 % (bitterness) to 94.4 % (roasting level). This study represents a significant advancement in automating methods for coffee quality control, notably increasing the predictive ability of the models compared to existing literature.

In vitro human colonic fermentation of coffee arabinogalactan and melanoidin-rich fractions.

Coffee beverage is a source of dietary fiber composed by arabinogalactans, which can also be associated to proteins and phenolic compounds, originating melanoidins. Human colonic in vitro fermentations of coffee fractions, one rich in melanoidins (Mel) and the other in its parental polysaccharide arabinogalactans (AG), were performed in order to evaluate the metabolites produced by microbiota, namely short-chain fatty acids (SCFA), phenolic compounds, and bile acids. After 48 h of fermentation, a higher fermentability of the carbohydrate fraction of AG (62 %) than that of Mel (27 %) was observed, resulting in a SCFA content of 63 mM and 22 mM, respectively. Supplementation with AG and Mel fractions decreased the acetate:propionate ratio from 4.7 (in the absence of coffee fractions) to 2.5 and 3.5, respectively, suggesting a potential inhibition of HMG-CoA reductase, a rate-limiting enzyme for cholesterol synthesis. The fermentation of coffee fractions yielded dihydroferulic and dihydrocaffeic acids, known to have antioxidant properties. In the presence of Mel, it was observed a decrease (from 0.25 to 0.16 mg/mL) in the production of secondary bile acids, whose high content is associated to the development of several diseases, such as colorectal cancer, neurodegenerative and cardiovascular.

Altering Mechanical and Dissolution Properties of Coffee Deposit by Adding Glucose.

Glucose modifies the mechanical stability of coffee films and facilitates their dissolution dynamics at the microscale, rendering glucose-coffee a valuable natural biomaterial system for studying pharmaceutical applications. We show the glucose-dependent inhibition of crack propagation during the evaporation of glucose-coffee droplets. The addition of glucose increases the hardness, stiffness, and shear modulus of films, as measured by surface nanomechanical testing. The glucose-coffee film dissolves faster and more evenly than the pure coffee film through interfaces. The water penetrates through well-dissolved glucose channels. The modified mechanical properties and adjustable dissolution time, coupled with edibility, position the glucose-modified coffee as an excellent candidate for developing pharmaceutical inks for personalized medicine droplet-based printing.

What the Fika? Implementation of Swedish Coffee Breaks During Emergency Medicine Conference.

Introduction: In this study we aimed to investigate the effects of incorporating Swedish-style fika (coffee) breaks into the didactic schedule of emergency medicine residents on their sleepiness levels during didactic sessions. Fika is a Swedish tradition that involves a deliberate decision to take a break during the workday and usually involves pastries and coffee. We used the Karolinska Sleepiness Scale to assess changes in sleepiness levels before and after the implementation of fika breaks. Methods: The study design involved a randomized crossover trial approach, with data collected from emergency medicine residents over a specific period. This approach was done to minimize confounding and to be statistically efficient. Results: Results revealed the average sleepiness scale was 4.6 and 5.5 on fika and control days, respectively (P = 0.004). Conclusion: Integration of fika breaks positively influenced sleepiness levels, thus potentially enhancing the educational experience during residency didactics.

Evaluation of Surface Roughness and Microhardness of Bulk-fill and Nanohybrid Composite after Exposure to Different Beverages at Various Time Intervals - An In vitro Study.

AIM: The aim of the study was to compare the surface roughness and microhardness of bulk-fill composite and nanohybrid composite resin after exposure to three different beverages at different time intervals. METHODOLOGY: In this study, 60 composite discs each for bulk fill and nanohybrid, of dimensions 10 mm × 2 mm were made. Both composites were randomly divided into four subgroups, i.e., 15 samples each for artificial saliva, tea, coffee, and soft drinks which were further subdivided into five samples for three time intervals. Composite resin discs were immersed in beverages for 4 min in 24 h for 7, 15, and 30 days. All samples were evaluated for surface roughness and microhardness before and after immersion. RESULTS: Both the composites showed a significant increase in surface roughness in all the beverages with maximum change in surface roughness observed in nanohybrid composite resin immersed in soft drinks. Furthermore, the microhardness of both the composites was decreased significantly in all beverages with maximum change in microhardness observed in nanohybrid composite resin immersed in soft drinks. CONCLUSIONS: Bulk-fill composite resin has better resistance to surface roughness and higher microhardness as compared to nanohybrid. Furthermore, acidic beverages highly affect the physical properties of both composite resins for longer periods.

Résumé Objectif:Comparer la rugosité de surface et la microdureté du composite Bulk-Fill et de la résine composite nanohybride après exposition à trois boissons différentes à différents intervalles de temps.Matériels et Méthodes:Dans cette étude, 60 disques composites chacun pour remplissage en vrac et nanohybride, de dimensions 10 mm X 2 mm ont été fabriqués. Les deux composites ont été divisés au hasard en quatre sous-groupes, soit 15 échantillons chacun pour la salive artificielle, le thé, le café et les boissons gazeuses, qui ont ensuite été subdivisés en 5 échantillons pendant 3 intervalles de temps. Des disques de résine composite ont été immergés dans des boissons pendant 4 minutes en 24 heures pendant 7, 15 et 30 jours. Tous les échantillons ont été évalués pour la rugosité de surface et la microdureté avant et après immersion.Résultats:Les deux composites ont montré une augmentation significative de la rugosité de surface dans toutes les boissons, un changement maximal de rugosité de surface ayant été observé dans la résine composite nanohybride immergée dans une boisson gazeuse. De plus, la microdureté des deux composites a diminué de manière significative dans toutes les boissons, un changement maximal de microdureté ayant été observé dans la résine composite nanohybride immergée dans une boisson gazeuse.Conclusions:La résine composite de remplissage en vrac a une meilleure résistance à la rugosité de surface et une microdureté plus élevée que la nanohybride. De plus, les boissons acides affectent fortement les propriétés physiques des deux résines composites sur des périodes plus longues.

Lipophilic and Hydrophilic Metabolites as Descriptors of Different Coffee Beverages.

Coffee is a widely consumed beverage rich in bioactive phytochemicals. This study investigated the effect of brewing method on the profile of potential bioactive compounds in different coffee beverages using metabolomics and lipidomics based on UHPLC-MS/QTOF. The oil contents of the espresso coffee (EC), pot coffee (PC), instant coffee (IC), and filter coffee (FC) beverages studied were 0.13% ± 0.002, 0.12% ± 0.001, 0.04% ± 0.002, and 0.03% ± 0.003, respectively. Univariate analysis indicated significant differences (P < 0.001) in oil content when EC and PC beverages were compared with IC and FC beverages. Principal component analysis revealed similarities in the lipid profiles of FC and EC beverages and the hydrophilic profiles of PC and FC beverages. The EC beverage had the highest intensity of hydrophilic compounds such as adenine, theobromine, chlorogenic acid, and caffeine. The PC beverage was the most abundant in triglycerides, phosphatidylcholine, and diterpenes. Cafestol and kahweol esters, but not their free forms, were the most abundant diterpenes in the PC beverage. This work provides information on the differences in the profile of potentially bioactive compounds in four commonly consumed coffee beverage types and, thus, on the possible differences in the health effects of these coffee beverage types.

Genome-wide analysis and identification of Carotenoid Cleavage Oxygenase (CCO) gene family in coffee (coffee arabica) under abiotic stress.

The coffee industry holds importance, providing livelihoods for millions of farmers globally and playing a vital role in the economies of coffee-producing countries. Environmental conditions such as drought and temperature fluctuations can adversely affect the quality and yield of coffee crops.Carotenoid cleavage oxygenases (CCO) enzymes are essential for coffee plants as they help break down carotenoids contributing to growth and stress resistance. However, knowledge about the CCO gene family in Coffee arabica was limited. In this study identified 21 CCO genes in Coffee arabica (C. arabica) revealing two subfamilies carotenoid cleavage dioxygenases (CCDs) and 9-cis-epoxy carotenoid dioxygenases (NCED) through phylogenic analysis. These subfamilies exhibited distribution patterns in terms of gene structure, domains, and motifs. The 21 CaCCO genes, comprising 5 NCED and 16 CCD genes were found across chromosomes. Promoter sequencing analysis revealed cis-elements that likely interact with plant stress-responsive, growth-related, and phytohormones, like auxin and abscisic acid. A comprehensive genome-wide comparison, between C. arabica and A. thaliana was conducted to understand the characteristics of CCO genes. RTqPCR data indicated that CaNCED5, CaNCED6, CaNCED12, and CaNCED20 are target genes involved in the growth of drought coffee plants leading to increased crop yield, in a conditions, with limited water availability. This reveals the role of coffee CCOs in responding to abiotic stress and identifies potential genes useful for breeding stress-resistant coffee varieties.

Assessing one-shade composite resin color stability in response to everyday drinks.

OBJECTIVE: The aim of our study was to measure the color changes in one-shade composite resins when exposed to common drinks, such as tea, cola and coffee. MATERIALS/METHODS: In our study, Omnichroma, Vitrra APS Unique, GC A'chord and Charisma Diamond One composite resins were used. Composite resins were placed in stainless steel molds with depths of 2 mm and diameters of 5 mm. Ten specimens were immersed in tea, 10 specimens were immersed in coffee, 10 specimens were immersed in cola and 10 specimens were immersed in distilled water in an incubator at 37 °C for 14 days. Color measurements were performed at the beginning of the study and after 24 h and 14 days. Color values ​​were measured using a CIE L*a*b* system with a spectrophotometer device. Color and translucency changes were calculated and data analyzed using one-way ANOVA, two-way ANOVA, and post-hoc Tukey test (p < 0.05). RESULTS: The greatest color changes occurred in the tea and coffee groups; the smallest color change occurred in the control group. After 14 days, the greatest color change was observed in the Charisma + Coffee group; the smallest color change was observed in the Omnichroma + Water group. The transparency and contrast ratios changed in all groups, and the smallest change occurred in the Omnichroma control group. CONCLUSION: Significant differences were found in the composite color changes after immersion in beverages. The color variations significantly differed depending on the beverage in which the specimens were immersed. The initial contrast ratio was markedly different from the examined materials. CLINICAL SIGNIFICANCE: The study emphasizes the significance of common beverages on the color stability of one-shade composite resins, underlining the need of appropriate material selection for long-term aesthetic effects in one-shade composite resin restorations.

Interaction between Habitual Green Tea and Coffee Consumption and ACTN3 Genotype in Association with Skeletal Muscle Mass and Strength in Middle-Aged and Older Adults.

BACKGROUND: Recent studies have suggested the potential benefits of habitual coffee and green tea consumption on skeletal muscle health. However, it remains unclear whether these benefits are modified by genetic factors, particularly the alpha-actinin-3 (ACTN3) genotype, which is associated with the skeletal muscle phenotype. This study aimed to investigate the interaction between habitual coffee or green tea consumption and the ACTN3 genotype in association with skeletal muscle mass (SMM) and strength. METHODS: This cross-sectional study was conducted on 1,023 Japanese middle-aged and older adults (619 females, aged 45-74 years) living in the community. SMM was gauged using a bioelectrical impedance spectroscopy device, and handgrip strength (HGS) was used to measure muscle strength. The ACTN3 genotype (RR, RX, and XX) was determined from blood samples. Sex-specific linear regression models were used to analyze the interactions between coffee or green tea consumption and the ACTN3 genotype in association with SMM and HGS. RESULTS: In females, a significant interaction was observed between green tea consumption and the ACTN3 genotype in association with HGS (P interaction < 0.05). Furthermore, stratified analysis revealed a positive association between green tea consumption and HGS, specifically in females with the ACTN3 XX genotype (P trend < 0.05). In males, no significant interactions were observed between coffee or green tea consumption and the ACTN3 genotype in association with SMM or HGS (P interaction > 0.05). CONCLUSION: Our findings suggest that the skeletal muscle strength benefits associated with habitual green tea consumption may be contingent upon sex and the ACTN3 genotype.

In Vitro Evaluation of Color and Surface Roughness Changes of Polyetheretherketone, Monolithic Zirconia, and Resin Nanoceramics Exposed to Staining Liquids.

BACKGROUND: This study aims to investigate color stability and surface roughness of polyetheretherketone (PEEK), zirconia, and hybrid ceramics while stored in different liquids. METHODS: A total of 240 specimens were prepared from monolithic zirconia, PEEK, and hybrid ceramics. All specimens were polished using rubber sets with different grain sizes. Color parameters (L*, a*, b*) were measured three times using a dental spectrophotometer in standard D65 lightning. Each group was divided into eight different groups to be kept in eight different solutions as distilled water, cola, red wine, tea, coffee, heptane, citric acid, and 50% ethanol. Specimens were held in solutions at 37°C for 12 days. Color measurements were repeated, and color change (ΔE) was calculated using the CIE Lab formula. RESULTS: The color difference of PEEK specimens was found above the clinically acceptable limit; however, color differences for monolithic zirconia produced by coffee were found within the clinically acceptable limits. ZR and HC specimens' color change values were found between threshold values (1<ΔE < 3.3). The differences observed in surface roughness levels amongst the ZR specimens could be caused by the polishing instrument and procedure. CONCLUSION: The color change of the materials was within acceptable limits, whereas the surface roughness increased more than 0.2 µm. Especially cola, heptane, and red wine significantly increased the mean surface roughness.