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In this paper, six novel mathematical models based on semi-empirical calculus are proposed and applied to characterise the oven-drying process of cement mortar composites reinforced with cellulosic fibres (CMCRCFs). The drying experiments were carried out on four levels of oven-drying temperatures (70, 85, 105, and 120 °C), with four different cellulosic fibres content (0, 5, 10, and 20 %). Obtained results were compared to those derived by regression analysis of six most typically used mathematical drying models (Newton, Page, Page modified1, Page modified2, Handerson Pabis, and Logarithmic) in addition to six proposed models. The regression accuracy of the drying process was evaluated by the coefficient of determination (R2), low mean square error (MSE), low root mean squared error (RMSE), and mean absolute error (MAE). Additional criteria were used to ensure more validity of the selected models. The obtained values indicate a highly accurate fit of the proposed model MR9, meaning that the proposed model can clearly interpret the experimental drying data and predict the dry state of CMCRCFs.

Abstract Background A growing body of evidence reports that agitation and encephalopathy are frequent in critically ill Covid-19 patients. We aimed to assess agitation’s incidence and risk factors in critically ill ARDS patients with Covid-19. For that purpose, we compared SARS-CoV-2 acute respiratory distress syndrome (ARDS) patients with a population of influenza ARDS patients, given that the influenza virus is also known for its neurotropism and ability to induce encephalopathy. Methods We included all the patients with laboratory-confirmed Covid-19 infection and ARDS admitted to our medical intensive care unit (ICU) between March 10th, 2020 and April 16th, 2021, and all the patients with laboratory-confirmed influenza infection and ARDS admitted to our ICU between April 10th, 2006 and February 8th, 2020. Clinical and biological data were prospectively collected and retrospectively analyzed. We also recorded previously known factors associated with agitation (ICU length of stay, length of invasive ventilation, SOFA score and SAPS II at admission, sedative and opioids consumption, time to defecation). Agitation was defined as a day with Richmond Agitation Sedation Scale greater than 0 after exclusion of other causes of delirium and pain. We compared the prevalence of agitation among Covid-19 patients during their ICU stay and in those with influenza patients. Results We included 241 patients (median age 62 years [53–70], 158 males (65.5%)), including 146 patients with Covid-19 and 95 patients with Influenza. One hundred eleven (46.1%) patients had agitation during their ICU stay. Patients with Covid-19 had significantly more agitation than patients with influenza (respectively 80 patients (54.8%) and 31 patients (32.6%), p

Abstract In this paper, we study the existence and multiplicity of ρ-concave positive solutions for a p-Laplacian boundary value problem of two-sided fractional differential equations involving generalized-Caputo fractional derivatives. Using Guo–Krasnoselskii fixed point theorem and under some additional assumptions, we prove some important results and obtain the existence of at least three solutions. To establish the results, Green functions are used to transform the considered two-sided generalized Katugampola and Caputo fractional derivatives. Finally, applications with illustrative examples are presented to show the validity and correctness of the obtained results.

Perovskite solar cells (PSCs) have demonstrated remarkable photovoltaic performance, positioning themselves as promising devices in the field. Theoretical calculations suggest that copper (Cu) can serve as an effective dopant, potentially occupying interstitial sites in the perovskite structure, thereby reducing the energy barrier and enhancing carrier extraction. Subsequent experimental investigations confirm that adding CuI as an additive to MAPbI3-based perovskite cells improves optoelectronic properties and overall device performance. Optimizing the amount of Cu (0.01 M) has been found to significantly enhance crystalline quality and grain size, leading to improved light absorption and suppressed carrier recombination. Consequently, the power conversion efficiency (PCE) of Cu-doped PSCs increased from 16.3% to 18.2%. However, excessive Cu doping (0.1 M) negatively impacts morphology, resulting in inferior optical properties and diminished device performance. Furthermore, Cu-doped PSCs exhibit higher stabilized power output (SPO) compared to pristine cells. This study underscores the substantial benefits of Cu doping for advancing the development of highly efficient PSCs.

Due to their detrimental and carcinogenic effects, synthetic organic dyes pose significant environmental and health risks. Consequently, addressing the bioremediation of industrial wastewater containing these organic dyes has become an urgent environmental concern. The adsorption using low-cost and green materials is one of the best alternative techniques for the removal of dyes. This study aims to investigate the use of chitin to eliminate Congo red (CR), an anionic dye, from wastewater. The chitin was produced from shrimp shell in a quick and environmentally friendly manner by utilizing a co-solvent (glycerol/citric acid (GLC)). The resulting adsorbent was characterized through various techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), and FT-IR spectroscopy. The effectiveness of CR removal with chitin was studied with respect to contact time, adsorbent dose, initial pH, equilibrium isotherms, and kinetic and thermodynamic parameters. It was observed that variations in the dye concentration and pH significantly influenced the removal of CR with chitin. Under optimal operating conditions (pH = 7, contact time = 130 min, temperature = 50 °C), the adsorption capacity reached 29.69 ± 0.2 mg/g. The experimental data revealed that CR adsorption onto a chitin adsorbent is better represented by a Langmuir isotherm.

Microbes in indoor environments are constantly being exposed to antimicrobial surface finishes. Many are rendered non-viable after spending extended periods of time under low-moisture, low-nutrient surface conditions, regardless of whether those surfaces have been amended with antimicrobial chemicals. However, some microorganisms remain viable even after prolonged exposure to these hostile conditions. Work with specific model pathogens makes it difficult to draw general conclusions about how chemical and physical properties of surfaces affect microbes. Here, we explore the survival of a synthetic community of non-model microorganisms isolated from built environments following exposure to three chemically and physically distinct surface finishes. Our findings demonstrated the differences in bacterial survival associated with three chemically and physically distinct materials. Alkaline clay surfaces select for an alkaliphilic bacterium, Kocuria rosea, whereas acidic mold-resistant paint favors Bacillus timonensis, a Gram-negative spore-forming bacterium that also survives on antimicrobial surfaces after 24 hours of exposure. Additionally, antibiotic-resistant Pantoea allii did not exhibit prolonged retention on antimicrobial surfaces. Our controlled microcosm experiment integrates measurement of indoor chemistry and microbiology to elucidate the complex biochemical interactions that influence the indoor microbiome.