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Hollow sphere titanium dioxide/silver nanoparticles (HST/AgNPs) were synthesized using a one-pot sol–gel method with ascorbic acid as a reducing agent. This approach aims to enhance the efficiency of dye-sensitized solar cells (DSSCs) by improving light harvesting. The synthesized HST/AgNPs were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), ultraviolet–visible spectroscopy (UV–Vis), and transmission electron microscopy (TEM) to analyze their structural, optical, and morphological properties. XRD results confirmed the anatase phase of TiO₂ and the presence of AgNPs, which enhanced scattering effects and promoted electron transfer. SEM and TEM analyses showed a uniform distribution of AgNPs on the hollow TiO₂ spheres, suggesting successful integration of silver. Optical properties assessed by UV–Vis spectroscopy revealed a broad absorption in the visible range due to localized surface plasmon resonance effects from AgNPs. DSSCs incorporating HST/AgNPs demonstrated a 52% increase in efficiency compared to those using standard P25 TiO2, as shown by I–V meter analysis. However, a higher concentration of AgNPs reduced DSSC efficiency, likely due to decreased dye loading. The study also explored co-sensitization using peonidin (Pn) and pelargonidin (Pg) to broaden the visible light absorption range. While co-sensitization increased the absorption area under the visible spectrum curve, it did not significantly expand the absorption band. These findings emphasize the need to balance nanoparticle concentration and dye loading to optimize DSSC performance, contributing to the development of efficient solar cells and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) receive great attention for their wide spectrum of applications ranging from catalysis to biomedical applications. Despite the progressively growing scope of their functionalization and application, the synthesis method to achieve the material in such a short time and high yield is still a challenge. In this study, we performed the electrochemical preparation of MIL-101(Fe)-NH2 for the first time. The obtained material exhibited similar physico-chemical properties compared to those prepared with a solvothermal method. Analysis using X-ray diffraction (XRD) showed that the electrochemically-synthesized MIL-101(Fe)-NH2 demonstrates high suitability with the standard pattern at 2θ 9.28, 10.3, and 16.72°. Further analysis using Fourier Transform Infrared Spectroscopy (FTIR) confirmed that the proposed method had successfully produced the desired materials, as observed from the shift of C = O bond absorption band from 1688 cm− 1 to lower wavenumber and the presence of C-N bond at 1336 cm− 1 as well as the asymmetrical and symmetrical stretching vibration of N-H at 3470 and 3368 cm− 1. Nitrogen sorption isotherm confirmed the material occupies micro-porosity with an average pore size of 2.6 nm. The Field Emission Scanning Electron Microscopy-Energy Dispersive Spectroscopy (FESEM-EDS) and Transmission electron Microscopy (TEM) analysis revealed that the material occupies a micro-spindle shape. Moreover, Thermogravimetric analysis (TGA) showed that the material is thermally stable up to 250 ℃. Loading of curcumin into MIL-101(Fe)-NH2 via a post-synthesis strategy showed that solvothermal-synthesized MIL-101(Fe)-NH2 (MIL-101(Fe)-NH2-S) exhibited the highest loading efficiency up to 91.7% in 48 h. The release study revealed that the slowest release of the drug was observed in MIL-101(Fe)-NH2-S in an acidic medium (pH 4.8) and the release kinetic followed the non-Fickian diffusion. [ABSTRACT FROM AUTHOR]

The manuscript presents a pilot study of the impact of orthodontic intervention on the brain electrical activity. The orthodontic treatment is a powerful factor of both physiological influence on the jaw system and the surrounding tissues of the head and stress influence. All practically healthy subjects of the same age category (18–25 years) were distributed among three groups based on the method of orthodontic treatment. Group 1 included patients using braces, groups 2 and 3 included patients using aligners in which pressure was applied to 3–5 or 1–2 teeth, respectively. Brain activity electroencephalographic data were collected twice during neurophysiological monitoring: before and after orthodontic correction. The collected data sets included EEG signals from the occipital region of the brain. Numerical processing was performed based on continuous wavelet analysis to estimate the number and duration of oscillatory patterns in narrow frequency bands from 1 to 50 Hz. An assessment of the oscillatory brain activity demonstrated that different grades of correction intensity, regarding the dentition and occlusion, lead to uniform changes in the oscillatory patterns assessed by the electroencephalography in the occipital lobe. Comparison of the number of oscillatory patterns in the groups showed significant changes in the high-frequency ⋃ HF ∋ 16 ; 18 , 20 ; 28 , 32 ; 34 , 42 ; 50 Hz. The number of patterns in the ⋃ HF -band increases when using the most intense bracket devices; while in cases of more gentle correction based on aligner systems, it remains unchanged or even decreases. The independent clustering procedure by assessing changes in oscillatory processes of ⋃ HF -band occurring in a single occipital O1-canal made it possible to divide the data array into three clusters. The clusters of changes in brain activity correspond to clinical groups of patients. Thus, different types of dental exposure lead to significantly different changes in the brain activity of patients. [ABSTRACT FROM AUTHOR]

Indonesia has numerous lakes; however, research on the spatiotemporal sediment quality and source identification in lakes remains limited. The overaccumulation of heavy metals and nutrients in lakes severely threatens aquatic ecosystems. This study aims to identify potential sources of metallic deposits (Cu, Pb, Cr, Fe, Al, and Cd) and nutrients (TN and TP) in lake-surface sediment, utilizing enrichment factors (EF), geoaccumulation indices (Igeo), potential ecological risk indices (Er), and risk indices (RI). Multivariate statistical analyses, including principal component analysis (PCA) and Pearson's correlation analysis, were conducted to pinpoint pollution sources linked to land use. Eight sampling sites for surface sediment and water were examined in both wet and dry seasons at Menjer Lake, chosen for its diverse applications in tourism, hydropower, floating net cages, and extensive agriculture in its catchment. Correlation and PCA results indicated that Pb, Fe, and Al mainly originate from tourism, while Al, Fe, TN, and TP are associated with agriculture. The highest average loading from land use was observed in agriculture (> 0.8), floating net cages (> 0.76), and tourism (> 0.68). Furthermore, the highest loading from nutrients and all metals were TP (> 0.71) and all metals (> 0.35), respectively. Ecological risk assessment revealed low to moderately polluted EFs and Igeo in the dry season. However, Menjer Lake's Er and RI for heavy metals were generally classified as unpolluted. [ABSTRACT FROM AUTHOR]

Increasing the number of phases in step-down dc converters allows to increase power and has a positive effect on the energy efficiency of the converters. However, there is a problem of phase-current imbalance in such converters, which leads to uneven loading of the phases and does not allow to achieve the design power and efficiency. The article provides an overview of existing methods for current balancing in multiphase converters, and discusses their advantages and disadvantages. [ABSTRACT FROM AUTHOR]

This study aims to explore governmental leadership in response to global pandemic. A total of 52 articles from Scopus database were analyzed using Leximancer 4.51, followed by a content analysis. The findings are: (1) There are two concept changes, namely crisis labeling and a change in the meaning of masculine versus feminine which is embedded in leader's decisions; (2) The theories that support the phenomenon of leadership are quite diverse; (3) The most common methodology is case study. The limitations of the study, especially in the articles analyzed during the coronavirus outbreak. We suggest future research directions into historical perspective. [ABSTRACT FROM AUTHOR]

In the quest to treat diabetes, nowadays, the enthusiasm for the development of novel drugs with strong α-glucosidase inhibitory action and negligible or no adverse effects has received great attention. Herein, to gain a deeper knowledge of the molecular interactions of inhibitors with α-glucosidase, straightforward integration of molecular modeling studies was demonstrated on a series of 2,5-disubstituted furan derivatives possessing a wide range of potent α-glucosidase inhibitors. To determine the structural need for α-glucosidase inhibition, CoMFA, docking, and molecular dynamic (MD) studies were performed. We discovered that the phenyl ring substituent selection and the presence of a 1,3,4-thiadiazole moiety are critical for controlling α-glucosidase inhibition. Furthermore, the density functional theory (DFT) was carried out to predict the electronic properties of ligands. Subsequently, the screened molecules were further inspected for their ADMET and drug-likeness properties. Besides, an inverse virtual screening (IVS) revealed that the screened compounds have the potential as aldose reductase inhibitors. Overall, combining the computational investigations enabled us to acquire a comprehensive understanding of 2,5-disubstituted furan derivatives and the role of their structures in interaction with α-glucosidase, and they may be employed for the design of antidiabetic drugs in the future. [ABSTRACT FROM AUTHOR]

Controlling the premature release of hydrophobic drugs like quercetin over physiological conditions remains a challenge motivating the development of smart and responsive drug carriers in recent years. This present work reported a surface modification of mesoporous silica nanoparticles (MSN) by a functional compound having both amines (as a positively charged group) and carboxylic (negatively charged group), namely 4-((2-aminoethyl)amino)-4-oxobut-2-enoic acid (AmEA) prepared via simple mechanochemistry approach. The impact of MSN surface modification on physical, textural, and morphological features was evaluated by TGA, N2 adsorption–desorption, PSA-zeta, SEM, and TEM. The BET surface area of AmEA-modified MSN (MSN-AmEA) was found to be 858.41 m2 g−1 with a pore size of 2.69 nm which could accommodate a high concentration of quercetin 118% higher than MSN. In addition, the colloidal stability of MSN-AmEA was greatly improved as indicated by high zeta potential especially at pH 4 compared to MSN. In contrast to MSN, MSN-AmEA has better in controlling quercetin release triggered by pH, thanks to the presence of the functional groups that have a pose-sensitive interaction hence it may fully control the quercetin release, as elaborated by the DFT study. Therefore, the controlled release of quercetin over MSN-AmEA verified its capability of acting as a smart drug delivery system. [ABSTRACT FROM AUTHOR]

Bio-metal–organic framework (Bio-MOF) is a type of MOF which is promising in biomedical applications, including for slow-released hydrophobic drugs, for example, curcumin. In this research, we investigated the influence of surface modification of MIL-100(Fe) with carboxymethyl cellulose (CMC) and its profile in the slow-release of curcumin at different pH. MIL-100(Fe) was synthesized by the dry gel conversion (DGC) method. XRD and FTIR analysis confirmed that MIL-100(Fe) was successfully synthesized. Based on the nitrogen sorption isotherm measurement, MIL-100(Fe) is classified as micro-porous material. Morphological analysis using SEM and TEM showed that the MIL-100(Fe) formed aggregates with an average particle size of 7.37 ± 2.21 nm. Curcumin was successfully encapsulated into MIL-100(Fe) in ethanol: water with a volume ratio of 1: 1 for 48 h to produce cur@MIL-100(Fe) and has drug loading capacities of 19.267 mg/g, and drug loading efficiency up to 792.324 mg/g. Furthermore, cur@MIL-100(Fe) was modified ex-situ using CMC to form cur@MIL-100(Fe)@CMC. The release of curcumin from cur@MIL-100(Fe) and cur@MIL-100(Fe)@CMC was carried out in a 1% tween-phosphate-buffered saline (PBS) solution medium (at pH 5.8 and pH 7.4). The concentration of curcumin released was determined based on the absorbance observed on the UV–Vis spectrophotometer. Cumulative percent release (CPR) of curcumin from cur@MIL-100(Fe) at 48 h reached 82.21 ± 3.0% in tween-PBS media pH 5.8 and 40.10 ± 3.35% in tween-PBS media pH 7.4, and shows constant results afterward. The CPR of curcumin from cur@MIL-100(Fe)@CMC at 48 h reached 5.94 ± 0.02% in a tween-PBS solution of pH 5.8, and 7.64 ± 0.05% in a tween-PBS solution at pH 7.4. The presence of CMC is able to suppress the release of excessive curcumin from MIL-100(Fe) and this system shows a different release profile at different pH, so it has the potential to be used as a pH-responsive drug delivery system. [ABSTRACT FROM AUTHOR]

We propose a Task and Motion Planning algorithm for a robot manipulator to rearrange objects in a narrow and highly-dense workspace. In such a workspace, there may not be enough space to rearrange the objects that obstructs the way for a robot manipulator to access a target object. The present work aims to relocate as few objects (so called obstacles) as possible for the robot manipulator to grasp the target object successfully. The proposed algorithm seeks both the sequence of obstacles to be rearranged and the corresponding places to move them. A heuristic search is employed to find a rearrangement sequence and places. Especially, in the proposed algorithm, stacking an object on the top of other objects is allowed, while searching a place to rearrange obstacles. Virtual simulations and real robot experiments show that the proposed algorithm works reasonably for dense real-world environments. [ABSTRACT FROM AUTHOR]

In this research, the performance of metal–organic frameworks (MOFs) of MIL-101(Fe) and MOF-808 as aspirin detoxification agents was evaluated. MIL-101(Fe) was successfully prepared for the first time using the electrochemical method for 30 min under room temperature and pressure. MIL-101(Fe) detoxification capacity was compared to that of MOF-808, which was synthesized by a common solvothermal method at 135 °C for 24 h. The obtained materials were fully confirmed by X-ray diffraction (XRD) with the appearance of MIL-101(Fe) characteristic peaks (at 2θ 8.5°; 9°;16.7°) and MOF-808 (at 2θ 8.3°; 8.7°; 10°; 10.9°), and also confirmed by Fourier transform infrared (FTIR) spectroscopy that shows the coordination between metal and ligand. Based on scanning electron and transmission electron microscopy (SEM and TEM), MIL-101(Fe) has a micro-spindle shape with average particles size of 649.12 ± 73.32 nm, while MOF-808 showed irregular shape with average particle sizes of 169.73 ± 31.87 nm. Nitrogen sorption isotherm confirmed that both materials could be classified as micro to-meso porous materials by the pore radius of 1.89 nm for each materials with BET surface areas of 131 for MIL-101(Fe), and 847 m2/g for MOF-808, respectively. Based on an in vitro test, in a gastric simulation, MIL-101(Fe) decreased 11.78% of aspirin, while MOF-808 decreased 7.99%. In the intestinal simulation, MIL-101(Fe) and MOF-808 decreased aspirin by 24.06% and 26.74%, respectively. XRD analysis of the MOFs after the detoxification test showed that MIL-101(Fe) has lower stability than MOF-808. FTIR spectra confirmed that aspirin was successfully adsorbed into the MOFs. Transmission electron microscopy showed that aspirin interacted with MIL-101(Fe) on the outer surface and with MOF-808 on the inside of the pores. [ABSTRACT FROM AUTHOR]

As a biocompatible porous material, bio-MOF is a very promising material as a carrier for hydrophobic drugs, including curcumin. However, the stability of bio-MOF against water and humidity still needs to be improved; therefore, surface modifications are required. This study aims to modify the MIL-100(Fe)-based bio-MOF through core–shell architecture by employing mesoporous silica nanoparticles (MSNs or SiO2) for improving the stability and performance of MIL-100(Fe) to provide a slow-release feature of curcumin. The composites were synthesized via sonochemistry-assisted or mechanochemistry-assisted green protocol to form core–shell structure of MIL-100(Fe)@SiO2 (Composite-1) or SiO2@MIL-100(Fe) (Composite-2). Structural, textural, and morphological analyses, including XRD, FTIR, SEM, TEM, and N2 adsorption–desorption, are discussed in this study to evaluate the composite formation. BET surface area of the MIL-100(Fe) decreased from 1197.45 m2/g to 565.63 and 823.70 m2/g after forming composite-1 and composite-2 with SiO2. The loading capacity, however, just increased slightly up to 97.89% after the modification. The presence of SiO2 as shell (composite-1) protects the MIL-100(Fe) from degradation under the acidic condition at pH 5.8 and can maintain the slow-release of curcumin. In contrast, the presence of SiO2 as core (composite-2) induces the sustained release due to faster degradation of MIL-100(Fe) in acidic condition. Both composites serve as a model for either sustained release or delayed release drug delivery systems. [ABSTRACT FROM AUTHOR]

The authors aimed at analyzing the costs of inpatient care of schizophrenia in Kiel (Germany). The study was also to present treatment regimens used at the German Academic Center. Moreover, the study is a continuation and complement of the previous study conducted in Polish and Ukrainian Academic Center. Therefore, it helps increase the awareness and knowledge of residents concerning the cost of inpatient care of schizophrenia. The analysis was based on 105 hospital records of patients treated between January 2012 and June 2013. According to inclusion criteria, 50 adult patients (27 women and 23 men) were included in the study. The study was approved by the Ethics Committee of the Medicine Faculty of CAU in Kiel. The cost of schizophrenia treatment of 50 patients in Kiel was EUR 604,280.90 ( $$\bar{x}$$ = EUR 12,085.62). The duration of hospital stay was on average $$\bar{x}$$ = 51.02 days. The patients were treated with neuroleptics of all generations. The most popular atypical neuroleptic was amisulpride and the most popular typical neuroleptic was haloperidol. Patients from Kiel were provided a comprehensive non-pharmacological treatment. Treatment regiments and evaluations of costs of schizophrenia vary between countries. The costs of inpatient care of schizophrenia are high in Kiel. Treatment of schizophrenia seems to be comprehensive in Kiel and wide range of treatment opportunities contribute to a more effective treatment confirmed by less frequent relapses of schizophrenia than in Lviv (Ukraine), for example. Comprehensive treatment should be available everywhere, because it is a right of every patient. [ABSTRACT FROM AUTHOR]

Schizophrenia is a severe and chronic disorder requiring long-lasting and comprehensive treatment. Because of this disorder patients are socially isolated. Consequently, schizophrenia has a significant economic burden both in a group of direct and indirect costs. The aim was to analyse experts' opinions in the field of psychiatry concerning work possibilities among people with schizophrenia and to present the importance of employment for more effective treatment. A worldwide study was conducted between June 2011 and June 2013 using a questionnaire consisting of six open-closed questions and a short metrics. The questionnaire was delivered to experts and spread all over the world by post and via the internet. Over 3000 questionnaires were sent and the addressed specialists were requested to return them. From received 403 questionnaires 320 were included into the study, based on adopted inclusion and exclusion criteria. Although patients are afraid of looking for a job, respondents indicated that they crave for employment. The number of people that are able to work during remission of schizophrenia is considerably higher (50.35 %) than the number of actually employed (15.85 %). Non-pharmacological therapies were indicated as important to improve patients′ chances of finding a job during remission of schizophrenia. The number of people that can work during remission of schizophrenia is considerably higher than the number of affected people employed. Patients crave for a job and supported employment should be treated as priority by health-care decision makers. [ABSTRACT FROM AUTHOR]

On the basis of an analysis of the kinetics of rupture and data on breakdown of gas pipes the article suggests a classification of ruptures. This makes it possible to classify each special case of rupture either as local-type or as global avalanche-type rupture. [ABSTRACT FROM AUTHOR]