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The vision transformer (ViT) architecture, with its attention mechanism based on multi-head attention layers, has been widely adopted in various computer-aided diagnosis tasks due to its effectiveness in processing medical image information. ViTs are notably recognized for their complex architecture, which requires high-performance GPUs or CPUs for efficient model training and deployment in real-world medical diagnostic devices. This renders them more intricate than convolutional neural networks (CNNs). This difficulty is also challenging in the context of histopathology image analysis, where the images are both limited and complex. In response to these challenges, this study proposes a TokenMixer hybrid-architecture that combines the strengths of CNNs and ViTs. This hybrid architecture aims to enhance feature extraction and classification accuracy with shorter training time and fewer parameters by minimizing the number of input patches employed during training, while incorporating tokenization of input patches using convolutional layers and encoder transformer layers to process patches across all network layers for fast and accurate breast cancer tumor subtype classification. The TokenMixer mechanism is inspired by the ConvMixer and TokenLearner models. First, the ConvMixer model dynamically generates spatial attention maps using convolutional layers, enabling the extraction of patches from input images to minimize the number of input patches used in training. Second, the TokenLearner model extracts relevant regions from the selected input patches, tokenizes them to improve feature extraction, and trains all tokenized patches in an encoder transformer network. We evaluated the TokenMixer model on the BreakHis public dataset, comparing it with ViT-based and other state-of-the-art methods. Our approach achieved impressive results for both binary and multi-classification of breast cancer subtypes across various magnification levels (40×, 100×, 200×, 400×). The model demonstrated accuracies of 97.02% for binary classification and 93.29% for multi-classification, with decision times of 391.71 and 1173.56 s, respectively. These results highlight the potential of our hybrid deep ViT-CNN architecture for advancing tumor classification in histopathological images. The source code is accessible: https://github.com/abimouloud/TokenMixer. [ABSTRACT FROM AUTHOR]

In this study, we report the synthesis of iron oxide nanoparticles (FeONPs) using micro-emulsion-hydrothermal method. By adjusting the synthesis temperature, we successfully produced FeO nanorods and nanospheres. In addition, the 2-octanol, and the surfactant cetyltrimethylammonium bromide served as a solvent in the synthesis process. Using iron nitrate hexahydrate as the salt precursor allowed for the formation of FeONPs with varied sizes, shapes and phases. The synthesized materials were extensively characterized using XRD, SEM, TEM, EDS, FTIR, and XPS techniques. However, the structural analysis revealed rhombohedral (hematite), and (magnetite) crystal structures in the materials synthesized at different temperature and durations, with particles ranged in size from 12 to 97 nm. More importantly, the magnetic characterization, performed with a vibrating sample magnetometer and SQUID magnetometer, indicated that the NPs showed not clear superparamagnetic behavior. In conclusion, this work demonstrates the synthesis of FeONPs with controlled size, shape and phase using microemulsion hydrothermal technique, with detailed characterization offering valuable insights into their magnetic and structural properties. [ABSTRACT FROM AUTHOR]

Breast cancer (BC) is a widespread and lethal cancer affecting women world- wide. Early diagnosis plays a pivotal role in ensuring survival, as late detection can result in a fatal outcome. Convolutional neural networks (CNNs) have made significant contributions to the task of medical imaging modalities and have dis- played promise in addressing this challenge. Recently, the success of the vision transformer (ViT) architecture has encouraged the use of the attention mecha- nism in computer-aided diagnosis (CAD) tasks. However, the ViT is known for its data-intensive nature and a substantial number of parameters and needs power- ful computer resources when training, which often leads to the same performance compared to CNNs. These challenges are particularly evident in tasks involving medical image datasets with complex images and limited data. This problem- atic situation led to the suggestion three of low-weight parameter systems based on convolution and attention techniques: vision transformer base model (ViT), compact convolution transformers (CCT), and lightweight mobile vision trans- formers (MVIT). These systems are developed by using the BreakHis dataset, which includes images captured at different magnification levels (40x, 100x, 200x, 400x), for both binary and multi classification of breast cancer subtypes. These low-weight hybrid ViT-CNN networks operate directly on input patches and convolution layers, to improve feature extraction and attention layers to train patches in all networks. This approach results in lower training time and fewer parameters while achieving accurate breast tumors classification. The proposed method is based on splitting the input image into patches and then focusing them on the area of cancerous lumps, providing a sequence of linear embedding of these patches as input. Second, we applied a convolution layer directly to the histopathology input patches, with the fewest possible modifications. Finally, we train patches in all transformer encoder layers to evaluate the performance of the classification of breast subtypes. The performance accuracies of our suggested models are 98.64% for VIT, 96.99% for CCT and 97.52% for MVIT. Moreover, the proposed models were compared with state-of-the-art models using the same dataset. Our study demonstrates how convolution and attention mechanisms can minimize computational training resources and decision time, to develop high- performing computer-aided analyses for breast cancer diagnosis. The source codes are accessible at https://github.com/abimouloud/ViT-CNN. [ABSTRACT FROM AUTHOR]

Cholesteatoma is a common disease of the middle ear cleft associated with several complications, Surgery is the mainstay for the management of such a pathological condition, however, complications may occur including intracranial ones due to violation of middle cranial fossa dura. Anatomical variations have been reported and High-resolution CT scan is the major tool for detecting such variations. In this study, we aim to determine if there is a difference between tegmen height between both sides of patients with unilateral cholesteatoma. 21 patients were recruited for such study all underwent HRCT and the tegmen height was determined in two coronal planes, the first between the central point of the Henle spine and the tegmen, the other between the plane of both lateral canals and the roof of the middle ear. The tegmen height measurements showed that the affected side had significantly lower tegmen height Henle spine (6.30 ± 1.54 vs. 9.03 ± 1.34 (mm); p < 0.001) relative to the healthy side. Also, coronal plane measurement has shown statistical significance for tegmen height (2.98 ± 0.79 vs. 4.15 ± 0.76 (mm); p = 0.01) in comparison to the healthy side. The percentage of difference between both sides as regards tegmen height of Henle's spine and coronal measurement was 30.32% and 28.2%, respectively. A significant difference was found in tegmen height between healthy and diseased sides in patients with unilateral cholesteatoma. [ABSTRACT FROM AUTHOR]

Soft denture liners have limitations like short lifespan and increased microbial buildup. Despite promise as a non-leaching antimicrobial polymer in dentistry, the impact of dimethylaminododecyl methacrylate (DMADDM) on soft liner performance remains unexplored. This study aimed to evaluate the effect of integrating different concentrations of DMADDM to cold cure acrylic resin soft liner, on its antimicrobial activity, cytotoxicity, and physical properties. The same properties were compared to a conventional commercially available denture soft liner. The study employed a control group (conventional soft liner) and three test groups containing 3.3%, 6.6%, and 10% (total mass fraction) DMADDM, respectively. Antimicrobial activity against Candida albicans and Streptococcus mutans was assessed through colony counts and biofilm biomass. Cytotoxicity was evaluated using an oral epithelial cell line. Additionally, wettability and hardness were measured to assess physical properties. Incorporation of DMADDM significantly reduced Candida albicans and Streptococcus mutans counts, and biofilm biomass, compared to the control. Additionally, DMADDM improved the soft liner's wettability and mitigated long-term hardness increase. In conclusion, DMADDM holds promise in enhancing soft liner performance. However, careful selection of its optimum concentration is crucial to ensure both safety and efficacy for future clinical use. [ABSTRACT FROM AUTHOR]

Currently, halide perovskites with exceptional properties are the most suitable candidates for RRAM devices. In the present study, a comprehensive investigation of structural, mechanical, optoelectronic and thermoelectric properties of Cs2BSnX6 (B = Mg, Cu; X = Cl, Br, I) has been conducted for the potential application in resistive switching random access memory (RRAM) devices. Mechanical properties display that studied perovskites exhibit mechanical stability and ductile behavior with an anisotropic character. A comparison of band structure using PBE-GGA, and TB-mBJ was also made. The band structure with TB-mBJ investigation disclosed that Cs2MgSnCl6, Cs2MgSnBr6, Cs2MgSnI6, Cs2CuSnCl6, Cs2CuSnBr6, and Cs2CuSnI6 have indirect bandgaps with value of 3.64 eV, 2.87 eV, 2.05 eV, 2.30 eV, 1.50 eV and 0.90 eV respectively. These values are found to be slightly more than PBE-GGA approximations. The optical investigation illustrates that Cs2CuSnI6 can absorb a wide range of electromagnetic radiation wavelengths from ultraviolet to infrared, making it the optimal candidate for RRAM devices. Thermoelectric properties show electrical conductivity values of the 1.65 × 1019, 1.61 × 1019, 1.58 × 1019, 1.95 × 1019, 2.35 × 1019, 2.40 × 1019 (Ω.m.s)−1 for Cs2MgSnCl6, Cs2MgSnBr6, Cs2MgSnI6, Cs2CuSnCl6, Cs2CuSnBr6, and Cs2CuSnI6 respectively at 1500 K. Furthermore, the calculated optical and thermoelectric properties of Cs2BSnX6 (B = Mg, Cu; X = Cl, Br, I) compared with previously studied Cs2CaSnX6 (X = Cl, Br, I), disclosing that Mg and Cu-based perovskites display better optical and thermoelectric properties. The vital findings of this study express that Cs2CuSnI6 is the most appropriate candidate for less-energy consuming RRAM devices among all studied perovskites. [ABSTRACT FROM AUTHOR]

The primary focus of this research is to conduct a comprehensive exploration of the preparation and description of a thin film composed of bimetallic sulphide, NiZr2S4. The fabrication process involved the utilisation of diethyldithiocarbamate, employing physical vapour deposition. To gain insights into the material's properties, an array of analytical techniques was employed to investigate its structure, morphology, and optical characteristics. A well-defined crystalline assembly with an approximate crystallite size of 42 nm, corresponding to a crystallinity of 77% was observed. Optical properties were evaluated to determine the material's bandgap energy at 2.7 eV. Through X-ray photoelectron spectroscopy, distinct core level peaks associated with Zr 3d, Ni 2p, and S 2p were identified, providing perceptions into the elemental configuration and chemical bonding of the thin film. Electrochemical properties were assessed through voltammetry measurements, revealing a notable specific capacitive performance of 543 Fg−1. The thin film exhibited remarkable stability over multiple cycles, putting it as a highly auspicious contender for various energy storage devices. Furthermore, extensive investigations were shown to evaluate the photocatalytic capabilities of the fabricated material, explicitly its efficiency in degrading various environmental pollutants. These significant findings underscore the versatility of bimetal sulphide thin films, spreading their potential beyond energy storage and paving the way for further research and technological advancements in areas such as photocatalysis and beyond. [ABSTRACT FROM AUTHOR]

Emotion recognition can be used in a wide range of applications. We are interested in the E-learning system because of the several benefits of learning anywhere and anytime. Despite important advances, students' emotions can influence the learning process, and this is the case with both traditional learning as well as E-learning. Emotion can limit and blocks our ability to learn, think, and solve problems. On the contrary, it can drive us to success by boosting our innate mental ability when we love what we do and when we are affected by happiness and excitement. In recent years, a large number of studies have addressed the problem of emotion recognition based on different modalities. But the information provided by student emotion recognition based on single-modal data like face is insufficient. Additionally, selecting one affective state over another might be challenging at times. To remove these ambiguities, we propose an Intelligent Affective Tutoring System named "Multimodal Intelligent Tutoring Emotion Recognition System" MITERS that merges three modalities such as face, text, and speech simultaneously. Our System is a real-time-based system that detects the emotion of students and gives adequate feedback. For this purpose, we use deep learning techniques. Among these are (a) Deep Convolution Neural Network (DCNN) used to detect emotion from face modality, (b) Bidirectional Long Short Memory (BiLSTM) for predicting emotions from text information, and (c) Convolutional Neural Network (CNN) which is used to detect emotions from speech modality. The experimental results are compared with some of the well-known approaches and the proposed MITERS has performed well with a classification accuracy of 97% in MELD which is a multimodal database. [ABSTRACT FROM AUTHOR]

A comprehensive investigation of the structural, microstructural, ferroelectric, and dielectric relaxation characteristics was accomplished on Gd-substituted barium bismuth titanate (BaBi4Ti4O15) (BBTO) Aurivillius ceramics. The Rietveld refined X-ray diffraction confirmed that the low-concentration (≤ 0.10) of Gd ions as a more stable orthorhombic with A21am phase and to higher concentration (> 0.10) as dual phase orthorhombic “A21am + F2mm” space group. The inherent plate-like grain morphology was characterized by a scanning electron microscope. A discernible microstructural phonon modification in Raman spectroscopy analysis exposed changes with temperature variations confirms of dual-phase pattern at increased dopant concentrations. T-dependent dielectric study reveals a shifting Curies Weiss ( T m ) transition towards lower temperature was noticed with an increase of Gd dopant. The relaxor ferroelectric phase transitions were detected using the modified Curie–Weiss law such as Vogel–Fulcher (VF), Cluster Glass (CG), and Stretched string (SS) models. The VF fitting was more stabilized for lower concentrations (Gd; x ≤ 0.10). Furthermore, the CG model was appropriate for the higher concentration of dopant (Gd; x > 0.10) indicating the stabilization of the relaxor ferroelectric nature. The temperature-dependent dielectric studies reveal a normal ferroelectric to relaxor ferroelectric crossover of 0.20 implying a reduction in interaction within the polar regions. The observed relaxor-like dielectric behavior suggests the generation of small-sized polar regions due to an imbalance of charge in compensation of the Bi2O2 layer for higher dopant concentrations. The randomly weak interaction between the small polar regions leads to a critically slowed down of polar regions dynamics below. The soft ferroelectric P-E loops with weak loop character of well predominant shape were observed in Gd-substitution BBTO ceramics. [ABSTRACT FROM AUTHOR]

Gd ion-substituted barium bismuth titanate (BaBi4Ti4O15; BBTO) Aurivillius ceramics were synthesized to understand the preliminary impact through the structural, optical, frequency-dependent dielectric, conductivity, and complex modulus spectroscopic studies. X-ray diffraction (XRD) study confirmed the phase purity and crystallinity of the orthorhombic crystal system with A21am space group. The room temperature Raman study was correlated with the XRD results revealing a more feasible Aurivillius phase. A shift in the Curie temperature (Tm) towards low-temperature regions with increasing concentrations of Gd dopant was observed in temperature-dependent conductivity studies. The frequency-dependent conductivity study revealed a diffuse relaxor signature that degraded with dopant concentration explained by the modified Curie–Weiss law and normalized dielectric permittivity study. The frequency and temperature dependent modulus spectroscopic study indicated a dielectric relaxation mechanism in the presence of doubly ionized oxygen vacancies in pristine BBTO ceramics whereas the dominance of singly ionized oxygen vacancies was observed in Gd-doped one. The dielectric relaxation mechanism for pristine and doped Aurivillius are explained due to the thermal motion of the localized hopping process of electrons in variable oxidation states of different single ionized ions that depart from ideal Debye behavior. A detailed ac-conductivity study revealed the jumping relaxation mechanism or correlated barrier hopping mechanism (CBM) because of the localization of charge carriers, or the formation of polarons, respectively. [ABSTRACT FROM AUTHOR]

To evaluate the biomimetic remineralization capabilities of Moringa oleifera leaves (MOL) extract on coronal dentin and acellular cementum, two different concentrations (50 and 200 mg/ml) of MOL extract loaded in plain varnish (M1 and M2 groups respectively) were compared to fluoride varnish (FL group) and native surface (C group). Eighty sound premolar teeth were collected. Forty teeth (10 teeth in each group) were used for coronal dentin testing while the other forty (10 teeth in each group) were used for acellular cementum testing. Teeth in M1, M2, and FL groups were etched for 30 s and then received the specific varnish treatment. All samples were immersed in artificial saliva for 14 days and then collected, dried, and examined by scanning electron microscopy and energy dispersive X-ray spectroscopy (EDX). Histologically, FL group showed mineral deposition as discrete vesicular granules of various sizes on the surface of both coronal dentin and acellular cementum. Mineral deposition only occurred on some DTs openings while opened tubules remained. The surface of the acellular cementum revealed regular grooves, micro-fissures, and cracks. In the M1 and M2 groups, mineral deposition appeared as a homogenous continuous layer on coronal dentin and acellular cementum. Only a few DTs and cementum fissures were not filled completely. In L.S. sections of the coronal one-third, the DTs appeared almost sealed with varying lengths of mineral deposition. EDX results statistical analysis showed that the M2 group had the highest phosphate ions (P−) and calcium ions (Ca+2) at%. MOL has an extraordinary effect on the remineralization of coronal dentin and acellular cementum. It would have a promising ability to control dentinal hypersensitivity and formation of biomimetic cementum tissue. [ABSTRACT FROM AUTHOR]

Three metal ammonium (ammonia) carbonate double salts were mechanochemically synthesized including magnesium ammonium carbonate ([NH4]2Mg[CO3]2·4H2O, MAC), copper ammonium carbonate ([NH3]2Cu(CO3), CAC), and zinc ammonium carbonate ((NH3)Zn(CO3), ZAC), and their crystallinity and thermal stability were investigated using in situ X-ray diffraction. The crystal structures were investigated in the temperature interval from 25 to 355 °C. MAC exhibited relatively low thermal stability with its crystal structure rapidly losing crystalline water as well as ammonium ions already at 85 °C and transforming into an amorphous carbonate, as confirmed by in situ infrared spectroscopy. CAC and ZAC exhibited loss of the corresponding NH3 at much higher temperatures transforming into a mixture of the corresponding metal oxides according to the XRD with the outer layer of the carbonate, as suggested by infrared spectroscopy measurements. The thermogravimetric analysis has been carried out to investigate the thermal degradation behavior. Initial fast mass loss was observed in the parent [NH4]2CO3 already under 100 °C with complex mass loss patterns from basic carbonate precursors achieving stable mass at above 500 °C for magnesium carbonate. CAC and ZAC inherited intermediate responses to temperature when compared to the precursors exhibiting stable mass at ~ 300 °C. This can be associated with the distinct crystal structure of the compounds whereby CAC and ZAC exhibit strong bonds with metal ions, while in MAC crystalline water contributes to lower stability of the crystal as well as the loosely bound ammonium ion. Infrared spectra were obtained and interpreted at room temperature followed by their in situ thermal analysis up to 250 °C in attenuated total reflection mode. Changes in the complex room temperature spectra with increasing temperature were interpreted as loss of N–H bonds, as confirmed by the concurrent decrease in the 3350–3000 and 1248 cm−1 band region. It was found that ZAC was the most thermally stable compound among the three double salts. The thermal data obtained in this work have practical implications for nutrient recovery and their release in the environment. [ABSTRACT FROM AUTHOR]

The work demonstrates the development of an electrochemical sensor for quantification of Chloramphenicol (CA) using pencil graphite electrode (PGE) modified with Gadolinium tungstate nano flakes and carbon nano fibers composite (PGE/GWNfs/CNFs). The composite was further characterized and confirmed by X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy, transmission electron microscopy analysis. The prepared GWNfs/CNFs nano composite was fabricated by drop casting method to get PGE/GWNfs/CNFs working electrode. The modified electrode is then analyzed by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV) methods for its electrochemical and electrocatalytic property. The electrochemical investigation of developed sensor shows enhanced activity towards electro-oxidation of CA. The DPV studies revealed high efficacy characteristics such as sensitivity in the range 0.03984 µA µM−1 cm−2, selectivity, good linear range (5–50 μM), and low detection limit (0.4 μM). The study benchmarks the use of GWNfs/CNFs as an excellent transducer material in electrochemical sensing of CA in standard samples thus, it finds an efficient potential application in the analysis of CA in environment sample analysis. [ABSTRACT FROM AUTHOR]

Objective: To assess the influence of patient characteristics, anatomical conditions, and technical factors on radiation exposure during prostatic arteries embolization (PAE) performed for benign prostatic hyperplasia. Materials and methods: Patient characteristics (age, body mass index (BMI)), anatomical conditions (number of prostatic arteries, anastomosis), and technical factors (use of cone beam computed tomography (CBCT), large display monitor (LDM), and magnification) were recorded as well as total air kerma (AK), dose area product (DAP), fluoroscopy time (FT), and number of acquisitions (NAcq). Associations between potential dose-influencing factors and AK using univariate analysis and a multiple linear regression model were assessed. Results: Forty-one consecutive men (68 ± 8 years, min–max: 40–76) were included. LDM and CBCT decreased the use of small field of view with 13.9 and 3.8% respectively, both p < 0.001. The use of a LDM significantly reduced AK (1006.6 ± 471.7 vs. 1412 ± 754.6 mGy, p = 0.02), DAP (119.4 ± 64.4 vs. 167.9 ± 99.2, p = 0.04), FT (40.4 ± 11.5 vs. 53.6 ± 25.5 min, p = 0.01), and NAcq (16.3 ± 6.3 vs. 18.2 ± 7, p = 0.04). In multivariate analysis, AK reduction was associated with lower patient BMI (β = 0.359, p = 0.002), shorter FT (β = 0.664, p < 0.001) and CBCT use (β = − 0.223, p = 0.03), and decreased NAcq (β = 0.229, p = 0.04). Conclusion: LDM and CBCT are important technical dose-related factors to help reduce radiation exposure during PAE, and should be considered in standard practice. Key Points: • The use of large display monitor (LDM) and cone beam computed tomography (CBCT) both decreased the need for magnification during prostatic arteries embolization (PAE). • The use of LDM reduces radiation exposure during PAE. • Total air kerma is associated with patient's body mass index, fluoroscopy time, CBCT, and the number of acquisitions. [ABSTRACT FROM AUTHOR]

In this work, spent coffee grounds (SCG) were treated using sulfuric acid hydrolysis in order to isolate the sulfuric acid lignin (SAL). The reactivity of SAL was improved through phenolation and acetylation. Spectroscopic analysis showed that the isolated lignin is composed of GHS type and it was characterized by a high amount of (C–C) and β-O-4 bonds. The thermal analysis showed that the phenolated sulfuric acid lignin (Ph-SAL) present higher thermal stability compared to SAL and acetylated sulfuric acid lignin. In addition, the phenolic hydroxyl group content increases from 2.99 to 9.49 mmol/g after phenolation. Moreover, a methylene blue (MB) adsorption test was established in order to find out the sorption capacity of different samples. The study showed that the adsorbed amount of dye increase after the chemical modification of SAL, especially after phenolation. The removal efficiency was enhanced after modification to reach 99.62% for Ph-SAL. The evaluation of the adsorption experimental data with the theoretical models of Langmuir and Freundlich showed that the best fitting was expressed by the Langmuir model for all samples. Finally, this study showed that lignin isolated from SCG can be simply and easily chemical modified and exhibits excellent adsorption ability towards cationic dyes (MB) in aqueous solutions. As a renewable, low-cost, and natural biomass material, lignin from SCG shows a promising practical and economical application of biomass in the field of wastewater purification. [ABSTRACT FROM AUTHOR]

Two patients underwent percutaneous image-guided electrochemotherapy on blastic spine metastases involving posterior walls of the lumbar vertebral bodies with epidural extension. These treatments were performed safely under cone beam computed tomography. Local tumor control was obtained on the subsequent follow-up as well as pain relief and disability improvement. Electrochemotherapy might be considered for patients with thus far no other alternative in order to obtain tumor control and improvement in patients' quality of life. [ABSTRACT FROM AUTHOR]

Fiberboards were manufactured from filled phenolic resins (lignin-formaldehyde or glyoxal) and petiole date palm fibers. Lignin was obtained from paper industry waste black liquor. To improve lignin reactivity and increase the bonding strength between matrix and fiber, phosphogypsum (PG) was used as a filler in the resin formulation from 1 to 3 wt%. Phosphogypsum exhibited excellent performance as binder; this was verified by a decrease in the gelation time and an increase in internal bond (IB) in fiberboards. The analysis confirmed that resin reactivity depends on aldehyde types (glyoxal or formaldehyde) and PG proportion. Most of the obtained boards were of good quality [modulus of elasticity (MOE) up to 1230 MPa; modulus of rupture (MOR) up to 25 MPa; internal bond (IB) up to 0.23 MPa; water absorption (WA) up to 28%]. [ABSTRACT FROM AUTHOR]

Different composites panels were prepared using two granulometrys of fibers from date palm petiole (PDPF) and bio-matrix from lignin-glyoxal-resin (LGR). The composites panels were manufactured at different PDPF percentages ranging from 10 to 70 wt%. Mechanical properties of the prepared samples were evaluated by measuring tensile strength, Young`s modulus and elongation. The obtained results showed that the sample made from fibers/thermo pressed resin 50/50 wt% has the best mechanical properties. The increase of the granulometry of the fibers from 250 to 500 µm results in an improvement of the tensile strength and Young`s modulus values. However, the LGR matrix reinforced with PDPF showed high values of water diffusion coefficient when compared to the unreinforced LGR. [ABSTRACT FROM AUTHOR]

Stable aqueous suspensions with high cellulosic contents and low fractions of lignin have been prepared from Cactus fibres via chemical delignification of the Cactus biomass feedstock with a sodium hydroxide–anthraquinone (soda–AQ) mixture. In order to optimize the reaction parameters, various temperatures between 120 and 170 °C and reaction times between 60 and 180 min were examined. The optimal yield of the resulting alkaline pulps (corresponding to the complete reaction of the raw materials) was equal to 41.4%, while the morphological parameters of individual cellulose fibres (such as length, width, and fraction of fine elements) were determined using a MorFi analyser. The estimated degree of polymerization, water retention value, total charge, and drainability of the produced pulps confirmed their suitability for papermaking applications; as a result, paper sheets were manually prepared using a Rapid-Köthen sheet former apparatus. The morphological analysis of the produced paper was conducted using a scanning electron microscopy technique, and its structural and mechanical properties were evaluated with the standard laboratory testing equipment. The obtained results indicate that the paper fabricated from Cactus fibres via the soda–AQ delignification process exhibits homogenous morphology as well as satisfactory mechanical and structural properties. [ABSTRACT FROM AUTHOR]

In this work, Tunisian Opuntia ficus- indica was used as a raw material for papermaking. Analysis of the chemical composition of this raw material has shown that the extractive substances are relatively high, since their content is in the range of 36, 24, 30 and 9.8 %, in cold and hot water, in a 1 % sodium hydroxide solution and in an ethanol-toluene mixture, respectively. The content of α-cellulose is high (53.6 %) compared to other non-woody plants. The low proportion of lignin (4.8 %) allowed us to propose a very soft delignification process using a soda-hydrogen peroxide process. The yield of the pulp obtained after mechanical defibration was significantly high (80.8 %) compared to other conventional pulping processes. Finally, the laboratory handmade standard sheets prepared have very good structural and mechanical properties. These results demonstrated the suitability of this plant for papermaking applications. In fact, excellent fibers were prepared using very soft cooking conditions and without bleaching treatment, and high-performance papers were made thereof without refining. [ABSTRACT FROM AUTHOR]

The brain-derived neurotrophic factor BDNF plays a critical role in neuronal development and the induction of L-LTP at glutamatergic synapses in several brain regions. However, the cellular and molecular mechanisms underlying these BDNF effects have not been firmly established. Using in vitro cultures of cortical neurons from knockout mice for Pld1 and Rsk2, BDNF was observed to induce a rapid RSK2-dependent activation of PLD and to stimulate BDNF ERK1/2-CREB and mTor-S6K signalling pathways, but these effects were greatly reduced in Pld1-/- neurons. Furthermore, phospho-CREB did not accumulate in the nucleus, whereas overexpression of PLD1 amplified the BDNF-dependent nuclear recruitment of phospho-ERK1/2 and phospho-CREB. This BDNF retrograde signalling was prevented in cells silenced for the scafolding protein PEA15, a protein which complexes with PLD1, ERK1/2, and RSK2 after BDNF treatment. Finally PLD1, ERK1/2, and RSK2 partially colocalized on endosomal structures, suggesting that these proteins are part of the molecular module responsible for BDNF signalling in cortical neurons. [ABSTRACT FROM AUTHOR]

Evidence has begun to emerge for microRNAs as regulators of synaptic signaling, specifically acting to control postsynaptic responsiveness during synaptic transmission. In this report, we provide evidence that Drosophila melanogaster miR-1000 acts presynaptically to regulate glutamate release at the synapse by controlling expression of the vesicular glutamate transporter (VGlut). Genetic deletion of miR-1000 led to elevated apoptosis in the brain as a result of glutamatergic excitotoxicity. The seed-similar miR-137 regulated VGluT2 expression in mouse neurons. These conserved miRNAs share a neuroprotective function in the brains of flies and mice. Drosophila miR-1000 showed activity-dependent expression, which might serve as a mechanism to allow neuronal activity to fine-tune the strength of excitatory synaptic transmission. [ABSTRACT FROM AUTHOR]

Background MR spectroscopy and diffusion-weighted imaging are useful non invasive imaging modalities used for characterization of different sellar and suprasellar lesions. Patient and methods We studied 30 cases of suprasellar SOLs (as proved by conventional MRI), MRS and DWI. Our findings were correlated with histopathological analysis after surgical resection. Results Three false positive cases in which cMRI give diagnosis mismatched with that obtained after adding the MRS findings and ADC values. MR spectrum type IIC is found in macroadenoma, craniopharyngioma, meningioma and germinoma with characteristic broad lipid peak in the second and forth types and elevated alanine peak in meningioma. Glioma had MRS appearance of type IIB. Simple differentiation between tumor types were achieved by the mean ADC values which were statistically significant (p < 0.001) when correlated to the histological diagnosis. When the ADC value of 0.6 x 10-3 mm²/s this strongly points to macroadenoma, ADC value of 1.05 x 10-3 mm²/s in meningiomas, ADC value 1.88 8 x 10-3 mm²/s strongly points to craniopharyngioma, while gliomas and germinoma had ADC values 1.6 x 10-3 mm²/s and 1.0 x 10-3 mm²/s respectively. Conclusion MR spectroscopy and DWMRI are considered important diagnostic tools complementary to cMRI in pre-surgical evaluation and discrimination between different sellar and suprasellar lesions. [ABSTRACT FROM AUTHOR]

Morphological studies of Chalaropsis punctulata and Thielaviopsis paradoxa revealed that the two fungi are similar to each other and produce endoconidia from phialidic conidiophores and thick dark-walled and pigmented aleuroconidia from conidiophores. There are minor morphological characters which separate the fungus Ch. punctulata from T. paradoxa: the latter form aleuroconidia in chains at the tip of specialized hyphae, whereas the former produce aleuroconidia singly. The percent inhibition of mycelial growth and the total count of conidia showed good inhibitory effects in all biocontrol methods used. The antagonist activity of Trichoderma harzianum against Ch. punctulata was due mainly to coil formation and hyphae grew alongside of the pathogen hyphae. Both hyphae and conidia of Ch. punctulata were malformed and swelled abnormally in the case of Bacillus isolates. This is the first report of Ch. punctulata on date palm in Egypt. [ABSTRACT FROM AUTHOR]

Coffin-Lowry syndrome (CLS) is a syndromic form of mental retardation caused by loss of function mutations in the X-linked RPS6KA3 gene, which encodes RSK2, a serine/threonine kinase acting in the MAPK/ERK pathway. The mouse invalidated for the Rps6ka3 ( Rsk2-KO) gene displays learning and long-term spatial memory deficits. In the current study, we compared hippocampal gene expression profiles from Rsk2-KO and normal littermate mice to identify changes in molecular pathways. Differential expression was observed for 100 genes encoding proteins acting in various biological pathways, including cell growth and proliferation, cell death and higher brain function. The twofold up-regulated gene ( Gria2) was of particular interest because it encodes the subunit GLUR2 of the AMPA glutamate receptor. AMPA receptors mediate most fast excitatory synaptic transmission in the central nervous system. We provide evidence that in the hippocampus of Rsk2-KO mice, expression of GLUR2 at the mRNA and at the protein levels is significantly increased, whereas basal AMPA receptor-mediated transmission in the hippocampus of Rsk2-KO mice is significantly decreased. This is the first time that such deregulations have been demonstrated in the mouse model of the Coffin-Lowry syndrome. Our findings suggest that a defect in AMPA neurotransmission and plasticity contribute to mental retardation in CLS patients. [ABSTRACT FROM AUTHOR]

Coffin-Lowry syndrome (CLS) is a syndromic form of X-linked mental retardation, characterized in male patients by psychomotor and growth retardation and various skeletal anomalies. CLS is caused by mutations in the RPS6KA3 gene, which encodes RSK2, a growth factor-regulated protein kinase. Cognitive deficiencies in CLS patients are prominent, but markedly variable in severity, even between siblings. However, the vast majority of patients are severely affected, with mental retardation ranging from moderate to profound. We used a RSK2-KO mouse model that shows no obvious brain abnormalities at the anatomical and histological levels to study the function of RSK2 in neurosecretion. Behavioral studies revealed normal motor coordination, but a profound retardation in spatial learning and a deficit in long-term spatial memory, providing evidence that RSK2 plays similar roles in mental functioning both in mice and human. We found that associative LTP at cortical inputs to the lateral amygdala was blocked in Rsk2 KO mice. Using an RNA interference rescue strategy in PC12 cells, we were able to demonstrate that RSK2 regulates catecholamine release through the phosphorylation of PLD. These results provide the first molecular evidence that RSK2 could regulate neurotransmitter release by activating PLD production of lipids required for exocytosis. [ABSTRACT FROM AUTHOR]

The article presents a study involving the characterization of poly(glycerol-sebacate) (PGS) in curing temperatures and durations. PGS is used for creating man-made microenvironments for tissue engineering and therapeutic applications. Its samples are acquired through curing the pre-polymer in a vacuum oven at 20 kilopascals. The results showed that PGS is an elastomer that is fully amorphous over 35 degrees Celsius.

Amphisomes are organelles of the autophagy pathway that result from the fusion of autophagosomes with late endosomes. While biogenesis of autophagosomes and late endosomes occurs continuously at axon terminals, non-degradative roles of autophagy at boutons are barely described. Here, we show that in neurons BDNF/TrkB traffick in amphisomes that signal locally at presynaptic boutons during retrograde transport to the soma. This is orchestrated by the Rap GTPase-activating (RapGAP) protein SIPA1L2, which connects TrkB amphisomes to a dynein motor. The autophagosomal protein LC3 regulates RapGAP activity of SIPA1L2 and controls retrograde trafficking and local signaling of TrkB. Following induction of presynaptic plasticity, amphisomes dissociate from dynein at boutons enabling local signaling and promoting transmitter release. Accordingly, sipa1l2 knockout mice show impaired BDNF-dependent presynaptic plasticity. Taken together, the data suggest that in hippocampal neurons, TrkB-signaling endosomes are in fact amphisomes that during retrograde transport have local signaling capacity in the context of presynaptic plasticity. There is growing evidence that autophagy might serve specialized functions in neurons besides its role in protein homeostasis. In this study, authors demonstrate that axonal retrograde transport of BDNF/TrkB in neuronal amphisomes is involved in plasticity-relevant local signaling at presynaptic boutons and that SIPA1L2, a member of the SIPA1L family of neuronal RapGAPs, associates via LC3b to TrkB-containing amphisomes to regulate its motility and signaling at the axon terminals [ABSTRACT FROM AUTHOR]

A correction to the article "Transcriptome profile reveals AMPA receptor dysfunction in the hippocampus of the Rsk2-knockout mice, an animal model of Coffin-Lowry syndrome" that was published in the 2010 issue is presented.

Selective, sensitive, easy, and fast voltammetric techniques were developed for the analysis of Hydroxychloroquine (HCQ). These analysis were carried out at sodium dodecyl sulphate modified carbon nanotube paste electrode (SDSMCNTPE) using an aqueous 0.2 M phosphate buffer solution as supporting electrolyte. The field emission-scanning electron microscopy, cyclic voltammetry (CV), and electrochemical impedance spectroscopy were used for material characterization. A minute quantity of the SDS surfactant was sufficient to convey an outstanding electrocatalytic action to the electrochemical oxidation nature of HCQ. The HCQ molecule parades only electrochemical oxidation (irreversible) with the transfer of two electrons. The detection of HCQ was carried out through CV method at SDSMCNTPE and bare carbon nanotube paste electrode (BCNTPE). The corresponding analytical curve offered a decent linear nature in the considered HCQ concentration range (10–40 µM) and the detection limit was found to be 0.85 µM. The significant peak to peak split-up was observed between HCQ and interferents with a decent sensitivity and stability. The SDSMCNTPE to be an approachable electrode for the usage in the examination of HCQ independently and in the presence of paracetamol (PC) and ascorbic acid (AA). Thus, they were used to determine HCQ in pharmaceutical formulations and the results that showed good agreement with comparative methods. Furthermore, a mechanism for HCQ electro-oxidation was proposed. [ABSTRACT FROM AUTHOR]

Diclofenac (DCF) is a non-steroidal anti-inflammatory drug used for the treatment of different diseases such as rheumatoid arthritis, spondylitis, arthritis and sport injuries. Increased use of DCF has initiated a significant worry regarding their presence in the environment. This study reports a sensitive and selective electrochemical sensing platform based on poly glycine modified carbon nanotube paste electrode (PGMCNTPE) for the simultaneous determination of DCF and dopamine (DA) by differential pulse voltammetry (DPV). The characterisation techniques like cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) accomplished in 1 mM K4 [Fe (CN)6], displays that the electroactive surface area of PGMCNTPE is augmented and the charge-transfer resistance is diminished in comparison to the bare carbon nanotube paste electrode (BCNTPE). Various parameters responsible for the peak improvement such as accumulation time, accumulation potential, pH and number of polymerisation cycles were optimised. Scan rate studies done by CV technique reveals that the process is irreversible and adsorption controlled in 0.2 M solution of phosphate buffer (PBS). The deposition of the poly glycine film on the BCNTPE surface enhanced the sensors electronic transfer rate, which reveals a heterogeneous rate constant (k0) of 3.13 × 10–3 s−1. PGMCNTPE shows two linear ranges with an increase in DCF concentration from 4 to 100 μM and a detection limit calculated by considering second linear range was found to be 0.21 μM. The selectivity of PGMCNTPE towards DCF was investigated in the existence of various interfering molecules and inorganic metal ions with fivefold higher concentration. The pertinence of the proposed sensor was analysed by quantification of DCF in pharmaceutical samples. The prepared sensor exhibits a virtuous performance in detection of DCF due to excellent repeatability, reproducibility and stability. [ABSTRACT FROM AUTHOR]