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Abstract Background The downfall of formocresol as a pulpotomy medicament highlights the importance of cytotoxic evaluation and the establishment of a safe concentration of dental material prior to its usage in the oral cavity. Uncaria gambir is an herbal plant that possesses antimicrobial, anti-inflammatory and antioxidant properties, suggesting its potential as an alternative medicament for pulpotomy. However, there are not many studies published on its cytotoxicity, with some using non-standardised techniques and reported variable outcomes. Here, we investigated the concentration and time-dependent toxicity of Uncaria gambir extract towards the M3CT3-E1 cell line and compared it with the gold standard pulpotomy medicament: mineral trioxide aggregate (MTA). Methods Uncaria gambir extracts at concentrations ranging from 1000 to 7.8 µg/ml and MTA eluates at 4- and 48 h setting times were prepared. 10% dimethyl sulfoxide (DMSO) and culture media were used as positive and negative controls respectively. Cell viability on days 1, 2, 3 and 7 was analysed using Alamar Blue and Live and Dead Cell assay. Any morphological cellular changes were evaluated using transmission electron microscopes (TEM). Data were analysed using a two-way mixed Analysis of Variance (ANOVA). Results The interaction between the concentration and exposure time on the fluorescence intensity of Uncaria gambir extract and MTA 48 h was found to be statistically significant (p < 0.001). No cytotoxic effects on the cells were exerted by both MTA 48 h and Uncaria gambir extract at a concentration below 500 µg/mL. TEM analysis and Live and Dead Cell assay for both materials were comparable to the negative control. No significant differences in fluorescent intensity were observed between Uncaria gambir extract at 500 µg/mL and MTA 48 h (p > 0.05). Conclusion Uncaria gambir extracts at a maximum concentration of 500 μg/mL are non-cytotoxic over time and are comparable to the MTA.

Augmentative exoskeletons (AEs) are wearable orthotic devices that, when coupled with a healthy individual, can significantly enhance endurance, speed, and strength. Exoskeletons are function-specific and individual-specific, with a multitude of possible configurations and joint mechanisms. This complexity presents a challenging scenario to quantitatively determine the optimal choice of the kinematic configuration of the exoskeleton for the intended activity. A comprehensive simulation-based framework for obtaining an optimal configuration of a passive augmentative exoskeleton for backpack load carriage during walking is the theme of this research paper. A musculoskeletal-based simulation approach on 16 possible kinematic configurations with different Degrees of Freedom (DoF) at the exoskeleton structure’s hip, knee, and ankle joints was performed, and a configuration with three DoF at the hip, one DoF at the knee, three DoF at the ankle was quantitatively chosen. The Root Mean Square of Deviations (RMSD) and Maximum Deviations (MaxDev) between the kinematically coupled human–exoskeleton system were used as criteria along with the Cumulative Weight Score (CWS). The chosen configuration from the simulation was designed, realised, and experimentally validated. The error of the joint angles between the simulation and experiments with the chosen configuration was less than 3° at the hip and ankle joints and less than 6° at the knee joints.

Untreated and alkali-treated (5% NaOH) Chloris barbata flower fibers (CBFFs) were used to fabricate the composites by hand lay-up method. Novel composite plates were manufactured by changing fiber weight fraction (5 wt.%, 10 wt.%, 15 wt.%, 20 wt.%, and 25 wt.%), raw and 5% NaOH treated fibers. The impact of NaOH treatment and fiber weight fraction on tensile, flexural, impact, morphological, and thermal properties of CBFF reinforced epoxy composites were examined and reported for the first time in this article. The tensile, flexural, and impact properties of the composites were increased up to 20 wt. % fiber additions and after that dropped. After the tensile testing, broken cross-sections of the composites were analyzed by scanning electron microscopy (SEM), which showed that NaOH treated CBFF reinforced composite has better interfacial bonding and lesser voids. Thermogravimetric analysis (TGA), Fourier transform infrared analysis (FTIR), and Atomic force microscope (AFM) analysis of composites also pointed out that alkali-treated CBFF is a suitable material for reinforcement with the epoxy polymer matrix.

Land use and Land cover classification plays a vital role in understanding the changes happening on the surface of the earth. Vegetation classification can be performed by incorporating various deep learning models using Convolution Neural Network approach. The primary purpose of this research is to test the performances of pre-existing Deep Convolution Neural Network (CNN) models for vegetation classification in the Jupiter Inlet Lighthouse Outstanding Natural Area (JILONA). Specifically, this study focuses on examining of the capacity of Scene and Pixel classification technique using certain 3 band and 5 band combinations. Eight well known scene-based deep convnets, namely VGG19, ResNet152V2, InceptionV3, EfficientNetB5, Xception, InceptionResNetV2, MobileNetV2, DenseNet201, and one important pixel classification model, UNet have been used for vegetation mapping in the North and South part of the JILONA. Among all the scene classification models, EfficientNetB5 and DenseNet201 outperformed all other models with an accuracy of over 97%. Xception and ResNet152V2 model exhibited 95% accuracy, whereas the accuracy of remaining models ranged from 85% to 92%. The classification map achieved through UNet pixel-based method, resulted with an accuracy of about 87% and an even better 91% when all 5 bands (Blue, Green, Red, RedEdge, Near-infrared) were used for training.

The physicochemical, thermal, and surface morphological properties of the Sida mysorensis fiber (SMF) were investigated first time in this article. From the chemical compositional analysis, higher cellulose (53.36 wt. %) and lower hemicelluloses (15.23 wt. %), lignin (9.46 wt. %), wax (0.86 wt), and ash content of (3.33 wt. %) SMF were acknowledged. The different functional groups of SMF were determined through the Fourier transform infrared spectrometer. The Crystallinity index (41.17%) and crystalline size (13.06 nm) of SMF were evidenced through the X-ray diffraction analysis. Atomic force microscopy investigation was used to study the surface morphology of SMF. Thermal stability (220°C) and kinetic activation energy (65.486 KJ/mol) of the SMF were determined through the thermogravimetric analysis. All the above findings ensured that SMF can be used as reinforcement in polymer composite.

Concerns have been raised about the usage of sodium hypochlorite (NaOCl) in endodontics following its toxic effects. Effective ecoproduce (EEP), an organic solution produced through the fermentation of fruit peels, exhibits antibacterial and antibiofilm action, suggesting its potential as an endodontic irrigant. However, studies on its cytotoxicity are limited. This in vitro study aimed to evaluate the cytotoxic effects of EEP at different concentrations and fermentation periods against the MC3T3-E1 cell. EEP derived from orange and pineapple peel waste and fermented for 3 and 6 months was prepared from 100% to 0.78% concentration. Briefly, 2.5% NaOCl was used as the comparison group. Cell viability was analysed using Alamar Blue and Live and Dead Cell assay. A transmission electron microscope (TEM) was used to evaluate ultrastructural changes to the cells. Data analysis was performed using a two-way mixed Analysis of Variance (ANOVA). EEP exhibited concentration-dependent cytotoxicity regardless of the fermentation period (p > 0.05). A concentration below 6.25% was non-cytotoxic and comparable to the negative control (p > 0.05). Live and Dead Cell assay and TEM analysis complement the findings. The mean cell viability of EEP at all concentrations for both fermentation periods was significantly higher than that of 2.5% NaOCl (p < 0.05). Conclusively, 6.25% EEP fermented for 3 and 6 months are non-cytotoxic and can serve as an alternative endodontic irrigants.

Abstract Detection of nitroaromatics employing greener techniques has been one of the most active research fields in chemistry. A series of triphenylamine (TPA) functionalized carboxylic acids were synthesized and characterized using various spectroscopic techniques including single-crystal X-ray diffraction analysis. The interaction of carboxylic acid-decorated TPAs with nitroaromatic compounds was photophysically explored using absorption and emission spectroscopy. Stern–Volmer plot accounts for the appreciable quenching constant of the TPA-acids. Density functional theory calculations were carried out to study the new compounds' frontier molecular orbital energy levels and the possible interactions with picrate anion and revealed an unusual charge transfer interaction between acids and picrate anion. The contact mode detection shows the TPA-acids can be used as dip-strip sensors for picric acid detection.

A topological index is a number that is connected to a chemical composition in order to correlate a substance’s chemical makeup with different physical characteristics, chemical reactivity, or biological activity. It is common to model drugs and other chemical substances as different forms, trees, and graphs. Certain physico-chemical features of chemical substances correlate better with degree-based topological invariants. Predictions concerning the dynamics of the continuing pandemic may be made with the use of the graphic theoretical approaches given here. In Networks, the degree entropy of the epidemic and related trees was computed. It highlights the essay’s originality while also implying that this piece has improved upon prior literature-based realizations. In this paper, we study an important degree-based invariant known as the inverse sum indeg invariant for a variety of graphs of biological interest networks, including the corona product of some interesting classes of graphs and the pandemic tree network, curtain tree network, and Cayley tree network. We also examine the inverse sum indeg invariant features for the molecular graphs that represent the molecules in the bicyclic chemical graphs.

The stability of a controlled network temperature control system (heat exchanger system) is examined in this study paper. A heat exchanger system keeps the end temperature of a liquid within defined parameters. The study proposes a linearized model of a temperature control system based on a delay-dependent state equation to accomplish this job. For a temperature management system in a network having time-varying delays, the LK functional (Lyapunov–Krasovskii) method is coupled with the reciprocal convex lemma. To get less conservative stability requirements, a new LK functional was assumed in the stability analysis, and the time-dependent of the (LK) functional was taken via the reciprocal convex combination approach. Finally, under the LMI (linear matrix inequalities) paradigm, the suggested stability analysis leads to a stability criterion. The suggested results establish a new stability criterion for a more accurate operating form for a present temperature control system based on a theoretically obtained temperature management system.

Castor is an important non edible oil seed crop cultivated throughout the world in varied climatic situation, due to its wider adaptability. Genetic diversity plays a foremost role in developing a potent genotype. Hence the present study was attempted to group 68 castor genotypes into different clusters based on Mahalanobis D2 statistics. Based on genetic distance, 68 castor genotypes were grouped into 14 clusters. Among the 11 biometrical characters studied, seed yield per plant has contributed more to the total divergence. The maximum intra cluster distance was observed in cluster XIV and minimal intra cluster distance was recorded in cluster II. Similarly maximum inter cluster distance was observed between cluster XIII and cluster XIV. The minimal inter cluster distance was observed between cluster III and cluster V. Thus the selection of genotypes from these diverse clusters will help us to arrive at potent segregants in future hybridization programme.

The correction of rotated malpositioned tooth/teeth into the dental arch alignment in the mixed-dentition is often a challenging task for paediatric dentists. Failure in addressing this issue can bring about detrimental effect to the developing dentition and increases the probability of a complex orthodontic treatment in later years. Factors such as severity of the malpositioned teeth, patient’s treatment compliance, limitation in specific functions of the selected appliance, availability of bone and space may dictate the success of the treatment. The combined use of a simple sectional orthodontic wire appliance and a 2×4 orthodontic appliance has been shown to produce a positive effect. The appliances resulted in derotation of the rotated malpositioned teeth and bringing them into arch alignment in two cases. This treatment option had eliminated the detrimental effects to the developing dentition and helped patients to enhance their smile and dental aesthetics.

Abstract Advanced structural characterisation techniques which are rapid to use, non-destructive and structurally definitive on the nanoscale are in demand, especially for a detailed understanding of extended-defects and their influence on the properties of materials. We have applied the electron backscatter diffraction (EBSD) technique in a scanning electron microscope to non-destructively characterise and quantify antiphase domains (APDs) in GaP thin films grown on different (001) Si substrates with different offcuts. We were able to image and quantify APDs by relating the asymmetrical intensity distributions observed in the EBSD patterns acquired experimentally and comparing the same with the dynamical electron diffraction simulations. Additionally mean angular error maps were also plotted using automated cross-correlation based approaches to image APDs. Samples grown on substrates with a 4° offcut from the [110] do not show any APDs, whereas samples grown on the exactly oriented substrates contain APDs. The procedures described in our work can be adopted for characterising a wide range of other material systems possessing non-centrosymmetric point groups.

Two-dimensional analytical model of symmetric halo doped double gate tunnel field effect transistor has been presented in this work. This model is developed based on the 2-D Poisson’s equation. Some important parameters such that surface potential, vertical and lateral electric field, electric field intensity and band energy have been modelled. The doping concentration and length of halo regions are varied and dependency of various parameters is studied. The halo doping is imparted to improve the ON current and to reduce the intrinsic ambipolarity of the device. Hence we can achieve improved ION/IOFF ratio. The scaling property of halo doped structure is analyzed with various dielectric constants.

Complicated crown-root fractures account for a small percentage of traumatic dental injuries seen in children; however, management of these injuries can be very challenging to clinicians. Factors such as complexity of the injury, patient’s age and dentition stage, patient’s cooperation, and parental demands may have some bearing on the type of treatment undertaken and its outcomes. In some children, these injuries may have significant impact on their quality of life. The purpose of this article is to describe two cases of complicated crown-root fracture which were successfully managed through orthodontic extrusion using a sectional fixed orthodontic technique. The basis for the treatment technique and its favourable outcomes were highlighted with its advantages and drawbacks.

Dens evaginatus is a dental developmental anomaly that arises due to the folding of the inner dental epithelium that leads to the formation of an additional cusp or tubercle on the occlusal surface of the affected tooth. This accessory tissue projection may carry with it a narrow and constricted pulp horn extension. Occasionally, the tubercle easily fractures, thus leading to microexposure of the pulp horn and eventual pulp necrosis. Often, the pulp necrosis occurs at a time the root development of the affected tooth is incomplete. Apexification with calcium hydroxide and mineral trioxide aggregates has been the mainstay of treatment options before root canal obturation in immature nonvital permanent teeth. Lately, regenerative endodontics (maturogenesis) is becoming one of the preferred treatment modalities to manage such teeth. The current case highlights the possibility of a bioceramic material (EndoSequence Root Repair Material, BC RRM-Fast Set Putty™, Brasseler, USA) which supposed to provide apical root closure (apexification) and could also induce continuation of root growth (maturogenesis).

Anterior crossbite is relatively a common presentation in the mixed dentition stage. If left untreated, it can lead to a host of problems and may complicate future orthodontic treatment. One of the major difficulties in performing anterior crossbite correction in young children is treatment compliance. In most cases, poor compliance is due to the unacceptability of the removable appliance used. This article describes three cases of successful correction of anterior crossbite of patients in mixed dentition using short-span wire-fixed orthodontic appliances. This sectional appliance provides an alternative method of correcting anterior crossbite of dental origin and offers many advantages compared to the use of removable appliances.

Current-voltage (I-V) measurements combined with analytical calculations have been used to explain mechanisms for forward-bias current flow in Copper (Cu) Schottky diodes fabricated on Gallium Nitride (GaN) epitaxial films. An ideality factor of 1.7 was found at room temperature (RT), which indicated deviation from thermionic emission (TE) mechanism for current flow in the Schottky diode. Instead the current transport was better explained using the thermionic field-emission (TFE) mechanism. A high barrier height of 1.19 eV was obtained at room temperature. X-ray photoelectron spectroscopy (XPS) was used to investigate the plausible reason for observing Schottky barrier height (SBH) that is significantly higher than as predicted by the Schottky-Mott model for Cu/GaN diodes. XPS measurements revealed the presence of an ultrathin cuprous oxide (Cu2O) layer at the interface between Cu and GaN. With Cu2O acting as a degenerate p-type semiconductor with high work function of 5.36 eV, a high barrier height of 1.19 eV is obtained for the Cu/Cu2O/GaN Schottky diode. Moreover, the ideality factor and barrier height were found to be temperature dependent, implying spatial inhomogeneity of barrier height at the metal semiconductor interface.

Optical absorption spectra of KBr:Tl+ (0.0125 mol%) single crystals shows A, B and C bands around 258, 220 and 210 nm respectively. In KCl0.1Br0.9 :Tl+ (0.0125 mol%) mixed crystals exhibit slightly broadening of the A-band towards lower wavelength side. The broadening of the absorption spectra are suggested to be due to some complex Tl+ centers involving Br- and Cl- ions formed in the mixed crystals. When excited at A, B and C-bands of Tl+ ions, PL of KBr:Tl+ showed emission band around 320 with a prominent shoulder around 365 nm. In KCl0.1Br0.9 mixed crystals the shoulder around 365 nm is not prominent due to the perturbing influence of Cl- ions. Addition bands in the excitation spectra are attributed to the presence of Tl+ dimmers. PSL observed in X-ray irradiated crystals resembled their respective PL emissions indicating that PSL in them is due to Tl+ ions.

In the title compound, C18H15NO2, the dihedral angle between the mean planes of the quinoline ring system and the phenyl ring is 78.8 (1)°. The mean plane of the carboxylate group is twisted from the mean planes of the quinoline ring system and phenyl ring by 1.5 (9) and 77.6 (4)°, respectively. In the crystal, molecules are linked by weak C—H...O interactions, generating C(8) chains along [001]. Weak π–π stacking interactions are also observed [centroid–centroid separation = 3.6238 (12) Å].

In the title compound, C20H25NO2, the cyclohexyl ring adopts a slightly disordered chair conformation. The dihedral angle between the mean planes of the quinoline ring and the carboxylate group is 22.2 (6)°. In the crystal, weak C—H...N interactions make chains along [010].

In the title compound, C16H10ClNO2, the dihedral angle between the quinoline ring system and the benzene ring is 14.7 (5)°. The carboxylate group is twisted from the mean planes of the quinoline ring system and the benzene ring by 17.7 (5) and 32.1 (4)°, respectively. In the crystal, inversion dimers are formed with the molecules linked by pairs of weak C—H...O interactions arising from an activated aromatic C atom adjacent to the C—Cl bond, generating R22(14) loops.

In the title compound, C18H15NO2, the dihedral angle between the mean planes of the quinoline ring system and the phenyl ring is 48.1 (5)°. The mean plane of the carboxylate group is twisted from the mean planes of the latter by 19.8 (8) and 64.9 (5)°, respectively. The crystal packing features weak C—H...O interactions, which form chains along [010].

In the title compound, C17H12ClNO2, the dihedral angle between the mean planes of the quinoline ring system and the benzene ring is 68.7 (7)°. The mean plane of the carboxylate group is twisted from the latter planes by 14.0 (1) and 80.2 (4)°, respectively. In the crystal, weak C—H...O interactions are observed, forming chains along [001]. In addition, π–π stacking interactions [centroid–centroid distances = 3.8343 (13) and 3.7372 (13)Å] occur. No classical hydrogen bonds were observed.

Tooth avulsion is a dental emergency that needs prompt treatment to minimise complications. This study aims to evaluate the knowledge and awareness of avulsed tooth management among dental surgery assistants at the UKM Dental Polyclinic. This survey research design of a 19- item questionnaire was distributed to 59 dental surgery assistants (DSAs). The questionnaire consisted of demographic profile questions and questions regarding awareness and knowledge of tooth avulsion and its immediate management. The results showed that 78% of DSAs at the Institute know about first aid management of avulsed teeth, with the majority being taught during their training course. Moreover, 96.2% of the DSAs know what tooth avulsion is and recognise it as a dental emergency. Although 75% of the DSAs have never previously handled any avulsed tooth case, 50% are confident in advising the public on what to do with an avulsed tooth at the time of injury. As for the specific management questions of an avulsed tooth, the responses from the DSAs varied according to the questions, ranging from 50% to 85%. DSAs at the Institute have varying levels of awareness and knowledge regarding tooth avulsion. Therefore, regular education programmes on dental trauma and its management will help improve the DSAs’ current knowledge and ability to manage avulsion injuries better in emergencies. [ABSTRACT FROM AUTHOR]