Original Structural Features Research Articles

Chemical characterization of polysaccharides from Gracilaria gracilis from Bizerte (Tunisia)

Polysaccharides were extracted from Gracilaria gracilis collected from Manzel Jemil Lake in Bizerte Tunisia, with two different solvents (water and NaOH 0.3 M). Different assays were performed on samples (total sugars, neutral sugars, uronic acids, anhydrogalactose, proteins, sulphates, pyruvates), followed by high performance anion-exchange chromatography (HPAEC) to observe the monosaccharide composition, high pressure size exclusion chromatography with multi-angle laser light scattering (HPSEC-MALS) to obtain the molecular mass, Fourier transform infrared spectroscopy (FTIR), and 1D and 2D nuclear magnetic resonance (NMR) to access to structural data. Results have shown that the polysaccharide extracted from Gracilaria gracilis collected from Manzel Jemil Lake in Bizerte Tunisia, is of agar type but with high molecular mass and some original structural features. Hence, the sample was found to contain 9 % of pyruvate groups and is partly sulphated at the C4 of β-d-galactose and methylated on C2 of anhydro-α-l-galactose. The polymer from G. gracilis from Bizerte thus presents a never described structure that could be interesting for further rheological or biological activities applications.

HDGCN: Dual-Channel Graph Convolutional Network With Higher-Order Information for Robust Feature Learning

Graph convolutional network (GCN) algorithms have been employed to learn graph embedding due to its inductive inference property, which is extended to GCN with higher-order information. However, the application of these higher-order information is confusing and not effectively distinguished. In addition, single channel GCN using higher-order information is weak for robust feature learning, and existing dual-channel GCNs rarely take higher-order information into account. To alleviate the above problems, we propose a dual-channel GCN with higher-order information for robust feature learning, denoted as HDGCN. Firstly, features of positive and negative higher-order graphs are extracted that fully exploits the self-contained attributes and higher-order geometric information. Meantime, the features of original graph structure are extracted by a conventional GCN that utilizes the self-contained feature attributes. Then, node features are represented as edge features by a feature fusion function. For the selection of negative samples, a fractional staggered negative sampling method is applied, by which the trainable graph model gains better topological features. Finally, the performance on seven real-world datasets demonstrates that HDGCN obtains the state-of-the-art performance on pairwise link prediction, higher-order structure prediction, and node classification tasks. By changing the attributes of multiple tasks, it can be proved that HDGCN has good robustness.

Quantitative analysis of deep learning-based denoising model efficacy on optical coherence tomography images with different noise levels

BackgroundTo quantitatively evaluate the effectiveness of the Noise2Noise (N2N) model, a deep learning (DL)-based noise reduction algorithm, on enhanced depth imaging-optical coherence tomography (EDI-OCT) images with different noise levels. MethodsThe study included 30 subfoveal EDI-OCT images averaged with 100 frames from 30 healthy participants. Artificial Gaussian noise at 25.00, 50.00, and 75.00 standard deviations were added to the averaged (original) images, and the images were grouped as 25N, 50N, and 75N. Afterward, noise-added images were denoised with the N2N model and grouped as 25dN, 50dN, and 75dN, according to previous noise levels. The choroidal vascularity index (CVI) and deep choroidal contrast-to-noise ratio (CNR) were calculated for all images, and noise-added and denoised images were compared with the original images. The structural similarity of the noise-added and denoised images to the original images was assessed by the Multi-Scale Structural Similarity Index (MS-SSI). ResultsThe CVI and CNR parameters of the original images (68.08 ± 2.47 %, and 9.71 ± 2.80) did not differ from the only 25dN images (67.97 ± 2.34 % and 8.50 ± 2.43) (p:1.000, and p:0.062, respectively). Noise reduction improved the MS-SSI at each noise level (p < 0.001). However, the highest MS-SSI was achieved in 25dN images. ConclusionsThe DL-based N2N denoising model can be used effectively for images with low noise levels, but at increasing noise levels, this model may be insufficient to provide both the original structural features of the choroid and structural similarity to the original image.

Visual Tracking based on deformable Transformer and spatiotemporal information

At present, the Transformer-based Siamese network visual tracking method has shown strong influence and achieved remarkable results on various experimental sets. Especially on the premise of training on large-scale datasets, attention-based Transformer structures have been widely used. However, many trackers ignore the fusion enhancement of local and global features, and lack the extraction of spatiotemporal information. At the same time, the original Transformer structural features are redundant and will be affected by irrelevant parts beyond the region of interest. To address these issues, we propose a new method (DTS) based on deformable Transformer and spatiotemporal information. As a Siamese structure, it contains multiple modules. The template frame gets local to global important features through 2D CNN and Self-Attention. The search frame gets spatiotemporal information of interest through 3D CNN and SFM and DAM and then uses Cross-Attention to establish the correlation between them, and finally predict the bounding box of the target through the corner points. In order to verify the effectiveness of our method, we conduct experiments on the LaSOT, GOT-10K, TrackingNet, VOT2018, OTB100 and VAU123 benchmark datasets, the result index is 2%–3% higher than the baseline method. The model structure is simplified without affecting the performance, and the FPS reaches 50. The results show that our proposed tracker is very competitive compared with other state-of-the-art methods.

A comprehensive proposal for rehabilitation of historic Armenian church belonging to 16th century AD (Diyarbakır, Turkey)

This study presents a comprehensive proposal for the rehabilitation of the ruined Surp Sargis Church located inside the historical city walls of Diyarbakır, namely the Suriçi region. The Suriçi region was home to many ancient civilizations and cultures. This study consists of four major stages; historical research, determination of the original structural features, seismic performance assessment, and a comprehensive proposal for the rehabilitation of the building. In the first stage, the history of the church, from its construction date to the present was examined based on the historical documents, common typology of the period, and old photographs. In the second stage, the plan, facade characteristics, construction system, and material properties of the existing structure were determined and reasons for the deterioration were identified. To determine the architectural features of the analyzed church, other Armenian churches dating back to the 16th century were evaluated in addition to the examination of the old plans, photographs, and repairs. Then, in the third stage, a seismic risk assessment of the church was done through linear, pushover, and kinematic limit analyses. In the final stage, a rehabilitation proposal was presented evaluating all the data obtained from previous stages. The proposed rehabilitation practice also considered local people living around this structure. The main goal of this study is to turn this structure into an active church for religious tourism activities where Armenians living in other places can attend worship and meetings at certain times of the year. Moreover, a social activity area for local people in the surrounding region was also planned. Accordingly, the current paper provides a comprehensive rehabilitation approach that can be applied to similar cultural heritage structures.

Low Friction of Graphene Oxide Aggregates in Lubricant Oil between a Steel Ball and Glass Disk under Boundary Lubrication.

Previously, isolated nanocarbons in lubricating oils were considered essential for good lubrication. However, we observed that graphene oxide (GO) aggregates in lubricating oil have lower frictional properties than isolated dispersed GO. The GO was dispersed in polyα-olefin (PAO) using alkylamine at different ratios of GO and alkylamine, or it was heated at different temperatures to synthesize high- and low-dispersible GO-dispersed PAO. X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and Raman spectroscopy measurements showed that low-dispersible modified GOs retained many of the original GO chemical and structural features. Macrotribological tests between a steel ball and glass disk in GO-dispersed oil were conducted with a load of 5 N under boundary lubrication. The friction interface was observed in situ using an optical microscope. In the low-dispersible GO-dispersed PAO, many GO aggregates were observed through optical microscopy. Surprisingly, the friction coefficients decreased when the GO aggregates entered the friction interface and covered the contact area. The low-dispersible GO-dispersed PAO using alkylamine had the lowest friction coefficient of 0.05, as the GO aggregates covered the contact area. From microtribological tests with a load of 0.8 mN as well, it is assumed that the low friction of the GO aggregates originates due to the sliding between the weakest shear layers in the aligned multiple GO layers.

Influence of the Carbon and Nitrogen Sources on Diabolican Production by the Marine Vibrio diabolicus Strain CNCM I-1629.

Recent advances in glycobiotechnology show that bacterial exopolysaccharides (EPS) presenting glycosaminoglycan (GAG)-like properties can provide a valuable source of bio-active macromolecules for industrial applications. The HE800 EPS, named diabolican, is a marine-derived anionic high-molecular-weight polysaccharide produced by Vibrio diabolicus CNCM I-1629 which displays original structural features close to those of hyaluronic acid. We investigated the impact of carbon and nitrogen substrates on both Vibrio diabolicus growth and diabolican production. Both substrates were screened by a one-factor-at-a-time method, and experimental designs were used to study the effect of glucose, mannitol, and ammonium acetate various concentrations. Results showed that the medium composition affected not only the bacterium growth and EPS yield, but also the EPS molecular weight (MW). EPS yields of 563 and 330 mg L−1 were obtained in the presence of 69.3 g L−1 glucose and 24.6 g L−1 mannitol, respectively, both for 116.6 mM ammonium acetate. MW was the highest, with 69.3 g L−1 glucose and 101.9 mM ammonium acetate (2.3 × 106 g mol−1). In parallel, the bacterial maximum specific growth rate was higher when both carbon and nitrogen substrate concentrations were low. This work paves the way for the optimization of marine exopolysaccharide production of great interest in the fields of human health and cosmetics.

CURRENT TRENDS IN THE RECONSTRUCTION OF INDUSTRIAL BUILDINGS FOR HOTEL FACILITIES ON THE EXAMPLE OF СHINA

The paper studies the conversion of industrial buildings into hotels. The main periods for adaptive reuse of industrial buildings into hotels are determined, the characteristics of repurposed industrial buildings into hotels are considered, and the tendencies of such renovations are determined both by the experience around the world and national situations in China. The advantages and problems of repurposing industrial buildings into hotels are revealed, compared with new developments, as well as with other aspects of reusing industrial buildings. Based on the analysis, recommendations are proposed on the directions of such conversion.&#x0D; Based on the generalization of the processes of the adaptive reuse of industrial buildings into hotels in China, the main stages of their formation are identified: 1st Period – driven by market economy (1990-2003); 2nd Period - rapid spread phase (2009-2014); 3rd Stage - phase of in-depth research (since 2015).&#x0D; In comparison with new construction, the advantages of adaptive reuse are more cost-effective, which takes less time, preserves monuments of industrial architecture, activates surrounding economies, which leads to energy saving, protects the environment, and ensures sustainable development of territories&#x0D; The challenges and risks that arise during such renovations are systematized, identifying the main fields of research.&#x0D; This study shows that there are several trends in repurposing industrial buildings. Firstly, market and economic issues still matter, while preservation of culture and environment is taking a more important role. Secondly, saving the individuality and basic characteristics of old industrial buildings with the integration of modern elements is important to ensure sustainable development. Thirdly, modern technologies are more popular than before. Lastly, the original spatial, structural and external features of abandoned and destroyed industrial buildings are preserved at maximum to be converted into new functions.

A proposal for the reconstruction of a historical masonry building constructed in Ottoman Era (Istanbul)

The present study includes a reconstruction proposal based on the original architectural and structural features of a historical masonry barrack building, which was built as a military barracks in 1866 and then demolished in the last 1940s. The building under the investigation is one of the first structures, in the historical peninsula, constructed by using industrial bricks in the Ottoman period. The study comprises of two stages, namely, the determination of the original architectural and structural features, as well as the historical process research focused on the building. The process from the date that the building was built to the time in which it was demolished was surveyed through historical documents and old photographs. In the second stage, georadar and electromagnetic field measurements were performed to determine whether archaeological remains exist in the area where the building is located. Evaluating the data obtained from the first two stages, floor plans, facade views, construction type, and material properties of the building were determined. The presented procedure in the study can be used as a reconstruction approach of the partly or completely demolished historical masonry buildings.

Saliency Detection via the Improved Hierarchical Principal Component Analysis Method

Aiming at the problems of intensive background noise, low accuracy, and high computational complexity of the current significant object detection methods, the visual saliency detection algorithm based on Hierarchical Principal Component Analysis (HPCA) has been proposed in the paper. Firstly, the original RGB image has been converted to a grayscale image, and the original grayscale image has been divided into eight layers by the bit surface stratification technique. Each image layer contains significant object information matching the layer image features. Secondly, taking the color structure of the original image as the reference image, the grayscale image is reassigned by the grayscale color conversion method, so that the layered image not only reflects the original structural features but also effectively preserves the color feature of the original image. Thirdly, the Principal Component Analysis (PCA) has been performed on the layered image to obtain the structural difference characteristics and color difference characteristics of each layer of the image in the principal component direction. Fourthly, two features are integrated to get the saliency map with high robustness and to further refine our results; the known priors have been incorporated on image organization, which can place the subject of the photograph near the center of the image. Finally, the entropy calculation has been used to determine the optimal image from the layered saliency map; the optimal map has the least background information and most prominently saliency objects than others. The object detection results of the proposed model are closer to the ground truth and take advantages of performance parameters including precision rate (PRE), recall rate (REC), and F-measure (FME). The HPCA model’s conclusion can obviously reduce the interference of redundant information and effectively separate the saliency object from the background. At the same time, it had more improved detection accuracy than others.

High Cycle Fatigue Performance of Inconel 718 Alloys with Different Strengths at Room Temperature

In this paper, the high cycle fatigue performance of solid solution state and aged Inconel 718 superalloys was studied at room temperature. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to analyze the original structural features and fatigue deformation features of two kinds of alloys. SEM, laser scanning confocal microscopy, and electron backscatter diffraction (EBSD) were used to analyze the secondary fracture features of the fatigue fracture morphology and fatigue fracture profile. The results showed that the aging treatment significantly affected the strength and plasticity of the alloy, which in turn affected the fatigue performance of the alloy. After the aging treatment, the yield strength σs and the tensile strength σb of the Inconel 718 alloy increased by 152% and 65.9%, respectively, compared with those of the solid solution state, but the rate of elongation δ and rate of contraction in the cross-section area φ decreased by 63.7% and 52.3%, respectively. The fatigue limit of the aged state was lower than that of the solid solution state by 6.3%. The quadratic function relationship between the high cycle fatigue limit σ−1 and the tensile strength σb of the Inconel 718 superalloy at room temperature was σ−1 = σb · (0.869−3.67 × 10−4 · σb). An analysis of the fatigue fracture mechanism showed that the fatigue fractures before and after aging were all initiated in the grains oriented relatively unfavorably on the surface of the sample, with a mixture of intergranular and transgranular propagation after the transgranular propagation of several grains. The higher plasticity of the solid solution state Inconel 718 alloy resulted in a large number of slip deformation zones under high cycle fatigue loads, and the plastic deformation was relatively uniform. The lengths of the secondary fractures were as high as 120 μm, which formed the single-source plastic fatigue fracture that promoted an increase in the fatigue limit. After aging treatment, the higher strength of the Inconel 718 alloy made dislocation slip difficult under high cycle fatigue loads, and the plasticity compatible deformation capability was poor. When local dislocations slipped to the intragranular γ” phase, γ’ phase, or interfaces with nonmetallic compounds (NMCs), plugging occurred. The degree of stress concentration increased, causing the initiation of fatigue fracture; the secondary fracture was approximately 20 μm. Brittle cleavage due to multiple sources significantly reduced the fatigue limit.

Features of the normal choriocapillaris with OCT-angiography: Density estimation and textural properties.

The main objective of our work is to perform an in depth analysis of the structural features of normal choriocapillaris imaged with OCT Angiography. Specifically, we provide an optimal radius for a circular Region of Interest (ROI) to obtain a stable estimate of the subfoveal choriocapillaris density and characterize its textural properties using Markov Random Fields. On each binarized image of the choriocapillaris OCT Angiography we performed simulated measurements of the subfoveal choriocapillaris densities with circular Regions of Interest (ROIs) of different radii and with small random displacements from the center of the Foveal Avascular Zone (FAZ). We then calculated the variability of the density measure with different ROI radii. We then characterized the textural features of choriocapillaris binary images by estimating the parameters of an Ising model. For each image we calculated the Optimal Radius (OR) as the minimum ROI radius required to obtain a standard deviation in the simulation below 0.01. The density measured with the individual OR was 0.52 ± 0.07 (mean ± STD). Similar density values (0.51 ± 0.07) were obtained using a fixed ROI radius of 450 μm. The Ising model yielded two parameter estimates (β = 0.34 ± 0.03; γ = 0.003 ± 0.012; mean ± STD), characterizing pixel clustering and white pixel density respectively. Using the estimated parameters to synthetize new random textures via simulation we obtained a good reproduction of the original choriocapillaris structural features and density. In conclusion, we developed an extensive characterization of the normal subfoveal choriocapillaris that might be used for flow analysis and applied to the investigation pathological alterations.

Carbonate–Hydrogenocarbonate Coexistence and Dynamics in Layered Double Hydroxides

Carbonated layered double hydroxides were fully characterized by vibrational spectroscopies, powder X-ray diffraction and solid-state NMR tuning the cations, the layer charge density, and the preparation method to get original structural and dynamical features within the materials. It clearly appears that carbonate and hydrogenocarbonate coexist in the same interlayer after contact with air and also that the hydrogenocarbonate quantity is correlated to the MII/MIII molar ratio constituting a strong pH probe of the interlayer space. Likewise, these two species are involved in an exchange process with atmospheric carbon dioxide, and hydrogenocarbonate proves to be the key parameter of exchange kinetics. These crucial results, extended to various cationic couples, could lead to new alternatives for carbon dioxide storage.

MoS2 nanosheets supported on reduced carboxylic multi-walled carbon nanotubes: An advanced catalyst for the hydrogen evolution reaction

One of the important breakthroughs in the realization of renewable hydrogen energy source is the development of innovative methods to produce non-noble-metal electrocatalysts for the hydrogen evolution reaction (HER). In this work, an efficient HER catalyst with a unique nanostructure that MoS2 nanosheets (NSs) supported on reduced carboxylic multi-walled carbon nanotubes (rCMWCNTs) has been synthesized by microwave-assisted. The preparation process is environmentally friendly, efficient, and suitable for mass production, including a liquid exfoliation technique of ultrasound probe sonication method to make small-sized MoS2 NSs and their subsequent microwave-assisted synthesis to be supported on rCMWCNTs. The study of the structural properties reveal that the MoS2 NSs supported on the rCMWCNTs are uniformly distributed and perfectly preserved their original superior structural features. The excellent catalytic performance of the as-prepared hybrid is verified by the electrochemical tests results, which exhibit a small Tafel slope of 66mV/decade and a low overpotential of −190mV. Moreover, according to the classic theory, the mechanism governing of the catalytic HER on the MoS2 NSs/rCMWCNTs nanohybrid has been clarified.

Free MoS2 Nanoflowers Grown on Graphene by Microwave-Assisted Synthesis as Highly Efficient Non-Noble-Metal Electrocatalysts for the Hydrogen Evolution Reaction.

Advanced approaches to preparing non-noble-metal electrocatalysts for the hydrogen evolution reaction (HER) are considered to be a significant breakthrough in promoting the exploration of renewable resources. In this work, a hybrid material of MoS2 nanoflowers (NFs) on reduced graphene oxide (rGO) was synthesized as a HER catalyst via an environmentally friendly, efficient approach that is also suitable for mass production. Small-sized MoS2 NFs with a diameter of ca. 190 nm and an abundance of exposed edges were prepared by a hydrothermal method and were subsequently supported on rGO by microwave-assisted synthesis. The results show that MoS2 NFs were distributed uniformly on the remarkably reduced GO and preserved the outstanding original structural features perfectly. Electrochemical tests show that the as-prepared hybrid material exhibited excellent HER activity, with a small Tafel slope of 80 mV/decade and a low overpotential of 170 mV.

Nanocomposite based on polyaniline emeraldine-base and α-Al2O3: A structural characterization

Abstract A ceramic-matrix nanocomposite based on polyaniline emeraldine base and aluminum oxide (PANI-EB/α-Al2O3) was obtained by in-situ polymerization. X-ray diffraction pattern presented peaks related to both materials. The level of crystallinity was estimated at about 53%. The average crystallite sizes of PANI-EB and α-Al2O3 were found to be ∼40 Å and 570 Å, respectively. Scanning electron microscopy showed polymerization over ceramic particles. Fourier-transform infrared spectroscopy suggested physical deposition. The electrical conductivity of the PANI-EB/α-Al2O3 nanocomposite was decreased by a factor of 80 when compared with that of pure PANI-EB. Therefore, the polymeric reinforcement and the ceramic matrix maintained their original structural features, but the electrical conductivity in the nanocomposite was reduced.

Homo- and heterodinuclear coordination polymers based on a tritopic cyclam bis-terpyridine unit: Structure and rheological properties

An innovative coordination polymer based on a tritopic ligand having the bis-terpyridine cyclam (CHTT) unit is explored. Homo- or heteronuclear 1D coordination polymers can be formed with bivalent metal ions such as Co(II) and Ni(II) in solvent DMF. Creep-recovery curves of the (CoII)2CHTT gels formed from 1D coordination polymers were analyzed with the Burgers model and demonstrated an original self-healing property, unusual in the class of molecular gels. The influence of the metal type was studied through the structural features using small-angle neutron scattering (SANS) experiments. In gels, the corresponding network involves genuine fibers (R ≈ 35 Å), bundles of these fibers and also a fraction of finite size aggregates (rods with aspect ratio f ≈ 3–5). We found that the distribution of these latter structural components is sensitive to the metal ions type. Such tritopic 1D coordination polymers exhibit a range of original structural features and a facile control of the developed structures in solutions and gels by tuning their thermodynamic parameters. The versatility associated to the intrinsic dynamic ability of the systems should pave the way to original properties for molecular devices.

Communication Between Information Systems Using Fuzzy Rough Sets

Communication between information systems is a basic problem in granular computing, and the concept of homomorphism is a useful mathematical tool to study this problem. In this paper, some properties of communication between information systems based on fuzzy rough sets are investigated. The concepts of fuzzy relation mappings between universes are first proposed in order to construct a fuzzy relation of one universe according to the given fuzzy relation on the other universe. The main properties of the mappings are studied. The notions of homomorphism of information systems based on fuzzy rough sets are then proposed, and it is proved that properties of relation operations in the original information system and structural features of the system, such as approximations of arbitrary fuzzy sets and attribute reductions, are guaranteed in its image system under the condition of homomorphism.

Microstructure and RRA treatment of LFEC 7075 aluminum alloy extruded bars

The microstructures after casting and extruding, the mechanical properties and electrical conductivity after RRA treatment of conventional DC casting and low frequency electromagnetic casting (LFEC) 7075 aluminum alloy were investigated. The results showed that finer grains which distributed more homogeneously was obtained in LFEC ingots compared with those conventional DC ingots. The extruded bars of LFEC alloy kept its fine grain features of original as-cast structure. In the RRA treatment, with the extension of second aging time, the tensile strength and hardness of alloy decreased, but the electrical conductivity increased. Meanwhile, as the second aging temperature raised, the phase change rate in precipitation also increased. Under the same conditions, extruded bars of LFEC alloy had better performance than that of conventional DC cast alloy. The optimum RRA heat treatment process was 120 °C/24 h+180 °C/30 min+120 °C/24 h. The LFEC extruded bars acquired tensile strength 676.64 MPa, hardness 198.18, and electrical conductivity 35.7% IACS respectively, which were higher than that in the T6 temper, indicating that a notable RRA response takes place in LFEC extruded bars, whose second-step retrogression time was 30 min, and it was suitable for mass production.

Antifungal activity of azole compounds CPA18 and CPA109 against azole-susceptible and -resistant strains of Candida albicans

In this study we investigated the in vitro fungistatic and fungicidal activities of CPA18 and CPA109, two azole compounds with original structural features, alone and in combination with fluconazole against fluconazole-susceptible and -resistant Candida albicans strains. Antifungal activities were measured by MIC evaluation and time-kill studies. Azole binding analysis was performed by UV-Vis spectroscopy. Hyphal growth inhibition and filipin and propidium iodide staining assays were used for morphological analysis. An analysis of membrane lipids was also performed to gauge alterations in membrane composition and integrity. Synergism was calculated using fractional inhibitory concentration indices (FICIs). Evaluation of cytotoxicity towards murine macrophages was performed to verify selective antifungal activity. Even though their binding affinity to C. albicans Erg11p is comparable to that of fluconazole, CPA compounds are active against resistant strains of C. albicans with a mutation in ERG11 sequences and/or overexpressing the ABC transporter genes CDR1 and CDR2, which encode ATP-dependent efflux pumps. Moreover, CPA18 is fungistatic, even against the two resistant strains, and was found to be synergistic with fluconazole. Differently from fluconazole and other related azoles, CPA compounds induced marked changes in membrane permeability and dramatic alterations in membrane lipid composition. Our outcomes suggest that CPA compounds are able to overcome major mechanisms of resistance in C. albicans. Also, they are promising candidates for combination treatment that could reduce the toxicity caused by high fluconazole doses, particularly in immunocompromised patients.