Purpose
Computer-assisted techniques play an important role in craniomaxillofacial surgery. As segmentation of three-dimensional medical imaging represents a cornerstone for these procedures, the ...present study was aiming at investigating a deep learning approach for automated segmentation of head CT scans.
Methods
The deep learning approach of this study was based on the patchwork toolbox, using a multiscale stack of 3D convolutional neural networks. The images were split into nested patches using a fixed 3D matrix size with decreasing physical size in a pyramid format of four scale depths. Manual segmentation of 18 craniomaxillofacial structures was performed in 20 CT scans, of which 15 were used for the training of the deep learning network and five were used for validation of the results of automated segmentation. Segmentation accuracy was evaluated by Dice similarity coefficient (DSC), surface DSC, 95% Hausdorff distance (95HD) and average symmetric surface distance (ASSD).
Results
Mean for DSC was 0.81 ± 0.13 (range: 0.61 mental foramen – 0.98 mandible). Mean Surface DSC was 0.94 ± 0.06 (range: 0.87 mental foramen – 0.99 mandible), with values > 0.9 for all structures but the mental foramen. Mean 95HD was 1.93 ± 2.05 mm (range: 1.00 mandible – 4.12 mm maxillary sinus) and for ASSD, a mean of 0.42 ± 0.44 mm (range: 0.09 mandible – 1.19 mm mental foramen) was found, with values < 1 mm for all structures but the mental foramen.
Conclusion
In this study, high accuracy of automated segmentation of a variety of craniomaxillofacial structures could be demonstrated, suggesting this approach to be suitable for the incorporation into a computer-assisted craniomaxillofacial surgery workflow. The small amount of training data required and the flexibility of an open source-based network architecture enable a broad variety of clinical and research applications.
Most xanthan gum-based hydrogels are crosslinked by physical methods, but they typically have inadequate mechanical strength and low thermal, pH, and salt stability. To improve the physicochemical ...properties of XG-based hydrogels, this study applied periodate oxidation of XG to produce ring-opened products with dialdehyde groups for forming chemically crosslinked hydrogels. The research investigated the effects of oxidized xanthan gum (OXG) at different degrees on the properties of its hydrogels with N,O-carboxymethyl chitosan (NOCC), a water-soluble chitosan derivative. Results show that the rigidity and brittleness of NOCC/OXG hydrogels were enhanced with the increased oxidation of XG. Additionally, the swelling ratio of NOCC/OXG hydrogels was increased by 3.5 times and the degradation rate was reduced by 1.5 times. These hydrogels are promising biomaterials for drug delivery, cell therapy, or tissue regeneration applications.
In the quest of improving the photocatalytic efficiency of photocatalysts, the combination of two and more semiconductors recently has garnered significant attention among scientists in the field. ...The doping of conductive metals is also an effective pathway to improve photocatalytic performance by avoiding electron/hole pair recombination and enhancing photon energy absorption. This work presented a design and fabrication of porphyrin@g-C3N4/Ag nanocomposite using acid-base neutralization-induced self-assembly approach from monomeric porphyrin and g-C3N4/Ag material. g-C3N4/Ag material was synthesized by a green reductant of Cleistocalyx operculatus leaf extract. Electron scanning microscopy (SEM), X-ray diffraction (XRD), FT-IR spectroscopy, and UV–vis spectrometer were utilized to analyse the properties of the prepared materials. The prepared porphyrin@g-C3N4/Ag nanocomposite showed well integration of porphyrin nanostructures on the g-C3N4/Ag's surface, in which porphyrin nanofiber was of the diameter in nanoscales and the length of several micrometers, and Ag NPs had an average particle size of less than 20 nm. The photocatalytic behavior of the resultant nanocomposite was tested for the degradation of Rhodamine B dye, which exhibited a remarkable RhB photodegrading percentage. The possible mechanism for photocatalysis of the porphyrin@g-C3N4/Ag nanocomposite toward Rhodamine B dye was also proposed and discussed.
•Porphyrin-based nanomaterial prepared via self-assembly approach successfully.•A new porphyrin@g-C3N4/Ag nanocomposite with full characterizations was successfully prepared.•Porphyrin nanofiber/g-C3N4/Ag hybrid material formed to improve photon energy harvesting.•Porphyrin@g-C3N4/Ag nanocomposite showed 97% removal of pollutants.•Photocatalytic mechanism of g-C3N4@porphyrin for organic dye degradation was proposed.
Abstract This research aims to create innovative compounds that incorporate 1,2,4‐triazole and exhibit α‐glucosidase inhibitory potential. Similar to our previously reported series of N ‐aryl ...2‐{5‐(naphthalen‐1‐ylmethyl)‐4‐phenyl‐4 H ‐1,2,4‐triazol‐3‐ylthio}acetamide compounds, we explore here 4‐ethyl instead of 4‐phenyl as substituent. The synthesis process effectively yielded these compounds, with the highest yield reaching up to 91 % for compound N ‐phenyl‐2‐{5‐(naphthalen‐1‐ylmethyl)‐4‐ethyl‐4 H ‐1,2,4‐triazol‐3‐ylthio}acetamide 5 a . Their structures were validated through various spectroscopic techniques such as IR, 1 H‐NMR, 13 C‐NMR, and HR‐MS spectra, and for compounds 3 , 5 d , and 5 e by X‐ray diffraction. In vitro experiments revealed that only compound 5 g , marked by a 3‐hydroxy substitution on the N ‐phenylacetamide moiety, demonstrated higher α‐glucosidase inhibitory potential (IC 50 =158.4±3.4 μM) compared to the positive control, acarbose (IC 50 =351.3±1.8 μM). Molecular docking studies also coincide with in vitro assay by uncovering a strong hydrogen bond with residue Asp1526 along with other hydrophobic interactions of compound 5 g in the α‐glucosidase binding pocket. Compound 5 g showed a free binding energy of −9.7 kcal/mol, contrasting with acarbose (−8.0 kcal/mol). Despite the modest biological activity, this research underscores the simplicity and convenience of the procedure for synthesizing 1,2,4‐triazole‐based compounds, and contributes a key feature to the structure‐activity relationship of the triazole scaffold in the α‐glucosidase pocket.
Purpose
Artificial intelligence in computer vision has been increasingly adapted in clinical application since the implementation of neural networks, potentially providing incremental information ...beyond the mere detection of pathology. As its algorithmic approach propagates input variation, neural networks could be used to identify and evaluate relevant image features. In this study, we introduce a basic dataset structure and demonstrate a pertaining use case.
Methods
A multidimensional classification of ankle x-rays (
n
= 1493) rating a variety of features including fracture certainty was used to confirm its usability for separating input variations. We trained a customized neural network on the task of fracture detection using a state-of-the-art preprocessing and training protocol. By grouping the radiographs into subsets according to their image features, the influence of selected features on model performance was evaluated via selective training.
Results
The models trained on our dataset outperformed most comparable models of current literature with an ROC AUC of 0.943. Excluding ankle x-rays with signs of surgery improved fracture classification performance (AUC 0.955), while limiting the training set to only healthy ankles with and without fracture had no consistent effect.
Conclusion
Using multiclass datasets and comparing model performance, we were able to demonstrate signs of surgery as a confounding factor, which, following elimination, improved our model. Also eliminating pathologies other than fracture in contrast had no effect on model performance, suggesting a beneficial influence of feature variability for robust model training. Thus, multiclass datasets allow for evaluation of distinct image features, deepening our understanding of pathology imaging.
In the quest of improving the photocatalytic efficiency of photocatalysts, the combination of two and more semiconductors recently has garnered significant attention among scientists in the field. ...The doping of conductive metals is also an effective pathway to improve photocatalytic performance by avoiding electron/hole pair recombination and enhancing photon energy absorption. This work presented a design and fabrication of porphyrin@g-C
N
/Ag nanocomposite using acid-base neutralization-induced self-assembly approach from monomeric porphyrin and g-C
N
/Ag material. g-C
N
/Ag material was synthesized by a green reductant of Cleistocalyx operculatus leaf extract. Electron scanning microscopy (SEM), X-ray diffraction (XRD), FT-IR spectroscopy, and UV-vis spectrometer were utilized to analyse the properties of the prepared materials. The prepared porphyrin@g-C
N
/Ag nanocomposite showed well integration of porphyrin nanostructures on the g-C
N
/Ag's surface, in which porphyrin nanofiber was of the diameter in nanoscales and the length of several micrometers, and Ag NPs had an average particle size of less than 20 nm. The photocatalytic behavior of the resultant nanocomposite was tested for the degradation of Rhodamine B dye, which exhibited a remarkable RhB photodegrading percentage. The possible mechanism for photocatalysis of the porphyrin@g-C
N
/Ag nanocomposite toward Rhodamine B dye was also proposed and discussed.
Objective:To characterize viral co-infections among representative hospitalized measles cases during the 2014 Hanoi outbreak.Methods:Throat swabs were collected from 54 pediatric patients with ...confirmed measles,and molecular diagnostics performed for 10 additional viral respiratory pathogens(Influenza A/H1N1pdm09;A/H3N2 and influenza B;Parainfluenza 1,2,3;Respiratory Synctial Virus,RSV;human Metapneumovirus,hM PV;Adenovirus and Picornavirus).Results:Twenty-one cases(38.9%) showed evidence of infection with other respiratory viruses:15 samples contained measles plus one additional virus,and 6 samples contained measles plus 2 additional viruses.Adenovirus was detected as a predominant cause of co-infections(13 cases;24.1%),followed by RSV(6 cases;11.1%),A/H1N1pdm09(3 cases;5.6%),PIV3(3 cases;3.7%),Rhinovirus(3 cases;3.7%) and hM PV(1 case;1.96%).Conclusions:Viral co-infections identified from pediatric measles cases may have contributed to increased disease severity and high rate of fatal outcomes.Optimal treatment of measles cases may require control of multiple viral respiratory pathogens.
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