The study was carried out to investigate the changes in saturated (SFA), monoene (MUFA), trans (TFA), and polyunsaturated (PUFA) fatty acids and the key fatty acid ratios (SFA/UFA, cis PUFA/SFA, C18:2/C16:0 and C18:3/C16:0) during potato chips frying in canola oil using single bounce attenuated total reflectance FTIR (SB‐ATR‐FTIR) spectroscopy. The data obtained from GC‐FID were used as reference. The calibration of main fat groups and their key fatty acid ratios were developed by partial least square (PLS) regression coefficients using 4000 to 650 cm?1 spectral range. FTIR PLS regression for the predicted SFA, MUFA, TFA, and PUFA were found 0.999, 0.998, 0.998, and 0.999, respectively, whereas for SFA/UFA, cis PUFA/SFA, C18:2/C16:0 and C18:3/C16:0 the regression coefficients were 0.991, 0.997, 0.996, and 0.994, respectively. We conclude that FTIR‐PLS could be used for rapid and accurate assessment of changes in the main fat groups and their key fatty acid ratios ratio during the frying process. Practical applications: FTIR‐ATR method is very simple, rapid, and environmentally friendly. No sample preparation is required and one drop of oil is enough for FTIR analysis. The proposed method could be applied for quick determination of key fatty acid ratios in the food processing industry. 相似文献
The aim of this paper is to describe a novel and completely automated technique for carotid artery (CA) recognition, far (distal) wall segmentation, and intima-media thickness (IMT) measurement, which is a strong clinical tool for risk assessment for cardiovascular diseases. The architecture of completely automated multiresolution edge snapper (CAMES) consists of the following two stages: 1) automated CA recognition based on a combination of scale-space and statistical classification in a multiresolution framework and 2) automated segmentation of lumen-intima (LI) and media-adventitia (MA) interfaces for the far (distal) wall and IMT measurement. Our database of 365 B-mode longitudinal carotid images is taken from four different institutions covering different ethnic backgrounds. The ground-truth (GT) database was the average manual segmentation from three clinical experts. The mean distance ± standard deviation of CAMES with respect to GT profiles for LI and MA interfaces were 0.081 ± 0.099 and 0.082 ± 0.197 mm, respectively. The IMT measurement error between CAMES and GT was 0.078 ± 0.112 mm. CAMES was benchmarked against a previously developed automated technique based on an integrated approach using feature-based extraction and classifier (CALEX). Although CAMES underestimated the IMT value, it had shown a strong improvement in segmentation errors against CALEX for LI and MA interfaces by 8% and 42%, respectively. The overall IMT measurement bias for CAMES improved by 36% against CALEX. Finally, this paper demonstrated that the figure-of-merit of CAMES was 95.8% compared with 87.4% for CALEX. The combination of multiresolution CA recognition and far-wall segmentation led to an automated, low-complexity, real-time, and accurate technique for carotid IMT measurement. Validation on a multiethnic/multi-institutional data set demonstrated the robustness of the technique, which can constitute a clinically valid IMT measurement for assistance in atherosclerosis disease management. 相似文献
Chronic periodontitis poses long-term challenges in dentistry, requiring the development of innovative dental composites with biocompatibility, bone regeneration, and antibacterial properties. This study focuses on synthesis of novel injectable thermoresponsive hydrogels composed of chitosan, sodium bicarbonate, bioactive glass (20 and 40% w/w), and acetanilide drug (0.3 and 0.6% w/w). These hydrogels exhibit a sol–gel transition at 37°C, addressing periodontal challenges with reduced gelation time. The smooth flow characteristic was evaluated through 17-22 gauge syringe needles at low temperature. Rheological studies demonstrated pseudoplastic behavior, with viscosity decreasing as shear rate increases. Fourier transform infrared and x-ray diffraction analysis confirmed the bioactivity of hydrogels, forming a bone-like apatite layer in simulated body fluid. The drug-loaded hydrogels demonstrated promising in vitro antibacterial properties against dental pathogens, specifically Staphylococcus aureus and Pseudomonas aeruginosa. Drug dissolution analysis revealed relatively high release rate at 37°C, highlighting its role in rapidly eliminating bacterial colonies at the target site, while the subsequent sustained release contributes to the prevention of infection recurrence. Finally, biocompatibility was assessed with fibroblast, where the cells were observed anchoring into the polymeric chains of hydrogel through extended filopodia. 相似文献
Additional rolling fatigue experiments as well as pure sliding, bending, and scratching tests of the Si3N4 sand-blasted steel surface have been carried out. Acquired results reconfirm the extraordinary tenacity of the self-attaching Si3N4 surface layer in terms of both anti-fatigue and antiwear characteristics, especially in the “hybrid” ball bearing. It appears that this Si3N4 sand layer can be identified as a complex, self-organizing, and adaptive system. 相似文献
Perfluoropolyalkylether (PFPAE) fluids are of interest to the United States Air Force as potential high temperature liquid
lubricants in gas turbine engines. PFPAE fluids have desirable thermal and oxidative stability, and favorable temperature/viscosity
characteristics. However, their performance depends on the specific base fluids, additives, bearing material used as well
as contact conditions and environments. Screening tests using a modified ball‐on‐rod type rolling contact fatigue (RCF) tester
were conducted to study the effects of the above variables and lubricant circulation on fatigue life, wear and performance
of PFPAE. Post test lubricant samples were analyzed for changes in physical and chemical properties. Traditional testing for
viscosity, acid number and weight changes was performed. Fluid degradation was studied using Fourier transform infrared spectroscopy
(FTIR), gas chromatography with atomic emission detector (GC‐AED) and supercritical fluid chromatography (SFC). Elemental
analysis of the deposits formed at the tribocontact were determined by Auger electron spectroscopy (AES).
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
BACKGROUND & AIMS: Octreotide was shown to inhibit the growth of colon cancer and to reduce serum concentrations of tumor growth factors such as insulin-like growth factor I (IGF-I) and epidermal growth factor (EGF) in vitro and in animal models. Effects of octreotide on tumor cell kinetics and serum concentration of IGF-I and EGF in patients with colorectal cancer were evaluated. METHODS: Seventy-five patients with colorectal cancer were randomized to receive octreotide (200 micrograms daily) in the 2 weeks before surgery or the usual medications. Samples of tumor tissue were taken at endoscopy and at surgery. [3H]Thymidine labeling index and flow cytometry were used to assess the S-phase fraction. In octreotide-treated patients, plasma levels of IGF-I, EGF, and growth hormone were assessed before and after treatment. RESULTS: There was a statistically significant reduction in the mean percentage of the S-phase fraction as a result of octreotide treatment measured by both [3H]thymidine labeling index (P = 0.001) and flow cytometry (P = 0.001). No reduction in the percentage of the S-phase fraction was observed in the control group patients. Serum values of IGF-I were significantly reduced by octreotide, whereas EGF and growth hormone levels were not affected. CONCLUSIONS: Octreotide reduces the proliferative activity of tumor cells and the serum IGF-I levels in patients with colorectal cancer. This activity may have a role in the treatment of colorectal cancer. 相似文献
Engineering with Computers - In this research paper, smoothed particle hydrodynamics (SPH) with Johnson Holmquist damage model is adopted for modelling of the blast-induced fractures in Barre... 相似文献
In this paper, we have developed a new ElGamal-like public key cryptosystem based on the matrices over a groupring. The underlying hard problem for this cryptosystem is the conjugacy search problem. That is, we have replaced the exponentiation of elements by conjugacy. This makes the key generation step more efficient. We also talk about different security aspects against known attacks. The proposed scheme is found to be secure against known plaintext attack when encryption uses a different random key for every new plaintext.
Since powerful editing software is easily accessible, manipulation on images is expedient and easy without leaving any noticeable evidences. Hence, it turns out to be a challenging chore to authenticate the genuineness of images as it is impossible for human’s naked eye to distinguish between the tampered image and actual image. Among the most common methods extensively used to copy and paste regions within the same image in tampering image is the copy-move method. Discrete Cosine Transform (DCT) has the ability to detect tampered regions accurately. Nevertheless, in terms of precision (FP) and recall (FN), the block size of overlapping block influenced the performance. In this paper, the researchers implemented the copy-move image forgery detection using DCT coefficient. Firstly, by using the standard image conversion technique, RGB image is transformed into grayscale image. Consequently, grayscale image is segregated into overlying blocks of m × m pixels, m = 4.8. 2D DCT coefficients are calculated and reposition into a feature vector using zig-zag scanning in every block. Eventually, lexicographic sort is used to sort the feature vectors. Finally, the duplicated block is located by the Euclidean Distance. In order to gauge the performance of the copy-move detection techniques with various block sizes with respect to accuracy and storage, threshold D_similar = 0.1 and distance threshold (N)_d = 100 are used to implement the 10 input images in order. Consequently, 4 × 4 overlying block size had high false positive thus decreased the accuracy of forged detection in terms of accuracy. However, 8 × 8 overlying block accomplished more accurately for forged detection in terms of precision and recall as compared to 4 × 4 overlying block. In a nutshell, the result of the accuracy performance of different overlying block size are influenced by the diverse size of forged area, distance between two forged areas and threshold value used for the research.
In this work, solar cells based on methylammonium lead iodide (MAPbI3) doped in solution with C70 fullerene in a mesoporous as well as planar electron‐transporting layer (ETL)‐free architecture are realized, showcasing in the latter case a record efficiency of 15.7% and an improved open‐circuit voltage (VOC). Contrary to the bulk heterojunction previously reported, the C70 molecules do not phase segregate and they are rather finely dispersed in the perovskite film, possibly infiltrating at the grain boundaries, while assisting the growth of a highly uniform perovskite layer. By means of time‐resolved femtosecond‐to‐nanosecond optical spectroscopy, with an extended spectral coverage, it is observed that electrons photogenerated in the perovskite are transferred to C70 with a time constant of 20 ps. Despite being captured by C70, electrons are not deeply trapped and can potentially bounce back into the perovskite, as suggested by the high fill factor and enhanced VOC of the MAPbI3:C70 solar cells, especially in the case of the ETL‐free device configuration. 相似文献