Changes In Texture Parameters Research Articles

Influence of the Surface Texture Parameters of Asphalt Pavement on Light Reflection Characteristics

The optical reflection characteristics of asphalt pavement have an important influence on road-lighting design, and the macrotexture and microtexture of asphalt pavement significantly affect its reflection characteristics. To investigate the impact of texture parameters on the retroreflection coefficient of asphalt pavement, the texture indices of rutted plate specimens and field asphalt pavement were obtained by a pavement texture tester, including the macrotexture surface area (S1), microtexture surface area (S2), macrotexture distribution density (D1), microtexture distribution density (D2), root mean square slope (Δq), skewness (Rsk), and steepness (Rku). The corresponding retroreflective coefficient RL was measured by using a retroreflectometer. In the laboratory experiments, rutted specimens of AC-13, SMA-13, and OGFC-13 asphalt mixtures were formed. The changes in texture parameters and the retroreflection coefficient of rutting specimens before and after rolling were studied, and a factor-influence model between macro- and microtexture parameters and RL was established, along with correlation models of the texture index and RL. The results show that after the rutting test, S1, S2, D1, D2, Δq, and Rku decreased, Rsk increased, and RL increased. In the single-factor model, the parameters could be used to characterize RL with high prediction accuracy, whereas for the onsite measurements, the parameters Δq, Rsk, and Rku could well characterize RL. The nonlinear model established, based on the BP neural network algorithm, improved the prediction accuracy. This research provides ideas for optimizing the reflection characteristics of asphalt pavement and a decision-making basis for road-lighting design.

Study on the changes of CT texture parameters before and after HCC treatment in the efficacy evaluation and survival predication of patients with HCC.

To investigate texture parameters of contrast-enhanced computed tomography (CT) images before and after transarterial chemoembolization (TACE) as a tool for assessing the therapeutic response and survival predication in hepatocellular carcinoma (HCC). Data of 77 HCC patients who underwent three-phase dynamic contrast-enhanced CT examination within 4 weeks before and 4-8 weeks after TACE were collected and efficacy evaluation was performed according to the modified Response Evaluation Criteria in Solid Tumors (mRECIST) standard. The remission group consisted of 31 patients (12 with complete remission+19 with partial remission), while the non-remission group consisted of 46 patients (27 with stable disease+19 with progressive disease). Full-volume manual delineation of the region of interest (ROI) and texture analysis of the ROI were performed on the CT images using FireVoxel software. Changes in the 48 texture parameters from three-phase CT images before and after TACE were calculated and compared between the two groups. The receiver operating characteristic (ROC) curve and the areas under the curve (AUC) were used to analyze the diagnostic performance of texture parameters. A multifactorial Cox model was used for predicting survival. The C-indices of texture parameter difference values with predictive value, texture features model, and texture features combined with mRECIST in predicting OS were compared with those of mRECIST. A total of 41 changes in texture parameters were statistically significant between the remission and non-remission groups. The receiver operating characteristic (ROC) curve showed that the AUC of changes in the 90th percentile in the arterial phase was the largest at 0.842. When the cut-off value was 70.50, the Youden index was the largest (0.621), and the sensitivity and specificity were 0.710 and 0.911, respectively. Three changes in texture parameters were independent factors associated with patient survival, with a hazard of 0.173, 2.068, and 1.940, respectively. The C-index of the OS predicted by the texture features model was not statistically different from that of the mRECIST (0.695 vs. 0.668, p=0.493). While the C-indices of skewness in the portal venous phase combined with mRECIST (0.729, p=0.015), skewness in the delayed phase combined with mRECIST (0.715, p=0.044), and skewness in both two phases combined with mRECIST (0.728, p=0.017) were statistically different. Changes in the texture parameters of CT images before and after TACE treatment can be used to obtain relevant grayscale histogram parameters for evaluating the early efficacy of TACE in HCC treatment. And the texture analysis combined with mRECIST may be superior to the mRECIST alone in predicting survival in HCC after TACE treatment.

Development and characterization of fish gelatin-based biodegradable film enriched with Lepidium sativum extract as active packaging for cheese preservation

The physical and functional properties of gelatin-based films enriched with organic extracts from Lepidium sativum seeds were studied. Gelatin was extracted from the skin of dogfish (Squalus acanthias) and the functional gelatin-based films were used to preserve cheese during chilled storage. Ethanol extract (LSE3) and gelatin-based film enriched with LSE3 at 20 μg/mL showed high antioxidant potential using various complementary methods. No significant difference was measured in the mechanical parameters of the enriched films in terms of thickness, tensile strength and elongation at break. LSE3 incorporation at the highest level slighltly decreased the film L∗ value from 90.30 ± 0.10 to 88.10 ± 0.12, while the b∗ value increased from 0.91 ± 0.07 to 8.89 ± 0.12. Wrapping the cheese with gelatin-based film enriched with 20 μg LSE3/mL reduced the syneresis by 40% and stabilized the color, peroxidation and bacteria growth as compared to the unwrapped sample after 6 days of storage. In addition, cheese wrapped with the active gelatin-based film showed the lowest changes in texture parameters. Overall results suggest the use of the enriched gelatin film as active packaging material to preserve cheese quality.

Variation in textural parameters of hepatic lesions during contrast medium injection.

Textural parameters extracted using quantitative imaging techniques have been shown to have prognostic value for hepatocellular carcinoma (HCC). To evaluate whether the contrast medium timing of the image acquisition affects the reproducibility of textural parameters in HCC and hepatic tissue. This retrospective study included 17 patients with 37 HCC lesions. Perfusion computed tomography (CT) was obtained after 50 mL contrast medium injection. HCC lesions were segmented for analysis. The gray-level co-occurrence (GLCM) textural analysis parameters, homogeneity, energy, entropy, inertia, and correlation were calculated. Variation was quantified by calculating the SD of each parameter during respective perfusion series and the inter lesion variation as the SD among the lesions. The average change in texture parameters in both HCC and hepatic tissue per second after injection was 0.01% to 0.3% of the respective texture parameter. In HCC, the average variation in homogeneity, energy, and entropy within each lesion after contrast medium injection was significantly less than the variation observed among the lesions (23% to 74%, P < 0.001). Significant differences in energy, entropy, inertia, and correlation between hepatic tissue and HCC were observed. However, when considering the intra-individual variation of hepatic tissue over time, only the HCC parameter energy was significantly outside that 95% confidence interval (P < 0.02). The contrast medium timing does not affect the reproducibility of textural parameters in HCC and hepatic tissue. Thus, contrast medium timing should not be an issue at CT texture analysis of HCC.

5-Fluorouracil induced liver toxicity in patients with colorectal cancer: role of computed tomography texture analysis as a potential biomarker.

To assess if CT texture analysis (TA) can serve as a biomarker of liver toxicity in patients with colorectal cancer treated with 5-fluorouracil (5-FU)-based chemotherapy. In this IRB-approved, HIPAA-compliant retrospective study, patients with colorectal cancer treated with 5-FU-based regimens during 2008-2010 were identified from institutional electronic database. Total 43 patients (23 women; mean age 56years) with normal baseline liver function tests (LFTs), availability of baseline (pre-chemotherapy) and first follow-up CT (median 1.7months, interquartile range (IQR) 1.5-2.5) performed during chemotherapy were included. Two single-slice ROI of right and left liver lobe were obtained on baseline and first follow-up CT for TA. Texture features [mean, entropy, kurtosis, skewness, mean of positive pixel, standard deviation (SD)] were extracted using a commercially available software (TexRAD; Feedback Medical Ltd, Cambridge, UK). Changes in texture parameters between baseline and follow-up CT were evaluated with Wilcoxon signed-rank test for patients with and without LFT elevation during chemotherapy. Patients with LFT elevation (n = 34; 79%) showed significantly different mean, entropy, skewness, and SD (p values range 0.007-0.047) between baseline and first follow-up CT. No significant changes in features were observed in patients without LFT elevation (n = 9; 21%). In 19 patients (56%), first follow-up CT was performed before elevation of LFTs was observed. This proof-of-concept study shows that there are early changes in liver texture on first follow-up CT in patients with LFT elevation during 5-FU-based chemotherapy for colorectal cancer. In more than 50% of cases, these changes occur before LFT elevation becomes evident on blood tests.

A non-invasive approach to assess texture changes in sous-vide cooked Atlantic mackerel during chilled storage by fluorescence imaging

The aim of this study was to investigate the potential of fluorescence microscopy coupled with chemical, physical and data analysis methods for reliable and non-invasive detection of changes in texture parameters of sous-vide cooked Atlantic mackerel during chilled storage. Fluorescence micrographs of cook loss and connective tissue of the fish samples after sous-vide treatment at 60 °C and 75 °C for 10, 15 and 20 min taken in the 1st, 3rd and 7th day of chilled storage were acquired. The obtained images were numerically processed and the resulting data was directly correlated (R = 0.960) with the total collagen content determined by a chemical method. Partial least squares analysis was applied to derive statistically significant regression models revealing the influence of each of sous-vide regime parameters on changes in total collagen content and texture parameters of Atlantic mackerel during chilled storage. Results showed that both collagen integrity and firmness of mackerel flesh were significantly (p < 0.05) affected by the temperature of sous-vide treatment and duration of chilled storage, leading to gradual softening of the fish tissue due to degradation of collagenous tissue.

The effects of sous-vide cooking parameters on texture and cell wall modifications in two apple cultivars: A response surface methodology approach.

This work aimed at evaluating the effects of sous-vide cooking parameters, such as time and temperature and their interactions, on textural attributes of 'Mondial Gala' and 'Granny Smith' apple cultivars. For this, different response surface methodology-based models were developed. This methodology proved a suitable means for the assessment of changes in textural parameters and cell wall modifications during the processing of apples. 'Mondial Gala' fruit displayed better aptitude for the preservation of textural properties after high-temperature processing conditions and were therefore apparently more suited to sous-vide cooking than 'Granny Smith' apples. Pectin methylesterase activity levels in 'Mondial Gala' apples were enhanced at mild temperatures and pectins in this cultivar displayed a lower degree of methylation. Therefore, the establishment of calcium-mediated linkages between cell wall polymers might have been favoured in 'Mondial Gala' apples, thus reinforcing tissues and improving the preservation of textural attributes, in comparison to 'Granny Smith' samples.

Emulsion characteristics, chemical and textural properties of meat systems produced with double emulsions as beef fat replacers

In recent years, double emulsions are stated to have a promising potential in low-fat food production, however, there are very few studies on their possible applications in meat matrices. We aimed to investigate the quality of beef emulsion systems in which beef fat was totally replaced by double emulsions (W1/O/W2) prepared with olive oil and sodium caseinate (SC) by two-step emulsification procedure. Incorporation of W1/O/W2 emulsion resulted in reduced lipid, increased protein content, and modified fatty acid composition. W1/O/W2 emulsion treatments had lower jelly and fat separation, higher water-holding capacity and higher emulsion stability than control samples with beef fat. Increased concentrations of W1/O/W2 emulsions resulted in significant changes in texture parameters. TBA values were lower in W1/O/W2 emulsion treatments than control treatment after 60days of storage. In conclusion, our study confirms that double emulsions had promising impacts on modifying fatty acid composition and developing both technologically and oxidatively stable beef emulsion systems.

Irregularities of crystallographic orientation and residual stresses in the crossed-lamellar shell as a natural functionally graded material.

The microstructures of different groups of molluscs are characterized by preferential orientations of crystallites (texture), leading to a significant anisotropy of the physical properties of the shells. A complementary characteristic, usually neglected, is the distribution of the residual stresses existing within the shell wall. By means of X-ray diffraction, we study the distribution of stresses with thickness in the shell wall of the gastropod Conus marmoreus, which has a microstructure of the crossed-lamellar type. The results revealed an extraordinary texture inhomogeneity and the existence of tensional residual stresses along the shell thickness, the origins of which are unknown. Some of the observed changes in textural parameters and stresses coincide with the transitions between shell layers, although other features are of unknown origin. Our results provide insight into the microstructural regularities that govern the mesoscale construction of shells, such as that of C. marmoreus.

SU‐E‐J‐265: Feasibility Study of Texture Analysis for Prognosis of Local Tumor Recurrence Within 5‐Years for Pharyngeal‐Laryngeal Carcinoma Patients Received Radiotherapy Treatment

Purpose:Pharyngeal and laryngeal carcinomas (PLC) are among the top leading cancers in Asian populations. Typically the tumor may recur and progress in a short period of time if radiotherapy fails to deliver a successful treatment. Here we used image texture features extracted from images of computed tomography (CT) planning and conducted a retrospective study to evaluate whether texture analysis is a feasible approach to predict local tumor recurrence for PLC patients received radiotherapy treatment.Methods:CT planning images of 100 patients with PLC treated by radiotherapy at our facility between 2001 and 2010 are collected. These patients were received two separate CT scans, before and mid‐course of the treatment delivery. Before the radiotherapy, a CT scanning was used for the first treatment planning. A total of 30 fractions were used in the treatment and patients were scanned with a second CT around the end of the fifteenth delivery for an adaptive treatment planning. Only patients who were treated with intensity modulated radiation therapy and RapidArc were selected. Treatment planning software of Eclipse was used. The changes of texture parameters between two CT acquisitions were computed to determine whether they were correlated to the local tumor recurrence. The following texture parameters were used in the preliminary assessment: mean, variance, standard deviation, skewness, kurtosis, energy, entropy, inverse difference moment, cluster shade, inertia, cluster prominence, gray‐level co‐occurrence matrix, and gray‐level run‐length matrix. The study was reviewed and approved by the committee of our institutional review board.Results:Our calculations suggested the following texture parameters were correlated with the local tumor recurrence: skewness, kurtosis, entropy, and inertia (p&lt;0.0.05).Conclusion:The preliminary results were positive. However some works remain crucial to be completed, including addition of texture parameters for different image features, sensitivity of tumor segmentation variations, and effect of image filtering.

&amp;lt;i&amp;gt;In Vivo&amp;lt;/i&amp;gt; 9.4T MRI and &amp;lt;sup&amp;gt;1&amp;lt;/sup&amp;gt;H MRS for Evaluation of Brain Structural and Metabolic Changes in the Ts65Dn Mouse Model for Down Syndrome

In the present study we investigated structural and metabolic modifications of the brain in the Ts65Dn mouse model of Down syndrome(DS)using both in vivo magnetic resonance imaging(MRI)and proton magnetic resonance spectroscopy(MRS). MRI was performed for further texture analysis and changes in texture parameters, including mean grey levels, contrast and homogeneity, and they were found in Ts65Dn compared to diploid littermates (2n). These phenotypic changes were different in the hippocampus and cerebellum, since in Ts65Dn mean grey levels increased in the cerebellum and decreased in the hippocampus. In addition, proton NMR spectra revealed differences in metabolite ratios. Levels of N-acetylaspartate(NAA)and glutamate(Glu), were lower compared to total creatine levels (CX), in the Ts65Dn brain. However, the most striking finding was an increase in the concentration of myo-inositol(Ins)and choline(Cho)in the hippocampus, whereas the Ins concentration was reduced in the cerebellum. Overall, these data illustrate that MRI and MRS are valuable assesment tools sufficiently sensitive to detect associated changes in different brain areas, thus providing new insight into the causative role of dosage-sensitive genes in the Ts65Dn DS mouse model.

The Dependence of Peleg's Coefficients on Selected Conditions of a Relaxation Test in Model Samples of Edam Cheese

AbstractThe first aim of this work was to compare the influence of using two probes (a 100‐mm plate and a 5‐mm spherical probe) during a compression test on the trends of hardness changes during ripening of Edam cheese. Both of the above‐mentioned probes were also applied in relaxation tests for a relaxation time of 30–300 s (10 arbitrary times were used). By means of Peleg's model, the values of a parameter (the extent of material relaxation) and b parameter (the initial rate at which the stress relaxes) were calculated. Moreover, the values of a and b parameters, obtained during 10 different relaxation times of the probe after reaching the maximum deformation of the sample (30–300 s), were compared (calculated on the basis of Peleg's model). Edam cheese during ripening (1–84 days) was used as a model product. The values of cheese hardness within the ripening period (determined by means of both of the above‐mentioned probes) strongly correlated among themselves and also with the sensorially evaluated rigidity. Only a parameter was able to provide an adequate description of the actual changes in cheese within the ripening period but only at a relaxation time of ≤120 s (after reaching the maximum deformation of the sample; valid for both probes tested). Longer relaxation times do not provide a relevant description of the changes in cheese texture during ripening. B parameter provided no relevant description of the changes in cheese during ripening in any of the relaxation times studied (concerning both probes).Practical ApplicationThe study compares the influence of the probes used (a 100‐mm plate and a 5‐mm spherical probe) on the ability to describe changes of selected texture parameters during the ripening period of Edam cheese by using simple compression and relaxation tests. Both types of probes proved to be successful in observing the actual changes in cheese texture during ripening by means of hardness parameter (determined by a simple compression test). Moreover, the information capability of both parameters of Peleg's model (a and b), applied to the data obtained from the relaxation tests with a relaxation time of 30–300 s (after reaching the maximum deformation), was studied. It was observed that only a parameter is suitable for assessing the changes within the ripening period of cheese, which holds true only for a relaxation time of ≤120 s (after reaching the maximum deformation; valid for both probes observed). Longer relaxation times do not provide a good correlation with sensorially evaluated changes in texture parameters. The users are given by instructions on how to perform relaxation tests and, above all, on how to choose the times after reaching the maximum deformation of a cheese sample.

Inactivation of Escherichia coli O157:H7 in dry-cured ham by high-pressure treatments combined with biopreservatives

The effect of high-pressure (HP) treatments combined with biopreservatives such as a commercial nisin or pediocin on the survival of Escherichia coli O157:H7 and the physicochemical, rheological and color characteristics of sliced dry-cured ham stored under mild temperature abuse conditions (8 °C) was investigated. Immediately after treatments, a synergistic antimicrobial effect was registered when 400 MPa and 500 MPa for 10 min combined with nisin were applied. After 60 d, this synergistic effect was only maintained with the combined treatment of 500 MPa and nisin. Counts of E. coli in dry-cured ham were not affected by either nisin or pediocin applied individually, whereas counts in pressurized samples were 3 log units lower than in non-treated dry-cured ham after 60 d of refrigerated storage. Changes in textural parameters caused by pressurization and biopreservatives were minor. Lightness (L*) values were slightly affected, with lower values in samples pressurized at 500 MPa in combination with bacteriocins and a trend to decrease during storage. Redness (a*) and yellowness (b*) were less modified by HP and biopreservatives and tended to diminish during refrigeration. The results obtained in the present work demonstrate the effectiveness of pressurization of sliced dry-cured ham at 500 MPa for 10 min combined with nisin on the inactivation of E. coli O157:H7.

Changes in the fruit texture parameters and composition of apricot cultivars during ripening

Apricot is an important fruit species in Hungary both for fresh consumption and processing. Physical parameters and change of nutrients of nine apricot cultivars were studied during the ripening period. Four Hungarian and five North-American apricot cultivars were chosen for investigation. Changes in the physical parameters were measured by three different methods (Magness-Taylor hand penetrometer, Bookfield CT3 Texture Analyser with TA 44 and TA 9 measuring head). Significant differences in flesh firmness among the cultivars were observed mainly at the beginning of ripening time. Adhesiveness, cohesiveness and chewiness of the fruits decreased continuously during ripening. The studied cultivars showed significant differences in these traits. Sugar and acid contents were also measured during ripening. The cultivars showed small differences in sugar content and bigger differences in acid content of the fruits. Our data measured and collected during this study can be useful in characterizing the apricot cultivars studied. Changes in the texture parameters responsible for transportability and the technological usability of the fruits were described across the whole ripening period. Our results may help growers as well as food technologists to determine the optimum harvest date of cultivars intended to be used for different purposes.

Effects of fibre type and kefir, wine lemon, and pineapple marinades on texture and sensory properties of wild boar and deer longissimus muscle

Fibre type percentage and changes in textural parameters, sensory properties as well as mean fibre cross sectional area (CSA), fibre shape, endomysium and perimysium thickness of wild boar and deer longissimus (L) muscle subjected to ageing with kefir, dry red wine, lemon and pineapple juice marinades for 4days were studied. Among the non-marinated and non-aged samples of muscles it was found that wild boar meat with its higher percentage of red fibres, higher CSA, thicker connective tissue as compared with deer meat, was harder, more springy and stringy.Muscles ageing, regardless of methods, resulted in a decrease in both the CSA and thickness of the connective tissue, and improve in fibre shape. As a consequence ageing caused a reduction in hardness, cohesiveness, springiness, and stringiness as well as in augmentation of tenderness, juiciness and general attractiveness of the muscles studied.As demonstrated by obtained data, regardless of ageing methods, deer L muscle contained more white fibres compared to wild boar muscle, were more susceptible to tenderization. The highest structural and textural changes, but the worst general attractiveness was found in muscles marinated with pineapple juice addition. Insignificantly lower changes in both quality traits were found in muscles aged with kefir marinade which at the same time were characterized by the high tenderness, the highest juiciness and general attractiveness.

Effect of vacuum packaging and pomegranate peel extract on quality aspects of ground goat meat and nuggets.

The effect of vacuum packaging and pomegranate peel extract on ground goat meat and cooked nuggets during refrigerated storage (4 ± 1°C) was evaluated. Three different treatments evaluated were: I). Aerobic packaging (AP); II) Vacuum packaging (VP) and III). Vacuum packaging along with 1% pomegranate peel extract (VP + PPE). Results of quality evaluation showed that VP and VP + PPE maintained a more stable colour than AP. In all treatments, a significant (P < 0.05) increase in hardness and gumminess of nuggets was observed during the storage. But, VP nuggets showed minimum changes in texture parameters. TBARS values were significantly (P < 0.05) lower in VP and VP + PPE than AP. In ground meat, VP reduced the TBARS by 27% and PPE reduced the TBARS by 41%. In nuggets, TBARS was decreased by 17% and 40% in VP and VP + PPE respectively. Total plate counts were significantly higher (>log 7) in AP than VP meat and nuggets. Thus VP and PPE have a synergistic antioxidant effect and VP extended the refrigerated shelf life of goat meat and nuggets.

CHANGES IN MUSCLE PROPERTIES DURING POSTMORTEM STORAGE OF FARMED SEA BREAM (SPARUS AURATA)

ABSTRACT This study assesses the effects of storage temperature on postmortem changes in textural parameters (firmness, water holding capacity), and their relationship with biochemical and electrophoretic determinations (muscle collagen content and solubility, amount and integrity of sarcoplasmic and myofibrillar proteins) in sea bream muscle. Storage at 1C resulted in a prolongation of the firmness compared with 4C, with no noticeable changes in water holding capacity. This delay in muscle softening at 1C could be partially explained by a limited proteolysis of some myofibrillar proteins, although inconsistent tendency was observed for other fractions. In contrast, the rate of muscle collagen degradation was higher at 4C compared with 1C, this becoming the main contributing factor to firmness losses. The great variety of protein fractions separated electrophoretically, and the relatively minor and contradictory changes observed suggest the unfeasibility of electrophoresis as a routine procedure for studying freshness in stored sea bream. PRACTICAL APPLICATIONSAccording to the results obtained, it is strongly recommended that the storage of sea bream (Sparus aurata) throughout the commercial chain is carried out at 1C, instead of the usual temperature of 4C. This modification clearly delays the process of muscle softening, thus improving objective quality in this species.The electrophoretic separation of muscle proteins has been previously proposed as a suitable procedure for assessing the freshness of fish during cold storage. However, the results obtained here indicate that the attempts aimed to the development of an electrophoretic procedure for detecting modifications in muscle proteins that could be correlated with flesh textural properties were unsuccessful. This is especially true if short‐term deterioration is assessed.

Image analysis of crumb digital images in Barbary bread enriched with soy flour

امروزه کنترل کیفیت نان، به ویژه در حجم وسیع تولید، ضرورت کاربرد روش های جدید را ایجاب می نماید. در این پژوهش تحلیل تصویر مغز نان بربری غنی شده با آرد سویا در دو زمان نگهداری انجام گرفت. میانگین اندازه حفرات و تخلخل با استفاده از نرم افزار ایمیج جی محاسبه شد. بعد برخالی تصاویر مغز نان با استفاده از نرم افزار متلب و تبدیل فوریه تصویر استخراج شد. ویژگی های بافت تصویرنان شامل کنتراست، انرژی، همبستگی و یکنواختی محاسبه شده، مورد تحلیل آماری قرار گرفت. زمان نگهداری بر بعد برخالی، تخلخل و پارامتر ها بافتی تاثیر معنی دار داشت. یافته های این پژوهش را می توان به عنوان روشی سریع، غیر مخرب، ارزان قیمت و عینی برای ارزیابی کیفیت مغز نان در نظر گرفت. واژه‌های کلیدی: آرد سویا، بعد برخالی، تحلیل تصویر، نان بربری

Preparation of Al–SBA-15 pellets with low amount of additives: Effect of binder content on texture and mechanical properties. Application to Friedel–Crafts alkylation

Colloidal silica sol was used as a binder for the preparation of Al–SBA-15 pellets. Only 18 wt.% of silica was sufficient to form pellets that possessed mechanical strength comparable with industrial catalysts. Moreover, these pellets exhibited only minor changes in texture parameters in comparison with parent powder (the decrease of mesopore surface area and mesopore volume was not higher than 25%). However, even such small amount of binder caused a substantial reduction of reaction rate in Friedel–Crafts alkylation of toluene with benzyl alcohol. The time to reach 50% conversion of benzyl alcohol was for the pellets containing 18 wt.% of silica about five times higher in comparison with binder-free pellets. This decrease in the reaction rate was due to a partial decay of acid sites by alkali ions present in the binder solution and increased diffusion hindrances inside catalyst pellets.

Texture analysis of MR images of patients with Mild Traumatic Brain Injury

BackgroundOur objective was to study the effect of trauma on texture features in cerebral tissue in mild traumatic brain injury (MTBI). Our hypothesis was that a mild trauma may cause microstructural changes, which are not necessarily perceptible by visual inspection but could be detected with texture analysis (TA).MethodsWe imaged 42 MTBI patients by using 1.5 T MRI within three weeks of onset of trauma. TA was performed on the area of mesencephalon, cerebral white matter at the levels of mesencephalon, corona radiata and centrum semiovale and in different segments of corpus callosum (CC) which have been found to be sensitive to damage. The same procedure was carried out on a control group of ten healthy volunteers. Patients' TA data was compared with the TA results of the control group comparing the amount of statistically significantly differing TA parameters between the left and right sides of the cerebral tissue and comparing the most discriminative parameters.ResultsThere were statistically significant differences especially in several co-occurrence and run-length matrix based parameters between left and right side in the area of mesencephalon, in cerebral white matter at the level of corona radiata and in the segments of CC in patients. Considerably less difference was observed in the healthy controls.ConclusionsTA revealed significant changes in texture parameters of cerebral tissue between hemispheres and CC segments in TBI patients. TA may serve as a novel additional tool for detecting the conventionally invisible changes in cerebral tissue in MTBI and help the clinicians to make an early diagnosis.