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Motion is unavoidable in dynamic [18F]-MK6240 positron emission tomography (PET) imaging, especially in Alzheimer’s disease (AD) research requiring long scan duration. To understand how motion correction affects quantitative analysis, we investigated two approaches: intra- and inter- frame motion correction (II-MC), which corrects for both the interframe and intraframe motion, and interframe only motion correction (IO-MC), which only corrects for the interframe motion. These methods were applied to 83 scans from 34 subjects, and we calculated distribution volume ratios (DVRs) using the multilinear reference tissue model with the two parameters (MRTM2) in tau-rich brain regions. Most of the studies yielded similar DVR results for both II-MC and IO-MC. However, in one scan of an AD subject, the inferior temporal region showed 14% higher DVR with II-MC compared to IO-MC. This difference was reasonable given the AD diagnosis, although similar results were not observed in other regions. Although discrepancies between IO-MC and II-MC results were rare, they underscore the importance of incorporating intraframe motion correction for more accurate and dependable PET quantitation, particularly in the context of dynamic imaging. These findings suggest that while the overall impact of intraframe motion correction may be subtle, it can improve the reliability of longitudinal PET data, ultimately enhancing our understanding of tau protein distribution in AD pathology.

Biopolymers obtained from renewable resources became the center of public interest by virtue of their environmental and commercial advantages. Natural polymers such as starch, almond gum, chitosan and arabic gum were investigated to get fully or partially biodegradable dielectric material. Thus, in this article we study the material properties of cashew gum. This biopolymer is an exudate collected from occidental anacardium tree. For this investigation, scanning electron microscopy of powder and thin film cashew gum showed homogenous and slightly rough surface morphology with visible wrinkles. The thermal analyses such as thermogravimetric (TGA) and differential scanning calorimeter were realized. thermogravimetric thermogram shows two distinct stages of decomposition. The first around 150°C is attributed to moisture evaporation with loss in weight of 9.7%. The second transition, between 255°C and 330°C, is related to the decomposition of cashew gum with loss in weight of 50%. UV-visible spectra of the cashew gum thin film show a low absorbance and high transmittance. For this material, we obtained a direct optical band gap around 4.56 eV. In addition, the dielectric and electrical characterizations lead to conclude that cashew gum may be interesting for transistor applications as a gate dielectric.

In this study, the surface chemistry and morphology, the photocatalytic and antibacterial potential of pure and chlorine doped indium sulfide thin films, produced by spray pyrolysis, were analyzed. The RMS roughness seems not to be significantly affected by the chlorine concentration in three of the doped films (around 12 nm). The roughness seems not to affect the characteristics of the films analyzed in this study. The samples presented a photocatalytic efficiency higher than 80%, but no correlation with the amount of Cl concentration was found. The antibacterial potential of the films was assessed against the multidrug-resistant bacteria Pseudomonas aeruginosa, responsible by serious infections, which are extremely difficult to treat in hospitals. The obtained results evidence an increase of antibacterial activity with the increase of Cl concentration. These results encourage further studies to support the potential of this material to be used in biomedical applications.

Cement or clinker phase quantification is considered as an important task for the control of the cement quality and its manufacturing conditions. Indeed, precise clinker phase quantification allows the prediction of cement properties and the identification of possible anomalies during its production process. However, the complexity of cement and clinker mineralogy makes this step very difficult. In this work, a study was carried out to quantify the mineralogical phases of four Portland cements and two clinkers using two different methods: The first is the traditional Bogue method and the second is X-ray diffraction coupled with Rietveld refinement. The comparison method results showed that the Rietveld method is the most precise and powerful tool for cement and clinker phase quantification since it takes into account the minor phases such as gypsum, anhydrite, and hemihydrate and differentiates between the polymorphism varieties of cement phases (M1alite, M3alite, β belite, and γ belite). However, it was shown that Bogue calculation remains a primary estimation method of only the major clinker phases (C3S, C2S, C3A, and C4AF). Only for calcite amount must be better estimated by thermogravimetric technique or calcimetry method than Rietveld method, since there is an overlapping of the peaks of calcite and alite.

Accurate, rapid methods for controlling and determining composition are necessary to aid in classification of cements and for correlation of performance characteristics with composition. X-ray fluorescence (XRF) is used to adjust the raw material proportions and to control the process conditions. The aim of the present study was to establish a reliable analytical program by X-ray fluorescence spectrometry, based on the choice of a well-defined range of standards, which are used to control the quality of the clinker. The results showed a second order polynomial regression model that could properly interpret the experimental data with an R2value >0.97 even after correction for some elements. The results obtained indicate the reliability, reproducibility, and the ease of use of the established program.

The work describes an application of a recently developed machine-learning technique called Mondrian predictors to risk assessment of ovarian and breast cancers. The analysis is based on mass spectrometry profiling of human serum samples that were collected in the United Kingdom Collaborative Trial of Ovarian Cancer Screening. The work describes the technique and presents the results of classification (diagnosis) and the corresponding measures of confidence of the diagnostics. The main advantage of this approach is a proven validity of prediction. The work also describes an approach to improve early diagnosis of ovarian and breast cancers since the data in the United Kingdom Collaborative Trial of Ovarian Cancer Screening were collected over a period of 7 years and do allow to make observations of changes in human serum over that period of time. Significance of improvement is confirmed statistically (for up to 11 months for ovarian cancer and 9 months for breast cancer). In addition, the methodology allowed us to pinpoint the same mass spectrometry peaks as previously detected as carrying statistically significant information for discrimination between healthy and diseased patients. The results are discussed.The work describes an application of a recently developed machine-learning technique called Mondrian predictors to risk assessment of ovarian and breast cancers. The analysis is based on mass spectrometry profiling of human serum samples that were collected in the United Kingdom Collaborative Trial of Ovarian Cancer Screening. The work describes the technique and presents the results of classification (diagnosis) and the corresponding measures of confidence of the diagnostics. The main advantage of this approach is a proven validity of prediction. The work also describes an approach to improve early diagnosis of ovarian and breast cancers since the data in the United Kingdom Collaborative Trial of Ovarian Cancer Screening were collected over a period of 7 years and do allow to make observations of changes in human serum over that period of time. Significance of improvement is confirmed statistically (for up to 11 months for ovarian cancer and 9 months for breast cancer). In addition, the methodology allowed us to pinpoint the same mass spectrometry peaks as previously detected as carrying statistically significant information for discrimination between healthy and diseased patients. The results are discussed.

On Febr. 26, this publication reported on an upcoming event in Garden City that could be the first step toward legislative action on sick Building Syndrome (SBS) and its impact [...]

This study was done to better understand how lipases are activated at an interface. We investigated the conformational and solvation changes occurring during the adsorption of Humicola lanuginosa lipase (HLL) onto a hydrophobic surface using Fourier transform infrared-attenuated total reflection spectroscopy. The hydrophobic surfaces were obtained by coating silicon attenuated total reflection crystal with octadecyltrichlorosilane. Analysis of vibrational spectra was used to compare the conformation of HLL adsorbed at the aqueous-solid interface with its conformation in solution. X-ray crystallography has shown that HLL exists in two conformations, the closed and open forms. The conformational changes in HLL caused by adsorption onto the surface were compared with those occurring in three reference proteins, bovine serum albumin, lysozyme, and α-chymotrypsin. Adsorbed protein layers were prepared using proteins solutions of 0.005 to 0.5mg/mL. The adsorptions of bovine serum albumin, lysozyme, and α-chymotrypsin to the hydrophobic support were accompanied by large unfoldings of ordered structures. In contrast, HLL underwent no secondary structure changes at first stage of adsorption, but there was a slight folding of β-structures as the lipase monolayer became complete. Solvation studies using deuterated buffer showed an unusual hydrogen/deuterium exchange of the peptide CONH groups of the adsorbed HLL molecules. This exchange is consistent with the lipase being in the native open conformation at the water/hydrophobic interface.

We investigated the surface behavior of gum Arabic (GA) as well as its effects on the lipolytic activity of human pancreatic lipase (HPL) and Humicola lanuginosa lipase (HLL), using emulsions of triacylglycerols (TAG) with various chain lengths. The effects of GA on the interfacial binding of HPL were also investigated. In the presence of 4 mM sodium taurodeoxycholate (NaTDC), GA (3% w/v, final concentration) had no effect on the HPL activity measured in the presence of colipase, whatever the type of TAG used. However, in the absence of bile salts or at low bile salt concentrations, GA inhibited the HPL activity when trioctanoin (TC8) and purified soybean oil (PSO) were used as substrates. At 3% (w/v, final concentration), GA strongly desorbed pure HPL from the TC8 interface and the classical anchoring effect of colipase was clearly observed. Both crude and dialyzed GA solutions were found to be highly tensioactive at the air–water as well as the oil–water interface using the drop technique. In conclusion, GA, or a putative contaminant present in GA, was found to be surface active and to have similar effects to those of bile salts on the interfacial binding and activity of HPL. Copyright 2001 Academic Press.

ObjectiveTo evaluate the effectiveness and safety of percutaneous balloon mitral commissurotomy for the treatment of pregnant women with severe mitral stenosis over a period of six years.DesignAnalysis of clinical, haemodynamic, and echocardiographic data before and immediately after the procedure, the pregnancy outcome, and the fate of newborn babies.SettingAcademic cardiovascular centre in Monastir, Tunisia.Patients44 pregnant patients who underwent percutaneous transvenous dilatation of the mitral valve between January 1990 and February 1996. Grade 2 mitral regurgitation was present in two patients and densely calcific valves in three (7%).ResultsCommissurotomy was successfully achieved in all cases. The total mean (SD) duration of the procedure was 72 (18) minutes and that of fluoroscopy 16 (7) minutes. Left atrial pressure decreased from 28 (10) to 14 (7) mm Hg, mitral pressure gradient fell from 22 (8) to 5 (3) mm Hg. Cardiac output increased from 4·8 (1·1) to 6·3 (1·2) l/min and Gorlin mitral valve area from 0·96 (0·21) to 2·4 (0·4) cm² (all P << 0·001). Cross sectional echocardiographic mitral valve area increased from 1·07 (0·21) to 2·32 (0·36) cm². There were no maternal or fetal deaths. Complications included a grade 4 mitral regurgitation in one patient that required early valve replacement. All patients delivered at full term, 42 vaginally and two (5%) by caesarean section; 41 babies were normal and three whose mothers had the procedure near term were relatively hypotrophic. At a mean follow up of 28 (12) months (range 2 to 26) all children had normal growth.ConclusionsDuring pregnancy, balloon mitral commissurotomy is the treatment of choice of severe pliable mitral stenosis in patients who are refractory to medical treatment.

A forgery image detection system is introduced to detect the forgery in images using global, local and pixel based features. Global features will consider the whole images which include luminance and chrominance features. These global features can be extracted by using Zernike moments. The local feature consists of descriptors of multiple interest points. Image authentication is done by using hash method. The set of images will be trained in the database earlier itself. Then the test image and reference image will be compared based on pixels. By analyzing the hash distance the system can identify the test image is forged or not. As an improvement, pixel based feature extraction is used. Pixel based feature extraction is carried out by using supervised classification algorithm.