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The outcomes of the research in modern cementitious composites have paved the way for their wide use in construction industry. The introduction of short, discontinuous and randomly distributed fibers to these composites has altered their inherent brittleness. Extensive research has been carried out on the effects of using of mono-fibers in a cementitious composite. However, limited reports in the approachable references on the use of hybrid fibers are available. The synergetic interaction between hybrid fibers have beneficial impact on cementitious composites. The incorporation of micro- and nano-pozzolanic materials, such as fly ash and silica fume have been used to develop high performance cementitious composites such as reactive powder concrete, DUCTAL and CEMTEC multiscale. Further developments were recently achieved by the development of ultra-high performance cementitious composites. The matter of developing high and ultrahigh cementitious composites using various kinds of fibers and particles has received enormous attention from the scientific community. This paper presents a comprehensive critical literature review on the area of high and ultra-high performance cement-based materials. [ABSTRACT FROM AUTHOR]

Background: In chronic kidney disease (CKD), inadequate nutritional intake, inflammation, and increased oxidative stress have been the major contributing factors in malnutrition pathogenesis. However, there is still a paucity of evidence assessing the magnitude of the effect of tooth loss on malnutrition in CKD populations. The authors hypothesize that among patients with CKD, tooth loss may affect nutritional status, using the National Health and Nutrition Examination Survey 1988 to 1994 (NHANES III). Methods: Glomerular filtration rate (GFR) was estimated based on cystatin C levels using the relevant equation. Grinary albumin-to-creatinine ratio (albuminuria) was calculated in milligrams per gram with a cutoff point of 30 mg/g. CKD was defined based on estimated GFR <60 mL/minute/ 1,73m² and albuminuria ≥30 mg/g. The cutoff point for serum albumin was set at 3.7 g/dL. Tooth loss categories were based on the number of missing and replaced teeth. Results: A total of 2,749 patients was included and stratified based on their oral health status. There was a statistically significant correlation between tooth loss and the proportion of patients with low protein and caloric intake (P = 0.02 and 0.01, respectively). Serum albumin reached a frequency peak in the fully edentulous group without dentures (group 4, 19.2%). In the same group, individuals had lower protein (30.1%) and caloric intake (30.2%) (P - 0.01 and 0.02, respectively). Furthermore, logistic regression analysis confirmed the significant role of tooth loss on serum albumin and protein and energy intake in this population even after adjusting for confounding variables. Conclusion: Tooth loss independently predicts low energy and protein intake, as well as serum albumin levels, biomarkers of malnutrition in CKD. [ABSTRACT FROM AUTHOR]

This prospective study investigated the important epidemiologic aspects of Clostridium difficile infections (CDIs) among Jordanian adult hospitalized patients. A total of 300 stool specimens were investigated using culture and polymerase chain reaction methods for detection of C difficile, its toxins, and fluoroquinolone resistance. C difficile-positive cultures were found in 13.7% of the patients, and 73% of the isolates carried tcdA and/or tcdB toxin genes, and all C difficile isolates were negative for binary toxin. The isolates showed moderate level of resistance to both ciprofloxacin and levofloxacin, whereas metronidazole and vancomycin were highly susceptible. This study indicates the need for early detection of CDIs and prevention of its severe disease in hospitalized patients. [Copyright &y& Elsevier]

Introduction The aim of our study was to investigate the dosimetric accuracy of Analytical Anisotropic Algorithm (AAA) and Acuros XB (AXB) with the two absorbed dose reporting options dose-to-medium ( D m) and dose-to-water ( D w). The calculations were carried out for small multi-leaf collimator (MLC) fields in heterogeneous media against Monte Carlo (MC) simulations and EBT3 radiochromic films measurements. The well-known approach of Siebers et al.1 used for converting D m to D w in MC codes was also investigated. Methods Two multilayered slab phantoms were used for this study. These phantoms consisted of soft tissue equivalent material with bone (1.82 g/cm3) or Lung (0.29 g/cm3) slabs. MC calculations were performed using GATE platform and were considered as benchmark for D m calculations. The AXB D m calculations were compared to those of GATE D m with the AXB library elemental compositions on one hand and with the experimental phantoms elemental compositions on the other hand. The results of the AAA, AXB D w and GATE D w . were compared against film measurements considered as D w reference. All calculations and measurements were performed for 6 MV photon beams delivered from a Truebeam linear accelerator with a 3 × 3 cm2 nominal MLC field. Results The AXB D m calculations showed excellent agreement with GATE D m when the calculations were performed with the same elemental compositions. However, an average difference of 2% and 1.6% was found between AXB D m and GATE D m with the experimental phantom compositions in Lung and bone, respectively. The GATE D w and AXB D w calculations were in agreement with films measurement with an average difference less than 1.5% for the Lung configuration. Conversely, an average differences of 3.1% was found with the AAA results after the lung region. The results of AXB and GATE calculations were significantly different compared to film measurements in the bone region. Differences were up to 10.4% and 7% for AXB D w and GATE D w , respectively. These results show that the conversion method used by AXB and GATE should be reviewed. Concerning the GATE conversion method, a fluence correction factor should be applied as mentioned by Andreo [1]. This factor was calculated for the studied media and good agreements were found with measurements after applying it. Conclusions The AXB was found to be more accurate than the AAA in the low density media. The current methods employed for converting D m to D w in AXB and GATE are invalid and should be corrected. Further studies on the calculation of electron spectra and fluence correction factors in different media and for various field sizes are ongoing. [ABSTRACT FROM AUTHOR]