Different fiber materials as reinforcement for geopolymer composite

For the last two centuries, Ordinary Portland Cement (OPC) is the most popular building material in the world due to its high mechanical properties, ease of handling and low cost. However, the concrete industry is known to leave an enormous environmental footprint. Therefore, the development of sustainable materials that could replace the OPC is essential. One of such recent developments is an aluminosilicate based material that can be activated in an alkaline medium to form a hardened sustainable product, known as ‘Geopolymer’. Geopolymers exhibit equal or better engineering properties as compared to conventional concrete with better environmental foot print. However, geopolymer\u27s main disadvantage, as concrete, is its brittleness and low tensile properties. One way to overcome this limitation is by addition of fibers, as they can control cracking by crack bridging, resulting in an increase of the tensile properties of the geopolymeric composite. The purpose of this research was to develop a high performance geopolymer composite by addition of short fibers. Three different types of fibers were added to the matrix with two different fiber contents (0.5% and 1%). The idea was to add fibers of significant difference in their chemical nature and tensile properties: PP and Carbon fibers which are both hydrophobic, but have significant differently tensile behavior, and PVA which is hydrophilic like the geopolymeric matrix, and has moderate tensile properties. Their influence on the geopolymer flexural behavior was examined. The microstructure of the composite at the fracture surface was also studied to better understand the role of the fibers. The results of this research showed that all fibers improved the ductility and toughness of the matrix. Geopolymeric composites with 1% carbon fibers showed the highest flexural strength, +216% compared to plain matrix, followed by the PVA fiber composites. Different failure modes were observed – fiber pull-out for the PP and carbon composites, and fiber rupture for the PVA fiber composite. This can be explained based on the different chemical nature of the fibers which produce a different matrix-fiber interface

Pudendusneuralgie: Anatomisch-chirurgische Aspekte

Zusammenfassung: Anatomie:: Das Perineum wird hauptsächlich von den Nervi pudendi versorgt. Der Nervus pudendus, ein tiefliegender Dammnerv, durchläuft mehrere Zonen, in denen Kompressionen auftreten können: zwischen dem Ligamentum supraspinatum und dem Ligamentum sacrococcygeum, zwischen dem Ligamentum sacrotuberale und dem Ligamentum sacrospinale, im Alcock-Kanal sowie im Bereich des Musculus obturatorius internus. Eine derartige Kompression kann zu einem Schmerzsyndrom im Dammbereich führen. Symptome:: Klinisch äußert sich die Kompression des Nervus pudendus durch neurologische Symptome einer Nervenkompression. Derartige Kompressionen können zu schwer diagnostizierbaren Schmerzzuständen führen. Brennende Schmerzen im Dammbereich, die eindeutig dem Versorgungsgebiet des Nervus pudendus zugeordnet werden können, im Sitzen verstärkt und einseitig auftreten, müssen an eine Kompression des Nervus pudendus denken lassen. Diagnose:: Die Diagnose stützt sich auf Anamnese und Klinik. Elektrophysiologische und bildgebende Untersuchungen dienen dem Ausschluss anderer Pathologien. Die diagnostische Infiltration des Canalis pudendalis kann in 30-40% der Fälle therapeutisch sein. Ein chirurgischer Eingriff zur Dekompression ist in 65-70% der Fälle erfolgreich. Da die Besserung oft nicht sofort eintritt, müssen die Patienten über diese Tatsache präoperativ informiert werden. Eine multidisziplinäre Betreuung ist unerlässlic

LIS1 and platelet-activating factor acetylhydrolase (Ib) catalytic subunits, expression in the mouse oocyte and zygote

AbstractPlatelet-activating factor is a phospholipid with several documented roles in the pre-implantation embryo. Enzymes that belong to the platelet-activating factor acetylhydrolases family inactivate platelet-activating factor. Cytosolic platelet-activating factor acetylhydrolase (Ib) is a heterotetramer composed of two catalytic subunits (α1/α2) and two regulatory LIS1 subunits. The expression of these components was monitored in the mouse oocytes and zygotes using reverse-transcribed PCR and Western blot analysis. Interestingly, these proteins are expressed in the oocyte and zygote and their expression increases after fertilization, probably due to stabilization of maternal RNA. Lis1 mRNA transcription also increases after fertilization. However, assaying for expression of a specific paternal LIS1 isoform detected no zygotic translation in the one cell stage. These findings suggest a potential role for platelet-activating factor acetylhydrolase (Ib) components in the early mouse embryo

Demographic Effects on Longitudinal Semantic Processing, Working Memory, and Cognitive Speed

OBJECTIVES To better understand and compare effects of aging and education across domains of language and cognition, we investigated whether 1) these domains show different associations with age and education, 2) these domains show similar patterns of age-related change over time, and 3) education moderates the rate of decline in these domains. METHODS We analyzed data from 306 older adults aged 55-85 at baseline of whom 116 returned for follow-up 4-8 years later. An exploratory factor analysis identified domains of language and cognition across a range of tasks. A confirmatory factor analysis analyzed cross-sectional associations of age and education with these domains. Subsequently, mixed linear models analyzed longitudinal change as a function of age and moderation by education. RESULTS Two language domains, i.e., semantic control and semantic memory efficiency, and two cognitive domains, i.e., working memory and cognitive speed, were identified. Older age negatively affected all domains, but semantic memory efficiency and higher education positively affected all domains except cognitive speed at baseline. In language domains, a steeper age-related decline was observed after age 73-74 compared to younger ages, while cognition declined linearly with age. Greater educational attainment did not protect the rate of decline over time in any domain. DISCUSSION Separate domains show varying effects of age and education at baseline, language versus cognitive domains show dissimilar patterns of age-related change over time, and education does not moderate the rate of decline in these domains. These findings broaden our understanding of age effects on cognitive and language abilities by placing observed age differences in context.Objectives: To better understand and compare effects of aging and education across domains of language and cognition, we investigated whether (a) these domains show different associations with age and education, (b) these do- mains show similar patterns of age-related change over time, and (c) education moderates the rate of decline in these domains. Method: We analyzed data from 306 older adults aged 55–85 at baseline of whom 116 returned for follow-up 4–8 years later. An exploratory factor analysis identified domains of language and cognition across a range of tasks. A confirmatory factor analysis analyzed cross-sectional associations of age and education with these domains. Subsequently, mixed linear models analyzed longitudinal change as a function of age and moderation by education. Results: We identified 2 language domains, that is, semantic control and semantic memory efficiency, and 2 cognitive domains, that is, working memory and cognitive speed. Older age negatively affected all domains except semantic memory efficiency, and higher education positively affected all domains except cognitive speed at baseline. In language domains, a steeper age-related decline was observed after age 73–74 compared to younger ages, while cognition declined linearly with age. Greater educational attainment did not protect the rate of decline over time in any domain. Discussion: Separate domains show varying effects of age and education at baseline, language versus cognitive domains show dissimilar patterns of age-related change over time, and education does not moderate the rate of decline in these domains. These findings broaden our understanding of age effects on cognitive and language abilities by placing observed age differences in context.Peer reviewe

Everolimus plus exemestane in postmenopausal patients with HR(+) breast cancer: BOLERO-2 final progression-free survival analysis.

IntroductionEffective treatments for hormone-receptor-positive (HR(+)) breast cancer (BC) following relapse/progression on nonsteroidal aromatase inhibitor (NSAI) therapy are needed. Initial Breast Cancer Trials of OraL EveROlimus-2 (BOLERO-2) trial data demonstrated that everolimus and exemestane significantly prolonged progression-free survival (PFS) versus placebo plus exemestane alone in this patient population.MethodsBOLERO-2 is a phase 3, double-blind, randomized, international trial comparing everolimus (10 mg/day) plus exemestane (25 mg/day) versus placebo plus exemestane in postmenopausal women with HR(+) advanced BC with recurrence/progression during or after NSAIs. The primary endpoint was PFS by local investigator review, and was confirmed by independent central radiology review. Overall survival, response rate, and clinical benefit rate were secondary endpoints.ResultsFinal study results with median 18-month follow-up show that median PFS remained significantly longer with everolimus plus exemestane versus placebo plus exemestane [investigator review: 7.8 versus 3.2 months, respectively; hazard ratio = 0.45 (95% confidence interval 0.38-0.54); log-rank P < 0.0001; central review: 11.0 versus 4.1 months, respectively; hazard ratio = 0.38 (95% confidence interval 0.31-0.48); log-rank P < 0.0001] in the overall population and in all prospectively defined subgroups, including patients with visceral metastases, [corrected] and irrespective of age. The incidence and severity of adverse events were consistent with those reported at the interim analysis and in other everolimus trials.ConclusionThe addition of everolimus to exemestane markedly prolonged PFS in patients with HR(+) advanced BC with disease recurrence/progression following prior NSAIs. These results further support the use of everolimus plus exemestane in this patient population. ClinicalTrials.gov #NCT00863655