912 resultados para CHARPY IMPACT PROPERTIES


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The link between off-target anticholinergic effects of medications and acute cognitive impairment in older adults requires urgent investigation. We aimed to determine whether a relevant in vitro model may aid the identification of anticholinergic responses to drugs and the prediction of anticholinergic risk during polypharmacy. In this preliminary study we employed a co-culture of human-derived neurons and astrocytes (NT2.N/A) derived from the NT2 cell line. NT2.N/A cells possess much of the functionality of mature neurons and astrocytes, key cholinergic phenotypic markers and muscarinic acetylcholine receptors (mAChRs). The cholinergic response of NT2 astrocytes to the mAChR agonist oxotremorine was examined using the fluorescent dye fluo-4 to quantitate increases in intracellular calcium [Ca2+]i. Inhibition of this response by drugs classified as severe (dicycloverine, amitriptyline), moderate (cyclobenzaprine) and possible (cimetidine) on the Anticholinergic Cognitive Burden (ACB) scale, was examined after exposure to individual and pairs of compounds. Individually, dicycloverine had the most significant effect regarding inhibition of the astrocytic cholinergic response to oxotremorine, followed by amitriptyline then cyclobenzaprine and cimetidine, in agreement with the ACB scale. In combination, dicycloverine with cyclobenzaprine had the most significant effect, followed by dicycloverine with amitriptyline. The order of potency of the drugs in combination frequently disagreed with predicted ACB scores derived from summation of the individual drug scores, suggesting current scales may underestimate the effect of polypharmacy. Overall, this NT2.N/A model may be appropriate for further investigation of adverse anticholinergic effects of multiple medications, in order to inform clinical choices of suitable drug use in the elderly.

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This paper investigates the effect of silica addition on the structural, textural and acidic properties of an evaporation induced self-assembled (EISA) mesoporous alumina. Two silica addition protocols were applied while maintaining the EISA synthesis route. The first route is based on the addition of a Na-free colloidal silica suspension (Ludox®), and the second method consists of the co-hydrolysis of tetraethyl orthosilicate (TEOS) with aluminium tri-sec-butoxide, to favour a more intimate mixing of the Al- and Si-hydrolysed species. The properties of the so derived materials were compared to the SiO2-free counterpart. The SiO2 addition was always beneficial from a structural and textural standpoint. TEOS appears to have a truly promoting effect; the ordering, surface area and pore volume are all improved. For Ludox®, the enhancement comes from the formation of smaller pores by a densification of the structure. The crystallization of γ-alumina depends on the interaction between the Al- and Si-species in the mesophase. Ludox®-based materials achieved crystallization at 750 °C but the intimate mixing in the TEOS-based mesophases shows a suppression of the phase transformation by 50-100 °C, with respect to the SiO2-free counterpart. This reduces the textural features substantially. For all SiO2-modified materials, the enhancement in the surface area is not accompanied by a concomitant improvement of total acidity, and the formation of weak Lewis acid sites was promoted. These effects were ascribed to SiO2 migration to the surface that blocks part of the acidity.

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OBJECTIVES: The aim of this study was to investigate the influence of process parameters during dry coating on particle and dosage form properties upon varying the surface adsorbed moisture of microcrystalline cellulose (MCC), a model filler/binder for orally disintegrating tablets (ODTs). METHODS: The moisture content of MCC was optimised using the spray water method and analysed using thermogravimetric analysis. Microproperty/macroproperty assessment was investigated using atomic force microscopy, nano-indentation, scanning electron microscopy, tablet hardness and disintegration testing. KEY FINDINGS: The results showed that MCC demonstrated its best flowability at a moisture content of 11.2% w/w when compared to control, comprising of 3.9% w/w moisture. The use of the composite powder coating process (without air) resulted in up to 80% increase in tablet hardness, when compared to the control. The study also demonstrated that surface adsorbed moisture can be displaced upon addition of excipients during dry processing circumventing the need for particle drying before tabletting. CONCLUSIONS: It was concluded that MCC with a moisture content of 11% w/w provides a good balance between powder flowability and favourable ODT characteristics.

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Le fromage Mozzarella entre dans la composition de plusieurs mets populaires d’Amérique du Nord. L’aptitude de ce fromage à être râpé et ses propriétés caractéristiques de cuisson en font un ingrédient idéal. Ces qualités sont attribuées principalement aux propriétés physiques particulières de ce fromage sous certaines conditions de cisaillement et de température. Le but de ce projet était d’évaluer l’impact de différentes stratégies couramment mises en oeuvre dans l’industrie fromagère sur la composition, la microstructure et les propriétés physiques du fromage. Diverses stratégies ont été étudiées : les conditions de filage du caillé lors du procédé de « pasta filata », l’addition de protéines sériques dénaturées, le contrôle de la minéralisation et le vieillissement du fromage. Les résultats ont démontré que le contrôle de l’intensité mécanique et thermique fournie lors du filage permettait respectivement de réduire les pertes de solides et d’améliorer la répartition de la phase aqueuse dans la matrice fromagère. L’aptitude au râpage du fromage peut être optimisée en combinant l’utilisation de plusieurs stratégies dont la réduction du calcium colloïdal, un temps de vieillissement adéquat et un râpage à basse température. Par ailleurs, des changements aux facteurs mentionnés précédemment sont apportés lors de l’ajout de protéines sériques dénaturées, ces dernières ayant un impact sur la composition et la structure du fromage. Des modèles prédictifs de l’aptitude au râpage ont été développés en sélectionnant uniquement les descripteurs de composition et de texture pertinents. La perception sensorielle du fromage cuit sur pizza et les propriétés physiques du fromage fondu ont été considérablement influencées par l’évolution physico-chimique du fromage au cours du vieillissement. L’utilisation d’une nouvelle approche pour la caractérisation des propriétés rhéologiques du fromage fondu sous fortes contraintes a permis d’établir de bonnes relations avec les descripteurs sensoriels de texture. Ce travail a permis de valider l’hypothèse que l’utilisation d’une ou plusieurs stratégies simples et accessibles pouvait être mise de l’avant afin d’optimiser les propriétés physiques du fromage Mozzarella. Cela contribue à une meilleure compréhension des facteurs pouvant être contrôlés afin de développer des fromages avec des attributs spécifiques, lorsqu’utilisés comme ingrédient.

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Soil erosion and unsustainable land use produce adverse effects on SOC content. Soil management techniques and corrections can be applied for soil recovery, especially, with afforestaion purposes. This study presents the short term effects on the application of different treatments on soil properties for soil included in several sets of closed plots located in the experimental area of Pinarillo (Nerja, Spain). The analysed soil properties were: PH, EC, organic carbon, total nitrogen and total carbon. In order to verify possible differences, we applied the test of Mann-Whitney U in corroboration with the previous homogeneity test of variance.

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The effects of different solvents on the recovery of (i) extractable solids (ES), (ii) total phenolic compounds (TPC), (iii) total flavonoid content (TFC), (iv) vitamin C, and (v) antioxidant activity from lemon pomace waste were investigated. The results revealed that solvents significantly affected the recovery of ES, TPC, TFC, and antioxidant properties. Absolute methanol and 50% acetone resulted in the highest extraction yields of TPC, whereas absolute methanol resulted in the highest extraction of TFC, and water had the highest recovery of vitamin C. 50% ethanol, and 50% acetone had higher extraction yields for TPC, and TFC, as well as higher antioxidant activity compared with their absolute solvents and water. TPC and TFC were shown to be the major components contributing to the antioxidant activity of lemon pomace.

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Irradiation has been increasingly recognized as an effective decontamination technique, also ensuring the chemical and organoleptic quality of medicinal and aromatic plants 1 . The use of medicinal plants in the prevention and or treatment of several diseases has revealed satisfactory results as anti-inflammatory, antimutagenic, anti-cancer and antioxidant agents 2 . The aim of the present study was to evaluate the effects of gamma irradiation on the cytotoxic properties and phenolic composition of Thymus vulgaris L. and Menta x piperita L. (methanolic extracts). Phenolic compounds were analyzed by HPLC-DAD-ESI MS, while the cytotoxicity of the samples was assessed in MCF-7 (breast adenocarcinoma), NCI-H460 (non-small cell lung cancer), HeLa (cervical carcinoma), HepG2 (hepatocellular carcinoma) cell lines, as also in non-tumor cells (PLP2). Thirteen and fourteen phenolic compounds were detected in T. vulgaris and M. piperita, respectively, but none of them was affected by the irradiation up to a dose of 10 kGy. However, despite there were no changes in the cytotoxic properties of irradiated peppermint samples in tumor cell lines, the thyme samples irradiated with 10 kGy showed higher cytotoxicity in comparison with the samples submitted to other doses (2 and 5 kGy). This highlights that 10 kGy can be a suitable dose to ensure the sanitary treatment, without modifying the bioactive composition and properties of these aromatic plants.

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Objective: Evaluate the validity, reliability, and factorial invariance of the complete Portuguese version of the Oral Health Impact Profile (OHIP) and its short version (OHIP-14). Methods: A total of 1,162 adults enrolled in the Faculty of Dentistry of Araraquara/UNESP participated in the study; 73.1% were women; and the mean age was 40.7 ± 16.3 yr. We conducted a confirmatory factor analysis, where χ2/df, comparative fit index, goodness of fit index, and root mean square error of approximation were used as indices of goodness of fit. The convergent validity was judged from the average variance extracted and the composite reliability, and the internal consistency was estimated by Cronbach standardized alpha. The stability of the models was evaluated by multigroup analysis in independent samples (test and validation) and between users and nonusers of dental prosthesis. Results: We found best-fitting models for the OHIP-14 and among dental prosthesis users. The convergent validity was below adequate values for the factors “functional limitation” and “physical pain” for the complete version and for the factors “functional limitation” and “psychological discomfort” for the OHIP-14. Values of composite reliability and internal consistency were below adequate in the OHIP-14 for the factors “functional limitation” and “psychological discomfort.” We detected strong invariance between test and validation samples of the full version and weak invariance for OHIP-14. The models for users and nonusers of dental prosthesis were not invariant for both versions. Conclusion: The reduced version of the OHIP was parsimonious, reliable, and valid to capture the construct “impact of oral health on quality of life,” which was more pronounced in prosthesis users.

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This study investigates fast pyrolysis bio-oils produced from alkali-metal-impregnated biomass (beech wood). The impregnation aim is to study the catalytic cracking of the pyrolysis vapors as a result of potassium or phosphorus. It is recognized that potassium and phosphorus in biomass can have a major impact on the thermal conversion processes. When biomass is pyrolyzed in the presence of alkali metal cations, catalytic cracking of the pyrolysis liquids occurs in the vapor phase, reducing the organic liquids produced and increasing yields of water, char, and gas, resulting in a bio-oil that has a lower calorific value and an increased chance of phase separation. Beech wood was impregnated with potassium or phosphorus (K impregnation and P impregnation, respectively) in the range of 0.10-2.00 wt %. Analytical pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) was used to examine the pyrolysis products during thermal degradation, and thermogravimetric analysis (TGA) was used to examine the distribution of char and volatiles. Both potassium and phosphorus are seen to catalyze the pyrolytic decomposition of biomass and modify the yields of products. 3-Furaldehyde and levoglucosenone become more dominant products upon P impregnation, pointing to rearrangement and dehydration routes during the pyrolysis process. Potassium has a significant influence on cellulose and hemicellulose decomposition, not just on the formation of levoglucosan but also other species, such as 2(5H)-furanone or hydroxymethyl-cyclopentene derivatives. Fast pyrolysis processing has also been undertaken using a laboratory-scale continuously fed bubbling fluidized-bed reactor with a nominal capacity of 1 kg h-1 at the reaction temperature of 525 °C. An increase in the viscosity of the bio-oil during the stability assessment tests was observed with an increasing percentage of impregnation for both additives. This is because bio-oil undergoes polymerization while placed in storage as a result of the inorganic content. The majority of inorganics are concentrated in the char, but small amounts are entrained in the pyrolysis vapors and, therefore, end up in the bio-oil.

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Residential property in New Zealand comprises both freestanding residential properties and medium to high density residential properties. Medium to high density residential property comprises the typical units, townhouses and semi-detached houses common in most residential property markets. However, in many of the larger cities of New Zealand the free standing residential property market has evolved into two separate markets being freehold residential property and cross lease residential property. Cross leases have developed as a form of infill housing to reduce the urban sprawl in major canters, while reducing the time and cost for residential property developers. A cross lease is created when an existing freestanding residential property subdivides a portion of the existing land for the erection of another house on the original title, basically dividing one larger residential section into two smaller residential blocks. This paper will analyse house prices in Christchurch over the period 1992 to 2006 to determine if the various housing markets have shown similar capital returns or if there is a specific preference for a particular residential property title.

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Severe flooding throughout England in Autumn 1998 and 2000, has seen an increase in the extent of flood liable residential areas throughout England, as well as an increase in the actual levels of flood damage in all previously recognised flood prone residential areas. The increasing cost of rectifying the damage caused to residential properties from flooding has been of some concern to the residential property valuation profession and sales and leasing agency practices. However, the increasing trend in the frequency of flooding in England, combined with an increase in severity of flooding is now causing some degree of concern in the residential insurance and housing finance sectors. In order to determine and quantify the impact of flooding and flood damage on the residential property market in England, a survey of Chartered Surveyors and Chartered Real Estate Valuers has been carried out across the main flood affected counties of England. This survey will provide similar details to the research completed by Eves (1999, 2001) and Fibbens (1993) in relation to residential property flooding in Australia. This survey provides comprehensive responses in relation to the degree of flood affectation across counties, the effect of flooding on residential property values, the impact of flooding on building insurance premiums and possible difficulties in obtaining finance to purchase residential property in recognised flood areas.

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The paper examines the decision by Australian Real Estate Trusts (A-REITs) to issue seasoned equity offerings from 2000 - 2008 and stock market reaction to the offerings. The findings reveal that highly leveraged A-REITs with variable earnings are less likely to issue seasoned equity offerings. Inconsistent results for structure and type of properties held by the A-REIT do not allow for inference to be drawn. Similar to previous studies of seasoned equity offerings, we find a significant negative abnormal return associated with their announcement and no evidence of excessive leakage of information. Furthermore, market reaction differences to announcements of SEOs for the pre-global financial crisis (GFC) (2000-2006) and GFC eras (2007-2008) are noted with GFC era shareholders incurring larger abnormal return losses at 1.13% in comparison to the pre-GFC era shareholder loss of 0.34% on the SEO announcement day. Cross-sectional regressions show that the issued amount, leverage and profitability are significant factors affecting abnormal returns. Growth opportunities, tangibility, operating risk, size of A-REIT and other variables capturing A-REIT structure and property types held do not have an impact on abnormal returns

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One of the more significant conveyancing decisions of 2005 was MNM Developments Pty Ltd v Gerrard [2005] QCA 230 (‘Gerrard’). Real estate agents, in particular, became concerned when the Court of Appeal raised grave doubts concerning the validity of a contract for the sale of residential property formed by the use of fax. As a result, the government acted quickly to introduce amendments to the Property Agents and Motor Dealers Act 2000 (Qld) (‘PAMDA’) and the Body Corporate and Community Management Act 1997 (Qld) (‘BCCMA’). The relevant Act is the Liquor and Other Acts Amendment Act 2005 (Qld). These amendments commenced on 1 December 2005. In the second reading speech, the Minister stated that these amendments would provide certainty for sellers of residential properties or their agents when transmitting pre-contractual documents by facsimile and other electronic means. The accuracy of this prediction must be assessed in light of the errors that may occur.

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Nightclubs are businesses. Their business is pleasure; however pleasure has its price. People have become increasingly concerned about the problems of violence in society but why do higher levels of violence occur in nightclubs despite the established patterns of behaviour that dictates how we socialise and act? In response, researchers have focused on identifying social and situational factors that may contribute to violence from a government perspective, focusing on a variety of specific issues ranging from financial standpoints with effective target marketing strategies to legal obligations of supplying alcohol and abiding regulatory conditions. There is little research into specific design properties that can determine design standards to ensure/improve the physical design of nightclub environments to reduce patron violence. To address this gap, this current article aims to understand how people experience and respond to the physical environment of nightclubs and how these spaces influence their behaviour. The first section of this paper examines the background on nightclubs and theories concerning the influence of pleasure. The second section of this paper details the findings of existing studies that have examined the nightlife context and the various factors that influence patron violence. The main finding of this paper is that although alcohol likely plays a contributing role in aggressive patron behaviour, there is evidence that the relationship is moderated by a number of significant factors relating to the characteristics of the drinking environment such as: physical comfort; the degree of overall 'permissiveness‘ in the establishment; crowding; and physical environmental elements most influenced by day to-day management practices such as lighting, ventilation, cleanliness and seating arrangements. The findings from this paper have been used to develop a framework to guide exploratory research on how specific elements of the physical environment of nightclubs have an impact on elevated patron aggression and assault (Koleczko & Garcia Hansen, 2011).