Numerical modelling of in-plane behaviour of adobe walls

Some tests for material characterization of adobe blocks and adobe masonry have been carried out in universities and laboratories around the world. However, the number of tests is quite limited in comparison with those carried out with other structural materials, such as masonry or reinforced concrete, and even those tests just refers to elastic properties. The results of adobe tests (i.e. compression strength, elasticity modulus, shear strength, etc.), as well as the results of cyclic and dynamic tests on adobe masonry components and small buildings show that the mechanical properties of adobe masonry and the seismic performance of adobe constructions highly depend on the type of soil used for the production of units and mortar. Basic properties, such as elasticity modulus, can have significant variation from one soil type to another. The state-of-the-art for the numerical modelling of unreinforced masonry point to three main approaches: macro-modelling, simplified micro-modelling and detailed micro-modelling. In all three approaches, the use of elastic and inelastic parameters is required. For adobe masonry, the lack of knowledge concerning some of the material properties makes numerical modelling more difficult. In the proposed work, the mechanical properties of the typical adobe masonry in Peru have been calibrated based on a cyclic in-plane test carried out on an adobe wall at the Catholic University of Peru (PUCP). The mechanical parameters calibration and the modelling results of the in-plane behaviour of the adobe wall are presented. Macro-modelling and simplified micro-modelling strategies are used in finite element software with an implicit solution strategy. The results of this work represent the first step for the numerical modelling of the seismic behaviour of adobe constructions

The use of continuum models for analyzing adobe structures

As it is known, the adobe structures have a high seismic vulnerability principally due to the low material strength and sometimes due to the inadequate structural configuration. One way for understanding the seismic behaviour of these structures is by experimental tests. However, those are costly and sometimes not easy to make. An alternative for this is the analysis of adobe structures by numerical tools with the possibility to make parametric studies for understanding the behaviour of different geometrical configurations. In a previous work, some adobe material parameters have been calibrated based on a cyclic in-plane test. In this paper, that work was extended to a numerical modelling of the non-linear dynamic behaviour of an adobe module experimentally tested at the Pontificia Universidad Católica del Perú. For this, a continuum model in the finite element program Abaqus/Explicit, was used to represent the adobe masonry as a homogeneous and isotropic material

Radiologic versus Endoscopic Placement of Percutaneous Gastrostomy in Amyotrophic Lateral Sclerosis: Multivariate Analysis of Tolerance, Efficacy, and Survival

PurposeTo compare percutaneous radiologic gastrostomy (PRG) and percutaneous endoscopic gastrostomy (PEG) in terms of tolerance, efficacy, and survival in patients with amyotrophic lateral sclerosis (ALS). Materials and Methods Forty patients with ALS (17 men; mean age, 66.1 years; range, 39–83 y) underwent 21 PEG and 22 PRG attempts (including three unsuccessful PEG attempts) from 1999 to 2005. To assess tolerance and efficacy, a successful and well tolerated placement was defined as any successful placement with no major or minor local complications or pain requiring opioid analgesic agents. Univariate analysis was performed for all recorded parameters, followed by multivariate analysis for successful and well tolerated placement, 6-month mortality rate, and survival. Results General success rates were 85.7% for PEG and 100% for PRG. Pain was more frequent in PRGs (81.8% vs 52.4%; P = .05). Successful and well tolerated placement was seen in 81.8% of PRGs and 57.1% of PEGs (P = 0.1). Advanced age (P = .02) and PRG (P = .07) were predictive of successful and well tolerated placement. The interval from diagnosis to placement (P = .001) and ability to perform spirometry (P = .002) were predictive of survival. Oximetry measurements (P = .007) and interval from diagnosis to placement (P = .02) were predictive of mortality at 6 months. Conclusions PRG is more efficacious and better tolerated than PEG, essentially because it avoids the respiratory decompensation that may occur in PEG. Therefore, PRG should be preferred in cases of ALS. Survival is linked to ALS evolution and not to the choice of PRG or PEG placement

Gastrostomie Percutanée Radiologique

Gastrostomy is mainly used to provide longterm enteral nutrition. Percutaneous techniques are generally preferred to surgery except for specific cases. Image-guided percutaneous gastrostomy, currently used less than the gastroscopy-guided technique, is a simple, reliable and advantageous technique in managing these frequently debilitated patients. The different aspects of the procedure will be described: indications, contraindications, technique, follow-up, main complications and technical variations

Experimental investigation on the bond behavior of a compatible TRM-based solution for rammed earth heritage

Despite the current awareness of the high seismic risk of earthen structures, little has been done so far to develop proper strengthening solutions for the rammed earth heritage. Based on the effectiveness of TRM for masonry buildings, the strengthening of rammed earth walls with externally bonded fibers using earth-based mortar is being proposed as a compatible solution. In this context, the investigation of bond behavior was conducted by means of direct tensile tests, pull-out tests and single lap-shear tests. The specimens were prepared using earth-based mortars and two different types of meshes (glass and nylon) while considering different-bonded lengths. The direct tensile tests on TRM coupons showed the high capacity of the nylon mesh in transferring stresses after cracking of the mortar. The pull-out tests highlighted that in the case of glass fiber mesh, the bond was granted by friction, while the mechanical anchorage promoted by the transversal yarns granted the bond of the nylon mesh. Finally, the single lap-shear tests showed that the adopted earth-based mortar seems to limit the performance of the strengthening.This work was supported by the Fundacao para a Ciencia e a Tecnologia [PTDC/ECM-EST/2777/2014, SFRH/BD/131006/2017, SFRH/BPD/97082/2013]

Reconceptualizing power and gendered subjectivities in domestic cooking spaces

Drawing on evidence from the Global North and South, this paper explores the power dynamics of domestic kitchens in different geographical contexts. Noting the gendered nature of domesticity, it contrasts those perspectives which regard women’s primary responsibility for foodwork as inherently oppressive, with others which see kitchens and associated domestic spaces as sites of potential empowerment for women. The paper explores the complex, spatially-distributed, character of power surrounding domestic foodwork, decentring Anglo-American understandings of the relationship between gender, power and domestic space by foregrounding the experiences of a range of women from across the globe. The paper also examines the increasing role of men in domestic settings, particularly in the Global North, assessing the extent to which their engagement in cooking and other domestic practices may be challenging conventional understandings of the relationship between gender, power and space. Focusing on the spatial dynamics of the domestic kitchen, this paper advances a more nuanced understanding of the co-constitutive nature of the relationship between gender and power, including the instabilities and slippages that occur in the performance of various domestic foodwork tasks. The paper advocates future research on the boundaries of home, work and leisure, focusing on their significance in the constitution and transformation of male and female subjectivities