Construcción sismorresistente en tierra: la gran experiencia contemporánea de la Pontificia Universidad Católica del Perú

In many developing countries the most common alternative for dwelling construction is building with earth because the material is abundant and cheap. The quality of most traditional earthen construction is very low, because it is done informally, with little or no technical assistance. In seismic areas where earthen construction is common, every time an earthquake occurs, many dwellings collapse, causing considerable economic losses and tragic injuries and deaths. The professional and academic communities in some seismic countries have not remained indifferent to this important problem. Researchers at the Catholic University of Peru (PUCP) have been investigating on the construction of earthen buildings in seismic areas for about 40 years and have obtained invaluable results. This article describes the evolution of the knowledge generated at PUCP of reinforced earth, a material composed of earth and compatible reinforcements, with which it is possible to build seismic-resistant constructions.En muchos países en vías de desarrollo la alternativa de vivienda más común es la construcción con tierra, pues el material es abundante y barato. La construcción tradicional de viviendas de tierra se realiza informalmente, sin asesoría técnica. Por ello, la calidad de estas construcciones es generalmente muy baja. En zonas sísmicas donde se construye con tierra, cada vez que ocurre un terremoto colapsan muchas construcciones de este material, causando considerables pérdidas económicas y lamentables pérdidas de vidas. Las comunidades académicas y profesionales de algunos países sísmicos no han permanecido impasibles frente a esta grave situación. En el Perú, investigadores de la Pontificia Universidad Católica del Perú (PUCP) han venido investigando la construcción con tierra en áreas sísmicas desde hace cerca 40 años y han obtenido invalorables resultados. Este artículo describe la evolución del conocimiento generado en la PUCP del material tierra armada, compuesto por tierra y refuerzos compatibles, que permite lograr construcciones sismorresistentes

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]

Expression of AMPA and NMDA receptor subunits in the cervical spinal cord of wobbler mice

BACKGROUND: The localisation of AMPA and NMDA receptor subunits was studied in a model of degeneration of cervical spinal motoneurons, the wobbler mouse. Cervical regions from early or late symptomatic wobbler mice (4 or 12 weeks of age) were compared to lumbar tracts (unaffected) and to those of healthy mice. RESULTS: No differences were found in the distribution of AMPA and NMDA receptor subunits at both ages. Western blots analysis showed a trend of reduction in AMPA and NMDA receptor subunits, mainly GluR1 and NR2A, exclusively in the cervical region of late symptomatic mice in the triton-insoluble post-synaptic fraction but not whole homogenates. Colocalisation experiments evidenced the expression of GluR1 and NR2A receptors in activated astrocytes from the cervical spinal cord of wobbler mice, GluR2 did not colocalise with GFAP positive cells. No differences were found in the expression of AMPA and NMDA receptor subunits in the lumbar tract of wobbler mice, where neither motoneuron loss nor reactive gliosis occurs. CONCLUSION: In late symptomatic wobbler mice altered levels of GluR1 and NR2A receptor subunits may be a consequence of motoneuron loss rather than an early feature of motoneuron vulnerability

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