Centrifuge modelling of building response to tunnel excavation

Understanding the building response to tunnelling-induced settlements is an important aspect of urban tunnelling in soft ground. Previous centrifuge modelling research demonstrated significant potential to study this tunnel–soil–structure interaction problem. However, these recent studies were limited by simplified building models, which might result in uncertainties when interpreting the building performance to tunnelling subsidence. This paper presents an experimental modelling procedure and the results of a series of centrifuge tests, involving relatively complex surface structures subjected to tunnelling in sand. Powder-based three-dimensional (3D) printing was adopted to fabricate building models with realistic layouts, facade openings and foundations. The 3D printed material had a Young's modulus and a brittle response similar to historic masonry. Modelling effects and boundary conditions are quantified. The good agreement between the experimentally obtained results and previous research demonstrates that the soil–structure interaction during tunnel excavation is well replicated. The experimental procedure provides a framework to quantify how building features affect the response of buildings to tunnelling subsidence.The authors are grateful to EPSRC grant EP/K018221/1 and Crossrail for the financial support

Stepped wedge cluster randomized controlled trial designs: a review of reporting quality and design features

Background The stepped wedge (SW) cluster randomized controlled trial (CRCT) design is being used with increasing frequency. However, there is limited published research on the quality of reporting of SW-CRCTs. We address this issue by conducting a literature review. Methods Medline, Ovid, Web of Knowledge, the Cochrane Library, PsycINFO, the ISRCTN registry, and ClinicalTrials.gov were searched to identify investigations employing the SW-CRCT design up to February 2015. For each included completed study, information was extracted on a selection of criteria, based on the CONSORT extension to CRCTs, to assess the quality of reporting. Results A total of 123 studies were included in our review, of which 39 were completed trial reports. The standard of reporting of SW-CRCTs varied in quality. The percentage of trials reporting each criterion varied to as low as 15.4%, with a median of 66.7%. Conclusions There is much room for improvement in the quality of reporting of SW-CRCTs. This is consistent with recent findings for CRCTs. A CONSORT extension for SW-CRCTs is warranted to standardize the reporting of SW-CRCTs.This work was supported by the Wellcome Trust (grant number 099770/Z/12/Z to MJG); the Medical Research Council (grant number MC_UP_1302/2 to APM) and the National Institute for Health Research Cambridge Biomedical Research Centre (MC_UP_1302/4 to JMSW)

Lightweight Reduced Graphene Oxide@MoS₂ Interlayer as Polysulfide Barrier for High-Performance Lithium–Sulfur Batteries

The further development of lithium–sulfur (Li–S) batteries is limited by the fact that the soluble polysulfide leads to the shuttle effect, thereby reducing the cycle stability and cycle life of the batteries. To address this issue, here a thin and lightweight (8 μm and 0.24 mg cm^–2) reduced graphene oxide@MoS₂ (rGO@MoS₂) interlayer between the cathode and the commercial separator is developed as a polysulfide barrier. The rGO plays the roles of both a polysulfide physical barrier and an additional current collector, while MoS₂ has a high chemical adsorption for polysulfides. The experiments demonstrate that the Li–S cell constructed with an rGO@MoS₂-coated separator shows a high reversible capacity of 1122 mAh g^–1 at 0.2 C, a low capacity fading rate of 0.116% for 500 cycles at 1 C, and an outstanding rate performance (615 mAh g^–1 at 2 C). Such an interlayer is expected to be ideal for lithium–sulfur battery applications because of its excellent electrochemical performance and simple synthesis process

Metallurgy Inspired Formation of Homogeneous Al₂O₃ Coating Layer To Improve the Electrochemical Properties of LiNi_0.8Co_0.1Mn_0.1O₂ Cathode Material

Inspired by the metallurgical process of aluminum production, a controllable and cost-effective Al₂O₃ coating strategy is introduced to improve the surface stability of LiNi_0.8Co_0.1­Mn_0.1O₂. The CO₂ is introduced to NaAlO₂ aqueous solution to generate a weak basic condition that is able to decrease the deposition rate of Al­(OH)₃ and is beneficial to the uniform coating of Al­(OH)₃ on the surface of commercial Ni_0.8Co_0.1­Mn_0.1(OH)₂ precursor. The electrochemical performance of Al₂O₃-coated LiNi_0.8Co_0.1­Mn_0.1O₂ is improved at both ordinary cutoff voltage of 4.3 V and elevated cutoff voltage of 4.5 V. With the optimized Al₂O₃ coating amount (1%), the capacity retention of the material after 60 cycles increases from 90% to 99% at 2.8–4.3 V and from 86% to 99% at 2.8–4.5 V, respectively. The Al₂O₃-coated sample also delivers a better rate capability, maintaining 117 and 131 mA h g^–1 in the voltage ranges 2.8–4.3 and 2.8 V–4.5 V at the current density of 5 C, respectively. The enhanced properties of as-prepared Al₂O₃-coated LiNi_0.8Co_0.1Mn_0.1O₂ are due to the Al₂O₃ coating layer building up a favorable interface, preventing the direct contact between the active material and electrolyte and promoting Li⁺ transmission at the interface

Principal component analysis of fungi communities diversity in rhizosphere soil.

<p>A: Luhe in 2011; B: Luhe in 2012; C: Xinxiang in 2011; D: Xinxiang in 2012. Square: N12-1; Round: Y158. Gray: seeding stage; Green: turngreen stage; Red: grainfilling stage; Yellow: maturing stage. Band position and presence (presence/absence) were used to carry out PCA analyses.</p

PCR-DGGE gel profile of fungi communities used for band sequencing.

<p>The numbers means different bands picked for sequencing.</p

Shannon's index of fungi communities at different growth stages.

<p>Error bars indicate standard errors (n = 4). Different letters above bars denote a statistically significant difference between the means of the fields. A: Luhe; B: Xinxiang. SS: seeding stage; TS: turngreen stage; GS: grainfilling stage; MS: maturing stage.</p

Shannon's index of bacterial communities at different growth stages.

<p>Error bars indicate standard errors (n = 4). Different letters above bars denote a statistically significant difference between the means of the fields. A: Luhe; B: Xinxiang. SS: seeding stage; TS: turngreen stage; GS: grainfilling stage; MS: maturing stage.</p

La solución de conflictos escolares desde la función de orientación del psicopedagogo The resolution of school conflicts from the psychopedagogue orientation role.

Resumen La investigación se desarrolla por la necesidad de gestar en el contexto escolar una influencia educativa direccionada a la construcción de valores para la convivencia, con el soporte del diálogo entre los sujetos. Se sustenta en las manifestaciones observadas en instituciones educativas relativas a desacuerdos, tensiones interpersonales y los enfrentamientos intergrupales que dañan la convivencia en el contexto escolar.  El análisis causal de la situación externa infirió las carencias en los modos de actuación del psicopedagogo desde las habilidades comunicativas y dialógicas para preparar mejor a los maestros en el adecuado empleo de metodologías para la solución de conflictos. Se utilizaron como métodos el análisis y síntesis, el sistémico estructural, la observación, la encuesta, la entrevista y el taller de socialización. La intención se centró en la elaboración de procedimientos para la función de orientación del psicopedagogo a los maestros conducentes a la mediación de los diferentes conflictos que surgen en las instituciones educativas. Los resultados estuvieron en el nivel de satisfacción referido en los test y talleres por los psicopedagogos incorporados al estudio, a partir de contar con una metodología en función de orientar al maestro para la mediación de los conflictos en las relaciones interpersonales en el contexto escolar. Palabras Claves: psicopedagogo, orientaciones educativas, mediación, conflictos escolares. AbstractThe research is a product of the need to create an educational influence in the school context oriented to build values for coexistence, with the support of the dialogue between the subjects. It is based on the manifestations observed in educational institutions related to disagreements, interpersonal tensions and intergroup confrontations that harm the coexistence in the school context. The causal analysis of the external situation demonstrated the deficiencies in the psychopedagogue modes of action from the communicative and dialogic skills to better prepare the teacher in the proper use of methodologies for conflicts solution. Analysis and synthesis, structural systemic, observation, survey, interview and socialization workshops were used as methods. The purpose was to elaborate procedures for the psychopedagogue to work with the teacher in the mediation of the different conflicts arising in educational institutions. The results showed a level of satisfaction on the pedagogues part in relation to tests and workshops conducted in the study since they were provided with a methodology to guide the teacher in the mediation of conflicts in interpersonal relationships in the school context.Keywords: psychopedagogue, educational orientation, mediation, school conflicts

Principal component analysis of bacterial community diversities in rhizosphere soil.

<p>A: Luhe in 2011; B: Luhe in 2012; C: Xinxiang in 2011; D: Xinxiang in 2012. Square: N12-1; Round: Y158. Gray: seeding stage; Green: turngreen stage; Red: grainfilling stage; Yellow: maturing stage. Band position and presence (presence/absence) were used to carry out PCA analyses.</p