A New Species of Grigiotermes (Apicotermitinae, Termitidae) from the Northern Atlantic Forest, Delimited by Morphological and Molecular Data

In this paper, we described a new species of Grigiotermes, G. piassava sp. n., from the Brazilian Atlantic Forest. The imago and worker caste are described, including the gut morphology. The inclusion of the new species in Grigiotermes was based on morphological and DNA data. Apparently, the distribution of the species is limited to the northern region of the Atlantic Forest, located above the São Francisco River, which is considered one of the most threatened sectors of the biome

Rail power conditioner based on indirect AC/DC/AC modular multilevel converter using a three-phase V/V power transformer

This paper presents a rail power conditioner (RPC) system based on an indirect AC/DC/AC modular multilevel converter (MMC) where a V/V power transformer is used to feed the main catenary line and the locomotives. The proposed control strategy for this system has been introduced to guarantee a good compensating performance of negative sequence currents (NSCs) and harmonics on the public grid side. This control strategy has also the ability to achieve balanced and equal voltage between the MMC’s submodules (SMs) capacitors. Simulation results for this RPC based on an indirect MMC are presented in this paper to show the main advantages of using this topology. The results show how the proposed system is able to compensate NSCs and harmonics on the public grid side when the V/V power transformer feeds two unequal load sections.Fundação para a Ciência e Tecnologia (FCT)info:eu-repo/semantics/publishedVersio

Sound and noise in high school gymnasiums

The goal of this research was to characterize the interior acoustics of high schools sports facilities using objective parameters. In situ measurements were done in 68 school gymnasiums in Portugal (Volume from 450 to 16,190 m3 with a median of 4,720 m3) regarding LAeqBN (background noise without gym classes), LAeqPE (ongoing Physical Education classes), RT, and RASTI. The results for LAeqBN were from 30 to 59 dB with a median of 42 dB. For the LAeqPE were found values from 68 to 90 dB with a median of 80 dB. For the RT(500/1k/2k), room values from 2.5 to 8.1 s with a median of 4.8 s, were measured. The room average RASTI values were from 0.26 to 0.54 with a median of 0.34. These sports rooms proved to be highly reverberant, almost without sound absorbing materials, which might be harmful, especially for the PE teachers. The subjective perception of the PE teachers was analyzed through questionnaires where it was verified that they feel most discomfort when it comes for noise conditions. This was supported by the objective results obtained. A multicriteria method to assess the overall acoustic quality of school gymnasiums is presented. Ideal values for those acoustic parameters are presented

O som e o ruído nos jardins do Porto

Este trabalho aborda a paisagem sonora de dez parques e jardins urbanos do Porto, analisando os seus ambientes sonoros através de duas abordagens: avaliação acústica do interior e exterior dos jardins (LAeq, LA10, LA50 e LA90) e por inquérito aos visitantes. Os níveis sonoros no interior dos jardins variaram entre 47 e 61 dB(A). O LAeq no exterior face ao interior variou entre +3 e +19 dB(A). Os jardins mais ruidosos são de menor dimensão e estão localizados em zonas mais centrais da cidade. Apresenta-se uma nova classificação "acústica" de jardins urbanos quanto à sua capacidade de "isolamento" e ao ambiente sonoro. É feita uma comparação com medições feitas em 1990. O inquérito sócio-acústico concluiu que estes jardins são visitados por uma população envelhecida que se encontra habituada/conformada ao tipo de ruído dominante, classificando estes espaços como tranquilos.This work concerns the soundscape of ten urban gardens and parks in Porto, Portugal. It characterizes and analyzes their noise levels through two approaches: acoustic characterization of the inside and outside of the gardens through the parameters LAeq, LA10, LA50 and LA90; socio-acoustic survey to the visitors. The results concluded that the gardens noise levels ranged between 47 and 61 dB(A). The difference between the exterior and the interior LAeq was between +3 and +19 dB. The noisiest gardens are the smaller ones, located near the citys centre. An acoustic classification for gardens/urban parks was proposed regarding their isolation capacity and acoustic ambience. A comparison with the measurements made in 1990 is presented. The socio-acoustic survey concluded that Portos gardens and parks are visited mostly by an elderly population accustomed to the dominant noise, classifying these spaces as pleasant and quiet

Acústica da Mesquita Central de Lisboa

Esta comunicação caracteriza acusticamente a Mesquita Central de Lisboa. Nesta mesquita são analisados a inteligibilidade da palavra e o ruído de fundo associado quer a equipamentos mecânicos quer ao ruído de tráfego. O ruído de fundo foi analisado sem o funcionamento do sistema AVAC, visto este não existir na mesquita. É feita também uma comparação com valores obtidos noutras mesquitas e com igrejas que apresentam volumetria semelhante.This paper presents the acoustical characterization of the Central Mosque in Lisbon. In situ, measurements were done regarding Reverberation Time, RASTI and background noise associated with traffic (this analyzed without the operation of HVAC system, since this does not exist at the mosque). The analysis of the results is shown as a comparison with results in other mosques and Catholic churches that have a similar volume

Transport properties of pristine few-layer black phosphorus by van der Waals passivation in an inert atmosphere

Ultrathin black phosphorus is a two-dimensional semiconductor with a sizeable band gap. Its excellent electronic properties make it attractive for applications in transistor, logic and optoelectronic devices. However, it is also the first widely investigated two-dimensional material to undergo degradation upon exposure to ambient air. Therefore a passivation method is required to study the intrinsic material properties, understand how oxidation affects the physical properties and enable applications of phosphorene. Here we demonstrate that atomically thin graphene and hexagonal boron nitride can be used for passivation of ultrathin black phosphorus. We report that few-layer pristine black phosphorus channels passivated in an inert gas environment, without any prior exposure to air, exhibit greatly improved n-type charge transport resulting in symmetric electron and hole transconductance characteristics.B.O. acknowledges support by the National Research Foundation, Prime Minister's Office, Singapore under its Competitive Research Programme (CRP Award No. NRF-CRP9-2011-3) and the SMF-NUS Research Horizons Award 2009-Phase II. A.H.C.N. acknowledges the NRF-CRP award 'Novel 2D materials with tailored properties: beyond graphene'. The calculations were performed at the GRC computing facilities. A.Z. and D.F.C. acknowledge the NSF grant CHE-1301157. (NRF-CRP9-2011-3 - National Research Foundation, Prime Minister's Office, Singapore under its Competitive Research Programme (CRP); SMF-NUS Research Horizons Award-Phase II; NRF-CRP award 'Novel 2D materials with tailored properties: beyond graphene'; CHE-1301157 - NSF)Published versio

Estudio de la compactación de un Ferralsol manejado con un sistema de no laboreo en Selvíria (MS, Brasil)

No tillage management is widely used by the Brazilian farmers and technicians like a soil conservation system, which reduces the soil losses by water erosion, increasing the infiltrated and stored water in soil, warranting environmental sustainability. No-tillage system does not invert the soil; it causes the creation of a compacted layer. The samples were taken in the agricultural year 2005/2006 in an Oxisoil at Selviria (MS/Brazil). The tillage management in the last 15 years was no-tillage system with crop rotation (maize -Zea mays L./bean - Phaseolus vulgaris L.). The analyzed soil physical properties were bulk density (BS), gravimetric water content (U) and mechanical resistance to penetration (RP) at three depths: 0-0.10 m, 0.10-0.20 m and 0.20-0.30 m. The samples were taken in a mesh with 117 sampled points covering an area of 0.16 ha. It was investigated the existence of compacted soil layer, using the mechanical resistance to penetration to 0.60 m depth with soil water content at field capacity. The data shows low coefficient of variation, except the resistance penetration data. Bulk density and gravimetric water content has a normal distribution. Only resistance to penetration at 0.10-0.20 m depth layer has a normal distribution. The correlation between different properties was low. The bulk density increases with depth; the increase of the values of soil bulk density are consistent with data in other papers, indicating there are not compaction problems for the crop development at the study area. Most of the values of resistance to penetration are lower than 2 MPa, being this value restrictive for root development. The analysis of resistance to penetration profile 0 to 0.60 m shows a compacted layer between 0.20-0.30 m. This compacted layer was caused by the conventional tillage system used at this area before the use of no-tillage system. The soil bulk density has higher values at the upper area, that it shows higher values of soil compaction. Although the values of bulk density and resistance to penetration are high, the area does not show great problems of soil compaction

Oxygen defects in phosphorene

Physical Review Letters114404680