Assessment of daylight in rooms with different architectural features

Results are presented from a parametric study that assessed the amount of daylight in rooms with different architectural features: the orientation, window size and visible glazing transmittance, room depth, external obstruction angle and site. Annual lighting simulations were run in order to understand how the daylight availability within a space changes as a function of the architectural features. A sub-dataset of the full result database is examined in detail for north- and south-facing rooms in Turin, north-west Italy, with a visible glazing transmittance of 70%. Each feature is analysed for its influence on the daylighting conditions. A simple graphical tool is presented to promote an easier reading of the results. This was developed to provide a synthesis of information to the design team. It shows the influence of preliminary design solutions on the amount of indoor daylight. This allows a design team to assess indoor daylighting from the earliest design phases onwards and to determine which combinations of architectural features are able to provide high, acceptable or low daylight levels within a room.     

Statistical Regularization for Identification of Structural Parameters and External Loadings Using State Space Models

A novel numerical approach is presented, in the time domain, to simultaneously identify structural parameters and unmeasured input loadings using incomplete output measurement only. The identification problem is formulated as an optimization process, wherein the objective function is defined as the discrepancy between the measured and the predicted data, and is solved by a damped Gauss‐Newton method. Because the proposed algorithm is a time domain technique, forward analyses are required to obtain predicted system responses so as to compute the discrepancy. Therefore, we propose an input force estimation scheme in the identification process to complete the task of input‐output forward analyses, for the case of output‐only measurement. The relationship between the unknown input loadings and the output measurement is established through a state space model, which basically formulates an ill‐posed least squares problem. A statistical Bayesian inference‐based regularization technique is presented to solve such a least squares problem. Finally, the proposed approach is illustrated by both numerical and experimental examples using output‐only measurements of either acceleration or strain time histories. The results clearly show the robustness and the applicability of the proposed algorithm to simultaneously identify structural parameters and unmeasured input loadings with a high accuracy.     

Hexagrid – hexagonal tube structures for tall buildings: patterns,modeling, and design

This paper provides a first insight on tube configurations based on the hexagonal shape (hexagrid) for tall buildings. The idea is to investigate the mechanical properties of hexagrid to assess their applicability in tall buildings and to compare their potential efficiency to the more popular diagrid systems. For the above purposes, a general homogenization approach has been established for dealing with any structural patterns, and a methodology for characterizing the structural patterns from the mechanical point of view has been developed and specified for hexagrids and diagrids. Then on the basis of a simple stiffness criterion, a design procedure has been proposed and applied to a tall building case study, and several structural solutions (both hexagrids and diagrids) have been designed and assessed by varying the major geometrical parameters of the patterns. Copyright © 2015 John Wiley & Sons, Ltd.     

Mn+Sb2O3 Thermite/Intermetallic Delay Compositions

The binary Mn+Sb₂O₃ pyrotechnic composition was investigated for mining detonator time delay applications. EKVI thermodynamic modelling predicted two maxima in the adiabatic reaction temperature. The local maximum, at a manganese fuel content of ca. 36 wt‐%, corresponds to a pure thermite‐type redox reaction: 3 Mn+Sb₂O₃→3 MnO+2Sb. The overall maximum in the adiabatic reaction temperature (ca. 1640 K), at the fuel‐rich composition of 49 wt‐% Mn, is consistent with the reaction 5 Mn+Sb₂O₃→3 MnO+2 MnSb, i.e. a combination of the standard thermite with an additional exothermic intermetallic reaction. XRD analysis of combustion residues confirmed the formation of MnSb and Mn₂Sb for fuel‐rich compositions. Burn rates were measured using delay elements assembled into commercial detonators. The d₅₀ particle sizes were 23.4 and 0.92 μm for the Mn fuel and Sb₂O₃ oxidant powders, respectively. The delay elements comprised rolled lead tubes with a length of 44 mm and an outer diameter of 6.4 mm. The rolling action compacted the pyrotechnic compositions to 74 ± 2 % theoretical maximum density. The burning rate increased linearly from 4.2 to 9.4 mm s⁻¹ over the composition range 25–50 wt‐% Mn.     

Integration of InGaP/GaAs/Ge triple‐junction solar cells on deeply patterned silicon substrates

We report preliminary results on InGaP/InGaAs/Ge photovoltaic cells for concentrated terrestrial applications, monolithically integrated on engineered Si(001) substrates. Cells deposited on planar Ge/Si(001) epilayers, grown by plasma‐enhanced chemical vapor deposition, provide good efficiency and spectral response, despite the small thickness of the Ge epilayers and a threading dislocation density as large as 10⁷/cm². The presence of microcracks generated by the thermal misfit is compensated by a dense collection grid that avoids insulated areas. In order to avoid the excessive shadowing introduced by the use of a dense grid, the crack density needs to be lowered. Here, we show that deep patterning of the Si substrate in blocks can be an option, provided that a continuous Ge layer is formed at the top, and it is suitably planarized before the metalorganic chemical vapor deposition. The crack density is effectively decreased, despite that the efficiency is also lowered with respect to unpatterned devices. The reasons of this efficiency reduction are discussed, and a strategy for improvement is proposed and explored. Full morphological analysis of the coalesced Ge blocks is reported, and the final devices are tested under concentrated AM1.5D spectrum. Copyright © 2016 John Wiley & Sons, Ltd.     

Probiotic-Induced Tolerogenic Dendritic Cells: A Novel Therapy for Inflammatory Bowel Disease?

Inflammatory bowel diseases (IBDs) are immune-mediated, chronic relapsing diseases with a rising prevalence worldwide in both adult and pediatric populations. Treatment options for immune-mediated diseases, including IBDs, are traditional steroids, immunomodulators, and biologics, none of which are capable of inducing long-lasting remission in all patients. Dendritic cells (DCs) play a fundamental role in inducing tolerance and regulating T cells and their tolerogenic functions. Hence, modulation of intestinal mucosal immunity by DCs could provide a novel, additional tool for the treatment of IBD. Recent evidence indicates that probiotic bacteria might impact immunomodulation both in vitro and in vivo by regulating DCs’ maturation and producing tolerogenic DCs (tolDCs) which, in turn, might dampen inflammation. In this review, we will discuss this evidence and the mechanisms of action of probiotics and their metabolites in inducing tolDCs in IBDs and some conditions associated with them.     

Rapid Detection and Suppression of Mining Equipment Cab Fires

The National Institute for Occupational Safety and Health (NIOSH/PRL) conducted a series of large-scale experiments to evaluate the effectiveness of optical flame detectors, photoelectric smoke detectors, and combined ionization and photoelectric smoke detectors for rapidly detecting mining equipment cab fires. The detector alarm times were then used to trigger the discharge of a fire inerting system inside the cab to suppress cab material fires. This paper discusses the types of fire detectors tested, the experiments that were conducted, and the results that were obtained. Conclusions are that rapid detection of equipment cab fires can be achieved to trigger the discharge of a fire inerting system inside the cab to protect the operator in the cab.     

Nanomaterials for environmental studies: Classification, reference material issues, and strategies for physico-chemical characterisation

NanoImpactNet is a European Commission Framework Programme 7 (FP7) funded project that provides a forum for the discussion of current opinions on nanomaterials in relation to human and environmental issues. In September 2008, in Zurich, a NanoImpactNet environmental workshop focused on three key questions:

1.

What properties should be characterised for nanomaterials used in environmental and ecotoxicology studies?

2.

What reference materials should be developed for use in environmental and ecotoxicological studies?

3.

Is it possible to group different nanomaterials into categories for consideration in environmental studies?

Such questions have been, at least partially, addressed by other projects/workshops especially in relation to human health effects. Such projects provide a useful basis on which this workshop was based, but in this particular case these questions were reformulated in order to focus specifically on environmental studies. The workshop participants, through a series of discussion and reflection sessions, generated the conclusions listed below.The physicochemical characterisation information identified as important for environmental studies included measures of aggregation/agglomeration/dispersability, size, dissolution (solubility), surface area, surface charge, surface chemistry/composition, with the assumption that chemical composition would already be known.There is a need to have test materials for ecotoxicology, and several substances are potentially useful, including TiO₂ nanoparticles, polystyrene beads labelled with fluorescent dyes, and silver nanoparticles. Some of these test materials could then be developed into certified reference materials over time.No clear consensus was reached regarding the classification of nanomaterials into categories to aid environmental studies, except that a chemistry-based classification system was a reasonable starting point, with some modifications. It was suggested, that additional work may be required to derive criteria that can be used to generate such categories, that would also include aspects of the material structure and physical behaviour.     

Organochlorine pesticides in colostrums in case of normal and preterm labor (IASI, Romania)

Assessment of organochlorine pesticides (OCPs) in human body is important for human health because they have weak estrogenic or antiestrogenic effects and are considered endocrine disrupters. We used colostrum of women as indicator for levels of OCPs in human body for mothers with normal and preterm labor from eastern part of Romania. Sixty- three samples of colostrum were extracted by solid-phase extraction. Analyses were carried out using gas chromatography coupled to mass spectrometry (GC-MS). OCPs have been detected in all samples, with p,p’-dichlorodiphenyldichloroethylene (p,p’-DDE) and γ-hexachlorocyclohexane (γ-HCH) being at the highest concentrations. Of the organochlorines measured in clostrum samples from women in preterm labor, median levels of DDTs (470 ng/g) and HCHs (99 ng/g) were higher than for the same compounds from women in normal labor (median of DDTs = 268 ng/g and median of HCHs = 96 ng/g). Normal labor had higher median concentrations of HCB (19.5 ng/g) versus preterm labor (14 ng/g). Statistical data show high Spearman correlation coefficients between various OCPs. We found a good correlation between α-, γ-, β- and δ- HCH isomers (p < 0.001) for both normal and preterm labor. The most abundant target compound was p,p’-DDE (median value 96 ng/g, and 137 ng/g for mother with normal and preterm labor, respectively) in all colostrum samples. The estimated daily intakes of HCHs by infants exceeded corresponding Health Canada guidelines.