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This study aims to investigate the influence of weather exposure on the physical and mechanical characteristics of rHDPE matriced composites reinforced with zalacca midrib fibers. The specimens were fabricated using the compression molding method into 3 variations which include the neat rHDPE as control as well as the untreated and alkaline-treated zalacca fiber-reinforced rHDPE composites at 30 % vf. Moreover, the weathering exposure was conducted under a tropical climate for 6 months after which all the specimens became chalky and showed significant changes in color. The FTIR results indicated that carbonyl groups of rHDPE emerged due to the weathering exposure while the thermogravimetry test showed no significant change in thermal stability. It was also discovered that their flexural and impact strength were enhanced by the alkaline treatment but the effect diminished after weathering. The micrograph observation showed some gaps between fibers and matrix, breakage of the fibers and matrix bonds, and cracks on matrix around the fibers. Furthermore, the fracture of the neat rHDPE was observed to be more brittle after exposure and this means the neat rHDPE and rHDPE-ZF composites are suitable for indoor applications but not recommended for outdoor uses.

Structure B is an archaeological structure from the post-classic period of the Mexica culture located within the archaeological site of Templo Mayor in Mexico City. The various alteration dynamics caused by its exposure to the weather have generated severe conservation problems in the stuccos that cover the reliefs of the stone skulls of Structure B. Since the alteration effects are mainly due to the crystallization of salts, the absorption of direct humidity because of stagnation of water and the impact of rainwater, the use of sacrificial layers is presented as a measure for the long-term conservation of the stuccos. This investigation proposes a methodological framework for the elaboration of diverse models of sacrificial layers, as well as for their qualitative evaluation after submitting them to resistance tests that imitate the environmental dynamics to which the structure is subjected, in order to design a suitable sacrificial layer for a given structure and context. Received: 2018-11-30Revised: 2019-4-5Accepted: 2019-4-7Online: 2019-5-14Publication: 2019-5-14, A Estrutura B é uma estrutura arqueológica da cultura asteca, do período pós-clássico, localizada dentro do complexo arqueológico Templo Mayor na Cidade do México. A sua exposição às condições climatéricas locais tem originado vários problemas ao nível da conservação dos estuques que cobrem os relevos dos crânios de pedra da Estrutura B. Dado que os efeitos de alteração são causados maioritariamente pela cristalização de sais, pela absorção directa de água estagnada e pelo impacto da precipitação, o uso de camadas sacrificiais é aqui apresentado como uma medida para a conservação a longo prazo destes estuques. Assim, este trabalho propõe uma metodologia não só para a elaboração de diversos modelos de camadas sacrificiais, mas também para a avaliação qualitativa desses mesmos modelos, através da realização de ensaios de resistência que visam simular as condições climatéricas que podem afectar a estrutura em questão. Esta metodologia permite desta forma, conceber camadas sacrificiais específicas para uma determinada estrutura e respectivo contexto. Recebido: 2018-11-30Revisto: 2019-4-5Aceite: 2019-4-7Online: 2019-5-14Publicação: 2019-5-14

Water is one of the most significant factors for the durability of wood. A common solution is to use a coating to protect and maintain low water content. However, little knowledge exists how the underlying wood substrate affects the water sorption of coated wood. Therefore, the liquid water absorption of coated and uncoated Norway spruce heartwood and sapwood with a variety of densities was measured by letting the panels float freely in the water. The effect of one year weathering of the coatings was also included. Coated heartwood and sapwood had no difference in water absorption in opposite to uncoated spruce. The influence of heartwood and sapwood seemed to have limited impact when a coating hindered the presence of free water. Wood density had a positive effect on the absorption of coated wood, i.e. low absorption for low-density samples, in opposite to uncoated samples. Low-density characteristic also contributed to a lower increase of water absorption after weather degradation, for samples with water-borne coatings. Natural weathering enhanced the effect of wood characteristics on coated samples, likely by an increase of coating permeability.

The environmental drivers and mechanisms of influenza dynamics remain unclear. The recent development of influenza surveillance--particularly the emergence of digital epidemiology--provides an opportunity to further understand this puzzle as an area within applied human biometeorology. This paper investigates the short-term weather effects on human influenza activity at a synoptic scale during cold seasons. Using 10 years (2005-2014) of municipal level influenza surveillance data (an adjustment of the Google Flu Trends estimation from the Centers for Disease Control's virologic surveillance data) and daily spatial synoptic classification weather types, we explore and compare the effects of weather exposure on the influenza infection incidences in 79 cities across the USA. We find that during the cold seasons the presence of the polar [i.e., dry polar (DP) and moist polar (MP)] weather types is significantly associated with increasing influenza likelihood in 62 and 68% of the studied cities, respectively, while the presence of tropical [i.e., dry tropical (DT) and moist tropical (MT)] weather types is associated with a significantly decreasing occurrence of influenza in 56 and 43% of the cities, respectively. The MP and the DP weather types exhibit similar close positive correlations with influenza infection incidences, indicating that both cold-dry and cold-moist air provide favorable conditions for the occurrence of influenza in the cold seasons. Additionally, when tropical weather types are present, the humid (MT) and the dry (DT) weather types have similar strong impacts to inhibit the occurrence of influenza. These findings suggest that temperature is a more dominating atmospheric factor than moisture that impacts the occurrences of influenza in cold seasons.

Ceramic materials such as bricks and tiles used in civil construction, may eventually be exposed to weather conditions and undergo degradation with time. Although this degradation has been studied in common plain ceramics, it has not yet been investigated in clay ceramics incorporated with ornamental stone residues. In the present work the degradation suffered by clay ceramics incorporated with 5 and 10 wt % of a granite residue under weathering for 6, 8 and 10 months was evaluated. The incorporated and plain ceramics were fired at temperatures of 500, 700 and 900°C. The linear dimensional changes were measured just after firing as well as after 180, 240 and 300 days, respectively, 6, 8 and 10 months. In general, the linear dimensions tend to increase with time and firing temperature. The role of absorbed water on these changes is discussed.

Recent evidence suggests that weather exposure influences exam performance. Using an administrative dataset of Brazil’s college entrance exam (Exame Nacional do Ensino Medio, known as ENEM) from 2012 to 2016, we find that temperature has a negligible impact on test performance, with a 1 °C increase in dry bulb temperature improving the z-score by three-thousandths of a standard deviation. Humidity and rainfall also have limited effects on test performance. These findings are robust to various alternative specifications. In addition, there are no meaningful heterogeneities by test subjects, gender, student score quartiles, or race. Our findings suggest that the weather effect on high-stakes test performance is neither substantive nor conclusive.

Extreme weather is known to cause failure bunching in electrical transmission systems. However, protection systems can also contribute to the worsening of the system state through various failure modes&mdash, spontaneous, missing or unwanted operation. The latter two types of failures only occur when an initial failure has happened, and thus are more likely to happen when the probability of failure of transmission lines is high, such as in an extreme weather scenario. This causes an exacerbation of failure bunching effects, increasing the risk of blackouts, or High Impact Low Probability (HILP) events. This paper describes a method to model transmission line failure rates, considering both protection system reliability and extreme weather exposure. A case study is presented using the IEEE 24 bus Reliability Test System (RTS) test system. The case study, using both an approximate method as well as a time-series approach to calculate reliability indices, demonstrates both a compact generalization of including protection system failures in reliability analysis, as well as the interaction between weather exposure and protection system failures and its impact on power system reliability indices. The results show that the inclusion of protection system failures can have a large impact on the estimated occurrence of higher order contingencies for adjacent lines, especially for lines with correlated weather exposure.

Extreme weather is known to cause failure bunching in the electrical transmission system. However, protection systems can also contribute to the worsening of the system state through spontaneous, missing or unwanted operation of the protection system. The latter two types of failures only occur when an initial failure has happened, and thus is more likely to happen when the probability of failure of transmission lines is high, such as in an extreme weather scenario. This causes an exacerbation of failure bunching effects, increasing the risk of blackouts, or High Impact Low Probability (HILP) events. This paper describes a method to model transmission line failure rates, considering both protection system reliability and extreme weather exposure. A sample case study is presented using the 6 bus RBTS test-system. The case study, using both an approximate method as well as a time-series approach to calculate reliability indices, demonstrates both a compact generalization of including protection system failures in reliability analysis, as well as the interaction between weather exposure and protection system failures and its impact on power system reliability indices. The results show that the inclusion of protection system failures can have a large impact on the estimated occurrence of higher order contingencies for adjacent lines, especially in periods of high weather exposure. © 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.

Weather affects the daily lives of individuals. However, its health effects have not been fully elucidated. It may lead to physical symptoms and/or influence mental health. Thus, we evaluated the association between weather parameters and various ailments. We used daily reports on health symptoms from 4548 individuals followed for one month in October of 2013, randomly sampled from the entirety of Japan. Weather variables from the monitoring station located closest to the participants were used as weather exposure. Logistic mixed effects model with a random intercept for each individual was applied to evaluate the effect of temperature and humidity on physical symptoms. Stratified analyses were conducted to compare weather effects by sex and age group. The lag day effects were also assessed. Joint pain was associated with higher temperature (1.87%, 95% CI = 1.15 to 2.59) and humidity (1.38%, 95% CI = 0.78 to 2.00). Headaches was increased by 0.56% (95% CI = &minus, 0.55 to 1.77) per 1 &deg, C increase in the maximum temperature and by 1.35% per 1 &deg, C increase in dew point. Weather was associated with various physical symptoms. Women seem to be more sensitive to weather conditions in association with physical symptoms, especially higher humidity and lower temperature.

Attract-and-kill bait stations and olive foliage sprayed with insecticidal bait spray and exposed to 0–4 weeks of weather were evaluated for efficacy by olive fruit fly, Bactrocera oleae (Rossi), adult mortality. Mortality in greenhouse cage tests was significantly higher after three days than one day of exposure to non-weathered bait spray on bait stations and foliage, and on bait stations exposed to weather for three weeks. Mortality increased with an increase in insect exposure time, and decreased as bait spray weather exposure increased. Mortality was higher on bait stations than on olive foliage, and treated foliage showed little toxicity after 4 weeks in weather. In a commercial orchard, bait station efficacy was determined by captures of adults on yellow panel traps. Day temperatures were slightly higher on the underside of the station than top from 2 May to 10 July, similar on the top and underside 11 July to 7 August, and slightly lower on the underside from 8 August to 4 September. Fruit length increased from 0.4 on 16 May to 3 cm on 24 September and on 30 May attained 1 cm, the minimum size to produce one adult. No larvae or adults emerged from collected fruit. More adults were captured in an untreated row than a row with bait stations until 22 August and significantly so for the period ending on 11 July. Maximum adult captures occurred during 2 weeks prior to 19 September. Attract-and-kill bait stations would help reduce insecticidal applications and table olive production costs.

The mechanical properties of two linear low density and low density polyethylenes containing a pro-oxidant additive were monitored during accelerated aging (60 °C in a convection oven) and weather exposure. Tearing tests (trouser) were performed for the first time in polyethylenes subjected to oxo-degradation revealing a transition from an extensible to a non-extensible material, at exposure times when standard tensile tests were not able to detect any changes in the materials. The essential work of fracture (EWF) technique was also applied and the results were in agreement with those of trouser tests. The specific essential work of fracture first increased with exposure time until the sample experienced a transition to a less ductile state where EWF was no longer applicable. EWF and trouser tear tests were more sensitive detecting the onset of degradation probably because they employ notched specimens that impose more critical stress concentration conditions than conventional tensile tests.

Resumo Por mais de um seculo o monumento a Anita e Giuseppe Garibaldi, obra de Filadelfo Simi, escultor fiorentino, executada em marmore de Carrara, encontra-se exposto a ceu aberto na Praca Garibaldi, em Porto Alegre. Seu precario estado de conservacao levou a Coordenacao da Memoria Cultural a contratar, em 2014, servicos tecnicos especializados para desenvolvimento de projeto e realizacao de intervencoes para sua conservacao. Partindo da premissa de que e necessario compreender a obra para que um projeto de recuperacao tenha exito, foram realizados levantamentos do material constituinte, ensaios de caracterizacao tecnologica e medicoes de indices fisicos e geofisicos que forneceram dados para o diagnostico. Buscava-se entender as causas e efeitos provocados pela exposicao ao tempo, assim como as sucessivas acoes humanas que, incidindo sobre o monumento, interferiram em seu estado de conservacao, na materia e, como consequencia em sua imagem. Da mesma forma, procurou-se definir diretrizes e criterios de intervencao que foram utilizados na primeira etapa realizada. Palavras Chave: marmore, caracterizacao, diagnostico Abstract MONUMENT TO ANITA AND GIUSEPPE GARIBALDI: DIAGNOSIS AND TREATMENT. For over a century the Monument to Anita and Giuseppe Garibaldi, a work of Filadelfo Simi, a Florentine sculptor, executed in Carrara marble, is exposed to open air at Garibaldi Square, in Porto Alegre. Its precarious state of conservation led the department in charge Coordination of Cultural Memory to contract in 2014 specialized technical services for project development and interventions for its conservation. Considering the premise that it is necessary to understand the work for a recovery project to succeed, assessments of the constituent materials were conducted, including technological characterization tests and measurements of physical and geophysical indexes that provided data for the diagnosis. These sought to understand the causes and effects of weather exposure as well as successive human actions, which interfered in its conservation, and as a result on its appearance. Also, we define guidelines and intervention criteria that were used in the first step performed. Keywords: marble, characterization, diagnosis

Broadcasts of hydramethylnon, S-methoprene, and metaflumizone baits, metaflumizone spray, and hot water drenching were evaluated for their efficacy against the little fire ant, Wasmannia auropunctata (Roger), in potted nursery plants. Two applications one month apart of either a bait containing 0.365% hydramethylnon and 0.25% S-methoprene (Extinguish Plus) or a spray containing 24% metaflumizone (BAS 320 I 240 SC) reduced foraging worker numbers by >97% as compared with untreated controls. The persistence of weather-exposed metaflumizone (0.063%) bait was also evaluated: bait applied fresh or after 7 days of weather exposure resulted in >98% ant mortality; bait exposed to weather for 14 d before application still achieved >90% mortality. In vitro submersion of W. auropunctata in 45°C water for 10 min resulted in >99% mortality as compared with 28.9% mortality from submersion in ambient temperature water (26°C) for 12 min. When W. auropunctata -infested potted plants were drenched with hot water (...

This study investigates the motivations, concerns and obstacles regarding the use of weather derivatives in the winter tourism industry. The findings from the interviews with 61 ski lift operators in Austria indicate that while the majority of operators are aware of weather risks and report substantial weather exposure, using weather derivatives as a means of offsetting potential loss is rarely considered. This is primarily due to a lack of awareness and knowledge, but on becoming aware of the availability of such instruments ski lift operators express interest in their possible use. The task is thus to increase awareness, knowledge and support for the ski lift operators with reference to the use of weather derivatives.

An estimation of moisture loading severity for building components in Greece was attempted. Annual driving rain indices were calculated for 31 stations spread all over the country, based on the average annual rainfall and wind speed values derived from data, published by Hellenic National Meteorological Service. The analysis revealed that the majority of the locations are sheltered from driving rain. A driving rain map for Greece was produced. A second set of annual driving rain indices were calculated for these sites, based on average monthly data. The relationship between these two sets of indices for the 31 locations was best approximated by a hyperbolic function. Thessaloniki, a city in northern Greece, was further studied using average annual and daily data provided by the Institute of Meteorology and Climatology, A.U.Th. For Thessaloniki, the exposure estimated from daily data was bigger than the one resulting from annual data. Finally, a moisture index for the comparison of building components' exposure to moisture, with the drying potential also being considered, was calculated for the 31 sites studied and a ranking of these sites' climates in terms of moisture loading on buildings was obtained. The drying potential's contribution to this ranking is very important.

With more interest in using woody biomass as an energy resource, the John Deere 1490D slash bundler is gaining in popularity for extracting logging residues from harvest sites. In the Mid-South, the winters are wet, and extraction from the forest is limited; therefore, energy facilities store up to 6 months of material to survive the reduced logging output. This study's goal was to determine if the slash bundles would be a good storage medium for wet winter storage. Five bundles from each of four different harvest sites were placed in open storage in southeastern Arkansas during July and inspected monthly through April. After the April inspection, a 5 percent sample was cut from each bundle and analyzed for British thermal unit (Btu) value per ovendry pound. The results indicated that the bundles would maintain their structural integrity through winter storage and that the Btu value per ovendry pound after the exposure was only slightly less than the average value used for wood (8,376 compared with 8,600). This would indicate that slash bundles would be a very good medium for storing these residues during the winter months.

Les différentes zones d’un ouvrage d’art routier sont étudiées en fonction de leur degré d’exposition au microclimat environnant. Les conditions climatiques provenant de stations météorologiques et la cinétique des véhicules permettent de définir des zones d’exposition aux produits salants et au climat. Une division judicieuse d’un ouvrage en éléments structuraux en fonction de son exposition permet de prendre en considération l’importante variabilité spatiale et de définir des zones de sensibilité équivalente face aux détériorations. Sur la base de stations météorologiques suisses, d’un monitoring d’un ouvrage d’art routier, d’enquêtes auprès des autorités publiques, de mesures ponctuelles in situ et de recherches bibliographiques, cet article met en exergue le microclimat des structures de manière précise. Cette approche permet de définir les différentes zones d’exposition des ouvrages, à savoir les zones de brouillard salin, d’éclaboussures et de stagnation d’eau et de définir l’importance du microclimat en vue de prédire l’évolution des détériorations des structures.

RESUMO Este estudo teve por objetivo avaliar a ação do tempo de exposição ao intemperismo artificial na cor de lâminas de madeiras de teca tratadas com produtos de acabamento. Amostras que receberam 2 tipos de produto, a seladora e o stain, mais as testemunhas, sem acabamento. O experimento foi instalado no delineamento inteiramente casualizado, com 3 tratamentos e 4 repetições. As lâminas ficaram expostas ao simulador QUV-Acelerated Weathering Teste, por 7 períodos, de: 6, 12, 24, 48, 96, 192 e 384 horas. Após cada período de intemperismo foram feitas medições das cores, com espectrofotômetro COLOR EYe XTH. As variáveis cromáticas avaliadas foram: L*, a*, b*, C e h*. Ao final do estudo pôde-se concluir que as lâminas de madeira de teca sofreram alterações em sua cor com o passar do tempo de exposição e que o stain apresentou maior eficiência na conservação da cor da madeira. ABSTRACT This study aims to evaluate the effects of weather exposure to artificial weathering in the color of teak wood veneer treated with finishing products. The samples received 2 types of products, the sealer and the stain, plus witnesses, unfinished. The experiment was conducted in a completely randomized design with 3 treatments and 4 replications. Slides were exposed to QUV-Accelerated Weathering Test simulator for 7 periods as follow: 6, 12, 24, 48, 96, 192 and 384 hours. Color measurements were made after each period of weathering using the spectrophotometer Color Eye XTH. The chromatic variables evaluated were: L *, a *, b *, C * and h*. The study concluded that the teak wood veneer had color alterations with the exposure time and the stain was more efficient in preserving the wood color.

This paper reflects on the ergonomical criteria for a humane working atmosphere in industrial buildings while respecting and paying close attention to the physical, mental, and stressful demands of the work environment. It describes effective construction codes and standards of practice and their importance in ensuring a safe environment for working people. Also addressed are the objectives for a productive work environment and its organization. The paper considers the significance of a proper working environment, sufficient training in regards to weather exposure, the use of dangerous working materials, the use of proper ventilation, climate, and lighting to ensure that the productivity of the enterprise is met with common goals shared between employer and employee. The connection between the legal foundation and the design of industrial construction is the focus of this paper. It shows that the planning and executive persons are obliged to observe the relevant construction laws and regulations including standards and codes of practice focusing on the health and safety of the worker. Additionally discussed are the possible solutions and consequences for development in the production, constructional and ergonomical fields of design.

This paper presents results from an investigation of the suitability of the exposure coefficient as defined in ISO 4355 “Bases for design of structures—Determination of snow loads on roofs”, based on thorough analyses of weather data from 389 weather stations in Norway for the reference 30-year period 1961–1990. First, the background of the exposure coefficient is examined. Historical field investigations of snow loads on roofs are also evaluated. Next, values for the exposure coefficients in Norway are calculated according to ISO 4355. Finally, possible approaches aiming at improving calculations of wind exposure on roof snow loads are suggested. It is shown that the exposure coefficient as defined in ISO 4355 does not reflect the actual effects of wind exposure on roof snow loads in Norway, the main reasons being oversimplifications in the definition of the coefficient and the extreme variations of the climate in Norway. The definition is based on coarse simplifications of snow transport theories, and must be revised and improved to serve as an applicable tool for calculations of design snow loads on roofs in Norway.

The disintegrative process of freezing and thawing of porous, mineral materials represents a significant challenge in the design and construction of building enclosures. In this paper, we present a simple method for assessing the relative potential of a climate to accelerate frost decay based on multi-year records of daily air temperatures and rainfall, with special emphasis on masonry. Distributions of 4-day rainfall prior to days with freezing events provide quantitative information on the geographically dependant frost decay risk in porous, mineral building materials in a given climate. Data from 168 weather stations in Norway are analysed, using weather data from the reference 30-year period 1961–1990.

Over the past decade, the method of choice for calculating driving rain loads from weather data has been to use long series of hourly wind and rainfall data, preferably of 20 or 30 years. In an earlier article, we presented an alternative method for driving rain mapping in areas where long records of hourly weather data are not available, e.g. in Norway. In this method, annual directional driving rain loads are calculated based on present weather observations and knowledge of average annual rainfall. In this paper, we compare the two methods using data from three weather stations in Great Britain for the 20-year period 1976–1995. The results suggest that the present weather observation method yields comparable results to the hourly wind and rainfall method, and therefore can be used as a substitute in areas where sufficiently long series of hourly values of wind and rainfall amounts are not currently available.

The influence of thermomechanical treatment on the structure and properties of a Nb bearing weather resistant steel has been studied. The steel contains 0.11% C, 0.024% Nb, 0.3% Ni and 0.45% Cr and Cu each. It has been found that the YS, UTS and hardness of rolled steel increase with increasing soaking temperature. However, increasing the rolling deformation results in an increase in YS but not in UTS markedly. Rolling 25% at 800, 900 or 1000 °C after soaking at 1100 °C results in much lower YS. The YS is also lower due to 50% reduction at 1000 °C. The optical microstructure after 1000 °C soaking is ferrite–pearlite at 900 and 800 °C rolling temperatures where as in addition to ferrite–pearlite, granular bainite is also observed after rolling at 740 °C. After soaking at 1100 °C, considerable amount of granular bainite has formed for all the rolling temperatures. The TEM micrographs, after 1000 °C soaking, show ferrite and pearlite at 740–900 °C rolling temperatures. However, the dislocation density in ferrite at lower rolling temperatures (800 and 740 °C) is higher. On the other hand, presence of considerable amount of martensite–austenite (M/A) constituent along with high dislocation density ferrite is taken as an indication of formation of granular bainite in addition to ferrite and pearlite after soaking at 1100 °C and rolling. For controlled rolling to be effective, higher soaking temperature (≥1100 °C), lower rolling temperatures (∼800 °C) and higher rolling reduction (≥50%) are recommended to take maximum advantage of the Nb microalloying addition.

Concrete specimens weathered for over a decade in the moderate Belgian climate, showing a black organic outer layer that mainly consisted of lichens, were cleaned with a new biological technique. A mixture of sulphur oxidising bacteria of the genusThiobacillus supplemented with an appropriate nutrient was applied to a fouled concrete surface, either by sprinkling or by submersion. The aim was to remove the fouled layer in such a way that the surface is uniformly cleaned. The general effect of the technique was evaluated by colorimetry and microscopy. Two sets of weathered concrete specimens, containing blast furnace slag cement or ordinary portland cement, were investigated. The effectiveness of the technique depended on the cement type of the concrete specimens. The effect on the ordinary portland cement concrete specimens was in some cases up to a factor 2 stronger than the result on the blast furnace slag cement specimens. The sprinkling treatment was about 50% as effective as the submersion treatment but was very promising in the case of in situ acidification. A side effect was the formation of a gypsum layer on some of the specimens, resulting in a whiter colour.

Moisture dynamics and durability during weather exposure as affected by origin and production method were studied for nine years on 113 untreated spruce samples. The moisture content was measured on 67 occasions. The weight loss was determined for each sample at the end of the sampling period. The most important factors, affecting both moisture content and weight loss, were origin and drying technique. The samples originating from central Sweden had the best durability, followed by the southern stand, while the northern stand had the lowest durability in terms of weight loss. Air-drying had a negative impact on the performance of samples from all three stands, but to different degrees. Samples from the northern stand were most sensitive to air-drying, in terms of both weight loss and moisture content, followed by the southern stand, while the central stand was least sensitive. Why the samples from the northern stand were more sensitive to air-drying and showed the largest weight losses is unknown; it can only be suggested that the origin of the wood can be of importance for the durability.

Summary Moisture dynamics in wood during weather exposure as affected by species, origin, production method and painting system were studied for nine years on 170 samples. The moisture content (MC, by dry base) was measured on 67 occasions. Principal component analysis was used for data reduction and pattern recognition. The investigation included two species; Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies L. (Karst)), and showed that the painting method affected the moisture dynamics most. In addition, species and type of wood were important factors, and for pine sapwood also the production method used had an influence on the moisture dynamics. Heartwood of pine had a stable development with low MC throughout the experimental time, regardless of surface treatment or handling method. The pine sapwood samples, on the other hand, had higher average MC and much faster dynamics. For painted and endsealed pine sapwood samples, the drying method was not significant for the MC dynamics, but water storage led to a higher and faster moisture uptake than for samples that were not water-stored. For untreated pine sapwood samples, air-drying led to the highest and fastest moisture uptake, but on the whole this group had unacceptably high moisture uptake. The spruce samples showed very different behaviour depending on whether they were surface treated or not. Painted and endsealed spruce led to two distinct groups, one with moisture dynamics similar to pine heartwood and one with very high moisture uptake and large spread more similar to pine sapwood. Most untreated spruce samples had moisture dynamics comparable to those of pine heartwood.

In 1994 a large scale demonstration project was started in the Netherlands, with the aim of studying the performance of (less polluting) coating systems. In the project 66 paint systems (water-borne acrylics, high solids and traditional solvent-based alkyds) were applied to wooden window components of 66 housing complexes. Also the project contains field exposure and laboratory tests. The variables considered were the type of wood, details of the element, pre-treatment, colour, application conditions and environmental location. Important aspects for evaluation were durability and VOC content of the paint system. The practical performance was assessed each year, and each time on hundreds of window frames, gloss, moisture content, chalking, cracking, flaking, blistering and defects of the elements were measured.

Elastomeric coatings protect building facades and flat roofs from moisture and weather exposure. As a drawback, these coatings are prone to dirt-pickup due to the low glass transition temperature of the used polymeric binders. Strategies to overcome this enhanced soiling tendency are discussed, and the results of laboratory and outdoor soiling tests are compared. A novel method for the assessment of wet soiling tendency is presented.

Automotive coatings continue to evolve rapidly in order to reduce the environmental impact of coating operations and to meet rising customer expectations for appearance and performance. The anticipated changes in chemistry, together with improved appearance retention and the need to respond rapidly to customer desires, have placed new challenges on weathering protocols. This paper discusses these issues and describes several methodologies that are likely to be part of the next generation of accelerated testing protocols. Of critical importance is the need to understand and minimize where possible sources of variability in testing that can lead to uncertain results and increased risk of failure in service.

In the process of service life prediction or estimation of building and construction components and materials, data of the prevailing exposure environment, (the conditions at and around a building or construction) is required. However, most environmental data is measured by and available from meteorological and air quality research communities. This data is collected at macro and meso levels, some distance from the object studied, and raises the need to transform data in order to describe the specific, local conditions adjacent to that object. To estimate levels of degradation agents in the exposure environment, especially those close to the building or construction at local and micro levels have to be considered. This paper will show and discuss useful environmental data sources, and how to transform such data by means of available distribution models. Lorsqu'il s'agit de faire des previsions ou des estimations de duree de vie de bâtiments ainsi que de composants et materiaux de construction, il faut dis...

Previous studies of the effect of preweathering of wood (weathering of wood prior to painting) on subsequent paint performance have not linked short periods of preweathering (weeks) to paint service life. To examine the link between preweathering and paint service life, we analyzed paint performance (cracking and flaking) after 14 years outside on boards that were preweathered for various amounts of time. We then compared our results with previous results from paint adhesion tests of similar boards that were also preweathered for the same amount of time. There was a direct correlation between the amount of time the siding was preweathered and the long-term performance of paint. Paint on wood preweathered for 16 weeks began to fail after just three years. Paint on wood preweathered for shorter periods lasted longer, but even those boards that were preweathered for as little as one week showed paint failure earlier than boards that were not preweathered. There was also good correlation between paint adhesive strength results from the previous study and outdoor paint performance results from this study, showing that loss of paint adhesion may be linked to paint performance in outdoor field tests.

Automotive coatings are expected to retain a good scratch resistance over years of service. On the other hand, scratches once arisen should disappear by reflow or should not become more visible during further use of the car. These expectations are a challenge to the paint manufacturer and are not easy to fulfil as our work will show. Seven car coatings were examined, each with different PU clearcoats. The coatings were treated under artificial weathering conditions before and after the scratch test. Scratching was carried out using laboratory car wash and Nano Scratch techniques. In comparison to other essential coating properties measured, the scratch and mar resistance was mainly affected by pre-weathering. Alterations in reflow behaviour, shape and size of single scratches were observed during post-weathering which included partly acid precipitation.

The correlation between accelerated lightfastness testing and indoor exposure in softwood discoloration was evaluated. The discoloration of softwood exposed to indoor environments was simulated by using an accelerated lightfastness tester equipped with UVA-351 lamps. The trends of the discoloration of three species of softwood (western hemlock, China fir, Japanese cedar) in the accelerated lightfastness testing were similar to those in the indoor exposure test. Bathochromic effects occurred in the spectral reflectance curves of wood with increase in exposure time, and consequently, its color turned yellowish-red. Using the acceleration shift factor (ASF), we could obtain a correlation between accelerated lightfastness testing and indoor exposure. Results from the ASFs of three softwoods examined indicate that discoloration in the accelerated lightfastness test is 250 times more severe than that in the indoor exposure test.

Mortar capping trials carried out at Corfe Castle by the National Trust have been monitored closely over the past seven years. These have appraised a range of hydraulic and high-calcium limes. The objectives of the trials have been to explore and promote the materials commonly described in historical literature and used in traditional building practice. A parallel programme of laboratory characterization of the physical properties of similar mixes has been carried out by BRE Limited.The trials were applied to a very high standard of design and workmanship in a context of harsh weather exposure. Good durability is evidenced by the hydraulic limes, mixes of hydraulic and high-calcium limes, and high-calcium lime with sufficient reactive set-additive or pozzolans. High-calcium lime mortars and those with less reactive set-additives showed early failure. These substantiate the claim in most historical literature that the durability of different lime mortars is variable, and it is necessary to specify ...

ESR is used to quantify the steady-state concentration of HALS-based nitroxyl radicals and the concentration of nitroxyl radicals produced when HALS and its inhibition cycle products are oxidized with peracid for four clearcoat/basecoat paint systems differing in HALS type, HALS concentration, clearcoat chemistry, and outdoor exposure conditions. Clearcoat bulk and surface analysis results are compared. Step-wise analysis is used to determine the distribution of HALS and its inhibition cycle products in two paint systems as a function of exposure. Micro-UV spectroscopy is used to determine the distribution of ultraviolet light absorber additive in the same paint systems. Taken together, the results indicate that the concentration behavior of HALS and UVA additives during the early stages of weather exposure can provide direct insight into the long-term weathering performance of clearcoat/basecoat paint systems.

Severely weathered window units were used to test various restoration methods and pretreatments. Sanded and unsanded units were pretreated with a consolidant or water repellent preservative, finished with an oil- or latex-based paint system, and exposed outdoors near Madison, WI, for five years. Pretreatments were applied to both window sashes (stiles and rails) and sills. In most cases, pretreatment with consolidants was detrimental to the finish. These pretreatments generally caused more flaking and cracking of the paint compared with that of untreated controls or penetrating water-repellent preservatives. The best results were obtained by a combination of sanding and pretreatment with a water-repellent preservative containing copper naphthenate or with tung oil.

L.), Fichte (Picea abies L.), Eichen-Kernholz (Quercus robur L.) und Douglasien-Kernholz (Pseudotsuga menziesii Franco) wurde zwei Jahre im Freiland ohne Erdkontakt bewittert. Die Melaminharzvergutung verzogerte bereits in geringer Konzentration den photochemischen Holzabbau und eine Besiedelung durch holzverfarbende Pilze betrachtlich, bewirkte jedoch keinen Schutz vor Risbildung und keinen Feuchteschutz. Im zweiten Jahr der Bewitterung uberschritten die Proben 25% Holzfeuchte an 9 Tagen (unbehandelte Douglasie), 21 Tagen (unbehandelte Eiche), 88 Tagen (unbehandelte Fichte), 129 bis 160 Tagen (MMF-Harz impragnierte Kiefer), 166 Tagen (unbehandelte Kiefer) und 236 Tagen (Kiefer mit Wetterschutzlasur). Bei Proben mit biozidfreier, transparenter Wetterschutzlasur stellte sich nach zweijahriger Bewitterung innerhalb von einer Stunde Wasserlagerung eine Holzfeuchte von 130% ein. Die lichtmikroskopische Untersuchung offenbarte im Inneren der lasierten Proben eine ausgedehnte Bakterienbesiedelung, welche fur die erhohte Wasseraufnahme und innere Wegsamkeit verantwortlich gemacht wird. Die an zahlreichen Stellen durch Anstrichblaue perforierte, jedoch diffusionsbremsende Lasur schuf durch lange Perioden hoher Holzfeuchte Lebensbedingungen fur Bakterien und Moderfaule.

Microbial activity in external wooden panels was estimated using the followingindicators: visual assessment of blue stain attack, isolation of fungi on a selective medium, FDAhydrolytic activity measurements and determination of the amount of ergosterol. Results showedthat a wall exposed to the south with somewhat higher risk for exposure to driving rain and with ahigher UV-light exposure was colonised by fungi to a much higher extent. The ventilated spacebehind the boarding was often attacked by blue-stain fungi which might indicate that theventilation rate had been insufficient. After 8 years external exposure under the prevailing climaticconditions the attack by micro-organisms on parts of the board far from end grain, or with endgrain protected with a metal flashing, was very low and seem to be independent on whether a purewater borne system, a mixed water-borne–solvent-borne system or a pure solvent-borne systemwas used for coating.

This paper presents data on performance of pigments in latex exterior house paints derived from kaolin. The paints were prepared containing several such pigments and were exposed to the weather at four locations for two to six years.

Eight urea-formaldehyde (UF) glues and one acid phenolic (PF) glue were compared with “established” glues of the casein and resorcinol (RF) types as for long-term durability, by use of accelerated and natural ageing. The purpose was to evaluate these glues for structural softwood bonding. After unprotected outdoor exposure, only the phenolresorcinols (PRF) still meet the delamination requirements of the Norwegian Glulam Control (Norsk Treteknisk Institutt, 1975) after 10 years. In the case of indoor (30 years) and protected outdoor exposure (22 years), all glues except acid PF still have sufficient dry strength left when judged by Norwegian Standard 3470 (NSF 1979). The wet strength after 30 years (not tested for caseins) is still satisfactory for the RF/PRF adhesives and for the modified UFs, but not for the straight UFs and the acid PF. The accelerated ageing distinguished between glue types in the same order as natural ageing. Conclusions: The caseins and the modified UFs are considered suitable for indoor and protected outdoor exposure. The RF and PRF adhesives are considered suitable for indoor as well as outdoor exposure. The acid PF is considered unsuitable, and the straight UFs with inert fillers should be regarded with suspicion due to their steadily decreasing wet strength. This experiment was supported by The Royal Norweigian Council for Scientific and Industrial Research, and by Casco Nobel AB and Dyno Industrier A/S.

Along with the improvement in weathering resistance of architectural coatings, staining has become a focus of interest among people working on urban buildings. Basic studies of staining have been carried out by the Public Works Research Institute Ministry of Construction to develop coatings which are largely free of objectionable stains in the form of mottles and streaks. Through this study, it has been shown that there is a correlation between the degree of staining of a surface when evaluated visually and ΔL∗, used as a numerical scale, lightness difference. The staining is noticeable for everybody when ΔL∗ exceeds −10. The staining substances can be classified into two types, urban type and rural type. It was found that the urban type usually contains more lipophilic substances and is more lipophilic than the rural type. Taking into account the finding that the urban type staining is more intensive than the rural type, a group of urban type staining preventive coatings has been designed, which makes it easier for rain to rinse off the lipophilic stain. A technology has been developed which keep the surface of the coatings hydrophilic for an extended period of time without detracting from the weathering resistance. The staining preventive coating has been examined by newly developed accelerated tests. Its excellent staining preventive performance and weathering resistance have been proved. Subsequent field applications on condominiums and road constructions also demonstrate the excellent results.

In March of 1993, components of a CVN Battle Group deploying to the Mediterranean encountered heavy seas in the area between Norfolk and Bermuda. This was the storm referred to in the press as The Blizzard of '93. The ships involved reported damage as a result of wave action, but continued their transit without incident and with full mission capability intact. In order to investigate the damage, it was necessary to determine what the encountered wave conditions were. Because the probable time of damage was at night, with no visual observations available, as well as because of the large variations in reported conditions, it was decided that other methods would be investigated to determine the actual conditions encountered. Four data sources were used in an attempt to determine the encountered wave conditions. This paper describes the data sources, the comparison of the data, and the conclusion that, while severe, the conditions are not likely to represent the lifetime maximum for design

Objectives To review Campylobacter cases in England and Wales over 2 decades and examine the main factors/mechanisms driving the changing epidemiology. Design A descriptive study of Campylobacter patients between 1989 and 2011. Cases over 3 years were linked anonymously to postcode, population density, deprivation indices and census data. Cases over 5 years were anonymously linked to local weather exposure estimates. Setting Patients were from general practice, hospital and environmental health investigations through primary diagnostic laboratories across England and Wales. Participants There were 1 109 406 cases. Outcome measures Description of changes in Campylobacter epidemiology over 23 years and how the main drivers may influence these. Results There was an increase in Campylobacter cases over the past 23 years, with the largest increase in people over 50 years. Changes in the underlying population have contributed to this, including the impacts of population increases after World War I, World War II and the ‘baby boom’ of the 1960s. A recent increase in risk or ascertainment within this population has caused an increase in cases in all age groups from 2004 to 2011. The seasonal increase in cases between weeks 18 (Early May) and 22 (Early June) was consistent across ages, years and regions and was most marked in children and in more rural regions. Campylobacter prevalence by week in each region correlated with temperature 2 weeks before. There were higher prevalences in areas with a low population density, low deprivation and lower percentage of people of ethnic origin. Data from sero–phage and multilocus sequence typing show a few common types and many uncommon types. Conclusions The drivers/mechanisms influencing seasonality, age distribution, population density, socioeconomic and long-term differences are diverse and their relative contributions remain to be established. Surveillance and typing provide insights into Campylobacter epidemiology and sources of infection, providing a sound basis for targeted interventions., Article summary Article focus Campylobacter is the most common bacterial cause of diarrhoea, affecting about half a million people annually. Chicken is thought to be the most common source of infection and the most common vehicle for transmission while environmental sources are suspected to play an important role the seasonality. A few types are common and many types are rare. Key messages Campylobacter is increasing in older people, particularly men, and population structure is partly driving this increase. Antibiotic resistance has increased over recent years. There are lower rates of reporting in more densely populated areas and more deprived areas. The distribution of types suggests that immunity may be important. Strengths and limitations of this study The study is large and captures patients from across the country, pulling together a good picture of the epidemiology of Campylobacter. The disease burden may be underestimated due to low reporting in deprived areas that may reflect poor access to healthcare or prior infection.

This paper reports on ongoing research in areas related to wind-driven rain and its interaction with buildings. Progress in wind tunnel modelling of wind-driven rain and the resulting observations of wetting patterns are reported. Preliminary results of investigations into mean and unsteady pressure gradients on buildings are also reported. An eventual objective of this work is to synthesize the results of these studies into future recommendations for compartmentalization of pressure-equalized rainscreens.

The relationship between the amount of wind-driven rain or driving-rain and the driving-rain index (product of annual rainfall and mean wind speed) is studied. An analytical approach is proposed to obtain the relationship between these two quantities. It is observed that they are related by two factors, (a) the driving-rain coefficient and (b) the co-occurrence factor. The driving-rain coefficient is shown in the paper to be a function of drop size distribution which depends on the rainfall intensity and the type of rain. The co-occurrence factor describes the amount of correlation between wind and rain. The characteristics of wind and rain at four meteorological stations across Sydney, Australia are studied. The driving-rain characteristics for these sites are observed to be different. The amount of driving-rain for a given site is also found to be very different compass directions. They can differ by a factor of 10 and more. It is believed that for the purpose of weather resistance design of building facade, the directional driving-rain index should be used. Using the proposed method, the co-occurrence factor for the dominant driving-rain direction in Sydney is found to be 1.12 and the driving rain coefficient is calculated to be 0.204. With these two factors the amount of driving rain can be calculated from the driving-rain index.