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The increasing demand for biofuels from logging residues require serious attention on the importance of dead wood substrates on clear-cuts for the many forestry-intolerant saproxylic (wood-inhabiting) species. In particular, the emerging harvest of low stumps motivates further study of these substrates. On ten clear-cuts we compared the species richness, abundance and species composition of saproxylic beetles hatching from four to nine year old low stumps, high stumps and logs of Norway spruce. By using emergence traps we collected a total of 2,670 saproxylic beetles among 195 species during the summers of 2006, 2007 and 2009. We found that the species assemblages differed significantly between high stumps and logs all three years. The species assemblages of low stumps, on the other hand, were intermediate to those found in logs and high stumps. There were also significant difference in species richness between the three examined years, and we found significant effect of substrate type on richness of predators and fungivores. As shown in previous studies of low stumps on clear-cuts they can sustain large numbers of different saproxylic beetles, including red-listed species. Our study does, in addition to this fact, highlight a possible problem in creating just one type of substrate as a tool for conservation in forestry. Species assemblages in high stumps did not differ significantly from those found in low stumps. Instead logs, which constitute a scarcer substrate type on clear-cuts, provided habitat for a more distinct assemblage of saproxylic species than high stumps. It can therefore be questioned whether high stumps are an optimal tool for nature conservation in clear-cutting forestry. Our results also indicate that low stumps constitute an equally important substrate as high stumps and logs, and we therefore suggest that stump harvesting is done after carefully evaluating measures to provide habitat for saproxylic organisms.

Loss of natural forests by forest clearcutting has been identified as a critical conservation challenge worldwide. This study addressed forest fragmentation and loss in the context of the establishment of a functional green infrastructure as a spatiotemporally connected landscape-scale network of habitats enhancing biodiversity, favorable conservation status, and ecosystem services. Through retrospective analysis of satellite images, we assessed a 50- to 60-year spatiotemporal clearcutting impact trajectory on natural and near-natural boreal forests across a sizable and representative region from the Gulf of Bothnia to the Scandinavian Mountain Range in northern Fennoscandia. This period broadly covers the whole forest clearcutting period; thus, our approach and results can be applied to comprehensive impact assessment of industrial forest management. The entire study region covers close to 46,000 km² of forest-dominated landscape in a late phase of transition from a natural or near-natural to a land-use modified state. We found a substantial loss of intact forest, in particular of large, contiguous areas, a spatial polarization of remaining forest on regional scale where the inland has been more severely affected than the mountain and coastal zones, and a pronounced impact on interior forest core areas. Salient results were a decrease in area of the largest intact forest patch from 225,853 to 68,714 ha in the mountain zone and from 257,715 to 38,668 ha in the foothills zone, a decrease from 75% to 38% intact forest in the inland zones, a decrease in largest patch core area (assessed by considering 100-m patch edge disturbance) from 6114 to 351 ha in the coastal zone, and a geographic imbalance in protected forest with an evident predominance in the mountain zone. These results demonstrate profound disturbance of configuration of the natural forest landscape and disrupted connectivity, which challenges the establishment of functional green infrastructure. Our approach supports the identification of forests for expanded protection and conservation-oriented forest landscape restoration. La pérdida de bosques naturales por causa de la tala uniforme de árboles en los mismos ha sido identificada como unreto muyimportantepara la conservación global. Esteestudioabordó la fragmentación y pérdida de bosques en el contexto del establecimiento de una infraestructura verde funcional como una red de hábitats a escala de paisaje conectados espacio-temporalmente que mejoren la biodiversidad, los estados favorables de conservación y los servicios ambientales. Por medio de un análisis retrospectivo de imágenes satelitales evaluamos una trayectoria de impacto espacio-temporal de 50 a 60 años de tala uniforme sobre bosques boreales naturales y casi naturales en una región considerable y representativa desde el Golfo de Botnia hasta la Cordillera Escandinava en el norte de Fenoescandia. Este rango cubre todo el periodo de tala uniforme en el bosque en términos generales; por lo tanto, nuestra metodología y resultados pueden aplicarse a la evaluación completa del impacto del manejo industrial de bosques. Toda la región de estudio cubría hasta 46,000 km² de paisaje dominado por bosque en una etapa tardía de la transición entre el estado natural o casi natural y el estado de uso de suelo modificado. Encontramos una pérdida sustancial de bosque intacto, particularmente para áreas grandes y contiguas, una polarización espacial del bosque restantea una escala regional en la que tierra adentro hay mayores afectaciones que en las zonas montañosas y costeras, y un impacto pronunciado sobre las áreas nucleares de los bosques interiores. Los resultados salientes fueron una disminución en el área del fragmento más grande de bosque intacto de 225, 853 a 68, 714 ha en la zona montañosa y de 257, 715 a 38, 668 ha en la zona de pie de monte, una disminución del 75% al 38% de bosque intacto en las zonas tierra adentro, una disminución en el área nuclear del fragmento más grande (valorada al considerar 100-m de perturbación al borde del fragmento) de 6, 114 a 351 ha en la zona costera, y un desbalance geográfico en los bosques protegidos con una evidente mayoría en la zona montañosa. Estos resultados demuestran una perturbación profunda de la configuración del paisaje de bosque natural y una conectividad interrumpida, lo que presenta un reto para el establecimiento de una infraestructura verde funcional. Nuestro enfoque sustenta la identificación de bosques para su protección expandida y la restauración del paisaje de bosque orientada hacia la conservación. 森林皆伐造成的自然森林丧失被认为是全世界面胳的重要保护挑战。功能性绿色基础设施是提高生物多 样性、保护状况和生态系统服务的时空上连接的景观尺度生境网络 本研究关注其建设中的森林破碎化和森林 丧失同题。通过分析卫星图像, 我们评估7\"芬诺斯坎通亚 (Fennoscancdia) 北部波的尼亚湾 (Gulf of Bothnia) 到 斯堪的纳维亚山脉(Scandinavian Mountain Range)大面积有代表性的自然和接近自然的北方森林受到 50-60 年森林皆伐的影响轨迹。这一时间段大致包括了整个森林皆伐期，因此我们的方法和结果可以应用于工业森林 管理的综合影响评估。整个研究区域覆盖了近紙000平方公里以森林为主的景風处于自然或接近自然的景 观向人为改造的土地利用类型过渡的后期。我们发现原始森林严重丧失，特别是大面积的连续区域，_ 余的森林 在区域尺度上发生空间的两极分化，其中内陆比山区和沿海地区受到更为严重的影响，内部森林核心区也受到明 显影响。突出的结果包括:山区最大的原始森林斑块面积从225,853公顷减少到 68,714 公埂而在山麓地区 从 257,715 公現滅少到38,668 公埂, 内陆地区从 75% 减少到 38%, 最大的斑块核心区域面积减少(根据 6,114 公顷到 351 公顷的沿海地区 100 米斑块边缘干扰的评估结果X 以及受保护森林的地理分布不平衡(主要在山 区) 。这些结果表明，自然森林景观配置受到严重干抵连接度受到破坏，这对建设功能性绿色基础设施提出了 挑战。我们的方法有助于确定扩大保护及进行保护导向的森林景观恢复的森林范围。

Gaseous emissions of modern Euro 6d vehicles, when tested within real driving emissions (RDE) boundaries, are, in most cases, at low levels. There are concerns, though, about their emission performance when tested at or above the boundaries of ambient and driving conditions requirements of RDE regulations. In this study, a Euro 6d-Temp gasoline direct injection (GDI) vehicle with three-way catalyst and gasoline particulate filter was tested on the road and in a laboratory at temperatures ranging between −30 °C and 50 °C, with cycles simulating urban congested traffic, uphill driving while towing a trailer at 85% of the vehicle’s maximum payload, and dynamic driving. The vehicle respected the Euro 6 emission limits, even though they were not applicable to the specific cycles, which were outside of the RDE environmental and trip boundary conditions. Most of the emissions were produced during cold starts and at low ambient temperatures. Heavy traffic, dynamic driving, and high payload were found to increase emissions depending on the pollutant. Even though this car was one of the lowest emitting cars found in the literature, the proposed future Euro 7 limits will require a further decrease in cold start emissions in order to ensure low emission levels under most ambient and driving conditions, particularly in urban environments. Nevertheless, motorway emissions will also have to be controlled well.

Residual stress measurements directly in the coated cutting edge are not possible with X-ray diffraction (XRD) due to the diameter of the X-ray beam. On the other hand, Raman microscopy enables measurements on the micrometer scale. Parameter variations in the PVD process were used to provide different residual stress states in (Al,Ti)N coatings on carbide cutting tools. They were examined by XRD in regions that can be reliably measured. The same area was then examined by Raman microscopy to determine the relationship of Raman peaks to the residual stress. Local high-resolution Raman measurements were then taken at the cutting edge and further influences on the Raman peak position besides residual stresses were excluded. In order to analyze the relationship between Raman peak shift and residual stress state, measurements were performed during a bending load. Finally, an outlook on further investigations is given.

The residual stress state in tool coatings can positively influence tool life. Measurement in strongly curved surfaces e.g. in the cutting edge area is only possible to a limited extent by means of X-ray diffraction (XRD). Raman spectroscopy offers great potential for determining the residual stress state in this area. Therefore, the aim is to determine the fundamental limits of residual stress measurement by XRD on coated carbide tools and to determine and evaluate the suitability of Raman spectroscopy. On typical cutting tools only a small area on the rake face can provide reliable measurement results using conventional XRD methods. Using the XRD results as reference, Raman spectroscopy shows plausible results for residual stresses induced into the coating by mechanical or thermal post-treatment. Coating-induced residual stresses cannot be reliably detected because other coating properties are also changed by modified coating processes that induce higher compressive residual stresses.

Brake wear particles are generated through frictional contact between the brake disc or brake drum and the brake pads. Some of these particles may be released into the atmosphere, contributing to airborne fine particulate matter (PM2.5). In this study, an onboard system was developed and tested to measure brake wear particles emitted under real-world driving conditions. Brake wear particles were extracted from a fixed volume enclosure surrounding the pad and disc installed on the front wheel of a light-duty vehicle. Real-time data on size distribution, number concentration, PM2.5 mass, and the contribution of semi-volatiles were obtained via a suite of instruments sub-sampling from the constant volume sampler (CVS) dilution tunnel. Repeat measurements of brake particles were obtained from a 42 min bespoke drive cycle on a chassis dynamometer, from on-road tests in an urban area, and from braking events on a test track. The results showed that particle emissions coincided with braking events, with mass emissions around 1 mg/km/brake during on-road driving. Particle number emissions of low volatility particles were between 2 and 5 × 109 particles/km/brake. The highest emissions were observed under more aggressive braking. The project successfully developed a proof-of-principle measurement system for brake wear emissions from transient vehicle operation. The system shows good repeatability for stable particle metrics, such as non-volatile particle number (PN) from the solid particle counting system (SPCS), and allows for progression to a second phase of work where emissions differences between commercially available brake system components will be assessed.

Background. Foraging efficiency is critical in determining the success of organisms and may be affected by a range of factors, including resource distance and quality. For social insects such as ants, outcomes must be considered at the level of both the individual and the colony. It is important to understand whether anthropogenic disturbances, such as forestry, affect foraging loads, independent of effects on the quality and distribution of resources. We asked if ants harvest greater loads from more distant and higher quality resources, how individual efforts scale to the colony level, and whether worker loads are affected by stand age. Methods. First, we performed a fine-scale study examining the effect of distance and resource quality (tree diameter and species) on harvesting of honeydew by red wood ants, Formica aquilonia , in terms of crop load per worker ant and numbers of workers walking up and down each tree (ant activity) (study 1). Second, we modelled what the combination of load and worker number responses meant for colony-level foraging loads. Third, at a larger scale, we asked whether the relationship between worker load and resource quality and distance depended on stand age (study 2). Results. Study 1 revealed that seventy percent of ants descending trees carried honeydew, and the percentage of workers that were honeydew harvesters was not related to tree species or diameter, but increased weakly with distance. Distance positively affected load mass in both studies 1 and 2, while diameter had weak negative effects on load. Relationships between load and distance and diameter did not differ among stands of different ages. Our model showed that colony-level loads declined much more rapidly with distance for small diameter than large diameter trees. Discussion. We suggest that a negative relationship between diameter and honeydew load detected in study 1 might be a result of crowding on large diameter trees close to nests, while the increase in honeydew load with distance may result from resource depletion close to nests. At the colony level, our model suggests that very little honeydew was harvested from more distant trees if they were small, but that more distant larger trees continued to contribute substantially to colony harvest. Although forestry alters the activity and foraging success of red wood ants, study 2 showed that it does not alter the fundamental rules determining the allocation of foraging effort.

We use a modified cathodic arc deposition technique, including an electromagnetic coil that introduces a magnetic field in the vicinity of the source, to study its influence on the growth of (Ti0.36Al0.64)N coatings. By increasing the strength of the magnetic field produced by the coil, the cathode arc spots are steered toward the edge of the cathode, and the electrons are guided to an annular anode surrounding the cathode. As a result, the plasma density between the cathode and substrate decreased, which was observed as a lateral spread of the plasma plume, and a reduction of the deposition rate. Optical emission spectroscopy shows reduced intensities of all recorded plasma species when the magnetic field is increased due to a lower number of collisions resulting in excitation. We note a charge-to-mass ratio decrease of 12% when the magnetic field is increased, which is likely caused by a reduced degree of gas phase ionization, mainly through a decrease in N2 ionization. (Ti0.36Al0.64)N coatings grown at different plasma densities show considerable variations in grain size and phase composition. Two growth modes were identified, resulting in coatings with (i) a fine-grained glassy cubic and wurtzite phase mixture when deposited with a weak magnetic field, and (ii) a coarse-grained columnar cubic phase with a strong magnetic field. The latter conditions result in lower energy flux to the coating’s growth front, which suppresses surface diffusion and favors the formation of c-(Ti,Al)N solid solutions over phase segregated c-TiN and w-AlN.

This paper describes the results of a series of tests on a heavy-duty truck diesel engine using conventional and low viscosity lubricants. The objectives were to explore the impact of reducing lubricant viscosity on wear, friction and fuel consumption. The radiotracing Thin Layer Activation method was used to make on-line measurements of wear at the cylinder liner, top piston ring, connecting rod small end bush and intake cam lobe. The engine was operated under a wide range of conditions (load, speed and temperature) and with lubricants of several different viscosity grades. Results indicate the relationship between lubricant viscosity and wear at four critical locations. Wear at other locations was assessed by analysis of wear metals and post test inspection. The fuel consumption was then measured on the same engine with the same lubricants. Results indicate the relationship between oil viscosity and fuel consumption under a wide range of operating conditions. Expected fuel consumption improvements over a typical drive cycle were calculated. Friction of the whole engine was calculated from measurements of cylinder pressure and brake torque, with two of the low viscosity oils and, in addition, a five stage motored friction teardown test was performed. Together these results were used to explore the relationship between lubricant viscosity and friction across a range of operating conditions.