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Item does not contain fulltext, Nemaline myopathy (NM) is one of the most common non-dystrophic genetic muscle disorders. NM is often associated with mutations in the NEB gene. Even though the exact NEB-NM pathophysiological mechanisms remain unclear, histological analyses of patients' muscle biopsies often reveal unexplained accumulation of glycogen and abnormally shaped mitochondria. Hence, the aim of the present study was to define the exact molecular and cellular cascade of events that would lead to potential changes in muscle energetics in NEB-NM. For that, we applied a wide range of biophysical and cell biology assays on skeletal muscle fibres from NM patients as well as untargeted proteomics analyses on isolated myofibres from a muscle-specific nebulin-deficient mouse model. Unexpectedly, we found that the myosin stabilizing conformational state, known as super-relaxed state, was significantly impaired, inducing an increase in the energy (ATP) consumption of resting muscle fibres from NEB-NM patients when compared with controls or with other forms of genetic/rare, acquired NM. This destabilization of the myosin super-relaxed state had dynamic consequences as we observed a remodeling of the metabolic proteome in muscle fibres from nebulin-deficient mice. Altogether, our findings explain some of the hitherto obscure hallmarks of NM, including the appearance of abnormal energy proteins and suggest potential beneficial effects of drugs targeting myosin activity/conformations for NEB-NM.

Logistics of roundwood and biomass comprise a high number of operations, machinery, storage sites and transportable roundwood and biomass assortments. Moreover, complex and highly varying operational environment through the year poses logistics challenges incurring additional costs. An extensive review of studies was conducted in Sweden and Finland concerning roundwood and biomass logistics, starting from roadside landings and ending with delivery to a mill or a conversion facility. The main aim of the review was to describe trends in roundwood and biomass logistics since the start of the century. Papers were classified to categories of truck transports and roads, terminals, multimodal transports, storage and supply chain logistics. Slightly over 50% of reviewed articles were constrained to biomass only, 31% to roundwood only and 14% to both. Rapid technology development, amendments concerning road transports, increasing environmental concerns and forestry sector’s push to decrease the logistics costs can be seen as the biggest drivers for the reviewed studies and their study objectives. These aspects will also drive and increase the demand for research and development in roundwood and biomass logistics in the future.

One of the challenges in welding ultrahigh- and high-strength steels is the effect of limited heat input on the production times. As the cooling times of these steels have to be controlled tightly to achieve the desired weld qualities, such as impact toughness, the allowed heat input is low, which translates to reduced material deposition rates. This means that multipass welding is often required to achieve good weld quality. Because multipass welding is often used, the time spent waiting for the weld to cool to the desired interpass temperature, which is usually 100 °C, is often multiple minutes for each weld pass. The trend so far has been that more efficient welding processes have been developed to maximize the material deposition rates without increasing the heat input. Even with these efforts the use of multipass welding is still required. The use of ultrahigh- or high-strength steels reduces the material cost, allows for lighter and thinner structures while reducing transport costs as well. However, the production cost can negate some of these cost savings because of the wasted time due to the aforementioned problems with multipass welding. To establish the feasibility of introducing forced cooling to the welding process, the effect of the cooling on the mechanical properties was studied by conducting tensile, impact, and fatigue strength experiments with Gleeble simulated and with welded specimens. Also, the microstructural differences were studied. The tensile properties were improved when forced cooling was used to cool the weld down to the temperature of 100 °C and the impact toughness was also improved or remained unchanged. The cooling also demonstrated that it may have a positive effect on the fatigue strength of the steel. The grain size was usually reduced due to the forced cooling and larger quantities of lower bainite could be seen in some of the experiments. Overall there were no negative effects caused by the forced cooling on the steel., Tiivistelmä Hitsausprosesseissa yksi merkittävimmistä ongelmista erikoislujilla teräksillä on saavuttaa riittävän nopeat jäähdytysajat sillä hidas jäähtyminen heikentää hitsin lujuutta. Jäähdytysnopeuksien kasvattaminen vaatii lämmöntuonnin vähentämistä, jolloin hitsipalkojen lukumäärää joudutaan vastaavasti kasvattamaan. Hitsipalkon lämpötila pitää olla esim. 100°C ennen kuin seuraava palko voidaan hitsata päälle. Jäähtyminen saattaa kestää kuitenkin useita minuutteja, jolloin tuotannon tehokkuus kärsii palkojen lukumäärän lisääntyessä. Palkojen määrää on pyritty vähentämään kehittämällä tehokkaampia hitsausprosesseja, mutta siitä huolimatta monipalkohitsausta käytetään yleisesti. Hitsausprosessiin käytetty tehollinen työaika kasvaa jäähtymiseen kuluvan ajan vuoksi ja se kumoaa helposti muutoin optimoidut materiaali- ja kuljetuskustannukset. Tämän tutkimuksen tarkoituksena oli tutkia nopeutetun eli pakotetun jäähdytyksen vaikutusta erikoislujien terästen mekaanisiin ominaisuuksiin sekä selvittää pakotetun jäähdytyksen aikaansaamiseksi kehitetyn laitteiston suorityskykyä ja vaikutusta tuotannon tehokkuuteen. Tutkittujen terästen mekaaniset ominaisuudet määritettiin lujuus-, iskusitkeys- ja väsymislujuuskokein. Lisäksi jäähdytyksen vaikutusta teräksen faasirakenteeseen tutkittiin mikrorakennetarkastelujen kautta. Työssä osoitetaan, että pakotettu jäähdytys paransi hitsien lujuusominaisuuksia kuten myötö- ja murtolujuutta. Lisäksi iskusitkeys kasvoi osalle näytteistä, muiden pysyessä ennallaan. Väsytystestausta tehtiin vain osalle näytteistä mutta niilläkin vaikutus oli positiivinen eli väsymislujuus näytti kasvavan. Teräksen hitsialueen mikrorakenteeseen liittyen, jäähdytys pienensi HAZ-vyöhykkseen raekokoa osassa testeistä, sekä joidenkin terästen kohdalla ala-bainiitin osuus kasvoi selkeästi. Oleellista kokeellisessa osuudessa oli, että jäähdytyksellä ei ollut yhdenkään kokeen kohdalla heikentävää vaikutusta tutkittavan teräksen mekaanisiin ominaisuuksiin. Jäähdyty

In high- and ultrahigh-strength steel welding, interpass cooling time is an important factor affecting productivity and welding costs. Usually, welding heat input is restricted to meet the relatively short recommended cooling times between 800 and 500 °C (t8/5), which are prescribed by the need to meet weld strength and toughness properties. This, in turn, leads to the need for multipass welding with the interpass waiting times needed for the weld to cool to a sufficiently low interpass temperature. Welding productivity is affected by both the number of passes and the interpass waiting time. With a view to minimizing the total number of passes needed for a given preparation, it is beneficial for the interpass temperature to be as low as possible as this permits higher heat input for a given t8/5. On the other hand, low interpass temperature requires longer interpass waiting times. Therefore, this research concerns the potential of introducing copper heat sinks adjacent to the weld to reduce the time it takes for the weld to cool down to the interpass temperature. It is demonstrated that, in the case of a butt weld in a 6 mm thick base plate MAG welded with a weld energy of 1 kJ/mm and an interpass temperature of 100 °C, copper heat sinks almoust halve the interpass waiting time. This can have a marked effect on the overall productivity when welding highand ultrahigh-strength steels and increase their attractiveness for steel construction.

The effect of forced cooling using heat sinks on the mechanical properties and interpass waiting time of two-pass welds has been studied for a martensitic steel with a yield strength of 960 MPa when the interpass temperature was 100 °C. Cross-weld tensile and − 40 °C Charpy-V impact toughness properties were examined. The use of heat sinks is shown to result in a beneficial increase of the cross-weld yield strength but at the expense of the yield-to-tensile strength ratio. Due to its particularly detrimental effect on the heat-affected zone (HAZ) toughness of multipass welds, special attention was given in the Charpy-V toughness of the intercritically reheated coarse-grained HAZ (ICCGHAZ) by also testing simulated ICCGHAZs. It is shown that forced cooling has a beneficial effect in respect of the toughness of this simulated subzone and on the Charpy-V toughness of the HAZ of the actual welds. The interpass cooling time during the two-pass welding was reduced by 37%. The results indicate that, in the case of high-strength steels, it may be possible to simultaneously improve both welding productivity and mechanical properties by using forced cooling down to 100 °C to reduce waiting time between weld passes.

The effects of forced cooling, i.e., forced cooling rate and forced cooling finish temperature, on the tensile and impact toughness properties of simulated weld coarse-grained heat-affected zones has been explored in the case of a low-carbon thermomechanically processed steel with a yield strength of 700 MPa. The forced cooling finish temperatures that were studied were 400, 300, 200, and 100 °C and the forced cooling rates were 50 and 15 °C/s. Coarse-grained heat-affected zones were simulated using a Gleeble 3800 thermomechanical simulator. For the steel concerned, strength and impact toughness improved significantly when the steel was cooled rapidly to 200 or 100 °C. The results indicate that it may be possible to substantially improve welding productivity by using forced cooling to reduce interpass times.

The effects of forced cooling, meaning forced cooling rate and forced cooling finish temperature, on the tensile and impact toughness properties of simulated weld coarse-grained heat-affected zones have been studied for a commercial grade martensitic steel with a yield strength of 960 MPa. The simulations were done by using a Gleeble 3800 to give forced cooling finish temperatures of 500, 400, 300, 200, and 100 °C and forced cooling rates of 50 and 15 °C/s. For the steel studied, strength significantly increased with no significant negative effects on impact toughness when the steel was cooled rapidly to 200 or 100 °C at 15 °C/s. The results indicate that it may be possible to improve welding productivity and mechanical properties of the steel by using forced cooling down to 100 °C to reduce waiting time between weld passes.