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This article defines minimalist running shoes and examines physiological, biomechanical, and injury rate differences when running in conventional versus minimalist running shoes. A minimalist shoe is one that provides "minimal interference with the natural movement of the foot, because of its high flexibility, low heel to toe drop, weight and stack height, and the absence of motion control and stability devices." Most studies indicate that running in minimalist shoes results in a lower physiological energy cost than running in conventional shoes, likely because of the lower weight of the minimalist shoe. Most individuals running in conventional shoes impact the ground heel first (rearfoot strike pattern), whereas most people running in minimalist shoes tend to strike with the front of the foot (forefoot strike pattern). The rate at which force is developed on ground impact (i.e., the loading rate) is generally higher when running in conventional versus minimalist shoes. Findings from studies that have looked at associations between injuries and foot strike patterns or injuries and loading rates are conflicting, so it is not clear if these factors influence injury rates; more research is needed. Better-designed prospective studies indicate that bone stress injuries and the overall injury incidence are higher in minimalist shoes during the early weeks (10-12 weeks) of transition to this type of footwear. Longer-term studies are needed to define injury rates once runners are fully transitioned to minimalist shoes. At least one longer-term minimalist-shoe investigation is ongoing and, hopefully, will be published soon.

Airborne mineral dust is an important component of the Earth system and is increasingly predicted prognostically in weather and climate models. The recent development of data assimilation for remotely sensed aerosol optical depths (AODs) into models offers a new opportunity to better understand the characteristics and sources of model error. Here we examine assimilation increments from Moderate Resolution Imaging Spectroradiometer AODs over northern Africa in the Met Office global forecast model. The model underpredicts (overpredicts) dust in light (strong) winds, consistent with (submesoscale) mesoscale processes lifting dust in reality but being missed by the model. Dust is overpredicted in the Sahara and underpredicted in the Sahel. Using observations of lighting and rain, we show that haboobs (cold pool outflows from moist convection) are an important dust source in reality but are badly handled by the model's convection scheme. The approach shows promise to serve as a useful framework for future model development.

This is the second of a two-part series addressing symptoms, evaluation, and treatment of load carriage- related paresthesias. Part 1 addressed rucksack palsy and digitalgia paresthetica; here, meralgia paresthetica (MP) is discussed. MP is a mononeuropathy involving the lateral femoral cutaneous nerve (LFCN). MP has been reported in load carriage situations where the LFCN was compressed by rucksack hipbelts, pistol belts, parachute harnesses, and body armor. In the US military, the rate of MP is 6.2 cases/10,000 personyears. Military Servicewomen have higher rates than Servicemen, and rates increase with age, longer loadcarriage distance or duration, and higher body mass index. Patients typically present with pain, itching, and paresthesia on the anterolateral aspect of the thigh. There are no motor impairments or muscle weakness, because the LFCN is entirely sensory. Symptoms may be present on standing and/or walking, and may be relieved by adopting other postures. Clinical tests to evaluate MP include the pelvic compression test, the femoral nerve neurodynamic test, and nerve blocks using lidocaine or procaine. In cases where these clinical tests do not confirm the diagnosis, specialized tests might be considered, including somatosensory evoked potentials, sensory nerve conduction studies, high-resolution ultrasound, and magnetic resonance imaging. Treatment should initially be conservative. Options include identifying and removing the compression if it is external, nonsteroidal inflammatory medication, manual therapy, and/or topical treatment with capsaicin cream. Treatments for intractable cases include injection of corticosteroids or local anesthetics, pulsed radiofrequency, electroacupuncture, and surgery. Military medical care providers may see cases of MP, especially if they are involved with units that perform regular operations involving load carriage.

2 fig., bibliogr. p. 20-23.

European cold-formed hollow sections in general exhibit better toughness properties than required by EN 10219. However, limits in applying the toughness related rules for the choice of steel material in EN 1993 1 10 to cold-formed hollow sections still constitute barriers to free marketing. By requests from European producers a conservative assessment procedure has been developed which is based on toughness measurements and a concept using effective strains. Due to the cold-forming process such plastic strains may occur in the bent areas of the profiles associated with a noticeable reduction in material toughness. For the degradation of these toughness properties an appropriate temperature shift Delta Tcf has been derived for both circular and rectangular hollow sections. In order to guarantee the proper application of this temperature shift Table 2.1 in EN 1993 1 10 had to be extended to lower temperatures down to -120 °C., JRC.G.5-European laboratory for structural assessment

This JRC-Scientific and Technical Report gives information from pre-normative research for methods to prevent liquid metal assisted cracking of prefabricated structural components during zinc-coating in the liquid zinc melt, that may impair the structural safety of structures in which the components are built in. This information provides a platform upon which further European design and product specifications can be developed. It may in particular affect the further developments of EN 1993, EN 1090, EN ISO 1461 and EN ISO 14713. This report gives the state-of-the-art in understanding the mechanism of liquid metal assisted cracking in the zinc bath and methods and models that may be used to avoid it. It could be a basis to propose rules for the design of steel components intended to be hot-dip-zinc-coated in such a way that the design is consistent with execution rules for hot-dip-zinc-coating. The workability of the rules proposed for all metal works and steel works that are fabricated under EN 1090 and galvanized according to the rules in this report is demonstrated by worked examples., JRC.DG.G.5-European laboratory for structural assessment

Analysis of fan sediments and post-incisive soils was combined with luminescence dating to re-assess Nemec and Postma's [Nemec, W., Postma, G., 1993. Quaternary alluvial fans in southwestern Crete: sedimentation processes and geomorphic evolution. In: Marzo, M., Puigdefábregas, C. (Eds.), Alluvial Sedimentation. Special Publication of the International Association of Sedimentologists, vol. 17, pp. 235-276] model of fan evolution on the Sfakian piedmont, southern Crete. Field mapping supports the assertion that sedimentation occurred in three developmental stages. Stage 1 sediments comprise angular debris flows forming small cone-like deposits; stage 2 fluvial gravels form large, relatively steep streamflow-dominated telescopic fans; and stage 3 sediments consist of coarse sieve-type alluvium, localised mudflows and hyperconcentrated flow deposits. Irrespective of gradient, fan surfaces are capped by post-incisive soils that form a chronosequence comprising remnant chromic luvisols. The most developed profiles, highest redness rating, and greatest concentrations of Fed and magnetic minerals are associated with soils formed on stage 1 surfaces. The stage 2 and 3 soils record progressively lower redness rating, Fed, and magnetic values, indicating that the stage 1 soils and fan surfaces formed first, followed by stage 2 and 3 soils and fan surfaces. Nanofossil data strongly suggest that stage 1 sedimentation commenced no earlier than the Early Pleistocene. Optically stimulated luminescence (OSL) results suggest that sedimentation responsible for stage 2 surfaces occurred between Marine Isotope Stage (MIS) 6 and MIS 2, while archaeological data indicate that stage 3 sedimentation is of Holocene age. The re-investigation of fan sediments and morphology corroborates the sedimentary and morphological elements of Nemec and Postma's model. The soil data support the model's assumptions that sedimentation was broadly synchronous across the piedmont and the locus of deposition progressively shifted away from the range-front zone. OSL dating suggests that previous age estimates assigned to fan stages 1 and 2 are too old. Climate appears to exert a fundamental control over fan development, with sedimentation occurring during cold stages and cold stage-interglacial transitions. Tectonic activity provides the relief required for fan development and controls fan incision. Local uplift resulted in variable rates of incision that culminated in differential fan segmentation across the piedmont. © 2007 Elsevier B.V. All rights reserved.

ill., bibliogr. (dissém.).