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Shoe microclimate (temperature and humidity) has been suggested to contribute to perceptions of foot thermal comfort. However, limited data is available for perceptual responses in relation to shoe microclimate development both over time and within different areas of the shoe. This study evaluates perceptions of foot thermal comfort for two running shoes different in terms of air permeability in relation to temporal and spatial characteristics of shoe microclimate. The temporal characteristics of shoe microclimate development were similar for both shoes assessed. However, higher temperatures and humidity were observed for the less permeable shoe. Changes to shoe microclimate over time and differences between shoes were perceivable by the users.This study provides the most detailed assessment of shoe microclimate in relation to foot thermal comfort to date, providing relevant information for footwear design and evaluation. physical activity where the feet are enclosed in shoes for extended periods of times i.e. marathon runners (Auger et al. 1993). Intermediate levels of moisture have also been shown to increase coefficients of friction which have been found to influence the probability of blister formation (Sulzberger et al. 1966). Changes to the shoe microclimate therefore encourage the growth of microorganisms which can lead to odour development and to poor foot health. Knowledge regarding the subjective evaluation of shoe microclimate is limited, with little published information available. Although subjective perception of foot may not always coincide with measured foot (Barkley et al. 2011), local discomfort has been attributed to elevations in temperature rather than elevations in the moisture content both within hiking boots (Arezes et al. 2013) and within sock and boot liner materials worn within protective footwear (Irzmanska et al. 2013). The influence moisture has on foot comfort therefore requires further investigation as it is unknown whether changes in temperature and/or humidity help an individual in determining perceptions of thermal comfort. Despite the impact shoe microclimate has on foot health and foot thermal comfort, to our knowledge no quantitative shoe microclimate data is available over time, within different areas of the shoe or in relation to perceptual responses specifically for sports related footwear. With exercise, metabolic heat generation and sweat rates are high and so balancing the amount of heat supplied to or generated by the feet with heat loss becomes crucial. Currently, only changes to foot during running have been reported (Barkley et al. 2011; Shimazaki and Murata 2015; Shimazaki et al. 2015). During a 30 minute running bout at 12 km hr -1 temperature elevations from rest of 8.2°C were observed at the heel and 4.8°C at the neck of the big toe, foot regions associated with high contact loads and pressure during running (Shimazaki and Murata 2015). Increased ventilation within running shoes has also been shown to produce a cooling effect, reducing foot elevations, particula...

This paper reports on precision measurements of conversion lines in the decay of 83mKr with nuclear transition energies of 32.1 keV and 9.4 keV, respectively. The spectra were taken from a submonolayer surface of 83mKr frozen onto a cold backing, using the new Mainz solenoid retarding spectrometer. The high luminosity and resolution of this instrume~t enables the observation of all allowed conversion lines up to the N-shell and to fully separate the elastic component from inelastic satellites. The combined analysis of the data yields the transition energies E, = 321 51.5 + 1.1 eV and 9405.9 + 0.8 eV, respectively.' The experiment served also to pilot the application of this spectrometer to the question of a finite neutrino rest mass, searched for in the P-decay spectrum of tritium and to problems in precision electron spectroscopy in general. primarily designed to investigate the P-spectrum of frozen molecular tritium near its endpoint in search for a finite neutrino rest mass. For that purpose it is equipped with a source substrate cooled down to 4.2 K onto which a thin film of a gaseous source material -in that case T, PACS-is frozen. The design of the apparatus thus attempts to optimize simultaneously the luminosity and the resolution as well as to minimize the deterioration of the spectrum by energy losses in the source. These features qualify the instrument not only for the tritium case but also for other problems in precision electron spectroscopy, in particular concerning surface studies.As the first experiment performed with this new instrument, we report in t h s paper on a measurement of conversion lines in the decay of 83mKr. Its isomeric state (I= 112, TI,= 1.86 h) is fed by the mother isotope 83Rb ( T l 2 = 83 d) with a branching ratio of 77,9%. The two subsequent transitions are highly converted yielding electron lines with energies ranging from' about 7 keV to 32 keV [2]. In the following sections we describe the experimental procedure and results. We also give a detailed analysis of the data concerning the position and lineshape of the elastic components, position and strength of shake up/shake off satellites, shifts due to surface effects, and nuclear transition energies. Experimental setup and procedure The solenoid retarding spectrometer (SRS)The design and function of the SRS are sketched in Fig. 1. Source and detector are placed in the bores of superconducting solenoids (S1 and S3) which, in combmation with a third solenoid (S2) in between S 1 and S3, provide the magnetic guiding field. S 1 and S 2 are set to the same field of about B, = 2.4 T, whereas S 3 1s set at a variable, but lower field (~0 . 6 T) in order to optimize the size of the image of the source and to lim~t the maxlrnum angle of incidence of the electrons onto the detector. A symmetric set of ring electrodes produces a retarding and

The endpoint region of the P-spectrum of tritium was remeasured by an electrostatic spectrometer with magnetic guiding field. It enabled the search for a rest mass of the electron-antineutrino with improved precision. The result is in: = -39 f 34,t,t f lSsysf ( e~/ c~)~, from which an upper limit of m, < 7.2 ev/c2 may be derived. The experiment yields the 'atomic mass difference m (T) -rn ( 3~e ) =-18 591 f 3 ev/c2.The cjuestion of a no*-vanishing neutrino rest mass is of fundamental importance in .particle and astrophysics. It therefore caused considerable excitement when Lubimov and collaborators [1',2] published a finite value for the electron-antineutrino rest mass m, obtained from a measurement of the endpoint region of the P-decay of tritium with a new, dedicated spectrometer of high resolution and luminosity [ 3 ] . It took a number of years until this result was checked with equivalent instrume~lts by groups in Ziirich [4] and Los Alamos [5] and disproved due to essential improvements of source and data analysis [6,7]. At present, it seems that this generation of experiments is capable of reaching a precision of am: = 100 (ev/c2 l 2 (see table 3 ) .A radically different type of P-spectrometer was proposed independently at several places [8,9]. It acts as an electrostatic filter guiding the electrons adiabatically along the,.lines of an inhomogeneous magnetic field. If the source is placed in a strong magnetic field Bo a n d the retarding potential Uo reaches its maximum in a much weaker magnetic field B1, the full forward solid angle of electfons emitted with energy E is analyzed with a filter width of AE = (BI /Bo) E. This is due to the adiabatic transformation of transverse cyclotron energy E l around the B-lines into longitudinal energy Ell along the B-lines by the magnetic field gradient reducing E l (which cannot, be analyzed electrostatically) in proportion to the magnetic field. Based on this principle,~two somewhat different spectrometers have been set up in recent years at INR in Troitzk [ 101 and at Mainz University. For details of the design, function and performance of the Mainz solenoid retarding spectrometer (SRS) and for further references see refs. [ l l, 121.The experiment described here was performed under the follo-wing conditions. The source is placed at a field Bs = 0.96B0,' slightly in front of the field maximum of the source solenoid which is set to Bo = 2.4 T, limiting the accepted polar angles to 19 < 78". The magnetic field reaches its minimum BI = 8 x T in the symmetry plane of the spectrometer, where Uo maximizes. Retardation of the electrons and reacceleration after the filter is provided by two sets of electrodes arranged symmetrically around the central one. Under these conditions the rise of the transmission from 0 to 1 within the interval E (1 -BI / B o ) G eUd d E is given by [12] Elsevier Science Publishers B.V.