Fries, Lotze, and von Kries

Remarks on the emergence of the concept “Spielraum” as a foundation for probability theory

First metatarsophalangeal joint range of motion is associated with lower limb kinematics in individuals with first metatarsophalangeal joint osteoarthritis.

BACKGROUND: Osteoarthritis of the first metatarsophalangeal joint (1st MTP joint OA) is a common and disabling condition that results in pain and limited joint range of motion. There is inconsistent evidence regarding the relationship between clinical measurement of 1st MTP joint maximum dorsiflexion and dynamic function of the joint during level walking. Therefore, the aim of this study was to examine the association between passive non-weightbearing (NWB) 1st MTP joint maximum dorsiflexion and sagittal plane kinematics in individuals with radiographically confirmed 1st MTP joint OA. METHODS: Forty-eight individuals with radiographically confirmed 1st MTP joint OA (24 males and 24 females; mean age 57.8 years, standard deviation 10.5) underwent clinical measurement of passive NWB 1st MTP joint maximum dorsiflexion and gait analysis during level walking using a 10-camera infrared Vicon motion analysis system. Sagittal plane kinematics of the 1st MTP, ankle, knee, and hip joints were calculated. Associations between passive NWB 1st MTP joint maximum dorsiflexion and kinematic variables were explored using Pearson's r correlation coefficients. RESULTS: Passive NWB 1st MTP joint maximum dorsiflexion was significantly associated with maximum 1st MTPJ dorsiflexion (r = 0.486, p < 0.001), ankle joint maximum plantarflexion (r = 0.383, p = 0.007), and ankle joint excursion (r = 0.399, p = 0.005) during gait. There were no significant associations between passive NWB 1st MTP joint maximum dorsiflexion and sagittal plane kinematics of the knee or hip joints. CONCLUSIONS: These findings suggest that clinical measurement of 1st MTP joint maximum dorsiflexion provides useful insights into the dynamic function of the foot and ankle during the propulsive phase of gait in this population

Generation of three-cycle multi-millijoule laser pulses at 318 W average power

The generation of three-cycle multi-millijoule pulses at 318W power is reported by compressing pulses of a Yb-fiber chirped pulse amplifier in a 6 m long stretched flexible hollow fiber. This technique brings high-power lasers to the few-cycle regime. (c) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreemen

From Euclidean Geometry to Knots and Nets

This document is the Accepted Manuscript of an article accepted for publication in Synthese. Under embargo until 19 September 2018. The final publication is available at Springer via https://doi.org/10.1007/s11229-017-1558-x.This paper assumes the success of arguments against the view that informal mathematical proofs secure rational conviction in virtue of their relations with corresponding formal derivations. This assumption entails a need for an alternative account of the logic of informal mathematical proofs. Following examination of case studies by Manders, De Toffoli and Giardino, Leitgeb, Feferman and others, this paper proposes a framework for analysing those informal proofs that appeal to the perception or modification of diagrams or to the inspection or imaginative manipulation of mental models of mathematical phenomena. Proofs relying on diagrams can be rigorous if (a) it is easy to draw a diagram that shares or otherwise indicates the structure of the mathematical object, (b) the information thus displayed is not metrical and (c) it is possible to put the inferences into systematic mathematical relation with other mathematical inferential practices. Proofs that appeal to mental models can be rigorous if the mental models can be externalised as diagrammatic practice that satisfies these three conditions.Peer reviewe

Special theme article : science and sociology of footwear

Journal editorial

Neuropathic pain associated with first metatarsophalangeal joint osteoarthritis: frequency and associated factors.

OBJECTIVE: To determine whether neuropathic pain is a feature of first metatarsophalangeal (MTP) joint osteoarthritis (OA). METHODS: Ninety-eight participants (mean age 57.4 years, standard deviation 10.3) with symptomatic radiographic first MTP joint OA completed the painDETECT questionnaire (PDQ), which incorporates nine questions regarding the intensity and quality of pain. The likelihood of neuropathic pain was determined using established cut-points of the PDQ. Participants with unlikely neuropathic pain were then compared to those with possible/likely neuropathic pain in relation to age, sex, general health (Short Form [SF] 12), psychological wellbeing (Depression, Anxiety and Stress Scale), pain characteristics (self-efficacy, duration, and severity), foot health (Foot Health Status Questionnaire [FHSQ]), first MTP dorsiflexion range of motion and radiographic severity. Effect sizes (Cohen's d) were also calculated. RESULTS: Thirty (31%) participants had possible/likely neuropathic pain (possible n=19, [19.4%], likely n=11 [11.2%]). The most common neuropathic symptoms were sensitivity to pressure (56%), sudden pain attacks/electric shocks (36%) and burning (25%). Compared to those with unlikely neuropathic pain, those with possible/likely neuropathic pain were significantly older (d=0.59, p=0.010), had worse SF12 physical (d=1.10, p<0.001), pain self-efficacy (d=0.98, p<0.001), FHSQ pain (d=0.98, p<0.001) and FHSQ function (d=0.82, p<0.001) scores, and had higher pain severity at rest (d=1.01, p<0.001). CONCLUSION: A significant proportion of individuals with first MTP joint OA report symptoms suggestive of neuropathic pain, which may partly explain the suboptimal responses to commonly used treatments for this condition. Screening for neuropathic pain may assist in the selection of targeted interventions and improve clinical outcomes