Intraoperative length and tension curves of human eye muscles. Including stiffness in passive horizontal eye movement in awake volunteers

Intraoperative continuous-registration length and tension curves of attached and detached eye muscles were made in 18 strabismic patients under general anesthesia. For relaxed eye muscles, we found an exponential relation between length and tension. An increased stiffness was quantified in Duane's syndrome, Graves' disease, orbital-floor fracture, and superior oblique palsy. The stiffnesses of agonist and antagonist were remarkably similar, not only in uncomplicated squint, but also when only one of the two had initially become stiffer. After intravenous administration of succinylcholine chloride, the eye muscles contracted, and the exponential length and tension curve changed into a set of straight, parallel lines. In addition, we measured stiffness in passive horizontal eye movement in awake volunteers and found 0.52 to 1.26 g/degrees (other eye in 5° of adduction), confirming other published results

Length-tension curves of human eye muscles during succinylcholine-induced contraction

We have made intraoperative, continuous-registration, length-tension diagrams of detached eye muscles in 80 strabismus patients under general anaesthesia. In 47 of these we repeated the measurements after contraction evoked by succinylcholine chloride. In contracting horizontal and vertical rectus muscles, we found a linear relation between length and tension. In contracting oblique muscles, however, the relation between length and tension was frequently nonlinear. In superior oblique palsies, the superior oblique was found to be stiff after elongation and before injection of succinylcholine, and it did not contract after injection of succinylcholine. The ipsilateral inferior oblique did contract after injection of succinylcholine, but with a higher spring constant than usual (ie, contracture of the ipsilateral antagonist). In three cases the superior oblique contracted vividly after administration of succinylcholine despite the presence of excyclotropia, stereopsis, torticollis (two cases) and a hypertropia that increased in adduction, in down-gaze, in adduction and down-gaze and on ipsilateral head-tilt. In a case of general fibrosis syndrom we found almost normally contracting vertical recti, which is compatible only with a supranuclear or misdirectional cause. These cases demonstrate the usefulness of the assessment of the length-tension diagram of an eye muscle during surgery, before and during contraction evoked by succinylcholine chloride

A novel foil flip-over system as the final layer in wound closure: Excellent cosmetic results and patient comfort

Background Wound closure after excision is commonly done with sutures or staples. A new sutureless innovative wound closure system is available for sutureless skin closure. Objective To evaluate wound healing, patient comfort, and cosmetic results of a foil flip-over system for excision of small skin lesion. Materials and Methods Patients presenting to the department of Dermatology of Erasmus University Medical Center, Rotterdam, The Netherlands for skin surgery during a 1.5-year period were prospectively studied. Key outcome measures were wound healing, patient comfort, and cosmetic results. Three independent physicians scored photographs of the scars. Evaluation tools used were comfort and body image questionnaires and visual analogue scales. Results Ninety-six patients with 103 lesions were included in our study. The surgeon scored wound healing as excellent or good in 96%. No wound infections occurred. Ninety-two percent of patients scored removal of the system as comfortable. Median patient grade of scar after 1 month was 8 out of 10 points (interquartile range [IQR] 7-9). Median independent physician grade of photographs of the scars was 7.7 (IQR 7.1-8.0). Conclusion Sutureless foil flip-over is promising, with excellent patient comfort characteristics and good to excellent cosmetic results

Measurement of Leading Proton and Neutron Production in Deep Inelastic Scattering at HERA

Deep--inelastic scattering events with a leading baryon have been detected by the H1 experiment at HERA using a forward proton spectrometer and a forward neutron calorimeter. Semi--inclusive cross sections have been measured in the kinematic region 2 <= Q^2 <= 50 GeV^2, 6.10^-5 <= x <= 6.10^-3 and baryon p_T <= MeV, for events with a final state proton with energy 580 <= E' <= 740 GeV, or a neutron with energy E' >= 160 GeV. The measurements are used to test production models and factorization hypotheses. A Regge model of leading baryon production which consists of pion, pomeron and secondary reggeon exchanges gives an acceptable description of both semi-inclusive cross sections in the region 0.7 <= E'/E_p <= 0.9, where E_p is the proton beam energy. The leading neutron data are used to estimate for the first time the structure function of the pion at small Bjorken--x.Comment: 30 pages, 9 figures, 2 tables, submitted to Eur. Phys.

The geology and geophysics of Kuiper Belt object (486958) Arrokoth

The Cold Classical Kuiper Belt, a class of small bodies in undisturbed orbits beyond Neptune, are primitive objects preserving information about Solar System formation. The New Horizons spacecraft flew past one of these objects, the 36 km long contact binary (486958) Arrokoth (2014 MU69), in January 2019. Images from the flyby show that Arrokoth has no detectable rings, and no satellites (larger than 180 meters diameter) within a radius of 8000 km, and has a lightly-cratered smooth surface with complex geological features, unlike those on previously visited Solar System bodies. The density of impact craters indicates the surface dates from the formation of the Solar System. The two lobes of the contact binary have closely aligned poles and equators, constraining their accretion mechanism

Constraints on axionlike particles with H.E.S.S. from the irregularity of the PKS 2155-304 energy spectrum

Axionlike particles (ALPs) are hypothetical light (sub-eV) bosons predicted in some extensions of the Standard Model of particle physics. In astrophysical environments comprising high-energy gamma rays and turbulent magnetic fields, the existence of ALPs can modify the energy spectrum of the gamma rays for a sufficiently large coupling between ALPs and photons. This modification would take the form of an irregular behavior of the energy spectrum in a limited energy range. Data from the H.E.S.S. observations of the distant BL Lac object PKS 2155-304 (z=0.116) are used to derive upper limits at the 95% C.L. on the strength of the ALP coupling to photons, ggammaa<2.1×10-11GeV-1 for an ALP mass between 15 and 60 neV. The results depend on assumptions on the magnetic field around the source, which are chosen conservatively. The derived constraints apply to both light pseudoscalar and scalar bosons that couple to the electromagnetic fieldFil: Medina, Maria Clementina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto Argentino de Radioastronomia (i); ArgentinaFil: H.E.S. S. collaboration

Sex and age-specific interactions of coronary atherosclerotic plaque onset and prognosis from coronary computed tomography

AimsThe totality of atherosclerotic plaque derived from coronary computed tomography angiography (CCTA) emerges as a comprehensive measure to assess the intensity of medical treatment that patients need. This study examines the differences in age onset and prognostic significance of atherosclerotic plaque burden between sexes.Methods and resultsFrom a large multi-center CCTA registry the Leiden CCTA score was calculated in 24 950 individuals. A total of 11 678 women (58.5 ± 12.4 years) and 13 272 men (55.6 ± 12.5 years) were followed for 3.7 years for major adverse cardiovascular events (MACE) (death or myocardial infarction). The age where the median risk score was above zero was 12 years higher in women vs. men (64–68 years vs. 52–56 years, respectively, P 20: HR 6.71 (4.36–10.32) in women, and score 6–20: HR 1.64 (1.29–2.08); score > 20: HR 2.38 (1.73–3.29) in men. The risk was significantly higher for women within the highest score group (adjusted P-interaction = 0.003). In pre-menopausal women, the risk score was equally predictive and comparable with men. In post-menopausal women, the prognostic value was higher for women [score 6–20: HR 2.21 (1.57–3.11); score > 20: HR 6.11 (3.84–9.70) in women; score 6–20: HR 1.57 (1.19–2.09); score > 20: HR 2.25 (1.58–3.22) in men], with a significant interaction for the highest risk group (adjusted P-interaction = 0.004).ConclusionWomen developed coronary atherosclerosis approximately 12 years later than men. Post-menopausal women within the highest atherosclerotic burden group were at significantly higher risk for MACE than their male counterparts, which may have implications for the medical treatment intensity.</div

Prognostic significance of nonobstructive left main coronary artery disease in patients with and without diabetes: long-term outcomes from the CONFIRM registry

BackgroundPrognostic significance of non-obstructive left main (LM) disease was recently reported. However, the influence of diabetes mellitus (DM) on event rates in patients with and without non-obstructive LM disease is not well-known.MethodsWe evaluated 27,252 patients undergoing coronary computed tomographic angiography from the COroNary CT Angiography Evaluation For Clinical Outcomes: An InteRnational Multicenter (CONFIRM) Registry. Cumulative long-term incidence of all-cause mortality (ACM) was assessed between DM and non-DM patients by normal or non-obstructive LM disease (1–49% stenosis).ResultsThe mean age of the study population was 57.612.6 years. Of the 27,252 patients, 4,434 (16%) patients had DM. A total of 899 (3%) deaths occurred during the follow-up of 3.6±1.9. years. Compared to patients with normal LM, those with non-obstructive LM had more pronounced overall coronary atherosclerosis and more cardiovascular risk factors. After clinical risk factors, segment involvement score, and stenosis severity adjustment, compared to patients without DM and normal LM, patients with DM were associated with increased ACM regardless of normal (HR 1.48, 95% CI 1.22–1.78, pConclusionFrom the CONFIRM registry, we demonstrated that DM was associated with increased ACM. However, the presence of non-obstructive LM was not an independent risk marker of ACM, and there was no significant interaction between DM and non-obstructive LM disease for ACM.Cardiolog