Residence time and collision statistics for exponential flights: the rod problem revisited

Many random transport phenomena, such as radiation propagation, chemical/biological species migration, or electron motion, can be described in terms of particles performing {\em exponential flights}. For such processes, we sketch a general approach (based on the Feynman-Kac formalism) that is amenable to explicit expressions for the moments of the number of collisions and the residence time that the walker spends in a given volume as a function of the particle equilibrium distribution. We then illustrate the proposed method in the case of the so-called {\em rod problem} (a 1d system), and discuss the relevance of the obtained results in the context of Monte Carlo estimators.Comment: 9 pages, 8 figure

The role of the osteoplastic flap in the endoscopic era : a retrospective multicentre experience on revision surgery

Objective. To retrospectively review the experience of five tertiary-care university hospitals on frontal sinus revision surgery with osteoplastic flap (OPF). Methods. Descriptive analysis of patients who underwent frontal sinus surgery with OPF after one or more endoscopic procedures for benign and inflammatory pathologies from 2000 to 2022. Clinical charts were reviewed for demographics, indications, clinical presen-tation, previous frontal procedures, OPF technique and outcomes. Results. Of the 124 patients who underwent an OPF procedure, 33 met inclusion criteria. With a mean of 2.1 previous endoscopic surgeries, Draf III was the most common former procedure. In 30 (91%) cases OPF was part of a combined procedure. The most common indications were inverted papilloma (61%), mucocele (9%) and chronic rhinosinusitis (6%). Frontal outflow stenosis (36%) and mucocele (9%) were the most frequent complications observed. Improvement of overall symptoms and patient satisfaction after the OPF procedure were recorded. Conclusions. Even in the endoscopic era, OPF still represents a paramount procedure that should be included in the rhino-surgeon’s armamentarium, in particular in patients with challenging pathologies and anatomy when previous endoscopic endonasal attempts have failed

Multicentre translational Trial of Remote Ischaemic Conditioning in Acute Ischaemic Stroke (TRICS): Protocol of multicentre, parallel group, randomised, preclinical trial in female and male rat and mouse from the Italian Stroke Organization (ISO) Basic Science network

INTRODUCTION: Multicentre preclinical randomised controlled trials (pRCT) are emerging as a necessary step to confirm efficacy and improve translation into the clinic. The aim of this project is to perform two multicentre pRCTs (one in rats and one in mice) to investigate the efficacy of remote ischaemic conditioning (RIC) in an experimental model of severe ischaemic stroke. METHODS AND ANALYSIS: Seven research laboratories within the Italian Stroke Organization (ISO) Basic Science network will participate in the study. Transient endovascular occlusion of the proximal right middle cerebral artery will be performed in two species (rats and mice) and in both sexes. Animals will be randomised to receive RIC by transient surgical occlusion of the right femoral artery, or sham surgery, after reperfusion. Blinded outcome assessment will be performed for dichotomised functional neuroscore (primary endpoint) and infarct volume (secondary endpoint) at 48 hours. A sample size of 80 animals per species will yield 82% power to detect a significant difference of 30% in the primary outcome in both pRCTs. Analyses will be performed in a blind status and according to an intention-to-treat paradigm. The results of this study will provide robust, translationally oriented, high-quality evidence on the efficacy of RIC in multiple species of rodents with large ischaemic stroke. ETHICS AND DISSEMINATION: This is approved by the Animal Welfare Regulatory Body of the University of Milano Bicocca, under project license from the Italian Ministry of Health. Trial results will be subject to publication according to the definition of the outcome presented in this protocol. TRIAL REGISTRATION NUMBER: PCTE0000177

An Improved Technique for Chromosomal Analysis of Human ES and iPS Cells

Prolonged in vitro culture of human embryonic stem (hES) cells can result in chromosomal abnormalities believed to confer a selective advantage. This potential occurrence has crucial implications for the appropriate use of hES cells for research and therapeutic purposes. In view of this, time-point karyotypic evaluation to assess genetic stability is recommended as a necessary control test to be carried out during extensive ‘passaging’. Standard techniques currently used for the cytogenetic assessment of ES cells include G-banding and/or Fluorescence in situ Hybridization (FISH)-based protocols for karyotype analysis, including M-FISH and SKY. Critical for both banding and FISH techniques are the number and quality of metaphase spreads available for analysis at the microscope. Protocols for chromosome preparation from hES and human induced pluripotent stem (hiPS) cells published so far appear to differ considerably from one laboratory to another. Here we present an optimized technique, in which both the number and the quality of chromosome metaphase spreads were substantially improved when compared to current standard techniques for chromosome preparations. We believe our protocol represents a significant advancement in this line of work, and has the required attributes of simplicity and consistency to be widely accepted as a reference method for high quality, fast chromosomal analysis of human ES and iPS cells

Chronic productive cough in young adults is very often due to chronic rhino-sinusitis

Background. Chronic productive cough is a common clinical problem; often potential causes outside the lower respiratory tract are forgotten or ignored. The aim of this study was to make a precise etiopathogenetic diagnosis of chronic productive cough in young adults. Methods. In a clinical setting, 212 subjects (mean age 41±5 years) who had reported chronic productive cough in a previous postal survey of a young adult population underwent within two years clinical and functional investigations following a rational diagnostic approach. Two pulmonologists independently established the diagnosis using a clinically structured interview on nasal and respiratory symptoms, spirometry and other tests when appropriate (bronchodilator test or methacholine bronchial challenge, chest radiography); if rhino-sinusitis was suspected, subjects underwent an ENT examination with nasal endoscopy and/or sinus computed tomography. Results. At the end of the diagnostic procedure, 87 subjects (41%) no longer had chronic productive cough and had normal function. Fifty-eight subjects (27%) had chronic rhino-sinusitis; seventeen subjects (8%) had asthma, and of these fourteen also had chronic rhino-sinusitis; 50 subjects (24%) had COPD stage 0+, of these seven also had chronic rhino-sinusitis. Chronic rhino-sinusitis was more frequent in females than in males (p<0.05). Conclusions. Both in clinical practice and in epidemiological studies, it is important to consider that the origin of chronic productive cough could be frequently outside the lower respiratory tract; a consistent percentage of young adults with persistent productive cough has indeed chronic rhino-sinusitis

Feynman-Kac equation for anomalous processes with space-and time-dependent forces

Invited contribution to the J. Phys. A special issue Emerging Talent

Grasping Kinematics from the Perspective of the Individual Digits: A Modelling Study

Grasping is a prototype of human motor coordination. Nevertheless, it is not known what determines the typical movement patterns of grasping. One way to approach this issue is by building models. We developed a model based on the movements of the individual digits. In our model the following objectives were taken into account for each digit: move smoothly to the preselected goal position on the object without hitting other surfaces, arrive at about the same time as the other digit and never move too far from the other digit. These objectives were implemented by regarding the tips of the digits as point masses with a spring between them, each attracted to its goal position and repelled from objects' surfaces. Their movements were damped. Using a single set of parameters, our model can reproduce a wider variety of experimental findings than any previous model of grasping. Apart from reproducing known effects (even the angles under which digits approach trapezoidal objects' surfaces, which no other model can explain), our model predicted that the increase in maximum grip aperture with object size should be greater for blocks than for cylinders. A survey of the literature shows that this is indeed how humans behave. The model can also adequately predict how single digit pointing movements are made. This supports the idea that grasping kinematics follow from the movements of the individual digits

Effect of clinical signs, endocrinopathies, timing of surgery, hyperlipidemia, and hyperbilirubinemia on outcome in dogs with gallbladder mucocele

Gallbladder mucocele (GBM) is a common extra-hepatic biliary syndrome in dogs with death rates ranging from 7 to 45%. Therefore, the aim of this study was to identify the association of survival with variables that could be utilized to improve clinical decisions. A total of 1194 dogs with a gross and histopathological diagnosis of GBM were included from 41 veterinary referral hospitals in this retrospective study. Dogs with GBM that demonstrated abnormal clinical signs had significantly greater odds of death than subclinical dogs in a univariable analysis (OR, 4.2; 95% CI, 2.14–8.23; P < 0.001). The multivariable model indicated that categorical variables including owner recognition of jaundice (OR, 2.12; 95% CI, 1.19–3.77; P = 0.011), concurrent hyperadrenocorticism (OR 1.94; 95% CI, 1.08–3.47; P = 0.026), and Pomeranian breed (OR, 2.46; 95% CI 1.10–5.50; P = 0.029) were associated with increased odds of death, and vomiting was associated with decreased odds of death (OR, 0.48; 95% CI, 0.30–0.72; P=0.001). Continuous variables in the multivariable model, total serum/plasma bilirubin concentration (OR, 1.03; 95% CI, 1.01– 1.04; P < 0.001) and age (OR, 1.17; 95% CI, 1.08–1.26; P < 0.001), were associated with increased odds of death. The clinical utility of total serum/plasma bilirubin concentration as a biomarker to predict death was poor with a sensitivity of 0.61 (95% CI, 0.54–0.69) and a specificity of 0.63 (95% CI, 0.59–0.66). This study identified several prognostic variables in dogs with GBM including total serum/plasma bilirubin concentration, age, clinical signs, concurrent hyperadrenocorticism, and the Pomeranian breed. The presence of hypothyroidism or diabetes mellitus did not impact outcome in this study

A multivariate analysis of serum nutrient levels and lung function

<p>Abstract</p> <p>Background</p> <p>There is mounting evidence that estimates of intakes of a range of dietary nutrients are related to both lung function level and rate of decline, but far less evidence on the relation between lung function and objective measures of serum levels of individual nutrients. The aim of this study was to conduct a comprehensive examination of the independent associations of a wide range of serum markers of nutritional status with lung function, measured as the one-second forced expiratory volume (FEV₁).</p> <p>Methods</p> <p>Using data from the Third National Health and Nutrition Examination Survey, a US population-based cross-sectional study, we investigated the relation between 21 serum markers of potentially relevant nutrients and FEV₁, with adjustment for potential confounding factors. Systematic approaches were used to guide the analysis.</p> <p>Results</p> <p>In a mutually adjusted model, higher serum levels of antioxidant vitamins (vitamin A, beta-cryptoxanthin, vitamin C, vitamin E), selenium, normalized calcium, chloride, and iron were independently associated with higher levels of FEV₁. Higher concentrations of potassium and sodium were associated with lower FEV₁.</p> <p>Conclusion</p> <p>Maintaining higher serum concentrations of dietary antioxidant vitamins and selenium is potentially beneficial to lung health. In addition other novel associations found in this study merit further investigation.</p

Seeing touches early in life

Addabbo M, Longhi E, Bolognini N, et al. Seeing touches early in life. PLoS ONE. 2015;10(9): e0134549