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Chitosan and its derivatives are interesting biopolymers for different field of analytical chemistry, especially in separation techniques. The present study was aimed at testing chitosan water soluble derivatives as dynamic coating agents for application to capillary electrophoresis. In particular, chitosan was modified following three different chemical reactions (nucleophilic substitution, reductive amination, and condensation) to introduce differences in charge and steric hindrance, and to assess the effect of these physico-chemical properties in capillary electrophoresis. The effects were tested on the capillary electrophoretic separation of the glycoforms of human transferrin, an important iron-transporting serum protein, one of which, namely disialo-transferrin (CDT), is a biomarker of alcohol abuse. Chitosan derivatives were characterized by using NMR and 1H NMR, HP-SEC-TDA, DLS, and rheology. The use of these compounds as dynamic coatings in the electrolyte running buffer in capillary electrophoresis was tested assessing the peak resolution of the main glycoforms of human transferrin and particularly of disialo-transferrin. The results showed distinct changes of the peak resolution produced by the different derivatives. The best results in terms of peak resolution were achieved using polyethylene glycol (PEG)-modified chitosan, which, in comparison to a reference analytical approach, provided an almost baseline resolution of disialo-transferrin from the adjacent peaks.

The substitution of perfluorinated substances (PFAS) as chemical applied in anti-adhesive and hydrophobic applications has become an urgent need, due to raising concerns for their potential hazard. In this framework, chitosan-based coatings represent a promising alternative because of their properties of non-toxicity, biodegradability, and sustainability as raw materials. Our work developed modified chitosan-based coatings, with a fine-tuning of transparency and superhydrophobicity (Figure 1). Chitosan-based fluorine-free superhydrophobic coatings were obtained via functionality modification through esterification and amidation reaction with stearoyl chloride, followed by freeze-drying and coating deposition using a novel solvent-free approach followed by thermal treatment. A full characterization of the modified-chitosan was performed to assess its chemico-physical properties and confirmed the functionality modification. The application of an innovative and sustainable deposition method demonstrates to be effective in tuning the coating properties of transparency and superhydrophobicity, combining durability under physical abrasion.

Protein analysis by capillary electrophoresis is an established benchmark technique, where electrophoretic separation performances are frequently affected by protein adsorption on capillary walls. The protein-wall interaction can be suppressed or mitigated by the application of the so-called dynamic coating agents. In this study, the potential of chitosan derivatives as dynamic coating was investigated, targeting the separation of the carbohydrate deficient transferrin (CDT), a relevant biomarker in forensic analyses to detect chronic alcohol abuse. To this aim, chitosan was derivatized through different chemical reactions, including nucleophilic substitution, reductive amination, and condensation reaction, to provide different characteristics to the dynamic coatings. After chemical and physical characterization, chitosan derivatives were tested as dynamic coating additives in the buffer separation solution of CDT. Evidence of the improvement in the CDT separation efficiency were found applying PEGmodified chitosan via nucleophilic substitution.

One of the current greatest challenges in materials science and technology is the development of safe- and sustainable-by-design coatings with enhanced functionalities, e.g. to substitute fluorinated substances raising concerns for their potential hazard on human health. Bio-based polymeric coatings represent a promising route with a high potential. In this study, we propose an innovative sustainable method for fabricating coatings based on chitosan with modified functionality, with a fine-tuning of coating properties, namely transparency and superhydrophobicity. The process consists in two main steps: i) fluorine-free modification of chitosan functional groups with stearoyl chloride and freeze-drying to obtain a superhydrophobic powder, ii) coating deposition using a novel solvent-free approach through a thermal treatment. The modified chitosan is characterized to assess its chemico-physical properties and confirm the functionality modification with fatty acid tails. The deposition method enables tuning the coating properties of transparency and superhydrophobicity, maintaining good durability.

OBJECTIVES: To describe the characteristics and outcomes of patients with COVID-19 admitted to intensive care units (ICUs) during the initial months of the pandemic in Australia. DESIGN, SETTING: Prospective, observational cohort study in 77 ICUs across Australia. PARTICIPANTS: Patients admitted to participating ICUs with laboratory-confirmed COVID-19 during 27 February - 30 June 2020. MAIN OUTCOME MEASURES: ICU mortality and resource use (ICU length of stay, peak bed occupancy). RESULTS: The median age of the 204 patients with COVID-19 admitted to intensive care was 63.5 years (IQR, 53-72 years); 140 were men (69%). The most frequent comorbid conditions were obesity (40% of patients), diabetes (28%), hypertension treated with angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers (24%), and chronic cardiac disease (20%); 73 patients (36%) reported no comorbidity. The most frequent source of infection was overseas travel (114 patients, 56%). Median peak ICU bed occupancy was 14% (IQR, 9-16%). Invasive ventilation was provided for 119 patients (58%). Median length of ICU stay was greater for invasively ventilated patients than for non-ventilated patients (16 days; IQR, 9-28 days v 3 days; IQR, 2-5 days), as was ICU mortality (26 deaths, 22%; 95% CI, 15-31% v four deaths, 5%; 95% CI, 1-12%). Higher Acute Physiology and Chronic Health Evaluation II (APACHE-II) scores on ICU day 1 (adjusted hazard ratio [aHR], 1.15; 95% CI, 1.09-1.21) and chronic cardiac disease (aHR, 3.38; 95% CI, 1.46-7.83) were each associated with higher ICU mortality. CONCLUSION: Until the end of June 2020, mortality among patients with COVID-19 who required invasive ventilation in Australian ICUs was lower and their ICU stay longer than reported overseas. Our findings highlight the importance of ensuring adequate local ICU capacity, particularly as the pandemic has not yet ended.

BACKGROUND: Lung cancer management is characterised by a high disease burden, poor survival and substantial variation in management and outcomes. Service redesign provides opportunities for quality improvement (QI) and this improvement may be leveraged across multiple sites using QI collaboration. AIM: This initiative targeted Quality Improvement (QI) in lung cancer management, engaging a QI collaborative using service redesign methodologies in five Victorian hospitals. QI targets included timeliness from referral and diagnosis to treatment, multi-disciplinary meeting (MDM) presentation and supportive care screening. Redesign strategies targeted process sustainability through enhanced team capability. METHODS: This study engaged a prospective quality improvement cohort design targeting newly diagnosed tissue confirmed lung cancer with 6-month pre-intervention period and 6-month redesign implementation period, between September 2016 and August 2017, evaluated using Interrupted Time Series Analysis. Hospital sites included three regional and two metropolitan hospitals in Victoria. QI redesign targeted time intervals from referral to first specialist appointment (FSA), referral to diagnosis, diagnosis to first treatment (any intent), MDM documented in medical records and Supportive Care Screening Tool documented in medical records. RESULTS: There was a marked reduction in referral to FSA interval across all sites, with median (interquartile range) falling from 6 (0-15) to 4 (1-10) days, and proportion seen by a specialist within 14 days increased from 74.3% to 84.2%. The interval between diagnosis and treatment was not substantively changed in the 6-month implementation period. The proportion of subjects with documented presentation to the MDM increased from 61% to 67%. The proportion for which Supportive Care Screening documentation remained low at 26.3% post-intervention. CONCLUSIONS: Data-driven redesign initiatives enable identification and analysis of clinical pra

Cross-country (XC) ski races involve a variety of formats, two different techniques and tracks with highly variable topography and environmental conditions. In addition, XC skiing is a major component of both Nordic combined and biathlon competitions. Research in this area, both in the laboratory and field, encounters certain difficulties that may reduce the reliability and validity of the data obtained, as well as complicate comparisons between studies. Here, 13 international experts propose specific guidelines designed to enhance the quality of research and publications on XC skiing, as well as on the biathlon and Nordic combined skiing. We consider biomechanical (kinematic, kinetic and neuromuscular) and physiological methodology (at the systemic and/or muscle level), providing recommendations for standardization/control of the experimental setup. We describe the types of measuring equipment and technology that are most suitable in this context. Moreover, we also deal with certain aspects of nomenclature of the classical and skating sub-techniques. In addition to enhancing the quality of studies on XC skiing, Nordic combined and biathlon, our guidelines should also be of value for sport scientists and coaches in other disciplines where physiological and/or biomechanical measurements are performed in the laboratory and/or outdoors.

Valentina Muollo,1,2 Andrea P Rossi,3 Chiara Milanese,1 Elena Masciocchi,3 Miriam Taylor,3 Mauro Zamboni,3 Raffaela Rosa,1 Federico Schena,1,2 Barbara Pellegrini1,21Department of Neurosciences, Biomedicine, and Movement Sciences, University of Verona, Verona, Italy; 2CeRiSM, Sport Mountain and Health Research Centre, University of Verona, Rovereto, Italy; 3Department of Medicine, Section of Geriatrics, University of Verona Healthy Aging Center, Verona, ItalyCorrespondence: Valentina MuolloDepartment of Neurosciences, Biomedicine, and Movement Sciences, University of Verona, Verona, ItalyTel +39 045 842 5122Fax +39 045 842 5131Email valentina.muollo@univr.itPurpose: Nordic walking (NW) has been recommended as a form of exercise for clinical populations. Despite intervention programs designed to face a clinical status may last several months, no longitudinal studies have compared the effect of NW to another usual form of exercise, like walking (W). We evaluated the effects of diet combined with a long-supervised NW versus W training on body composition, aerobic capacity and strength in overweight adults.Patients and methods: Thirty-eight participants, randomized into a NW (n=19, 66±7 years, body mass index (BMI) 33±5)) and a W (n=19, 66±8 years, BMI 32±5) group, followed a diet and a supervised training routine 3 times/week for 6 months. The variables assessed at baseline, after 3 and 6 months were: anthropometric indexes (ie, BMI and waist circumference (WC)), body composition, aerobic capacity (oxygen consumption (VO2peak), peak power output (PPO), 6-min walking test (6MWT)) and strength (maximal voluntary contraction of biceps brachialis (MVCBB) and quadriceps femoris (MVCQF), chair stand and arm curl (AC)).Results: After 6 months both NW and W group decreased significantly BMI (6% and 4%, respectively) and WC (8% and 4%, respectively), but only the NW group reduced (P<0.05) total body fat (8%), android fat (14%) a