Facile and Bioinspired Approach from Gallic Acid for the Synthesis of Biobased Flame Retardant Coatings of Basalt Fibers

A sustainable, bioinspired approach to functionalize basalt fibers with an innovative gallic acid (GA)-iron phenyl phosphonate complex (BF-GA-FeP), for the purpose of improving the flame retardancy in composite materials, is developed. BFs were at first pretreated with O3, obtaining surface free hydroxyl groups that allowed the subsequent covalent immobilization of biosourced GA units on the fiber through ester linkages. Phenolic -OH groups of the GA units were then exploited for the complexation of iron phenyl phosphonate, resulting in the target-complex-coated BF fiber (BF-GA-FeP). Microwave plasma atomic emission spectroscopy and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy analyses of BF-GA-FeP highlighted an increase in iron content, modification of fiber morphology, and occurrence of phosphorus, respectively. BFs, modified with a low amount of the developed complex, were used to reinforce a poly(lactic acid) (PLA) matrix in the production of a biocomposite (PLA/BF-FeP). PLA/BF-FeP showed a higher thermal stability than neat PLA and PLA reinforced with untreated BFs (PLA/BF), as confirmed by thermogravimetric analysis. The cone calorimeter test highlighted several advantages for PLA/BF-FeP, including a prolonged time to ignition, a reduced time to flame out, an 8% decrease in the peak heat release rate, and a 15% reduced fire propagating index compared to PLA/BF.

An Event-based Neural Compressive Telemetry with >11× Loss-less Data Reduction for High-bandwidth Intracortical Brain Computer Interfaces

Intracortical brain-computer interfaces offer superior spatial and temporal resolutions, but face challenges as the increasing number of recording channels introduces high amounts of data to be transferred. This requires power-hungry data serialization and telemetry, leading to potential tissue damage risks. To address this challenge, this paper introduces an event-based neural compressive telemetry (NCT) consisting of 8 channel-rotating Δ-ADCs, an event-driven serializer supporting a proposed ternary address event representation protocol, and an event-based LVDS driver. Leveraging a high sparsity of extracellular spikes and high spatial correlation of the high-density recordings, the proposed NCT achieves a compression ratio of >11.4×, while consumes only 1 μW per channel, which is 127× more efficient than state of the art. The NCT well preserves the spike waveform fidelity, and has a low normalized RMS error <23% even with a spike amplitude down to only 31 μV.

Etiology, presentation and management of urinary tract infections in multiple sclerosis patients: A review of the current literature

Urinary tract infections (UTIs) present a formidable challenge in the care of individuals affected by multiple sclerosis (MS). Lower urinary tract dysfunction is a prevalent issue among MS patients, predisposing them to an elevated risk of UTIs. When left untreated, UTIs can further exacerbate the already compromised quality of life in individuals with MS. The diagnosis and management of UTIs in MS patients necessitate a careful clinical evaluation. The objective of this review is to delineate preventive strategies and current and developing therapeutic approaches for preventing and treating UTIs associated with urinary dysfunction, catheterization, and upper urinary tract infections in patients with MS. Effectively addressing UTIs and urinary tract dysfunction in individuals with multiple sclerosis calls for a comprehensive, interdisciplinary approach.

Survey on the interest and commitment of AIFM members to scientific activities (SicAS) - The initiative of the FutuRuS working group

PURPOSE

The "FutuRuS" working group of the Italian Association of Medical Physics and Health Physics (AIFM) designed a survey (SicAS) to get feedback from its members regarding their interests and their experience in taking part in scientific activities and events, with the objective of focusing future efforts of the AIFM towards increasing the scientific activity of the medical physics expert (MPE).

METHODS

SicAS was sent out in March 2022 to all AIFM members by newsletter and official communication. SicAS was structured into three sections: personal information and institution of affiliation information, involvement in scientific activities, interest in and commitment to scientific activities. Responses were collected in a fully anonymised mode from the Google Forms platform and analysed with descriptive statistics.

RESULTS

Out of 1289 members (active at the end of 2021), 467 responded to the Survey (response rate of 36%). The Survey results highlighted that AIFM members ranked the involvement of the MPE in scientific activities as highly relevant to the profession. However, 34.7% indicated devoting less than 10% of their working time to scientific activities. 67.5% of the respondents were dissatisfied with the time spent on scientific activities. The primary barrier was the lack of time (77%), followed by a lack of mentoring (32%).

CONCLUSIONS

SicAS highlighted the need for AIFM initiatives to support members' scientific activities. National societies should help develop and support networks between members, create links among universities, hospitals, research institutions and industries, and provide guidelines and learning platforms for enhancing the MPEs' involvement in scientific activities.

Infrared Imaging Analysis of Green Composite Materials during Inline Quasi-Static Flexural Test: Monitoring by Passive and Active Approaches

Composite materials have been used for many years in a wide variety of sectors starting from aerospace and nautical up to more commonly used uses such as bicycles, glasses, and so on. The characteristics that have made these materials popular are mainly their low weight, resistance to fatigue, and corrosion. In contrast to the advantages, however, it should be noted that the manufacturing processes of composite materials are not eco-friendly, and their disposal is rather difficult. For these reasons, in recent decades, the use of natural fibers has gained increasing attention, allowing the development of new materials sharing the same advantages with conventional composite systems while respecting the environment. In this work, the behavior of totally eco-friendly composite materials during flexural tests has been studied through infrared (IR) analysis. IR imaging is a well-known non-contact technique and represents a reliable means of providing low-cost in situ analysis. According to this method, the surface of the sample under investigation is monitored, under natural conditions or after heating, by recording thermal images with an appropriate IR camera. Here, the results achieved for jute- and basalt-based eco-friendly composites through the use of both passive and active IR imaging approaches are reported and discussed, showing the possibilities of use also in an industrial environment.

Endoscopic "retrograde" dacryocystorhinostomy: A fast route to the lacrimal sac

Endoscopic Dacryocystorhinostomy (DCR) is an established surgical technique for the management of peripheral nasolacrimal duct (NLD) obstruction. Its main points are the correct identification of the lacrimal sac and the execution of surgical procedures that allow a rapid and accurate healing of the surgical field. The main endoscopic landmarks used for the identification of the lacrimal sac are the middle turbinate and the maxillary line. However, in some cases, this procedure can be difficult due to several factors (e.g. anatomical variations, former surgery). In the present study, a variation of "classic" endoscopic DCR, named "retrograde" endoscopic endonasal DCR (rDCR), is described. rDCR is performed through the quick identification of the NLD at the level of the most anterior insertion of the inferior turbinate in the lateral nasal wall. In most cases, at this level only a very thin shell of bone is present (crack point), easily fractured by using blunt angled dissector. The duct is then followed upward along its course by removing the overlying bone in order to correctly identify the lacrimal sac and unequivocally drill along the lacrimal pathway. This technique proved to be a safe, quick and effective procedure, even in patients with difficult anatomy.

AB0118 PORPHYROMONAS GINGIVALIS AMOUNT IN THE TONGUE BIOFILM IS ASSOCIATED WITH EROSIVE ARTHRITIS IN SYSTEMIC LUPUS ERYTHEMATOSUS

Background

Several data have demonstrated the occurrence of erosive arthritis in Systemic Lupus Erythematosus (SLE) patients. However, few studies have focused on the pathogenic mechanisms involved in this feature. The implication of oral pathogens has been proved in Rheumatoid Arthritis: in particular, Porphyromonas gingivalis (Pg), by inducing citrullination, could trigger autoimmune response.

Objectives

We evaluated amount of Pg of the tongue in a cohort of SLE patients with arthritis, focusing on the association with the erosive phenotype.

Methods

SLE patients with arthritis were enrolled. We evaluated the presence of ACPA and RF by using commercially enzyme-linked immunosorbent assay kits. SLEDAI-2k was applied to assess disease activity and DAS28 to assess joint inflammatory status. Erosive damage was evaluated by ultrasound at level of metacarpophalangeal and proximal interphalangeals joints. All subjects underwent a tongue cytologic swab in order to quantify the amount of Pg (real-time PCR). The bacterium expression was obtained from the ratio between the patient’s DNA amount and that obtained from healthy subjects.

Results

The present analysis included 33 SLE patients (M/F 3/30; median age 47 years, IQR 17; median disease duration 216 months, IQR 180). Concerning activity at the time of the enrollment, we found a median DAS28 value of 3.8 (IQR 2.8) and a median SLEDAI-2k of 4 (IQR 5). Twelve patients (36.4%) showed US-detected erosive damage in at least one joint, significantly associated with ACPA positivity (p<0.0001). Furthermore, patients with erosive damage showed significantly higher median DAS28 values in comparison with those without [4 (IQR 3.1) versus 3.2 (IQR 2.1), p=0.03]. Moving on the oral pathogen analysis, we found a mean Pg ratio of 19.7±31.1 (median 6.6, IQR 22.3). When dividing patients according to the presence of erosive damage, we found higher Pg amount in SLE patients with this phenotype in comparison with those without (31.4±44.3 versus 12.9±19.2, p=ns; Figure 1A). Thus, we used Pg mean values as threshold, identifying two groups of patients, namely highPg and lowPg. In a receiver operating characteristic curve analysis (ROC), this threshold resulted in the most sensitive and specific one (sensitivity of 85%; specificity of 50%). As reported in Figure 1B, erosive damage was significantly more frequent in highPg patients in comparison with lowPg (60.0% versus 26.0%, p=0.001). Furthermore, highPg patients showed higher prevalence of skin manifestations, serositis and neurological involvement compared to lowPg patients (p=0.005, p=0.03, p=0.0001, respectively).

Conclusion

The possible contribution of oral microbiota in SLE erosive arthritis was here evaluated for the first time, finding a significant association between erosive damage and higher expression of Pg at tongue level.

Disclosure of Interests

None declared

Automatic radar-based 2-D localization exploiting vital signs signatures

In light of the continuously and rapidly growing senior and geriatric population, the research of new technologies enabling long-term remote patient monitoring plays an important role. For this purpose, we propose a single-input-multiple-output (SIMO) frequency-modulated continuous wave (FMCW) radar system and a signal processing technique to automatically detect the number and the 2-D position (azimuth and range information) of stationary people (seated/lying down). This is achieved by extracting the vital signs signatures of each single individual, separating the Doppler shifts caused by the cardiopulmonary activities from the unwanted reflected signals from static reflectors and multipaths. We then determine the number of human subjects present in the monitored environment by counting the number of extracted vital signs signatures while the 2-D localization is performed by measuring the distance from the radar where the vital signs information is sensed (i.e., locating the thoracic region). We reported maximum mean absolute errors (MAEs) of 0.1 m and 2.29\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^{\circ }$$\end{document}∘ and maximum root-mean-square errors (RMSEs) of 0.12 m and 3.04\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^{\circ }$$\end{document}∘ in measuring respectively the ranges and azimuth angles. The experimental validation demonstrated the ability of the proposed approach in monitoring paired human subjects in a typical office environment.

An improved nonlinear ultrasonic technique for detecting and monitoring impact induced damage in composite plates

An improved technique for sensing damage initiation and progression in thermoplastic resin composite plate specimens is presented in this study. The composite plate specimens are investigated by using a nonlinear ultrasonic (NLU) technique called Sideband Peak Count Index or SPC-I. The technique presented in this paper is an improvement from the previous SPC-I technique. This improved technique provides more reliable and consistent results and can monitor the damage progression over a wide range. In this paper the narrow band SPC-I technique is introduced to replace the conventional wide band SPC-I technique. The method implemented here is improved in three ways. First and foremost the narrow band SPC-I technique is introduced. Secondly, the non-permanently adhered gel coupled Lead-Zirconate-Titanate (PZT) transducers are used to reduce inconsistency in transducer adhesion and manufacturing. Lastly, higher sampling rate equipment is used for better signal resolution and peak counting. The experiments are performed on 4 sets of composite plate specimens fabricated using two composite fiber materials (Glass and Basalt) that have increasing levels of damage. The composite plate specimens were damaged by a falling weight impact machine with increasing impact energy (0 J, 10 J, 20 J and 30 J). The composite plate specimens were examined by propagating a narrow band chirp signal through the specimens using gel coupled transducers in a transmission mode setup. The received signals were recorded and analyzed using the NLU SPC-I technique. The modified SPC-I technique proposed in this paper can reliably and consistently detect both initiation and progression of damage in the composite plate specimens.

Thermal and Quasi-Static Mechanical Characterization of Polyamide 6-Graphene Nanoplatelets Composites

The growing demand for lightweight and multifunctional products in numerous industrial fields has recently fuelled a growing interest in the development of materials based on polymer matrices including graphene-like particles, intrinsically characterized by outstanding mechanical, thermal, and electrical properties. Specifically, with regard to one of the main mass sectors, which is the automotive, there has been a significant increase in the use of reinforced polyamides for underhood applications and fuel systems thanks to their thermal and chemical resistance. In this frame, polyamide 6 (PA6) composites filled with graphene nanoplatelets (GNPs) were obtained by melt-compounding and compared in terms of thermal and mechanical properties with the neat matrix processed under the same condition. The results of the experimental tests have shown that the formulations studied so far offer slight improvements in terms of thermal stability but much more appreciable benefits regarding both tensile and flexural parameters with respect to the reference material. Among these effects, the influence of the filler content on the strength parameter is noteworthy. However, the predictable worsening of the graphene sheet dispersion for GNPs contents greater than 3%, as witnessed by scanning electron images of the tensile fractured sections of specimens, affected the ultimate performance of the more concentrated formulation.

Cross-sectional and longitudinal associations between sleep duration, sleep quality, and bone stiffness in European children and adolescents

In this large perspective cohort among European children and adolescents, we observed that daytime napping was positively associated with bone stiffness, while short or long sleep duration combined with poor sleep quality was associated with less bone stiffness. Our findings are important for obtaining optimal bone stiffness in childhood.

INTRODUCTION

To examine the cross-sectional and longitudinal associations between sleep duration, sleep quality, and bone stiffness index (SI) in European children and adolescents.

METHODS

Four thousand eight hundred seventy-one children aged 2-11 years from the IDEFICS study and 861 children aged 6-15 years from the subsequent I.Family study were included. Sleep duration (i.e., nocturnal sleep and daytime napping) and sleep quality (i.e., irregularly bedtime routine, have difficulty falling asleep and trouble getting up in the morning) were reported by self-administrated questionnaires. Nocturnal sleep duration was converted into age-specific z-scores, and total sleep duration was classified into short, adequate, and long based on the National Sleep Recommendation. Calcaneal SI of both feet were measured using quantitative ultrasound. Linear mixed-effects models with country as a random effect were used, with adjustments for sex, age, pubertal status, family socioeconomic status, physical activity, screen time, body mass index, and daylight duration.

RESULTS

Nocturnal sleep duration z-scores were positively associated with SI percentiles among participants with adequate sleep duration at baseline. Moreover, the positive association between daytime napping and SI percentiles was more pronounced in participants with adequate sleep duration at baseline, while at 4-year follow-up was more pronounced in participants with short sleep duration. In addition, extreme sleep duration at baseline predicted lower SI percentiles after 4 years in participants with poor sleep quality.

CONCLUSION

The positive associations between nocturnal sleep, daytime napping and SI depended on total sleep duration. Long-term detrimental effect of extreme sleep duration on SI only existed in individuals with poor sleep quality.

Flexural Properties and Low-Velocity Impact Behavior of Polyamide 11/Basalt Fiber Fabric Laminates

Environmentally friendly composite plates intended for load-bearing applications were prepared and systematically characterized in terms of mechanical performances and morphological features. Sample plates combining two extrusion grades of bio-polyamide 11, one of which is plasticized, and two basalt fiber fabrics (plain weave and twill architectures) were obtained by film stacking and hot pressing, and their mechanical properties were investigated by quasi-static flexural and low-velocity impact tests. The comparative analysis of the results, also interpreted by the bending damage analysis, through optical microscope observations, and impact damage analysis through visual inspection and indentation measurements demonstrate that, besides interfacial adhesion issues, the mechanical performance of the laminates need to be optimized through a careful selection of the constituents in the light of the final application. In particular, if the goal is a gain in impact strength, the use of the plasticized matrix is beneficial, but it brings about a loss in stiffness and strength that can be partially compensated by properly selecting a more performing fiber fabric architecture. The latter must also be easily permeated by the matrix to enhance the efficiency of stress transfer from the matrix. Overall, our results can be exploited for the development of bio-composites for particularly demanding applications.

Impact of reimbursement limits on patient access to direct-acting antivirals in Italy: analysis of data from national registries

OBJECTIVE

Hepatitis C virus (HCV) infection is a global epidemic, still highly prevalent in Europe. Given efficacy and safety of HCV therapy by Direct Antiviral Agents (DAA), World Health Organization called for actions to eliminate HCV infection. A limit is represented by access to care, mostly due to the high costs of medicines. In Italy, in 2015, the access to DAA therapy was reimbursed for patients with advanced disease, whereas in 2017 universal access was granted. The aim of this study was to analyse changes in patient recruitment trends treated with DAA with or without limitations to access to therapy.

PATIENTS AND METHODS

165,105 patients treated with DAA in Italy from 2015 to December 2018 were analysed. Daily patient treatment rate was obtained by segmented regression of interrupted time series analysis.

RESULTS

74,199 patients with advanced disease (62% with cirrhosis) had access to the therapy during the time period from 2015 to 2017. Following the extension of reimbursement criteria, 90,906 additional patients were treated (43.2% with F0-F1 and 22.9% with F2), with an absolute reduction of 59.9% of patients with advanced disease (cirrhosis decreased to 18.5%). Segmented regression of interrupted time series analysis of daily patient treatment rate showed a progressive reduction of patients with advanced disease, offset by those with initial disease. Notably, elimination of restrictions to therapy did not change the overall treatment rate.

CONCLUSIONS

This study showed that a no-limit reimbursement policy for DAAs prescriptions to HCV infected individuals in Italy widened the types of treated patients, but the process towards elimination of HCV infection was not significantly changed.

Identification and diagnosis of Secondary Progressive Multiple Sclerosis during the clinical encounter: Results from a physician survey

BACKGROUND

It is difficult to characterize the transition from relapsing-remitting multiple sclerosis (RRMS) to secondary progressive MS (SPMS), due to symptomatic variability across patients. Diagnosis of SPMS is prolonged and often established retrospectively, as it is based on patient clinical history and symptoms. This cross-sectional study aimed to identify MS neurologist reported clinical indicators deemed important in diagnosing SPMS in clinical practice.

METHODS

A web-based quantitative survey was conducted among MS-treating neurologists across the United States in January 2019. The questionnaire comprised of 17 questions evaluating primary clinical indicators used by neurologists in assessing patient progression to SPMS. Treatment approach and factors influencing treatment decision-making following SPMS diagnosis were also analyzed in the survey.

RESULTS

Overall, 300 neurologists completed the survey; most of the respondents were general MS-treating neurologists (63%) and from private care setting (58%). The overall respondents as well as MS-focused neurologists ranked patient history (45% and 42%, respectively) and patients' neurological exam (39% and 44%, respectively) as -primary clinical indicators of SPMS diagnosis. 57% of neurologists always or mostly switched disease modifying therapies after progression to SPMS, and mostly considered 3-6 months' assessment interval to diagnose SPMS.

CONCLUSION

The survey indicated that neurologists are able to recognize signs of SPMS within six months of symptomatic assessment. The diagnosis is primarily based on patient history among MS-treating neurologists. Therefore, continued education to neurologists may facilitate early diagnosis and timely introduction of effective treatment to manage the progression of SPMS.

Surface Modification of Basalt Fibres with ZnO Nanorods and Its Effect on Thermal and Mechanical Properties of PLA-Based Composites

The composites based on basalt fibres and poly(lactic acid) (PLA) show promising applications in biomedical and automotive fields, but their mechanical performance is still largely hindered by poor interfacial properties. Zinc oxide nanorods have been successfully used to tune the PLA/basalt fibre interface by growing them on commercially available basalt fabrics. The hierarchical fibres significantly enhanced the mechanical properties of PLA-based composites, especially their flexural strength and stiffness. These values are 26% and 22% higher than those of unmodified basalt/PLA composites, and 24% and 34% higher than those of glass/PLA composites used as a baseline. The increase in tensile and flexural properties hinges on the mechanical interlocking action promoted by ZnO nanorods and on the creation of a compact transcrystallinity structure. A degradation of PLA matrix was detected but it was positively counteracted by the better interfacial stress transfer. This study offers a novel approach for modifying the fibre–matrix interface of biocomposites intended for high-performance applications.

A thermoresponsive gel photoreleasing nitric oxide for potential ocular applications

We report herein the design, preparation, characterization and biological evaluation of a thermoresponsive gel based on binary mixtures of Pluronic® co-polymers F127 and P123, the latter being covalently functionalized with a nitric oxide (NO) photodonor (NOPD). The weight ratio between the two polymeric components is optimized in order to observe gelation of their saline water solution in the range of 32-35 °C, in order to exploit the therapeutic properties of NO for potential ocular applications. Rheological measurements were performed to evaluate the gelation temperature and, hence, to select a co-polymer mixture specifically appropriate for the reference application. Integration of the NOPD into the polymeric scaffold does not affect its rheological and spectroscopic properties, making it a good absorber of visible light both in solution and in the gel phase. Irradiation of the saline solution of the polymeric components with visible light triggers NO release, which occurs with an efficiency of more than one order of magnitude faster than that observed for the isolated NOPD. The polymeric system fully preserves such photobehavior after gelation as demonstrated by the effective NO photorelease from the gel matrix and its diffusion in the supernatant upon illumination. The gel is well-tolerated in both dark and light conditions by corneal cells, while being able to induce growth inhibition towards Staphylococcus aureus under visible light irradiation and has high moduli which can contribute to an adequate retention time within the eyes.

Improving Interaction at Polymer-Filler Interface: The Efficacy of Wrinkle Texture

One of the main issues in preparing polymer-based nanocomposites with effective properties is to achieve a good dispersion of the nanoparticles into the matrix. Chemical interfacial modifications by specific coupling agents represents a good way to reach this objective. Actually, time consuming compatibilization procedures strongly compromise the sustainability of these strategies. In this study, the role of particles' architectures in their dispersion into a poly-lactic acid matrix and their subsequent influences on physical-chemical properties of the obtained nanocomposites were investigated. Two kinds of silica nanoparticles, "smooth" and "wrinkled," with different surface areas (≈30 and ≈600 m2/g respectively) were synthesized through a modified Stöber method and used, without any chemical surface pre-treatments, as fillers to produce poly-lactic acid based nanocomposites. The key role played by wrinkled texture in modifying the physical interaction at the polymer-filler interface and in driving composite properties, was investigated and reflected in the final bulk properties. Detailed investigations revealed the presence of wrinkled nanoparticles, leading to (i) an enormous increase of the chain relaxation time, by almost 30 times compared to the neat PLA matrix; (ii) intensification of the shear-thinning behavior at low shear-rates; and (iii) slightly slower thermal degradation of polylactic acid.

Dose intercomparison at Italian hadrontherapy centers

PURPOSE

To perform the first dosimetric intercomparison for proton beams in Italy using ionization chambers, according to the IAEA TRS-398 code of practice.

METHODS

Measurement sites included: National Center for Oncological Hadron Therapy (CNAO, Pavia), Center for Proton Therapy (CTP, Trento) and Center for Hadron Therapy and for advanced Nuclear Applications (CATANA, Catania). For comparison we also included a 6 MV photon beam produced at Istituti Clinici Scientifici Maugeri (ICSM, Pavia). For proton beams, both single pseudo-monoenergetic layers (in order to obtain a planned dose of 2 Gy at the reference depth of 2 cm in a water phantom) and Spread-out Bragg peaks (SOBP) have been delivered. Measurements were performed with a PTW Farmer 30010-1 and a PTW Advanced Markus type 34,045 ionization chamber.

RESULTS

Data obtained at CATANA, CNAO and CPT in terms of absorbed dose to water depth show good consistency within the experimental uncertainties, with a weighted mean of 1.99 ± 0.01 Gy and a standard error of 0.003 Gy, with reference to a nominal dose of 2 Gy as designed by the treatment planning system.

CONCLUSIONS

The results showed a standard deviation of less than 1% for single layer and SOBP beams, for all chambers and a percent deviation less than 1.5% for single layer measurements. The weighted means of the absorbed doses for clinical proton beams (118.19 MeV and 173.61 MeV) are consistent within less than 1%. These results agree within the 1.5% difference considered acceptable for national dose intercomparison.

Morphology, molecular interactions and H2O diffusion in a poly(lactic-acid)/graphene composite: A vibrational spectroscopy study

A composite system made of poly(l-lactic acid) (PLLA) and graphene nanoplatelets (GNP) was investigated by Raman and FTIR spectroscopy. Two compositions were prepared and characterized in comparison to the pristine polymer: they contained, respectively, 0.25 and 0.75 wt% of the nanofiller. The study was focused on the morphological properties of the system, and, in particular, on the level of dispersion and the homogeneity obtainable with the adopted preparation protocol. Furthermore, the possible molecular interactions taking place between the nanofiller and the polymer matrix were considered. Both the above issues were investigated by confocal Raman spectroscopy, with the aid of first-principle calculations to strengthen the spectral interpretation. Finally, the effect of the nanofiller on water diffusion was investigated by time-resolved FTIR spectroscopy, which provided accurate equilibrium and kinetic data, as well as molecular level information on the penetrant-to-substrate interactions. It was found that, for a 0.25 wt% composition, the adopted preparation protocol allowed us to achieve a dispersion at the level of single nanoplatelets, while for a 0.75 wt% composition, the GNP's aggregate into a co-continuous phase. PLLA/GNP interactions were detected by Raman spectroscopy, producing a detectable perturbation of the PLLA conformational equilibrium. Both the diffusivities and the equilibrium water uptake were found to decrease significantly by increasing the filler content.

A within-sibling pair analysis of lifestyle behaviours and BMI z-score in the multi-centre I.Family study

BACKGROUND AND AIMS

By investigating differences in lifestyle behaviours and BMI in sibling pairs, family-level confounding is minimized and causal inference is improved, compared to cross-sectional studies of unrelated children. Thus, we aimed to investigate within-sibling pair differences in different lifestyle behaviours and differences in BMI z-scores in children and adolescents.

METHODS AND RESULTS

We examined three groups of sibling pairs 1) all same-sex sibling pairs with maximum 4 years age difference (n = 1209 pairs from 1072 families in 8 countries, mean age 10.7 years, standard deviation 2.4 years), 2) sibling pairs discordant for overweight (n = 262) and 3) twin pairs (n = 85). Usual dietary intake was estimated by 24-h recalls and time spent in light (LPA) and moderate-to-vigorous physical activity (MVPA) was measured by accelerometers. Screen time, sleep and dieting for weight loss were assessed by questionnaires. Within all 3 groups of sibling pairs, more time in MVPA was associated with lower BMI z-score. Higher energy intake was associated with higher BMI z-score within twin pairs and within all sibling pairs who were not currently dieting for weight loss. Regarding LPA, screen time or sleep duration, no or inconsistent associations were observed for the three groups of sibling pairs.

CONCLUSIONS

MVPA and energy intake were associated with BMI differences within sibling and twin pairs growing up in the same home, thus independent of family-level confounding factors. Future studies should explore whether genetic variants regulating appetite or energy expenditure behaviours account for weight differences in sibling pairs.

Dietary calcium intake and adiposity in children and adolescents: Cross-sectional and longitudinal results from IDEFICS/I.Family cohort

BACKGROUND AND AIMS

Studies in children and adolescents suggest that higher dairy consumption may exert a protective effect on adiposity. However, only few studies examined the association between dietary calcium intake and body mass measures with conflicting results. We evaluated the association between total dietary calcium, calcium from dairy and non-dairy sources and anthropometric indices in a large European cohort of children and adolescents.

METHODS AND RESULTS

As many as 6,696 children belonging to the IDEFICS study were eligible for the cross-sectional analysis (Boys = 51%; age 6.0 ± 1.8 years; mean ± SD). Of these, 2,744 were re-examined six years later (Boys = 49.6%; age = 11.7 ± 1.8 years) in the framework of the I.Family study. The exposures were the baseline energy-adjusted total, dairy and non-dairy calcium intakes measured by a validated 24-h dietary recall. Multivariable linear regression was used to determine the association between calcium intake and z-scores of anthropometric indices (body mass index, BMI; waist circumference, WC; sum of skinfolds, SS; fat mass index, FMI) at baseline, and their variation over the 6 years follow-up. The association of dietary calcium with the incidence of overweight/obesity was also assessed. At baseline, an inverse association between total calcium intake and all the adiposity indices was consistently observed in boys, while only SS and FMI were significant in girls. The prevalence of overweight/obesity decreased significantly (P < 0.0001) across tertiles of calcium intake, in both sexes. Over the follow-up, boys with higher baseline calcium intake value showed significantly lower increase in BMI, WC and FMI z-scores, while in girls only a lower increase in WC z-score was observed. Only in boys, the risk to become overweight/obese decreased significantly across tertiles of calcium intake. Similar results were observed by analyzing only dietary calcium from dairy, while no association was observed between non-dairy calcium and adiposity indices.

CONCLUSIONS

We showed in a large cohort of European children and adolescents that dietary calcium intake may play a role in the modulation of body fat in developmental age. The association between dietary calcium and adiposity indices was driven by dairy calcium, while no effect was observed for non-dairy calcium intake. The existence of a sex-related difference in the association deserves further investigations.

Dietary sources of free sugars in the diet of European children: the IDEFICS Study

OBJECTIVE

To report dietary free sugars consumption and their different types and food sources in European children.

METHODS

The present study is based on the IDEFICS study, a European multicenter cohort study in children (2-9 years old) from eight countries, comprising 8308 children (51.4% males). Dietary intake of the previous 24 h was assessed using a computer-assisted 24-h dietary recalls (24-HDR) and the different types of sugars were assessed using the German food composition database.

RESULTS

Mean total energy intake was 1720 (SD 477) kcal/d for boys and 1631 (SD 451) kcal/d for girls. Total sugars intake was 98 (SD 52) g/day for boys and 93 (SD 49) g/day for girls. Free sugars intake was 81 (SD 49) g/day for boys and 77 (SD 47) g/day for girls. Girls had significantly lower intakes of energy, total and free sugars compared with than boys but did not differ in terms of percent of energy from total (23%) or free sugars (18%). There were large variations between countries in average % energy from free sugars (ranging from 13% in Italy to 27% in Germany). Less than 20% of children were within the recommended intake of 10% of energy from free sugars. The food groups that contributed substantially to free sugars intakes were "Fruit juices", "Soft drinks", "Dairy" and "Sweets and candies".

CONCLUSIONS

The contribution of free sugars to total energy intake in European children is higher than recommendations. The main food contributors to free sugars intake are sweetened beverages ("Fruit juices" and "Soft drinks"). It is especially important to reduce children's intake of free sugars, focusing in target population on certain foods and food groups.

TP53 Codon 72 Polymorphism does not Affect Risk of Cervical Cancer in Patients from the Gambia

Aims

A case-control study was performed to investigate the relationship between cervical cancer and TP53 polymorphism at codon 72 in young black African women from The Gambia.

Materials and Methods

The TP53 polymorphism at codon 72 was examined by PCR amplification and SSCP analysis in 40 patients with primary cervical cancer and in 20 healthy women of the same age and from the same geographical area. The occurrence of TP53 polymorphism in combination with the HPV-16 E6 genotype (assayed by PCR) was evaluated.

Results

The distribution of TP53 genotypes in cervical cancer patients and in the control group was not statistically different (p=0.45) and homozygosity for argine at residue 72 was not associated with cervical cancer (odds ratio: 1.24; 95% confidence interval 0.21-9.16). Similarly, a different genotype distribution, cervical cancer and presence of HPV-16 E6 were not observed.

Conclusions

These results cannot rule out an association between TP53 polymorphism at codon 72, HPV infection and the etiology of cervical cancer in this population sample.