Blockchain-Based Security Mechanisms for IoMT Edge Networks in IoMT-Based Healthcare Monitoring Systems.

Despite the significant benefits that the rise of Internet of Medical Things (IoMT) can bring into citizens' quality of life by enabling IoMT-based healthcare monitoring systems, there is an urgent need for novel security mechanisms to address the pressing security challenges of IoMT edge networks in an effective and efficient manner before they gain the trust of all involved stakeholders and reach their full potential in the market of next generation IoMT-based healthcare monitoring systems. In this context, blockchain technology has been foreseen by the industry and research community as a disruptive technology that can be integrated into novel security solutions for IoMT edge networks, as it can play a significant role in securing IoMT devices and resisting unauthorized access during data transmission (i.e., tamper-proof transmission of medical data). However, despite the fact that several blockchain-based security mechanisms have already been proposed in the literature for different types of IoT edge networks, there is a lack of blockchain-based security mechanisms for IoMT edge networks, and thus more effort is required to be put on the design and development of security mechanisms relying on blockchain technology for such networks. Towards this direction, the first step is the comprehensive understanding of the following two types of blockchain-based security mechanisms: (a) the very few existing ones specifically designed for IoMT edge networks, and (b) those designed for other types of IoT networks but could be possibly adopted in IoMT edge networks due to similar capabilities and technical characteristics. Therefore, in this paper, we review the state-of-the-art of the above two types of blockchain-based security mechanisms in order to provide a foundation for organizing research efforts towards the design and development of reliable blockchain-based countermeasures, addressing the pressing security challenges of IoMT edge networks in an effective and efficient manner.

Generating Datasets for Anomaly-Based Intrusion Detection Systems in IoT and Industrial IoT Networks.

Over the past few years, we have witnessed the emergence of Internet of Things (IoT) and Industrial IoT networks that bring significant benefits to citizens, society, and industry. However, their heterogeneous and resource-constrained nature makes them vulnerable to a wide range of threats. Therefore, there is an urgent need for novel security mechanisms such as accurate and efficient anomaly-based intrusion detection systems (AIDSs) to be developed before these networks reach their full potential. Nevertheless, there is a lack of up-to-date, representative, and well-structured IoT/IIoT-specific datasets which are publicly available and constitute benchmark datasets for training and evaluating machine learning models used in AIDSs for IoT/IIoT networks. Contribution to filling this research gap is the main target of our recent research work and thus, we focus on the generation of new labelled IoT/IIoT-specific datasets by utilising the Cooja simulator. To the best of our knowledge, this is the first time that the Cooja simulator is used, in a systematic way, to generate comprehensive IoT/IIoT datasets. In this paper, we present the approach that we followed to generate an initial set of benign and malicious IoT/IIoT datasets. The generated IIoT-specific information was captured from the Contiki plugin "powertrace" and the Cooja tool "Radio messages".

Short communication: Effect of bactofugation of raw milk on counts and microbial diversity of psychrotrophs.

Bactofugation is a centrifugal process for removing spores of microorganisms from milk, especially when it is destined for cheese making. Other microorganisms may be removed in bactofugation. This study aimed to verify the effect of milk bactofugation on the counts and microbial diversity of psychrotrophs. The raw milk was preheated (≈55°C) before being bactofuged, and samples were collected from 3 batches of milk: refrigerated raw, preheated, and bactofuged, representing the immediate conditions before and after bactofugation. The mean psychrotrophic counts of the 3 batches were 3.08 (±1.69) × 106, 193 (±232), and 20 (±26) cfu/mL, respectively. Preheating was sufficient to eliminate 99.99% of the raw milk psychrotrophs, but bactofugation further reduced 89.66% of psychrotrophs from preheated milk. Lysinibacillus fusiformis was the most frequently isolated species (45.7%) among the psychrotrophs of raw milk and, proportionally, were more frequent in preheated (37.5%) and bactofuged (60%) milk. Bacillus invictae (20%), Enterococcus faecalis (10%), and Kurthia gibsonii (10%) were also isolated from bactofuged milk. Albeit in small numbers, psychrotrophic, thermoduric, and spore-forming bacteria with known proteolytic and lipolytic activity remained in the milk after bactofugation, which apparently had no effect on a specific population of microorganisms but proportionally reduced the entire psychrotrophic microbiota of raw milk.

Quality of life and physical activity levels in outpatients with schizophrenia.

OBJECTIVES: To assess quality of life (QoL) and physical activity (PA) levels of outpatients with schizophrenia and healthy controls matched for age, gender, body mass index (BMI), hip circumference, waist circumference, and waist-to-hip ratio. Additionally, the present study investigated associations between PA levels, QoL, and anthropometric and behavioral measures among outpatients with schizophrenia. METHODS: Thirty-two outpatients with schizophrenia and 32 individuals without mental illness were included in the study. QoL and PA levels were assessed by the World Health Organization Quality of Life Instrument - Abbreviated version (WHOQOL-Bref) and by GT3X triaxial accelerometers, respectively. RESULTS: Outpatients with schizophrenia had poorer QoL and lower vigorous PA levels compared with healthy controls (p < 0.05). The group with schizophrenia showed a significant association between higher weight and lower scores in the mental health domain of the WHOQOL-Bref. A higher BMI was also significantly associated with lower scores in the physical health domain of the WHOQOL-Bref. Schizophrenic patients with smoking behaviors were associated with fewer steps per day and with less moderate to vigorous PA. CONCLUSIONS: This study seeks to shed some light upon the lifestyle of patients with schizophrenia. New psychosocial approaches should focus on PA, weight, and smoking management, thereby helping these patients to improve their QoL.

Association and comparison between visual inspection and bitewing radiography for the detection of recurrent dental caries under restorations.

PURPOSE: The aim of the present study was to investigate, in posterior teeth, the association between the characteristics of the margins of a restoration visually inspected and the presence, under restorations, of recurrent or residual dental caries detected by radiographic examination. Furthermore, the agreement between visual inspection and radiographs to detect dental caries was assessed. METHODS: Eighty-five permanent molars and premolars with resin restorations on the interproximal and/or occlusal faces, from 18 patients, were submitted for visual inspection and radiographic examination. The visual inspection involved the criteria of the International Caries Detection and Assessment System (ICDAS). Bitewing radiographs were used for the radiographic examination. Logistic regression was used to analyse the association between the characteristics of the margins of a restoration assessed by visual inspection (absence of dental caries, or early, established, inactive and active lesions) and the presence of recurrent caries detected by radiographs. Kappa coefficients were calculated for determining agreement between the two methods. RESULTS: The Kappa coefficient for agreement between visual inspection and radiographic examination was 0.19. Established lesions [odds ratio (OR) = 9.89; 95% confidence interval (95% CI): 2.94-33.25; P < 0.05] and lesion activity (OR = 2.57; 95% CI: 0.91-7.27; P < 0.05) detected by visual inspection, were associated with recurrent or residual dental caries detected by radiographs. Restorations with established and active lesions at the margins had a greater chance of exhibiting recurrent or residual lesions in the radiographic examination. CLINICAL SIGNIFICANCE: The present findings demonstrate that restorations with established and active lesions at the margins when visually inspected often require removal and retreatment.

The influence of temporary cements on dental adhesive systems for luting cementation.

OBJECTIVE: This study tested the hypothesis that bond strength of total- and self-etching adhesive systems to dentine is not affected by the presence of remnants from either eugenol-containing (EC) or eugenol-free (EF) temporary cements after standardized cleaning procedures. METHODS: Thirty non-carious human third molars were polished flat to expose dentine surfaces. Provisional acrylic plates were fabricated and cemented either with EC, EF or no temporary cements. All specimens were incubated for 7 days in water at 37°C. The restorations were then taken out and the remnants of temporary cements were mechanically removed with a dental instrument. The dentine surfaces were cleaned with pumice and treated with either total-etching (TE) or self-etching (SE) dental adhesive systems. Atomic force microscopy was used to examine the presence of remnants of temporary cements before and after dentine cleaning procedures. Composite resin build-ups were fabricated and cemented to the bonded dentine surfaces with a resin luting cement. The specimens were then sectioned to obtain 0.9mm(2) beams for microtensile bond strength testing. Fractographic analysis was performed by optical and scanning electron microscopy. RESULTS: ANOVA showed lower mean microtensile bond strength in groups of specimens treated with EC temporary cement than in groups treated with either no cement or an EF cement (p<0.05). Mean microtensile bond strength was lower in groups employing the SE rather than the TE adhesive system (p<0.001). SE samples were also more likely to fail during initial processing of the samples. There was no evidence of interaction between cement and adhesive system effects on tensile strength. Fractographic analysis indicated different primary failure modes for SE and TE bonding systems, at the dentine-adhesive interface and at the resin cement-resin composite interface, respectively. CONCLUSION: The use of eugenol-containing temporary cements prior to indirect bonding restorations reduce, to a statistically similar extent, the bond strength of both total- and self-etching adhesive systems to dentine.

Influence of muscle fitness test performance on metabolic risk factors among adolescent girls.

BACKGROUND: The purpose of this study was to examine the association between muscular fitness (MF), assessed by 2 components of Fitnessgram test battery, the Curl-Up and Push-Ups tests and the metabolic risk score among adolescent girls. METHODS: A total of 229 girls (aged 12-15 years old) comprised the sample of this study. Anthropometric data (height, body mass, waist circumference) were collected. Body mass index (BMI) was also calculated. Muscular strength was assessed taking into account the tests that comprised the FITNESSGRAM test battery, i.e. the curl-up and the push-up. Participants were then categorized in one of 3 categories according the number of tests in which they accomplished the scores that allow them to be classified in health or above health zone. The blood pressure [BP], fasting total cholesterol [TC], low density lipoprotein-cholesterol [LDL-C], high density lipoprotein-cholesterol [HDL-C], triglycerides [TG], glucose, and a metabolic risk score (MRS) were also examined. Physical Activity Index (PAI) was obtained by questionnaire. RESULTS: Higher compliance with health-zone criteria (good in the 2 tests), adjusted for age and maturation, were positive and significantly (p

Semi-invasive aspergillosis in an immunocompetent patient with Swyer-James-MacLeod Syndrome: a case report.

INTRODUCTION: Invasive and semi-invasive pulmonary aspergillosis usually occurs in immunocompromised patients. It has been described occasionally in patients with normal immunity and previous lung disease such as chronic obstructive pulmonary disease.Swyer-James-MacLeod Syndrome is a rare condition characterized by hyperlucency of one lung, lobe or part of a lobe due to decreased vascularity and air trapping. CASE PRESENTATION: We report a case of semi-invasive pulmonary aspergillosis in a 38-year-old Portuguese, Caucasian man who is immunocompetent, with a pre-existing Swyer-James-McLeod Syndrome, a structural lung disease. CONCLUSIONS: To the best of our knowledge, this is the first reported case in the literature on the relationship between these two diseases. Although rare, aspergillosis can occur in immunocompetent adults with a pre-existing lung disease other than chronic obstructive pulmonary disorder.

Criterion-related validity of the 20-m shuttle run test in youths aged 13-19 years.

We assessed the agreement between maximal oxygen consumption (VO2max) measured directly when performing the 20-m shuttle run test and estimated VO2max from five different equations (i.e., Barnett, equations a and b; Leger; Matsuzaka; and Ruiz) in youths. The 20-m shuttle run test was performed by 26 girls (mean age 14.6 years, s = 1.5; body mass 57.2 kg, s = 8.9; height 1.60 m, s = 0.06) and 22 boys (age 15.0 years, s = 1.6; body mass 63.5 kg, s = 11.5; height 1.70 m, s = 0.01). The participants wore a portable gas analyser (K4b2, Cosmed) to measure VO2max during the test. All the equations significantly underestimated directly measured VO2max, except Barnett's (b) equation. The mean difference ranged from 1.3 ml x kg(-1) x min(-1) (Barnett (b)) to 5.5 ml x kg(-1) x min(-1) (Leger). The standard error of the estimate ranged from 5.3 ml x kg(-1) x min(-1) (Ruiz) to 6.5 ml x kg(-1) x min(-1) (Leger), and the percentage error ranged from 21.2% (Ruiz) to 38.3% (Léger). The accuracy of the equations available to estimate VO2max from the 20-m shuttle run test is questionable at the individual level. Furthermore, special attention should be paid when comparisons are made between studies (e.g., population-based studies) using different equations. The results of the present study suggest that Barnett's (b) equation provides the closest agreement with directly measured VO2max (cardiorespiratory fitness) in youth.

Microtensile bond strength of resin-based composites to Ti-6Al-4V.

OBJECTIVE: The purpose of this study was to determine the microtensile bond strength of various resin composite/adhesive systems to alumina particle abraded Ti-6Al-4V substrate after aging for 24h, 10 days, and 30 days in distilled water at 37 degrees C. METHODS: Four laboratory resin composite veneering systems (Gradia, GR; Solidex, SOL; Ceramage, CER; and Sinfony, SF) were bonded to 25 mm diameter machined disks of Ti-6Al-4V with their respective adhesive and methodology, according to the manufacturer's instructions. Microtensile bars of approximate dimensions 1 mm x 1 mm x 6 mm were prepared for each resin composite/adhesive system. After cutting, groups (n=12) from each adhesive system were separated and either stored in water at 37 degrees C for 24h (baseline) or aged for 10 or 30 days prior to loading to failure under tension at a cross head speed of 1.0mm/min. Failure modes were determined by means of scanning electron microscopy (SEM). Statistical analysis was performed through one-way ANOVA and Tukey's test at 95% level of significance. RESULTS: Significant variation in microtensile bond strength was observed for the different systems and aging times. SOL and GR showed the highest mean bond strength values followed by SF and CER at baseline. Aging specimens in water had an adverse effect on bond strength for SOL and CER but not for the SF and GR groups. SIGNIFICANCE: In vitro bond strength of laboratory resin composites to Ti-6Al-4V suggests that strong bonds can be achieved and are stable for certain systems, making them useful as an alternative for esthetic fixed prosthetic restorations.

Differences in school-day patterns of daily physical activity in girls according to level of physical activity.

BACKGROUND: The purpose of this study was to examine whether there are differences in physical activity (PA) during specific periods of the day among active and less-active girls. METHODS: The sample comprised 54 girls age 10 to 15 years. PA was assessed by accelerometry. Girls were grouped as less active, active, and highly active. RESULTS: Total minutes of moderate-to-vigorous physical activity (MVPA) was significantly higher in more-active girls than in their less-active peers (113 and 72 min/d, respectively). The most-active groups were significantly more engaged in MVPA during the outside-of-school period than were less-active girls. Highly active girls spent a significantly higher amount of their MVPA time outside of school than did the less-active group, which spent a significantly higher proportion of MVPA time during late afternoon. CONCLUSION: Outside-of-school PA is a key point for MVPA engagement. Particularly for the less-active girls, however, schools might provide additional PA.

Daily differences in patterns of physical activity among overweight/obese children engaged in a physical activity program.

The aim of this study was to compare the physical activity of overweight/obese children during days when they attended a physical activity program, and days when they did not. This is a cross-sectional intervention study of daily physical activity. The participants were referred by family, doctors, or hospital pediatricians to take part in a 10-month interdisciplinary, outpatient obesity intervention program for children. The subjects included 41 overweight and obese children aged 8-16 years, 19 boys (46%) and 22 girls (54%); BMI: 25.7 + 3.3 kg m(-2). The MTI Actigraph was used as an objective measure of daily physical activity over seven consecutive days. Physical activity program days presented a significantly higher percentage of time (4.68%) spent in moderate-to-vigorous activity compared with no physical activity program days (3.16%) and weekend (2.7%). The results of this study suggest that a physical activity program can help increasing daily physical activity in obese children, with a special focus on MVPA level. Our data point that obese children are less active at weekend than during weekdays.

Relationship of single measures of cardiorespiratory fitness and obesity in young schoolchildren.

The purpose of this study was to examine differences of cardiorespiratory fitness (CRF) among weight groups, and the associations of CRF with obesity (body mass index) in a sample of young children. Anthropometric data (height, body mass, and two skinfolds) were collected for 255 healthy children aged 8-10 years (127 boys and 128 girls). Children were placed in three groups (nonobese, overweight, and obese), using body mass index (BMI) sex- and age-specific cutoff points. Cardiorespiratory fitness was assessed with a 1-mile run test. Participants were separated into two groups: fit and unfit, according to age- and sex-specific scores defined by FITNESSGRAM. The prevalence of overweight (30.5% vs. 29.1%) and obesity (13.2% vs. 12.6%) was at the same magnitude for boys and girls. Overall, 109 children (42.7%) were overweight and obese. Sums of skinfolds, weight, and BMI were significantly lower (P < 0.05) in lean boys and girls compared to their overweight and obese counterparts. Regarding height, no significant differences were found in girls, while in boys, significant differences were only found between nonobese and obese. No differences were found in obesity groups according to CRF in boys, while significant differences were found for girls (P < 0.01). Logistic regression analysis showed that girls who were overweight (odds ratio = 0.05, P = 0.000) or obese (odds ratio = 0.09, P = 0.001) were likely to be unfit. No significant results were found in boys. Overweight and obese children presented higher sums of skinfolds and weight compared with their lean counterparts. Increased BMI was significantly associated with lower CRF in girls. Thus, our data clearly showed potential gender differences of body composition in CRF, which would be of great clinical significance. Therefore, even at young ages, at least for girls, the beneficial impact of low BMI values on CRF is shown with important clinical and public health implications.

Physical activity and biological risk factors clustering in pediatric population.

BACKGROUND: From a preventive point of view, it is especially important to investigate the life style risk factors connected to cardiovascular disease (CVD) biological risk factors clustering. The purposes of this study were (I) to determine in pediatric population the coexistence of biological cardiovascular disease risk factors (high blood pressure (HBP), percentage of high fat mass (%HFM), and high total cholesterol (HTC)) and (II) to study the relationship between low physical activity, a lifestyle risk factor, with those biological risk factors. METHODS: This study comprised 1461 children (699 males and 762 females) aged between 8 and 15 years old. The following measurements were carried out: blood pressure, percentage of fat mass, total cholesterol (TC), and physical activity. The quartiles, adjusted for age and gender, were the criterion used to classify the subjects at risk. Odds ratios and confidence intervals at 95% were used to study HBP, HTC, and %HFM clustering in both genders. Multinomial logistic regression was used to investigate the relationship between clustering and physical activity index (PAI). RESULTS: The findings of this study indicated that there is clustering for the biological risk factors, specially between HBP and %HFM for females. It can be observed that about half of the subjects had at least one biological risk factor. CONCLUSIONS: The results of the present study suggest that children and adolescents with higher PAI have a lower number of biological risk factors for CVD.

Patterns of daily physical activity during school days in children and adolescents.

The purpose of this study was to examine the weekday patterns of moderate-to-vigorous physical activity (MVPA) in school children and adolescents and determine if there are periods of the day that are representative of their typical MVPA. The sample comprised 84 subjects (boys, n = 30; girls, n = 54), age 8-15 years old. Daily totals for the physical activity variables were calculated by summing the values from 13 hr of physical activity (PA) measurements (9:00-22:00), with 60-min time blocks comprising each day. The MVPA data values were categorized in four daily periods: morning (9:00-11:59), noon (12:00-14:59), late afternoon (15:00-17.59), and evening (18:00-21.59). Our data show that boys participated significantly more in MVPA than girls. Despite no clear patterns or differences among sex being found, girls showed higher percent of time engaged in MVPA during the morning and early afternoon periods (sum of two periods 51.0%), while boys' percent of time engaged in MVPA is higher at late afternoon and evening periods (sum of two periods 53.8%). The principal components analyses showed four distinct components that accounted for 67% of the variance, as follows: school hours (component 1); lunchtime and outside-school activities (component 2); morning time before school period (component 4); and period before bedtime (component 3) appear as distinct periods of the day. In conclusion, the present study shows that boys engaged more in MVPA than girls. Girls tend to be more active during school periods, while boys are more active after school.

Association of maturation, sex, and body fat in cardiorespiratory fitness.

The aims of this cross-sectional study were 1) to estimate changes in body composition and cardiorespiratory fitness across stages of pubertal maturation, and 2) to describe the relationship between maturity status and body fatness, regional fat distribution, and cardiorespiratory fitness. The sample consisted of 494 children (254 males, 240 females), 8-16 years of age. Height and weight were measured with standard anthropometric methods. Percentage of fat (%F) was estimated from two skinfold thicknesses and regional fat distribution was estimated by the ratio of the subscapular to the triceps skinfold (S/T ratio). Biological maturity was based on self-assessment of breast stages in females and pubic hair stages in males. A maximal multistage 20-m shuttle run was used to predict maximal aerobic capacity from maximal aerobic speed. Both VO(2)max and 20SRT-time were used as indicators of cardiorespiratory fitness. ANCOVA with age as the covariate was used. There were significant differences among girls across pubertal stages. Among boys, only weight and height differed significantly by stage of maturity. When adjusted for maturity status, cardiorespiratory fitness expressed either as VO(2)/kg body mass or 20SRT-time was inversely associated with %F in both sexes. This suggests that sexual maturity status alone accounts for a small portion of the variance in aerobic fitness. Height, %F and the S/T ratio were also significantly associated with VO(2)/kg body mass and 20SRT-time.