Associations of COVID-19 lockdown restrictions with longer-term activity levels of working adults with type 2 diabetes (Preprint)

BACKGROUND Lockdown restrictions reduce COVID-19 community transmission; however, they may pose challenges for non-communicable disease management. A 112-day hard lockdown in Victoria, Australia (commencing March 23, 2020), which affected an intervention trial of reducing and breaking up sitting time in desk workers with type 2 diabetes who were using a provided consumer grade activity tracker (Fitbit). OBJECTIVE To compare continuously recorded activity levels preceding and during COVID-19 lockdown restrictions among working adults with type 2 diabetes participating in a sitting less and moving more intervention. METHODS Eleven participants (8/11 male; mean [SD] age 52.8 [5.0] years) in Melbourne, Australia had Fitbit activity tracked before (mean [SD]: 122.7 [47.9] days) and during (99.7 [62.5] days) city-wide COVID-19 lockdown restrictions. Regression models compared device (Fitbit Inspire HR)-derived activity (steps; METs [metabolic equivalents], mean time in sedentary, lightly, fairly, and very active minutes, and usual bout durations) during restrictions, to pre-restriction. Relative rates (RR) <1.00 indicated a decline in activity levels following restrictions. RESULTS Total wear days were 2447. There was a decrease in steps (-1,584 steps; RR: 0.91; 95%CI: 0.89, 0.93), METs (-83 METs; RR: 0.95; 95%CI: 0.94, 0.95), lightly active (RR: 0.96; 95%CI: 0.92, 0.99), fairly active (RR: 0.82; 95%CI: 0.79, 0.85), very active (RR: 0.92; 95%CI: 0.89, 0.95) intensity minutes, and increases in sedentary minutes (RR: 1.03; 95%CI: 1.01, 1.06). Only very active (+5.1mins) and sedentary (+4.3mins) bout durations changed significantly. CONCLUSIONS In adults with type 2 diabetes, COVID-19 lockdown restrictions were associated with decreases in overall activity levels and increases in very active and sedentary bout durations. A Fitbit monitor provided meaningful continuous long term data in this context. CLINICALTRIAL Australian New Zealand Clinical Trials Registry ANZCTRN12618001159246

Different wear in two highly cross-linked polyethylene liners in THA: wear analysis with EBRA

Introduction The purpose of this study was (1) to compare early wear rates in bedding-in periods of two highly cross-linked polyethylene liners frequently used in THA and (2) to evaluate risk factors indicating a possible higher wear rate. Materials and methods 1120 patients who received a Crossfire or a Marathon highly cross-linked (HXLPE) ultra-high-molecular-weight polyethylene liner in primary THA at our Department between 2004 and 2018 were retrospectively reviewed. Patients with (1) only alumina heads on HXLPE acetabular bearings, (2) a minimum of four radiographs per patient for EBRA analysis, (3) no osteolysis around the acetabular cup and (4) no dislocations that occurred during the study period were included. Results A total of 328 patients (female: 183; male: 145; Marathon: 179; Crossfire: 149) fulfilled the inclusion criteria. Mean follow-up was 24 (range 7–51) months. With 0.22 (SD 0.27) mm mean total wear for the Marathon was three times greater than for the Crossfire, namely 0.07 (SD 0.14) mm. Mean cup migration during the investigated follow-up period was 0.7 (SD 0.8) mm for the Pinnacle and 0.5 mm (SD 0.7) for the Trident PSL cups. Conclusion Initial early wear of highly cross-linked polyethylene in combination with alumina heads differs strongly between products. Long-term survivorship of these liners should be observed to determine whether early wear has an impact on aseptic loosening. Level of evidence Level III (retrospective comparative study with prospective cohort).

Constitutive Modeling for Prediction of Optimal Process Parameters in Tribo-corrosion Inhibition of Steel Pipes Carrying Fracking Fluid

The present work examines the effect of three propriety corrosion inhibitors (Dynarate, DWP and CalGuard) on the tribo-corrosion behavior of AISI 4715 steels used to carry fracking liquid from their storage pool to the geological formation. The effect of these three additives on the wear and corrosion behavior of AISI 4715 steel was investigated using a reciprocating tribometer integrated with an open circuit potential electrochemical apparatus. Response Surface Methodology (RSM) was applied to statistically model the effects of various concentrations of Dynarate, DWP andCalGuard on the average coefficient of friction (COF) between the steel and a sapphire counter surface, as well as the total wear loss of the steel due to the combined action of wear-corrosion and inhibition efficiency during sliding. The mathematical regression models were derived from the analysis of variance (ANOVA) techniques. Optimization of the individual variables to minimize the friction and wear responses was estimated using RSM. A full quadratic regression model was established and authenticated before the variables were optimized for different responses. The overall results revealed that Dynarate significantly decreased the COF (0.147) and wear rate (0.3 mm/year) with an inhibitionefficiency of 480% at a concentration of 1%. To investigate the effectiveness of the regression model at predictingthe wear rate, the samples were characterized using 3D optical prolometer and scanning probe microscopy to describe the effect of various additive on the surface morphology of steel. The surface topography measurementsindicated the worn regions for the samples where the Dynarate additive was used was smoother compared with those having the DWP and CalGuard additives. This observation was attributed to the formation of protective lm which limits the transfer of aggressive ions transfer to the steel surface and reduced the total wear loss due to wear and corrosion.

Children’s moderate-to-vigorous physical activity on weekdays versus weekend days: a multi-country analysis

Purpose The Structured Days Hypothesis (SDH) posits that children’s behaviors associated with obesity – such as physical activity – are more favorable on days that contain more ‘structure’ (i.e., a pre-planned, segmented, and adult-supervised environment) such as school weekdays, compared to days with less structure, such as weekend days. The purpose of this study was to compare children’s moderate-to-vigorous physical activity (MVPA) levels on weekdays versus weekend days using a large, multi-country, accelerometer-measured physical activity dataset. Methods Data were received from the International Children’s Accelerometer Database (ICAD) July 2019. The ICAD inclusion criteria for a valid day of wear, only non-intervention data (e.g., baseline intervention data), children with at least 1 weekday and 1 weekend day, and ICAD studies with data collected exclusively during school months, were included for analyses. Mixed effects models accounting for the nested nature of the data (i.e., days within children) assessed MVPA minutes per day (min/day MVPA) differences between weekdays and weekend days by region/country, adjusted for age, sex, and total wear time. Separate meta-analytical models explored differences by age and country/region for sex and child weight-status. Results/findings Valid data from 15 studies representing 5794 children (61% female, 10.7 ± 2.1 yrs., 24% with overweight/obesity) and 35,263 days of valid accelerometer data from 5 distinct countries/regions were used. Boys and girls accumulated 12.6 min/day (95% CI: 9.0, 16.2) and 9.4 min/day (95% CI: 7.2, 11.6) more MVPA on weekdays versus weekend days, respectively. Children from mainland Europe had the largest differences (17.1 min/day more MVPA on weekdays versus weekend days, 95% CI: 15.3, 19.0) compared to the other countries/regions. Children who were classified as overweight/obese or normal weight/underweight accumulated 9.5 min/day (95% CI: 6.9, 12.2) and 10.9 min/day (95% CI: 8.3, 13.5) of additional MVPA on weekdays versus weekend days, respectively. Conclusions Children from multiple countries/regions accumulated significantly more MVPA on weekdays versus weekend days during school months. This finding aligns with the SDH and warrants future intervention studies to prioritize less-structured days, such as weekend days, and to consider providing opportunities for all children to access additional opportunities to be active.

The concept of a cementless isoelastic monoblock cup made of highly cross-linked polyethylene infused with vitamin E: Radiological analyses of migration and wear using EBRA and clinical outcomes at mid-term follow-up

Background: The newest generation of cementless titanium-coated, isoelastic monoblock cup with vitamin E-blended highly cross-linked polyethylene (HXLPE) was introduced to the market in 2009. The aim of the present study was to obtain mid-term follow-up data including migration and wear analyses.Methods: This prospective study investigated 101 primary total hip arthroplasty (THA) cases in 96 patients treated at a single institution. Patients were allowed full weight-bearing on the first day postoperatively. Harris hip score (HHS) and pain and satisfication on a visual analogue scale (VAS) were assessed at a mean follow-up of 79.0 months. Migration and wear were assessed using Einzel-Bild-Roentgen-Analyse (EBRA) software. Radiological acetabular bone alterations and complications were documented.Results: At mid-term follow-up (mean 79.0 months, range: 51.8–101.7), 81 cases with complete clinical and radiological data were analyzed. Utilisable EBRA measurements were obtained for 42 hips. The mean HHS was 91.1 (range 38.0–100.0), VAS satisfaction was 9.6 (range 6.0–10.0), VAS rest pain was 0.2 (range 0.0–4.0), and VAS load pain was 0.6 (range 0.0–9.0). Mean migration was 0.86 mm (range: 0.0–2.56) at 24 months and 1.34 mm (range: 0.09–3.14) at 5 years, and the mean annual migration rate was 0.22 (range: -0.24–1.34). The mean total wear was 0.4 mm (range: 0.03–1.0), corresponding to a mean annual wear rate of 0.06 mm per year (range: 0.0–0.17). Radiographic analysis did not reveal any cases of osteolysis, and no revision surgeries had to be performed.Conclusions: After using vitamin-E blended HXLPE in cementless isoelastic monoblock cups, there were no obvious signs of osteolysis or aseptic loosening occurred. No patients required revision surgery after mid-term follow-up. Cup migration and wear values were well below the benchmarks considered predictive for potential future failure.

Comparison of 24 h ECG Holter Monitoring with Real-time Long-term ECG Monitoring System using ECGalert Software and Savvy Single-Lead Patch

AIM: The aim of the study was to show non-inferiority of the single-channel ECGalert system to the gold standard (ECG Holter) in the detection of arrhythmias over the total wear time of both devices. METHODS: A prospective study enrolled a total of 165 patients hospitalized at the University Clinic of Cardiology, who underwent simultaneous single-channel ECG recording with ECGAlert system and a conventional 24 h Holter monitor on the 1st day and continued ECGAlert monitoring for few more days, under assignment of the doctor or at the wish of the patient. RESULTS: A total of 165 patients were included in the study, 61.2% male, mean age of 58.4 ± 12.7 years. Mean duration of ECG Holter monitoring was 23.2 ± 0.5 h and mean duration of ECGalert/Savvy monitoring was 64.6 ± 31.2. During the first 24 h of simultaneous ECG monitoring with both methods, no statistically significant difference was found in arrhythmia detection. Over the total wear time of both devices, the ECGalert system detected significantly more AF episodes as compared to Holter (p < 0.000). ECGalert demonstrated significantly lower detection rate of false pauses (0.001). However, false detection of episodes of VT or AF was significantly higher in ECGalert system versus Holter (p < 0.000 and p < 0.000 respectively). Patients were more satisfied with ECGalert system, due to lesser interference in daily activities. CONCLUSION: The ECGalert system demonstrated superiority over traditional Holter monitoring in arrhythmia detection in the total monitoring period, but not in the first 24 h.

IMPROVING OF FRETTING RESISTANCE INTERMETALLIC Ti2AlNb ALLOY

The results of research on improving the fretting resistance of a titanium alloy made of orthorhombic titanium aluminide Ti2AlNb by forming a coating consisting of a barrier and an outer layer on the surface using an industrial vacuum-arc installation MAP-3 are presented. The dependences of the total wear and the coefficient of friction of samples made of Ti2AlNb alloy with and without coating in combination with a counterbody made of high-strength welded dispersed-hardening alloy during fretting damage tests at room (20 °C) and elevated (700 °C) temperatures are established. The kinetics of oxygen saturation of the surface of samples made of Ti2AlNb alloy with and without coating at the operating temperature of the alloy based on 200 h is shown. The phase and elemental compositions of the fretting-resistant coating after high-temperature exposure are investigated.

Cardiac Ambulatory Monitoring: New Wireless Device Validated Against Conventional Holter Monitoring in a Case Series

Background: Cardiac arrhythmias are very common but underdiagnosed due to their transient and asymptomatic nature. An optimization of arrhythmia detection would permit to better treat patients and could substantially reduce morbidity and mortality. The SmartCardia ScaAI wireless patch is a novel CE IIa approved, single-lead electrocardiographic (ECG) ambulatory monitor designed for cardiac arrhythmias detection.Hypothesis: The accuracy of the new SmartCardia wireless patch to detect arrhythmias is comparable to the conventional Holter monitoring.Methods: Patients referred for a suspicion of arrhythmia between February and March 2020 were included in the trial. Simultaneous ambulatory ECG were recorded using a conventional 24-h Holter and the SmartCardia. The primary endpoint was the detection of cardiac arrhythmias over the total wear time of the devices, defined as premature atrial contraction (PAC), supraventricular tachycardia ≥3 beats, premature ventricular contraction (PVC), and ventricular tachycardia ≥3 beats. Conduction abnormalities, pause ≥2 s and atrioventricular block (AVB), were also tracked. McNemar's test was used to compare the matched pairs of data from both devices.Results: A total of 40 patients were included in the trial. Over the total wear time, there was no significant difference between the devices for ventricular and supraventricular arrhythmias detection. Pauses and AVB were equally identified by the two devices in three patients.Conclusion: Over the total wear time, the SmartCardia device showed an accuracy to detect arrhythmia similar to the 24-h Holter monitoring: single-lead, adhesive-patch monitoring might become an interesting alternative to the conventional Holter monitoring.

The concept of a cementless isoelastic monoblock cup made of highly cross-linked polyethylene infused with vitamin E: Radiological analyses of migration and wear using EBRA and clinical outcomes at mid-term follow-up

BackgroundThe newest generation of cementless titanium coated, isoelastic monoblock cup with vitamin E-blended highly cross-linked polyethylene (HXLPE) has been introduced to the market in 2009. Aim of the present study was to obtain mid-term data including the analyses of migration and wear.MethodsThe present prospective study investigated 101 primary total hip arthroplasty (THA) cases in 96 patients at a single institution. Patients were allowed full weight-bearing on the first day postoperatively. Harris hip score (HHS) as well as pain and satisfication on visual analogue scale (VAS) were assessed during a mean follow-up of 79.0 months. Migration and wear were assessed using Einzel-Bild-Roentgen-Analyse (EBRA) software. Additionally, radiological alterations in the acetabular bone and complications were documented.ResultsAt mid-term follow-up (mean 79.0 months (range: 51.8 – 101.7)), 81 cases with complete clinical and radiological data were analyzed. In 42 hips utilisable EBRA measurements were obtained. HHS was 91.1 (range 38.0 – 100.0), satisfaction on VAS was 9.6 (range 6.0 – 10.0), rest pain on VAS was 0.2 (range 0.0 – 4.0), and load pain on VAS was 0.6 (range 0.0 – 9.0). Mean migration was 0.86 mm (range: 0.0 – 2.56) at 24 months and 1.34 mm (range: 0.09 – 3.14) at 5 years. Mean annual migration rate was 0.22 (range: -0.24 – 1.34). Mean total wear was 0.4 mm (range: 0.03 – 1.0). The mean annual wear rate was 0.06 mm per year (range: 0.0 – 0.17). Radiographic analysis showed osteolysis in none of the cases and no revision surgeries had to be performed.ConclusionUsing vitamin-E blended HXLPE in cementless isoelastic monoblock cups, no signs of osteolysis were obvious and no cases of aseptic loosening occurred. There was no need of revision surgery at mid-term. Values for cup migration and wear stay well below the benchmarks which are considered predictive for potential future failure.Trial registrationThe trial registration number on ClinicalTrial.gov: NCT04322916 (retrospectively registered at 26.03.2020).

Oxidation and Wear Mechanisms of FeCoCrNiMnAlx Cladding Layers at High-Temperature Condition

FeCoCrNiMnAlx high-entropy alloy (HEA) cladding layers were successfully fabricated on H13 steel by laser cladding. The microstructure and properties of the FeCoCrNiMnAlx HEA cladding layers were systematically studied. The influence of Al content on high-temperature wear resistance of HEAs was investigated by depth-of-field microscopy, XRD, SEM and EDS. Addition of Al element affected the mechanism of oxidation and strengthening of the cladding layers, and effectively promoted its anti-oxidant and abrasion resistance. Compared with the FeCoCrNiMn cladding layer, the FeCoCrNiMnAl0.75 cladding layer enhanced the anti-plastic deformation capacity by 7.1% and reduced oxidation weight gain and total wear weight loss at high temperature by 36.79% and 79.0%, respectively. The wear mechanisms of the cladding layer at high temperature were mainly oxidation wear and abrasive wear, while adhesive wear took a backseat.