Antibacterial and Photocatalytic Coatings Based on Cu-Doped ZnO Nanoparticles into Microcellulose Matrix

The paper presents a successful, simple method for the preparation and deposition of new hybrid Cu-doped ZnO/microcellulose coatings on textile fibers, directly from cellulose aqueous solution. The morphological, compositional, and structural properties of the obtained materials were investigated using different characterization methods, such as SEM-EDX, XRD, Raman and FTIR, as well as BET surface area measurements. The successful doping of ZnO NPs with Cu was confirmed by the EDX and Raman analysis. As a result of Cu doping, the hybrid NPs experienced a phase change from ZnO to (Zn_0.9Cu_0.1)O, as shown by the XRD results. All the hybrid NPs exhibited a high degree of crystallinity, as revealed by the very sharp reflections in XRD patterns and suggested also by the Raman results. The evaluation of the very low copper-doping (0.1-1 at.%) effect has shown different behavior trends of the hybrid coatings compared with the starting oxide NPs, for MB and MO photodegradation. Continuous increases up to 92% and 60% for MB and MO degradation, respectively, were obtained at maximum 1 at.%-Cu doping coatings. Strong antibacterial activity against S. aureus and E. coli were observed.

The role of segmental speckle tracking echocardiography in characterising right ventricle dilation patterns: a multicentre study on healthy adolescent athletes

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): UK Research and Innovation - Medical Research Council GW4 Studentship

Background

Right ventricle inflow (RV) dilation is a common adaptation to training in professional athletes, but how this impacts myocardial mechanics is yet unclear. Previous studies in athletes have found changes in segmental longitudinal strain (Sl), namely mid segment Sl, compared to normal controls, and have proposed RV dilation as a possible explanation. Whether different patterns of RV dilation are found in athletes, and if these influence regional RV mechanics is not known.

Purpose

To describe the patterns of RV dilation in healthy adolescent athletes and their relationship to segmental myocardial mechanics.

Methods

A total of 346 healthy athletes (<18 years) screened at 3 sports academies between 2014 and 2019 with measurements for RV Sl, RV basal and RV apical diameters were included. Four groups were defined based on the basal and apical RV diameters size relative to the whole group distribution: No RV dilation (both basal and apical RV diameter under the 25th percentile), basal dilation (only basal RV above the 75th percentile), apical dilation (only apical RV above the 75th percentile) and global dilation (both the basal and apical RV above the 75th percentile). The segmental Sl was compared between the groups using a one-way ANOVA test with Bonferroni correction.

Results

The mean (SD) age was 14.5 (1.6) years, with athletes coming from various ethnic (55% arab, 22% white and 22% black) and sports backgrounds (75% mixed, 11% power, 8% endurance and 6% skill). Based on the RV diameters, the following groups were defined: no dilation (n = 35), basal dilation (n = 53), apical dilation (n = 51) and global dilation (n = 33). There were variations in dilation pattern by ethnicity and practised sports (Figure 1).

RV free wall Sl was less negative ("lower") in the apical and global dilation groups compared to the no dilation group (-26.7% and -26.4% vs -28.6%, p = 0.04 and 0.03, respectively). Mid segment Sl was consistently lower in all 3 dilation pattern groups, compared to the no dilation group (Figure 2, *denotes p < 0.05). Basal Sl was lower in the global dilation group compared to those with no dilation (p = 0.05). There were also differences between the basal and apical dilation groups: basal Sl was lower (p = 0.01) and apical Sl higher (p = 0.02) the apical dilation group.

Conclusions

RV dilation in healthy athletes can be global, predominately basal or predominately apical. Apical and global dilation were more prevalent in non-white ethnicity, endurance and power sports. Lower mid segment Sl values were observed in all 3 dilation patterns, but FW Sl was only lower in the apical and global dilation groups. This suggests that there are different patterns of RV remodelling in athletes, which can be further characterised using segmental strain analysis. Abstract Figure. RV dilation by ethnicity and sport  Abstract Figure. RV segmental strain by RV dilation

Can left ventricular speckle tracking imaging be used in left ventricular non-compaction cardiomyopathy screening? A study of healthy paediatric athletes with and without echocardiographic criteria

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): The study was support by a contractual research partnership between the University of Bristol and Canon Medical Systems UK

Background

Left ventricular non-compaction (LVNC) is a rare cardiomyopathy, with hypertrabeculation often observed in athletes. In confirmed LVNC, LV systolic strain and rotational mechanics have been shown to be abnormal. Whether healthy athletes meeting echocardiographic LVNC criteria exhibit abnormal myocardial mechanics is not known.

Purpose

The aim of this study is to evaluate the prevalence of healthy paediatric athletes meeting the Jenni criteria for LVNC and how this relates to LV systolic function and rotational mechanics.

Methods

Professional athletes under 18 years undergoing comprehensive pre-participation screening (2014-2017) at two sports academies were included. Jenni criteria for LVNC were assessed from short axis LV views. Global and segmental peak systolic longitudinal (Sl) and circumferential strain (Sc), basal rotation (basal Rot) and apical rotation (apical Rot) were calculated using speckle tracking imaging.

Results

A total of 201 boys (11.9-18 years, median 15.1 years) were included, with diverse ethnicity (47.7% Arab, 28.5% Black, 21.8% White, and 2% other) and sports background (60% football, 21.2% athletics, 18.8% other).

Of these n = 16 (8%) met the Jenni criteria for LVNC and were more likely to be of Black ethnicity than Arab or White (12.7% vs 4.4% or 9.5%). There were no differences in global, lateral or septal Sl, basal, mid or apical Sc, basal Rot or apical Rot between participants with or without Jenni criteria for LVNC (Table 1).

Conclusions

In healthy paediatric athletes, those meeting the criteria for LVNC (8%) do not have abnormal longitudinal, circumferential strain and rotational mechanics, compared to those without LVNC criteria. This finding supports the use of speckle tracking echocardiography as a tool in differentiating pathological changes reported in LVNC from exercise associated adaptations observed in athletes during preparticipation screening.

LV mechanics Jenni criteria presence With Jenni criteria Median (IQR) Without Jenni criteria Median (IQR) p value Global LV Sl -18.6% (-19.1;-17.7) -18.6% (-19.7;-17.8) 0.7 Lateral Sl -18.3% (-18.8;-17.2) -18.5% (-19.8;-17.6) 0.5 Septal Sl -18.6% (-20.6;-17.3) -18.7% (-20.1;-17.7) 0.7 Basal LV Sc -23% (-24.6;-21.6) -23.3% (-25.7;-21.6) 0.7 Mid LV Sc -24.9% (-27.1;-23.2) -25.1% (-27.1;-22.5) 0.9 Apical LV Sc -27.8% (-32.3;-24.8) -26% (30.5;-22.4) 0.2 Basal Rot -4o (-4.7;-2.5) -3.8o (-5.3;-2.5) 0.9 Apical Rot 6.4o (5.2;7.1) 4.4 (2.9;7.1) 0.2

Can right ventricular speckle tracking imaging be used in arrhytmogenic cardiomyopathy screening? A study of healthy paediatric athletes with and without echocardiographic modified task force criteria

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): The study was support by a contractual research partnership between the University of Bristol and Canon Medical Systems UK.

Background

Arrhytmogenic cardiomyopathy (ACM) is a major cause of sudden cardiac death among young athletes. Screening these individuals can be challenging due to right ventricular (RV) exercise-related remodelling, particularly right ventricular outflow tract (RVOT) dilation. Recent studies have also shown that peak RV longitudinal strain (Sl) measured by speckle tracking echocardiography (STE) is reduced in adolescents with definite and borderline ACM. The prevalence of RV changes meeting ACM criteria in healthy paediatric athletes, and whether these changes are associated with abnormal RV strain values is not known.

Purpose

The aim of this study is to evaluate the prevalence of healthy paediatric athletes meeting the ACM echocardiographic modified Task Force Criteria (mTFC) for RVOT dilation, and how this relates to RV longitudinal systolic function.

Methods

Athletes under 18 years old undergoing comprehensive pre-participation screening (2014-2017) at two sports academies were included. Global (RV-Sl) and free wall peak systolic strain (FW-Sl) were calculated using STE. Three groups were defined: meeting the major mTFC for RVOT size (M-mTFC), meeting the minor mTFC (m-mTFC) and not meeting the mTFC (no-mTFC). RV-Sl and FW-Sl were compared using the Kruskall Wallis test.

Results

A total of 247 boys (11.1-18 years, median 14.6 years) were included, with diverse ethnicity (53.1% Arab, 27.6% Black, 17.6% White, and 1.7% other) and sports background (50.6% football, 27.9% athletics, 21.5% other).

Of these n = 22 were in the M-mTFC group (8.9%), n = 93 in the m-mTFC group (37.7%) and n = 132 in the no-mTFC group (53.4%). No regional RV wall motion abnormalities were observed. There were no differences in RV-Sl or FW-Sl by mTFC Group (Table 1).

Conclusions

In healthy paediatric athletes, 9% met the major mTFC, and 38% met the minor mTFC for RVOT size. RV longitudinal strain was found to be similar between those who met the mTFC and those who did not. This highlights the probable non-pathological adaptations reflected by RVOT dilation in these individuals, as opposed to those seen in ACM. The results of this study suggest that STE can be a valuable tool in ACM screening in paediatric athletes, especially in cases where RV remodelling is present.

RV peak longitudinal strain by mTFC All M-mTFC n = 22 m-mTFC n = 93 no-mTFC n = 132 p value for between group comparison Global RV Sl (median, IQR) -23.3% (-25.2;-21.7) -23.3% (-25.5;-21.7) -23.4% (-25;-21.7) -23.3% (-25.5;-21.7) p = 0.8 Free wall RV Sl (median, IQR) 27.7% (-30;-25.2) -27.6% (-29.3;-25.2%) -28.1% (-29.7;-25) -27.5 (-30.5;-25.4) p = 0.9

Swelling-Based Distributed Chemical Sensing with Standard Acrylate Coated Optical Fibers

Distributed chemical sensing is demonstrated using standard acrylate coated optical fibers. Swelling of the polymer coating induces strain in the fiber’s silica core provoking a local refractive index change which is detectable all along an optical fiber by advanced distributed sensing techniques. Thermal effects can be discriminated from strain using uncoated fiber segments, leading to more accurate strain readings. The concept has been validated by measuring strain responses of various aqueous and organic solvents and different chain length alkanes and blends thereof. Although demonstrated on a short range of two meters using optical frequency-domain reflectometry, the technique can be applied to many kilometer-long fiber installations. Low-cost and insensitive to corrosion and electromagnetic radiation, along with the possibility to interrogate thousands of independent measurement points along a single optical fiber, this novel technique is likely to find applications in environmental monitoring, food analysis, agriculture, water quality monitoring, or medical diagnostics.

Surgical management of complete atrioventricular septal defect with tetralogy of Fallot: results from a national audit database

Background

Complete atrioventricular septal defect (CAVSD) with tetralogy of Fallot (CAVSD-ToF) is an uncommon association, and the management is more difficult than for each lesion in isolation. Depending on the anatomy, clinical status and ventricular morphology, definitive repair is offered either as staged or single operation with few undergoing single or one and a half ventricle procedures. Currently available data are limited to single centre studies.

Purpose

We aim to use data from a national audit dataset to describe outcomes in the surgical management of CAVSD-ToF with data from the national audit.

Methods

All children with CAVSD and tetralogy of Fallot (including double outlet right ventricle and pulmonary atresia variants) undergoing the first cardiac procedure between 2000–2013 were included and all subsequent procedures extracted. Three treatment pathways were defined: definitive primary procedure (“primary complete repair”), staged repair or “unbalanced ventricles repair” (Glenn shunt or modified Fontan). Continuous data is expressed as median (range). Survival data obtained using the Kaplan Meier method and subgroup comparisons done using the log-rank test.

Results

A total of 125 patients were included, 50.4% male, first procedure at 150 (1–2770) days. Down syndrome was present in 79.4% (63/79 of those with reported non-cardiac comorbidities), while 8% (10/125) had heterotaxy syndrome. “Primary complete repair” was performed in 40% (n=50), at 319 (33–2770) days. Staged repair was undertaken in 28% (n=35), first palliation at 80 (1–733) days. An “unbalanced ventricles” approach was used in 16.8% (n=21), first procedure at 135 (1–1742) days). The other 15.2% (n=19), first procedure at 53 (range 1–436) days, had at least one palliation procedure, but no identifiable committed pathway.

Survival at 5 years from the first procedure in “primary complete repair” compared to the remainder of the group is shown in the Figure. No significant differences in survival were found. Specifically in the “unbalanced ventricle repair” group, just 1 patient died during follow-up.

A total of 85 patients (68%) achieved either primary or staged “complete repair”. Early mortality (30 day) after the “complete repair” was 6.6% (similar for both approaches, p=0.9). Survival at 5 years after “complete repair” was 82.7% (similar for both approaches, p=0.8). Freedom from any cardiac re-intervention at 5 years was 69.5% (77.6% after primary, 58.1% after staged repair, p=0.03).

Conclusion

Early-life mortality in this heterogeneous group of CAVSD-ToF remains high, even in patients receiving definitive “complete repair”. We found no survival differences in the medium term between primary repair and a palliation approach, but more cardiac re-interventions were undertaken after staged complete repair. Surprisingly good results were seen in the unbalanced ventricles group, but longer follow up is needed to examine their attrition and longer term outcome.

Survival at 5 years by treatment option

Funding Acknowledgement

Type of funding source: None

Eighteen Months Follow-Up with Patient-Centered Outcomes Assessment of Complete Dentures Manufactured Using a Hybrid Nanocomposite and Additive CAD/CAM Protocol

Abstract: The present study aimed to assess the eighteen month follow-up patient-centered outcomes of a simple and predictable protocol for 3D-printed functional complete dentures manufactured using an improved poly(methyl methacrylate) (PMMA)-nanoTiO2. A detailed morphological and structural characterization of the PMMA-TiO2 nanocomposite, using SEM, EDX, XRD, and AFM, after 3D-printing procedure and post-wearing micro-CT, was also performed.

METHODS

A total of 35 fully edentulous patients were enrolled in this prospective study. A 0.4% TiO2-nanoparticle-reinforced PMMA composite with improved mechanical strength, morphologically and structurally characterized, was used according to an additive computer-aided design and computer-aided manufacturing (CAD/CAM) protocol for complete denture fabrication. The protocol proposed involved a three-step appointment process. Before denture insertion, 1 week, 12 month, and 18-month follow up patients were evaluated via the Visual Analogue Scale (VAS, 0-10) and Oral Health Impact Profile for Edentulous Patients (OHIP-EDENT), with a higher score meaning poor quality of life.

RESULTS

A total of 45 complete denture sets were inserted. OHIP-EDENT scored significantly better after 18 months of denture wearing, 20.43 (±4.42) compared to 52.57 (±8.16) before treatment; mean VAS was improved for all parameters assessed.

CONCLUSIONS

Within the limitations of this study, we can state that the proposed workflow with the improved material used is a viable treatment option for patients diagnosed with complete edentulism.

Solar physical vapor deposition preparation and microstructural characterization of TiO2 based nanophases for dye-sensitized solar cell applications

Titanium dioxide exists in three crystalline phases: anatase, rutile and brookite. Although rutile is thermodynamically more stable, anatase is considered as the most favorable phase for photocatalysis and solar energy conversion. Recent studies have shown a significant improvement of light harvesting and overall solar conversion efficiency of anatase nanoparticles in dye-sensitized solar cells (DSSCs) when using a mixture of anatase and rutile phases (10-15% rutile). TiO2 nanopowders have been prepared by a solar physical vapor deposition process (SPVD). This method has been developed in Odeillo-Font Romeu France using "heliotron" solar reactors working under concentrated sunlight in 2 kW solar furnaces. By controlling reactor's atmosphere type (air/argon) and gas pressure, several types of anatase/rutile nanophases have been obtained with slightly different microstructural properties and morphological characteristics. X-ray diffraction analyses (XRD) were performed on precursor and on the SPVD obtained nanopowders. Information concerning their phase composition and coherence diffraction domain (crystallites size and strain) was obtained. Nanopowders morphology has been studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM).