Direct Visualization of Chemical Transport in Solid-State Chemical Reactions by Time-of-Flight Secondary Ion Mass Spectrometry

Systematic control and design of solid-state chemical reactions are required for modifying materials properties and in novel synthesis. Understanding chemical dynamics at the nanoscale is therefore essential to revealing the key reactive pathways. Herein, we combine focused ion beam-scanning electron microscopy (FIB-SEM) and time-of-flight secondary ion mass spectrometry (TOF-SIMS) to track the migration of sodium from a borate coating to the oxide scale during in situ hot corrosion testing. We map the changing distribution of chemical elements and compounds from 50 to 850 °C to reveal how sodium diffusion induces corrosion. The results are validated by in situ X-ray diffraction and post-mortem TOF-SIMS. We additionally retrieve the through-solid sodium diffusion rate by fitting measurements to a Fickian diffusion model. This study presents a step change in analyzing microscopic diffusion mechanics with high chemical sensitivity and selectivity, a widespread analytical challenge that underpins the defining rates and mechanisms of solid-state reactions.

Band Engineering Through Pb-Doping of Nanocrystal Building Blocks to Enhance Thermoelectric Performance in Cu3 SbSe4

Developing cost-effective and high-performance thermoelectric (TE) materials to assemble efficient TE devices presents a multitude of challenges and opportunities. Cu3 SbSe4 is a promising p-type TE material based on relatively earth abundant elements. However, the challenge lies in its poor electrical conductivity. Herein, an efficient and scalable solution-based approach is developed to synthesize high-quality Cu3 SbSe4 nanocrystals doped with Pb at the Sb site. After ligand displacement and annealing treatments, the dried powders are consolidated into dense pellets, and their TE properties are investigated. Pb doping effectively increases the charge carrier concentration, resulting in a significant increase in electrical conductivity, while the Seebeck coefficients remain consistently high. The calculated band structure shows that Pb doping induces band convergence, thereby increasing the effective mass. Furthermore, the large ionic radius of Pb2+ results in the generation of additional point and plane defects and interphases, dramatically enhancing phonon scattering, which significantly decreases the lattice thermal conductivity at high temperatures. Overall, a maximum figure of merit (zTmax ) ≈ 0.85 at 653 K is obtained in Cu3 Sb0.97 Pb0.03 Se4 . This represents a 1.6-fold increase compared to the undoped sample and exceeds most doped Cu3 SbSe4 -based materials produced by solid-state, demonstrating advantages of versatility and cost-effectiveness using a solution-based technology.

Recycling Waste Glyceroborate to Aqueous Lubricant for Tribological Applications

The present study attempts to explore the direct recyclability of glyceroborate from medicine pharmaceutical production wastewater into an aqueous lubricant instead of conventional waste processing methods from the tribological view. In order to determine the tribological feasibility, the physicochemical properties of crude pharmaceutical wastewater are investigated and compared with those of pure glycerol to access their potential lubrication properties. The results demonstrated that the crude pharmaceutical wastewater has better friction-reducing and antiwear properties under the same working conditions. Besides outstanding lubricating properties, the friction-induced formation of borate tribo-film and intermediate FeOOH compound favors lowering of the shear stress between the rubbing surfaces. This finding better provides an alternative to transform glyceroborate from medicine pharmaceutical production wastewater after simple distillation processing to a potential aqueous lubricant.

Surface Chemistry and Band Engineering in AgSbSe2: Toward High Thermoelectric Performance

AgSbSe₂ is a promising thermoelectric (TE) p-type material for applications in the middle-temperature range. AgSbSe₂ is characterized by relatively low thermal conductivities and high Seebeck coefficients, but its main limitation is moderate electrical conductivity. Herein, we detail an efficient and scalable hot-injection synthesis route to produce AgSbSe₂ nanocrystals (NCs). To increase the carrier concentration and improve the electrical conductivity, these NCs are doped with Sn²⁺ on Sb³⁺ sites. Upon processing, the Sn²⁺ chemical state is conserved using a reducing NaBH₄ solution to displace the organic ligand and anneal the material under a forming gas flow. The TE properties of the dense materials obtained from the consolidation of the NCs using a hot pressing are then characterized. The presence of Sn²⁺ ions replacing Sb³⁺ significantly increases the charge carrier concentration and, consequently, the electrical conductivity. Opportunely, the measured Seebeck coefficient varied within a small range upon Sn doping. The excellent performance obtained when Sn²⁺ ions are prevented from oxidation is rationalized by modeling the system. Calculated band structures disclosed that Sn doping induces convergence of the AgSbSe₂ valence bands, accounting for an enhanced electronic effective mass. The dramatically enhanced carrier transport leads to a maximized power factor for AgSb_0.98Sn_0.02Se₂ of 0.63 mW m^-1 K^-2 at 640 K. Thermally, phonon scattering is significantly enhanced in the NC-based materials, yielding an ultralow thermal conductivity of 0.3 W mK^-1 at 666 K. Overall, a record-high figure of merit (zT) is obtained at 666 K for AgSb_0.98Sn_0.02Se₂ at zT = 1.37, well above the values obtained for undoped AgSbSe₂, at zT = 0.58 and state-of-art Pb- and Te-free materials, which makes AgSb_0.98Sn_0.02Se₂ an excellent p-type candidate for medium-temperature TE applications.

Dioscorea nipponica Makino Relieves Ovalbumin-Induced Asthma in Mice through Regulating RKIP-Mediated Raf-1/MEK/MAPK/ERK Signaling Pathway

Purpose

Dioscorea nipponica Makino (DNM) is a traditional herb with multiple medicinal functions. This study is aimed at exploring the therapeutic effects of DNM on asthma and the underlying mechanisms involving RKIP-mediated MAPK signaling pathway.

Methods

An ovalbumin-induced asthma model was established in mice, which was further administrated with DNM and/or locostatin (RKIP inhibitor). ELISA was performed to detect the serum titers of OVA-IgE and OVA-IgG1, bronchoalveolar lavage fluid (BALF) levels of inflammation-related biomarkers, and tissue levels of oxidative stress-related biomarkers. The expression of RKIP was measured by quantitative real-time PCR, Western blot, immunohistochemistry, and immunofluorescence. HE staining was used to observe the pathological morphology of lung tissues. The protein expression of MAPK pathway-related proteins was detected by Western blot.

Results

Compared with the controls, the model mice exhibited significantly higher serum titers of OVA-IgE and OVA-IgG1, BALF levels of IL-6, IL-8, IL-13, TGF-β1, and MCP-1, tissue levels of MDA and ROS, lower BALF levels of IL-10 and IFN-γ, and tissue level of GSH. DNM relieved the allergic inflammatory response and oxidative stress in the model mice. DNM also recovered the downregulation of RKIP and the pathological injury of lung tissues in asthma mice. In addition, the Raf-1/MEK/MAPK/ERK pathway in the model mice was blocked by DNM. Silencing of RKIP by locostatin weakened the relieving effects of DNM on asthma through activating the Raf-1/MEK/MAPK/ERK pathway.

Conclusion

DNM relieves asthma via blocking the Raf-1/MEK/MAPK/ERK pathway that mediated by RKIP upregulation.

Survival Outcome with Routine Clinical Use of 82Rb PET/CT Myocardial Blood Flow (MBF) Quantification

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): NIHR Biomedical Research Centre, University College London Hospitals

Background

The prognostic value of 82Rb PET/CT derived myocardial blood flow (MBF) is increasingly recognised in both general and specific cardiovascular populations.

Purpose

This study investigates the prognostic potential of MBF in a large cohort of patients undergoing routine 82Rb PET/CT examination.

Methods

1148 consecutive patients (687 males, mean age 64 +/- 12 years) whom had been referred for 82Rb PET/CT examination in a single centre were included in this study.  All patients completed a stress 82Rb PET/CT with adenosine infusion, paired with a rest study.  Dynamic PET acquisitions were performed in both. Cardiovascular risk factors were documented as per clinical routine. Images were checked for quality and analysed using a proprietary software by an experienced operator to derive MBF parameters.  Overall survival was recorded following the study.

Results

Median follow-up period was 71 +/- 28 months.  Mean survival was 121 (95% CI: 118-124) months. On univariate analysis, global myocardial flow reserve <1.77 was associated with a higher all-cause mortality (p < 0.001). Other parameters including higher age (> =76 years), lower BMI (<21), qualitative abnormality on the myocardial perfusion scan (MPS), low hyperaemic ejection fraction on the gated studies (stress < 37 and rest < 34). Patients being on cardiac glycosides and diuretics were also significant predictor of poor prognosis (p < 0.001) on univariate analysis, presumably reflecting underlying arrhythmia and heart failure. A multivariate Cox regression analysis (step-wise Forward Wald), comprising of the above significant univariate markers, highlighted global myocardial flow reserve (HR: 2.6, 95%CI: 1.8-3.6, p < 0.001), age (HR: 2.8, 95%CI: 2.0-3.9, p < 0.001),, BMI (HR: 2.7, 95%CI: 1.7-4.1, p < 0.001),, ejection fraction (stress - HR: 3.3, 95%CI: 2.3-4.8, p < 0.001), MPS (HR: 1.5, 95%CI: 1.1-2.1, p = 0.024), and patients on diuretics (HR: 1.8, 95%CI: 1.2-2.5, p = 0.003) were independent predictors of overall survival (overall model: p < 0.001)

Discussion

We show that high volume routinely derived MBF in patients undergoing 82Rb PET/CT is a strong predictor of mortality and independent of other risk factors. This has important clinical implication for measuring not only interventional treatment but also measuring the effect of lifestyle and medical strategies.

Comprehensive mechanical & metabolic imaging of abdominal aortic aneurysm with 4D flow/ FDG PET on an integrated PETMRI: a feasibility study

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): NIHR Biomedical Research Centre, University College London Hospitals.

Background

A number of non-invasive imaging derived parameters have been implicated in the development and progression of abdominal aortic aneurysm, although the mechanism, and relationships of many of these are yet to be precisely determined.  Mechanical parameters can now be studied using 4D phase contrast magnetic resonance (PCMR), and inflammatory cellular activity can be detected with FDG PET.

Purpose

It may be postulated that inflammation of the aortic wall may be the intermediary at the tissue level linking mechanical wall shear stress (WSS) to aneurysm progression. It may be feasible to study 4D PCMR and FDG PET at the same patient visit on a PETMRI platform, with the potential to enhance temporal and spatial co-registration and improving the understanding of any relationship between these two parameters.  Our study aims to assess feasibility of studying these on an integrated PETMRI system.

Methods

7 patients with known aortic aneurysm were recruited in a vascular ultrasound screening follow up clinic.  During a single visit following 6 hours fasting, all patients underwent FDG injection and 60 minutes uptake period.  With quiet breathing, list mode PET acquisition and concurrent 4D PCMR was acquired using stacks of spiral acquisition, with ECG trace information for retrospective gating.  Images from the 4D PCMR and FDG PET were assessed qualitatively for image quality and visual matching.

Results

All 7 patients completed the study.  Overall image quality was adequate to good.  There is qualitatively a good concordance with impression of positive correlation between wall shear stress and inflammatory signal (see attached image).

Conclusion

We have demonstrated feasibility of combined assessment of mechanical and metabolic imaging parameters using an integrated PETMRI system.  Initial findings show there to be a broad concordance of wall shear stress and inflammatory signal in the abdominal aneurysm.

Novel double injection technique for sentinel lymph node biopsy in oral cancer

The development of new lymphatic tracers and the advancement of hybrid tracers, such as indocyanine green (ICG)-Nanocoll (GE Healthcare), represent an exciting step in the future of sentinel lymph node biopsy (SLNB). These tracers aim to improve our ability to detect sentinel lymph nodes by enhancing their localisation. The aim of this study was to assess the performance of a novel dual tracer, double injection technique of ICG-'cold'-Nanocoll and radiolabelled Nanocoll, in SLNB for early-stage oral cancer. A double injection technique was performed first using ^99mTc-Nancoll prior to sentinel node imaging followed by ICG-'cold'-Nanocoll injection in theatre. Analysis involved examination of the number, labelling, and location of the nodes harvested, sentinel node status, survival analysis, false negative rate, and complications associated with use of the technique. ICG 'cold' Nanocoll results showed concordance of fluorescence and radioactivity detection in 74 nodes in 24 patients. Most importantly, all nodes found positive for metastasis (6 nodes) were discovered to be both 'hot' and fluorescent; 74 nodes removed were both 'hot' and fluorescent, eight fluorescent only and six 'hot' only. Our results indicate that two sets of tracer injections given at two different time points will flow to the same sentinel nodes. This double labelling increased our confidence that the retrieved node was a sentinel node.

Autologous manganese phosphates with different Mn sites for electrocatalytic water oxidation

Herein, we report two autologous phosphates obtained from the same parent material for electrocatalytic water oxidation. These two phosphates have many similarities except the coordination structure of the Mn centers. It has been straightforwardly observed that the highly asymmetric geometry of Mn2P2O7 can stabilize the active Mn(iii) to promote water oxidation.

[Hepatic echinococcus granulosus: a clinicopathological analysis of thirteen cases]

Objective: To investigate the clinicopathologic characteristics of hepatic echinococcus granulosus (HEG). Methods: Thirteen cases of HEG were collected from Linzhi People's Hospital between January 2017 to October 2020, and their clinicopathologic features, ultrasound classification, immunophenotype and histochemical data were analyzed, retrospectively and the relevant literature was reviewed. Results: Thirteen patients (5 male patients, 8 female patients) were included in this cohort, and the mean age was 40 years. The most common clinical presentation was mild abdominal distention and pain (9/13). Based on WHO-IWGE ultrasound standardized classification, these cases were classified into 5 types, including type CL (1 case), type CE1 (2 cases), type CE2 (4 cases), type CE3 (3 cases) and type CE4 (3 cases). Gross examination revealed a solitary cyst localized in the liver, varying from 2.7 to 13.5 cm in diameter, and most of them(10/13)were more than 10 cm. Histopathologically, these cysts possessed a thin inner germinal layer and outer adventitial layer, and a central cavity filled with a clear"hydatid"fluid. The germinal layer was continuous and generated brood capsules and protoscoleces. The laminated membranes were clearly demonstrated by elastic fiber and Gomori's stains. Inside the"mother"cyst, there were a varying number of"daughter"vesicles of variable sizes. The inflammatory reaction around the cyst consisted of eosinophils, mononuclear cells immediately next to the cyst layer and sometimes formed granuloma and giant cells resembling the Langhan's type giant cells. The lymphoid cells were positive for CD20 and CD3. The CD68 immunohistochemistry clearly demonstrated epithelioid cells of granuloma in two cases. Moreover, immunohistochemistry revealed plasma cells were locally positive for CD38, IgG and IgG4, but not meeting the criteria for IgG4 related lesion. Conclusions: Hepatic echinococcus granulosus is a zoonotic parasitic disease prevalent in pastoral areas such as Tibet. It is important to understand its clinical features, ultrasound characteristics and histological morphology.

Unilateral axillary adenopathy following COVID-19 vaccination: a multimodality pictorial illustration and review of current guidelines

We present a multimodality pictorial review of axillary lymphadenopathy in patients recently vaccinated against COVID-19. As the mass vaccination programme continues to be rolled out worldwide in an effort to combat the pandemic, it is important that radiologists consider recent COVID-19 vaccination in the differential diagnosis of unilateral axillary lymphadenopathy and are aware of typical appearances across all imaging methods. We review current guidelines on the management of unilateral axillary lymphadenopathy in the context of recent COVID-19 vaccination.

Distributions of serum thyroid-stimulating hormone in 2020 thyroid disease-free adults from areas with different iodine levels: a cross-sectional survey in China

PURPOSE

The aim of the present study was to describe the distributions of serum thyroid- stimulating hormone (TSH) levels in thyroid disease-free adults from areas with different iodine levels in China. Meanwhile, we aimed to evaluate the influence of age and gender on the distribution of TSH, assess the relationship between concentrations of TSH and free thyroxine (FT₄), and analyze the factors that may affect TSH levels.

METHODS

2020 adults were included from April 2016 to June 2019. Urinary iodine concentration, serum iodine concentration, serum TSH, FT₄, free triiodothyronine, thyroid peroxidase antibodies and thyroglobulin antibodies were measured, and thyroid ultrasonography was performed.

RESULTS

The median of TSH in iodine-fortification areas (IFA), iodine-adequate areas (IAA), iodine-excessive areas (IEA) were 2.32, 2.11 and 2.34 mIU/L, respectively. Serum TSH concentrations were significantly higher in IFA and IEA than that in IAA (p = 0.005 and < 0.0001). The TSH values of most adults were distributed within the range of 1.01-3.00 mIU/L with the same trend in three groups. In our study, TSH levels did not change with age, and the TSH level of females was higher than that of males (p < 0.0001). There was a negative correlation between FT₄ and TSH in IAA (r = - 0.160, p < 0.0001) and IEA (r = - 0.177, p < 0.0001), but there was no correlation between FT₄ and TSH in IFA (r = - 0.046, p = 0.370). BMI, smoking status, education levels, and marital status were associated with TSH.

CONCLUSION

Our study provides a basis for establishing the reference intervals of TSH in different iodine level areas.

Smart-Responsive Colloidal Capsules as an Emerging Tool to Design a Multifunctional Lubricant Additive

The microencapsulation technique has been proven as a powerful and flexible tool to design and develop a multifunctional additive for various applications. The significant characteristics of this technique center around the ability to control the release of the core active ingredients by tuning the porosity and the permeability of the shell. However, this original concept has faced a major roadblock in lubricant research since it causes a major breakage of the microcapsules (∼70%) under severe stressed-shearing conditions. The shell fragments generated from such unwanted events significantly influence the friction and wear performances of the counterpart, thus limiting the ongoing research of the microencapsulation technique in tribology. To solve such technical bottlenecks, we develop a new strategy of utilizing the microencapsulation technique which focuses on the smart responsiveness of the shell with the base lubricant and the synergy between the incorporated materials. In this study, the smart-responsive colloidal capsule has been developed based on our proposed concept that demonstrates outstanding performances in improving the lubricity of the conventional melt lubricant (by ∼70%) under hot metal working conditions. An unprecedented oxidation-reduction (by ∼93%) and the first instance of ultralow friction (0.07) at elevated temperatures (880 °C) have been initially achieved. This work opens a new avenue of customizing a multifunctional additive package by utilizing the smart colloidal capsules in lubrication science.

Can deep learning identify normal coronary flow reserve from rubidium myocardial PET perfusion?

Funding Acknowledgements

Type of funding sources: None.

Background

Impaired vasodilator function is an early manifestation of coronary artery disease (CAD) and may precede angiographic stenosis.  Rest and stress myocardial blood flow (MBF) are calculated from dynamic imaging during rest/stress Rubidium (Rb) myocardial PET perfusion.  Coronary flow reserve (CFR) equals stress divided by rest MBF.  CFR is an independent predictor of cardiac mortality in patients with known or suspected CAD.  We evaluated the prediction of CFR from analysis of stress/rest PET images by deep learning (DL) as compared with standard calculation of CFR using supervised learning applied methodology using within a commercial DL training platform.

Methods

1036 patients (625 male, 411 female, mean age: 64.3 years old) were studied. Patients underwent Stress/rest Rb PET perfusion, and CFR calculated using MBF software by an expert user. Abnormal CFR was defined as &lt;2.0. The left ventricle myocardium was segmented using standard software.

DL was trained using polar distribution of normalized PET uptake at stress and rest, processed stress and rest images were cropped, the stress images were then subtracted from the rest images. DL was trained using 935 subtracted images and tested using the remaining 101 images. DL was trained with supervision to classify images. The image shows examples of subtracted  abnormal cases (1a & 1b).

Results

Using our supervised training methodology, the commercial MBF software platform reported 465 cases as abnormal, with 48 of these were included in the DL test set. The DL platform produced abnormal output classifiers for all the whole test set. DL accurately detected over 70% of abnormal cases.

The commercial MBF software reported 571 cases as normal; with 50 of these contributing to the DL test set. DL was accurate in 48.0% of normal cases. Statistical results are shown in the table.

Conclusion

We have shown the proof of concept that DL algorithms trained with supervision can detect abnormal CFR. Our work shows that further work is needed to develop supervised learning methodology in order to improve accuracy for clinical use.

Statistical Results Statistic Value Sensitivity 63.16% Specificity 56.67% + Predictive Value 48.00% - Predictive Value 70.83% Accuracy 59.18% Abstract Figure.

Paediatric Molecular Radiotherapy: Challenges and Opportunities

The common contemporary indications for paediatric molecular radiotherapy (pMRT) are differentiated thyroid cancer and neuroblastoma. It may also have value in neuroendocrine cancers, and it is being investigated in clinical trials for other diseases. pMRT is the prototypical biomarker-driven, precision therapy, with a unique mode of delivery and mechanism of action. It is safe and well tolerated, compared with other treatments. However, its full potential has not yet been achieved, and its wider use faces a number of challenges and obstacles. Paradoxically, the success of radioactive iodine as a curative treatment for metastatic thyroid cancer has led to a 'one size fits all' approach and limited academic enquiry into optimisation of the conventional treatment regimen, until very recently. Second, the specialised requirements for the delivery of pMRT are available in only a very limited number of centres. This limited capacity and geographical coverage results in reduced accessibility. With few enthusiastic advocates for this treatment modality, investment in research to improve treatments and broaden indications from both industry and national and charitable research funders has historically been suboptimal. Nonetheless, there is now an increasing interest in the opportunities offered by pMRT. Increased research funding has been allocated, and technical developments that will permit innovative approaches in pMRT are available for exploration. A new portfolio of clinical trials is being assembled. These studies should help to move at least some paediatric treatments from simply palliative use into potentially curative protocols. Therapeutic strategies require modification and optimisation to achieve this. The delivery should be personalised and tailored appropriately, with a comprehensive evaluation of tumour and organ-at-risk dosimetry, in alignment with the external beam model of radiotherapy. This article gives an overview of the current status of pMRT, indicating the barriers to progress and identifying ways in which these may be overcome.

Porosity-induced mechanically robust superhydrophobicity by the sintering and silanization of hydrophilic porous diatomaceous earth

HYPOTHESIS

Because they have self-similar low-surface-energy microstructures throughout the whole material block, fabricating superhydrophobic monoliths has been currently a promising remedy for the mechanical robustness of non-wetting properties. Noticeably, porous materials have microstructured interfaces throughout the complete volume, and silanization can make surfaces low-surface-energy. Therefore, the porous structure and surface silane-treatment can be combined to render hydrophilic inorganics into mechanically durable superhydrophobic monoliths.

EXPERIMENTS

Superhydrophobic diatomaceous earth pellets were produced by thermal-sintering, followed by a silanization process with octyltriethoxysilane. The durability of superhydrophobicity was evaluated by changes in wetting properties, surface morphology, and chemistry after a systematic abrasion sliding test.

FINDINGS

The intrinsic porosity of diatomite facilitated surface silanization throughout the whole sintered pellet, thus producing the water-repelling monolith. The abrasion sliding converted multimodal porosity of the volume to hierarchical roughness of the surface comprised of silanized particles, thereby attaining superhydrophobic properties of high contact angles over 150° and sliding angles below 20°. The tribological properties revealed useful information about the superhydrophobicity duration of the non-wetting monolith against friction. The result enables the application of porous structures in the fabrication of the anti-abrasion superhydrophobic materials even though they are originally hydrophilic.

Intrinsic Effect of Alkali Concentration on Oxidation Reactivity and High-Temperature Lubricity of Silicate Melts between Rubbed Steel/Steel Contacts

The present study investigated oxidation reactivity and hot lubricity of a sodium silicate melt at different Na₂O/SiO₂ ratios under elevated temperature stimulation. Static oxidation prevention was achieved at 920 °C when the Na₂O/SiO₂ ratio reached 1:3 (trisilicate) and 1:2 (disilicate), but it started to deteriorate in the case of 1:1 (metasilicate). At a high concentration of sodium (metasilicate), a severe corrosion reaction between the melt and oxide took place that resulted in a composite coating on the steel substrate. This high-temperature reaction accelerated the formation of ionic charges from the steel base and promoted oxidation. However, friction and wear reduction is proportional to an increase in the sodium oxide fraction. Metasilicate (1:1) exhibited excellent lubricity under the hot frictional test at 920 °C compared to other lubricants. It was due to the formation of the sodium-saturated surfaces and an amorphous silica layer, which was associated with the high-temperature reactivity of sodium toward the oxide surface. In addition, the NaFeO₂-Fe₂O₃ composite film, as the reaction product of individual sodium charge and oxide, plays a significant role in maintaining the tribofilm stability for metasilicate, which was not present for disilicate. This study advances the understanding of how sodium-containing compounds perform oxidation prevention and generate lubricity at hot rubbed surfaces.

Intrinsic Effect of Nanoparticles on the Mechanical Rupture of Doubled-Shell Colloidal Capsule via In Situ TEM Mechanical Testing and STEM Interfacial Analysis

The discovery of Pickering emulsion templated assembly enables the design of a hybrid colloidal capsule with engineered properties. However, the underlying mechanisms by which nanoparticles affect the mechanical properties of the shell are poorly understood. Herein, in situ mechanical compression on the transmission electron microscope and aberration-corrected scanning transmission microscope are unprecedentedly implemented to study the intrinsic effect of nanoparticles on the mechanical properties of the calcium carbonate (CaCO₃ )-decorated silica (SiO₂ ) colloidal capsule. The stiff and brittle nature of the colloidal capsule is due to the interfacial chemical bonding between the CaCO₃ nanoparticles and SiO₂ inner shell. Such bonding strengthens the mechanical strength of the SiO₂ shell (166 ± 14 nm) from the colloidal capsule compared to the thicker single SiO₂ shell (310 ± 70 nm) from the silica hollow sphere. At elevated temperature, this interfacial bonding accelerates the formation of the single calcium silicate shell, causing shell morphology transformation and yielding significantly enhanced mechanical strength by 30.9% and ductility by 94.7%. The superior thermal durability of the heat-treated colloidal capsule holds great potential for the fabrication of the functional additives that can be applied in the wide range of applications at elevated temperatures.

Benign temporomandibular joint tumours with extension to infratemporal fossa and skull base: condyle preserving approach

This article introduces a modified surgical approach combining condylotomy with posterior disc attachment release for the resection of large non-malignant masses located in the infratemporal fossa and involving the skull base. This retrospective study included 14 patients treated at Shanghai Ninth People's Hospital, Shanghai Jiao Tong University between January 2010 and December 2016. Clinical evaluations (visual analogue scale (VAS) for pain, maximum inter-incisal opening (MIO), and complications) and radiological findings (magnetic resonance imaging (MRI) and computed tomography (CT)) were collected pre- and postoperatively. All patients had satisfactory surgical exposure and complete resection of the neoplasms. During an average follow-up of 54.8 months, no clinical or radiographic signs of recurrence were reported. MIO increased from 28mm preoperatively to 35.4mm postoperatively (P<0.001). The pain VAS score changed from 5.4 preoperatively to 0.7 postoperatively (P<0.001). Neural function was normal for all patients. Postoperative MRI and CT scans showed a satisfactory disc position and condyle morphology, with no resorption. Three-dimensional reconstruction of the postoperative CT scan also demonstrated healing of the skull base defects. The modified surgical approach combining condylotomy with posterior disc attachment release is suitable for the removal of large non-malignant masses involving the infratemporal fossa and skull base.

A study on the local corrosion behavior and mechanism of electroless Ni-P coatings under flow by using a wire beam electrode

The local corrosion behavior and mechanism of Ni–P coatings in a 3.5 wt% sodium chloride solution with different flow speeds (0 m s⁻¹, 0.5 m s⁻¹, 1 m s⁻¹) were investigated through a wire beam electrode (WBE) with morphological, elemental and electrochemical analyses as well as numerical simulations. It was found that the microstructure of the Ni–P coating was in the shape of broccoli and possessed satisfactory compactness and uniformity. The numerical simulations showed that the speed increased and the static pressure decreased at the local area. Combined with WBE, it was found that the average corrosion potential decreased at that area. The results indicated that the corrosion tendency and corrosion rate of the Ni–P coating were larger at higher speeds, and the corrosion resistance could be improved by the electroless Ni–P coating. WBE was helpful in revealing the local electrochemical information of the Ni–P coating.

The local corrosion behavior and mechanism of Ni–P coatings in an NaCl solution with different flow speeds were investigated through a wire beam electrode with morphological, elemental and electrochemical analyses as well as numerical simulations.

Correction to 'Resveratrol-loaded PLGA nanoparticles: enhanced stability, solubility and bioactivity of resveratrol for non-alcoholic fatty liver disease therapy'

[This corrects the article DOI: 10.1098/rsos.181457.].

Conductive Molybdenum Sulfide for Efficient Electrocatalytic Hydrogen Evolution

Molybdenum sulfide (MoS₂ ) is a layered material with high activity for electrocatalytic hydrogen evolution reaction (HER). In conventional MoS₂ , the high electrical resistance between the layers hampers the bulk charge transfer and therefore greatly limits its performance in electrolysis. Herein, ultrathin MoS₂ nanosheets with bent layers on reduced graphene oxide (RGO) are reported. In sharp contrast to the bulk MoS₂ , the resulting MoS₂ has mostly 1 or 2 layers, and the layer distance is significantly expanded to ≈1 nm. From computational studies, the prepared MoS₂ with limited layer numbers and expanded layer distances has similar physical and chemical features with single-layer MoS₂ . Importantly, the bent single layer is electrically conductive and is intrinsically more active than a normal flat single layer. In addition, the unusual features of confined sizes and distorted lattices in the prepared MoS₂ can bring about plentiful active sites and are beneficial for mass diffusion during electrocatalysis. The hybrid material exhibits high activity for electrocatalytic HER, affording a current density of 10 mA cm^-2 at a low overpotential of 66 mV.

Depolymerization of sodium polyphosphates on an iron oxide surface at high temperature

Density functional theory (DFT) and first principles molecular dynamics (FPMD) studies of pyrophosphate cluster Na₄P₂O₇ and triphosphate cluster Na₅P₃O₁₀ absorbed and decomposed on an Fe₂O₃(0001) surface have been conducted. Comparative analyses of the structure properties and adsorption processes during the simulation at elevated temperature have been carried out. The results depict the key interactions including the covalent P-O bonds, pure ionic Na-O or Fe-O interactions. The iron oxide surface plays an important role in the bridging bond decomposition scheme which can both promote and suppress phosphate depolymerization. It is found that the chain length of polyphosphates does not have considerable effects on the decomposition of phosphate clusters. This study provides detailed insights into the interaction of a phosphate cluster on an iron oxide surface at high temperature, and in particular the depolymerization/polymerization of an inorganic phosphate glass lubricant, which has an important behavior under hot metal forming conditions.

Understanding the tribological impacts of alkali element on lubrication of binary borate melt

Melt lubricants have been regarded as an effective class to deliver lubrication on moving mechanical contacts at extreme temperatures. Among the elementary constituents, alkali elements play a critical role in governing the physical–chemical characteristics of the lubricant despite the obscurity regarding their intrinsic roles on the rubbing interfaces. The present study attempts to unfold the effects of sodium on the tribological responses of mating steel pair under borate melt lubrication. It has been found that the involvement of Na inspires a total reversal in lubricating potentials of the lone B₂O₃ melt manifested by remarkable friction reduction, wear inhibition and prolonged load-bearing capacity. These exceptional performances are attributed to the accretion of nanothin Na layers on the contact interfaces. The interfacial occurrences are interpreted from a physico-chemistry perspective while the influences of surface microstructure are also discussed in detail. Multiple characterizations are employed to thoroughly examine the sliding interfaces in multi-dimensions including Scanning Electron Microscopy (SEM), Scanning Transmission Electron Microscopy (STEM) and Atomic Force Microscopy (AFM). In addition, chemical fingerprints of relevant elements are determined by Energy Dispersive Spectroscopy (EDS) and Electron Loss Energy Spectroscopy (EELS).

The involvement of sodium induces dramatic transformation in lubrication potentials of boron oxide melt.

High Fructose and High Fat Exert Different Effects on Changes in Trabecular Bone Micro-structure

OBJECTIVES

To compare the effects of high-fat diet (HFD) and high-fructose diet (HFrD) on bone metabolism at different time points, dynamically observe the bone histology and femur trabecular micro-architecture, and analyze the underlying mechanisms.

METHODS

Sixty -Five male 6- to 7-week-old C57BL/6J mice were given HFD, HFrD, or standard diets (SD) for 8, 16, and 24 weeks. Micro-computed tomography (μCT) and bone histology were used to measure bone mass and trabecular micro-structure. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to determine the expression of genes related to bone and lipid metabolisms.

RESULTS

Compared to SD mice, femoral trabecular bone mass was significantly increased in both HFrD mice and HFD mice at 8 weeks, it continued to be higher in HFrD mice at 16 and 24 weeks with the highest level at 16 weeks, but it was significantly decreased in HFD mice at 16 and 24 weeks. HFD mice showed more epididymal fat accumulation than HFrD mice. mRNA expression of Runx2 was up-regulated at 8 and 16 weeks, but down-regulated at 24 weeks similarly in both HFrD mice and HFD mice. mRNA expression of MMP9 and CTSK was up-regulated at 8 and 16 weeks in HFD mice, but down-regulated at 24 weeks in both HFrD mice and HFD mice.

CONCLUSIONS

Our data indicated that the HFrD and HFD had different modulating effects on bone mass. After short-term feeding, both HFrD and HFD showed positive effects on bone mass; however, after long-term feeding, bone mass was decreased in HFD mice. In contrast, the bone mass was first increased and then decreased in the HFrD mice. On the basis of these findings, we speculated that chronic consumption of fat and fructose would exert detrimental effects on bone mass which might a combination action of body mass, fat mass, and bone formation/bone resorption along with proinflammatory factor and bone marrow environment.

Tribochemistry of adaptive integrated interfaces at boundary lubricated contacts

Understanding how an adaptive integrated interface between lubricant additives and solid contacts works will enable improving the wear and friction of moving engine components. This work represents the comprehensive characterization of compositional and structural orientation at the sliding interface from the perspective of surface/interface tribochemistry. The integrated interface of a lubricant additive-solid resulting from the friction testing of Graphite-like carbon (GLC) and PVD-CrN coated rings sliding against cast iron under boundary lubrication was studied. The results indicate that in the case of the CrN/cast iron pair the antiwear and friction behavior were very strongly dependent upon lubricant. In contrast, the tribology of the GLC surface showed a much lower dependence on lubrication. In order to identify the compounds and their distribution across the interface, x-ray microanalysis phase mapping was innovatively applied and the principle of hard and soft acids and bases (HSAB) to understand the behaviour. Phase mapping clearly showed the hierarchical interface of the zinc-iron polyphosphate tribofilm for various sliding pairs and different sliding durations. This interface structure formed between lubricant additives and the sliding surfaces adapts to the sliding conditions – the term adaptive interface. The current results help explain the tribology of these sliding components in engine.

Evaluation of a visual tool co-developed for training hospital staff on the prevention and control of the spread of healthcare associated infections

BACKGROUND

Staff training in infection prevention and control (IPC) across hospital settings has a crucial role in reducing the incidence of healthcare associated infections (HAIs). However the application of dynamic visualisation approaches in this context is under-developed, with very few in-depth evaluation studies of related processes and impacts.

METHODS

A prototype training tablet app for hospital staff, using interactive visuals was developed and evaluated. To demonstrate different pathogen behaviour, dynamic visualisations of norovirus, Clostridium difficile, and MRSA were developed in relation to location, survival and transmission within a virtual hospital ward model using evidence-based microbiological and staff behavioural data. A three-stage evaluation process was designed, involving a mixed sample of UK National Health Service staff (doctors, nurses and domestic staff, n = 150).

RESULTS

Participants reported improved awareness and understanding of the pathogens responsible for HAI, the types of information relevant for different staff cohorts, those aspects of the visualisations which worked well and those which were prone to cause misunderstandings, and suggestions for further development and improvement. The tool appeared to offer staff a new perspective on pathogens, being able to 'see' them contextualised in the virtual ward, making them seem more real.

CONCLUSION

Results showed the benefits of a detailed co-development process and a more contextualised understanding of the potential for visual apps to be used in IPC training.

Hierarchical Co(OH)F Superstructure Built by Low-Dimensional Substructures for Electrocatalytic Water Oxidation

The development of new materials/structures for efficient electrocatalytic water oxidation, which is a key reaction in realizing artificial photosynthesis, is an ongoing challenge. Herein, a Co(OH)F material as a new electrocatalyst for the oxygen evolution reaction (OER) is reported. The as-prepared 3D Co(OH)F microspheres are built by 2D nanoflake building blocks, which are further woven by 1D nanorod foundations. Weaving and building the substructures (1D nanorods and 2D nanoflakes) provides high structural void porosity with sufficient interior space in the resulting 3D material. The hierarchical structure of this Co(OH)F material combines the merits of all material dimensions in heterogeneous catalysis. The anisotropic low-dimensional (1D and 2D) substructures possess the advantages of a high surface-to-volume ratio and fast charge transport. The interconnectivity of the nanorods is also beneficial for charge transport. The high-dimensional (3D) architecture results in sufficient active sites per the projected electrode surface area and is favorable for efficient mass diffusion during catalysis. A low overpotential of 313 mV is required to drive an OER current density of 10 mA cm^-2 on a simple glassy carbon (GC) working electrode in a 1.0 m KOH aqueous solution.

Urinary F2 -Isoprostanes in Cats with International Renal Interest Society Stage 1-4 Chronic Kidney Disease

BACKGROUND

F₂ -isoprostanes, a biomarker of oxidant injury, increase with advancing chronic kidney disease (CKD) in humans. In cats, the relationship between CKD and oxidative stress is poorly understood.

OBJECTIVES

To determine whether cats with advancing CKD have increasing urinary F₂ -isoprostanes.

ANIMALS

Control cats without evidence of CKD (≥6 years old; n = 11), and cats with IRIS stage 1 (n = 8), 2 (n = 38), 3 (n = 21), and 4 (n = 10) CKD.

METHODS

This was a prospective observational study. Urinary F₂ -isoprostanes (specifically free 15-F_2t -isoprostanes) normalized to urine creatinine (IsoPs) were compared among groups and tested for correlations with blood pressure, proteinuria, serum creatinine concentration, and urine specific gravity. The IsoPs also were compared between cats with and without hypertension or proteinuria, and in cats fed predominantly standard versus renal diets.

RESULTS

Urinary IsoPs were increased, but not significantly, in cats with stage 1 CKD (median 263 pg/mg creatinine; range, 211-380) compared to controls (182 pg/mg; range, 80-348) and decreased significantly from stage 1 through advancing CKD (stage 2, 144 pg/mg; range, 49-608; stage 3, 102 pg/mg; range, 25-158; stage 4, 67 pg/mg; range, 26-117; P < .01). Urinary IsoPs were inversely correlated with serum creatinine (r = -0.66, P < .0001).

CONCLUSION AND CLINICAL IMPORTANCE

Urinary IsoPs are significantly higher in early CKD (stage 1) compared to cats with more advanced CKD. Additional studies are warranted to characterize oxidative stress in cats with stage 1 CKD and determine whether early antioxidant treatments have a protective effect on CKD progression.

Local Anaesthetic Toxicity after Bilateral Thoracic Paravertebral Block in Patients Undergoing Coronary Artery Bypass Surgery

We conducted a small pilot observational study of the effects of bilateral thoracic paravertebral block (BTPB) as an adjunct to perioperative analgesia in coronary artery bypass surgery patients. The initial ropivacaine dose prior to induction of general anaesthesia was 3 mg/kg, which was followed at the end of the surgery by infusion of ropivacaine 0.25% 0.1 ml/kg/hour on each side (e.g. total 35 mg/hour for a 70 kg person). The BTPB did not eliminate the need for supplemental opioids after CABG in the eight patients studied. Moreover, in spite of boluses that were within the manufacturer's recommendation for epidural and major nerve blocks, and an infusion rate that was only slightly higher than what appeared to be safe for epidural infusion, potentially toxic total plasma ropivacaine concentrations were common. We also could not exclude the possibility that the high ropivacaine concentrations were contributing to postoperative mental state changes in the postoperative period. Also, one patient developed local anaesthetic toxicity after the bilateral paravertebral dose. As a result, the study was terminated early after four days. The question of whether paravertebral block confers benefits in cardiac surgery remains unanswered. However, we believe that the bolus dosage and the injection rate we used for BTPB were both too high, and caution other clinicians against the use of these doses. Future studies on the use of BTPB in cardiac surgery patients should include reduced ropivacaine doses injected over longer periods.