Morphology does not matter: WSe2 luminescence nanothermometry unravelled.

Transition metal dichalcogenides, including WSe2, have gained significant attention as promising nanomaterials for various applications due to their unique properties. In this study, we explore the temperature-dependent photoluminescent properties of WSe2 nanomaterials to investigate their potential as luminescent nanothermometers. We compare the performance of WSe2 quantum dots and nanorods synthesized using sonication synthesis and hot injection methods. Our results show a distinct temperature dependence of the photoluminescence, and conventional ratiometric luminescence thermometry demonstrates comparable relative thermal sensitivity (0.68-0.80% K-1) and temperature uncertainty (1.3-1.5 K), irrespective of the morphology of the nanomaterials. By applying multiple linear regression to WSe2 quantum dots, we achieve enhanced thermal sensitivity (30% K-1) and reduced temperature uncertainty (0.1 K), highlighting the potential of WSe2 as a versatile nanothermometer for microfluidics, nanofluidics, and biomedical assays.

Facile Fabrication of High-Performance Thermochromic VO2-Based Films on Si for Application in Phase-Change Devices.

This work reports on an alternative and advantageous procedure to attain VO2-based thermochromic coatings on silicon substrates. It involves the sputtering of vanadium thin films at glancing angles and their subsequent fast annealing in an air atmosphere. By adjusting thickness and porosity of films as well as the thermal treatment parameters, high VO2(M) yields were achieved for 100, 200, and 300 nm thick layers treated at 475 and 550 °C for reaction times below 120 s. Comprehensive structural and compositional characterization by Raman spectroscopy, X-ray diffraction, and scanning-transmission electron microscopies combined with analytical techniques such as electron energy-loss spectroscopy bring to the fore the successful synthesis of VO2(M) + V2O3/V6O13/V2O5 mixtures. Likewise, a 200 nm thick coating consisting exclusively of VO2(M) is also achieved. Conversely, the functional characterization of these samples is addressed by variable temperature spectral reflectance and resistivity measurements. The best results are obtained for the VO2/Si sample with changes in reflectance of 30-65% in the near-infrared at temperatures between 25 and 110 °C. Similarly, it is also proven that the achieved mixtures of vanadium oxides can be advantageous for certain optical applications in specific infrared windows. Finally, the features of the different structural, optical, and electrical hysteresis loops associated with the metal-insulator transition of the VO2/Si sample are disclosed and compared. These remarkable thermochromic performances hereby accomplished highlight the suitability of these VO2-based coatings for applications in a wide range of optical, optoelectronic, and/or electronic smart devices.

Emission properties of Pd-doped CsPbBr3 perovskite nanocrystal: Infrared emission due to the Pd-doping.

Perovskite-type materials have attracted great attention in recent times due to their interesting characteristics, such as their luminescent properties. The good photoluminescence quantum yields as well as the possibility of tuning the emission wavelength has allowed the study of these materials in several applications, such as sensors or LEDs. As sensors, making nanocrystals of these perovskites emitting in the near infrared (NIR) would open the possibility of using these materials in biomedical applications. In the present work, Pd-doped CsPbBr3 perovskite nanocrystals (NCs) were synthesized and characterized. We show here Pd-doped NCs synthesized emit in NIR, at about 875 nm, using a laser emitting at 785 nm as the excitation source. This result is really new and promising, because it opens the possibility of using these nanocrystals in many applications as sensor in the field of nanobiomedicine in the future.

Accuracy of sentinel node mapping in patients with biopsy-proven metastatic axillary lymph nodes and upfront surgery: preliminary results of the Multimodal Targeted Axillary Surgery (MUTAS) trial.

Background: Some studies suggested that the patients included in the Z0011 trial may represent patients with ultrasound-negative axillary nodes and axillary invasion diagnosed by sentinel node (SN) biopsy. Nevertheless, the National Comprehensive Cancer Network (NCCN) guidelines recommend SN mapping if 1 or 2 suspicious lymph nodes are identified on axillary ultrasound (AU). The aim of this preliminary phase of the Multimodal Targeted Axillary Surgery (MUTAS) trial was to establish the accuracy of SN mapping in patients with axillary involvement undergoing upfront surgery. Methods: Between September 2019 and March 2022, we recruited patients with biopsy-proven metastatic axillary nodes and upfront surgery from a single center. We performed SN mapping in these patients before the surgical intervention, which included axillary lymph node dissection. The biopsy-proven metastatic node, SNs and the remaining axillary nodes were excised separately. SN status was considered representative of the status of the remaining axillary nodes. We calculated the sensitivity, specificity, negative predictive value and positive predictive value of the SN, overall and in patients with palpable nodes, in those with non-palpable nodes and an AU leading to diagnosis of axillary involvement, in those with 1 or 2 suspicious nodes on AU, and in patients with a single suspicious node on AU. We evaluated clinical, imaging and pathology features as predictors of the status of the remaining axillary nodes, false-negatives, and false-positives. Results: We included 25 patients in this phase. The false-negative rate of SN mapping was 28% overall, 21.42% for patients with palpable nodes, 36.36% for patients with non-palpable nodes and an AU diagnosis of axillary involvement, 28.75% for those with 1 or 2 suspicious nodes on AU, and 15.38% in patients with a single suspicious node on AU. The negative predictive value was highest in patients with a single suspicious node on AU (75%). The only significant predictive factor was that FN showed a higher Ki67 index score. Conclusions: In this study, SN mapping was not reliable in patients with biopsy-proven metastatic axillary nodes and upfront surgery for any of the subgroups studied. Further research should elucidate the best staging pathways in these patients to avoid premature de-escalation.

Robocasting and Laser Micromachining of Sol-Gel Derived 3D Silica/Gelatin/ß-TCP Scaffolds for Bone Tissue Regeneration.

The design and synthesis of sol-gel silica-based hybrid materials and composites offer significant benefits to obtain innovative biomaterials with controlled porosity at the nanostructure level for applications in bone tissue engineering. In this work, the combination of robocasting with sol-gel ink of suitable viscosity prepared by mixing tetraethoxysilane (TEOS), gelatin and ß-tricalcium phosphate (ß-TCP) allowed for the manufacture of 3D scaffolds consisting of a 3D square mesh of interpenetrating rods, with macropore size of 354.0 ± 17.0 µm, without the use of chemical additives at room temperature. The silica/gelatin/ß-TCP system underwent irreversible gelation, and the resulting gels were also used to fabricate different 3D structures by means of an alternative scaffolding method, involving high-resolution laser micromachining by laser ablation. By this way, 3D scaffolds made of 2 mm thick rectangular prisms presenting a parallel macropore system drilled through the whole thickness and consisting of laser micromachined holes of 350.8 ± 16.6-micrometer diameter, whose centers were spaced 1312.0 ± 23.0 µm, were created. Both sol-gel based 3D scaffold configurations combined compressive strength in the range of 2-3 MPa and the biocompatibility of the hybrid material. In addition, the observed Si, Ca and P biodegradation provided a suitable microenvironment with significant focal adhesion development, maturation and also enhanced in vitro cell growth. In conclusion, this work successfully confirmed the feasibility of both strategies for the fabrication of new sol-gel-based hybrid scaffolds with osteoconductive properties.

Comparison of technical parameters and women's experience between self-compression and standard compression modes in mammography screening: a single-blind randomized clinical trial.

OBJECTIVES: We compared the compression force, breast thickness, and glandular dose, as well as the severity of discomfort and women's experience between the patient-assisted compression (PAC) and standard compression (SC) modes. MATERIALS AND METHODS: We conducted a prospective randomized controlled study at Hospital del Mar in Barcelona, Spain. We included 448 asymptomatic women aged 50 to 69 years old, attending their screening round from December 2017 to December 2019. Mammograms included the two bilateral views. In each woman, one breast was studied with SC and the other with PAC. The mode used in each breast was selected following a randomized list. Compression force, breast thickness, and average glandular dose were obtained for each of the 1792 images. We also recorded the degree of discomfort and women's experience, after mammogram acquisitions, using a predefined survey. RESULTS: Higher compression forces were obtained with PAC than with SC (99.27 N vs 83.25 N, p < 0.001). Breast thickness mode (56.11 mm vs 57.52 mm, p = 0.015) and glandular dose (1.34 mGy vs 1.37 mGy, p = 0.018) were lower in PAC. The discomfort score was slightly higher with PAC (mean 3.94 vs 3.69, p = 0.042), but in the satisfaction survey, more women reported that PAC caused less discomfort. Additionally, 63.2% of women (289/448) preferred PAC. CONCLUSION: PAC achieved higher compression forces without impairing the other technical imaging parameters and enhanced women's experience of screening mammography. We believe there were no clinically significant differences in the severity of discomfort between the two modes. KEY POINTS: • Self-compression allows higher compression forces than the standard compression mode. • Self-compression does not affect technical imaging parameters. • Self-compression improved women's experience of screening mammography when standard compression was used on one breast and self-compression on the other.

Does the patient-assisted compression mode affect the mammography quality? A within-woman randomized controlled trial.

OBJECTIVES: Evaluate the image quality of a mammography screening device using the patient-assisted compression (PAC) compared with the standard compression (SC) mode. METHODS: This prospective within-woman, randomized controlled trial was conducted between September 2017 and December 2019. Participants were asymptomatic women aged 50 to 69 years attending their second or subsequent screening mammography round. By random assignment, one breast underwent the SC and the other breast, the PAC. Image quality was evaluated as perfect, good, moderate, or inadequate (PGMI) on 10 criteria for the craniocaudal (CC) view and 8 criteria for the mediolateral oblique (MLO) view. Pearson's chi-square test, with Yates' correction if pertinent, was performed to compare image quality between compression modes. RESULTS: A total of 444 participants were included (mean [± standard deviation] age, 60 [± 4.9] years). There were no differences in the percentages of PGMI between the PAC and SC modes for the CC view (perfect, 37% [162/444] vs 37% [163/444]; good, 1% [5/444] vs 2% [9/444]; moderate, 62% [277/444] vs 61% [271/444]; inadequate, 0% vs 0.2% [1/444]; p = .88) or for the MLO view (perfect, 53% [237/444] vs 56% [247/444]; good, 22% [99/444] vs 22% [97/444]; moderate, 23% [102/444] vs 22% [98/444]; inadequate, 1% [6/444] vs 0.5% [2/444]; p = .72). No differences were found when we stratified by laterality or when analyzed by PGMI criteria. CONCLUSION: PAC does not seem to impair mammographic image quality. Future research should focus in a daily practice setting. KEY POINTS: No differences were found in the distribution of the PGMI classification, a tool for quality assessment, between patient-assisted compression and standard compression. Similar results were found on stratification of image quality by mammographic view and breast laterality for both types of compression. None of the PGMI criteria had significantly more errors in patient-assisted compression than in standard compression.

Long-Term Risk of Breast Cancer after Diagnosis of Benign Breast Disease by Screening Mammography.

Assessing the long-term risk of breast cancer after diagnosis of benign breast disease by mammography is of utmost importance to design personalised screening strategies. We analysed individual-level data from 778,306 women aged 50-69 years with at least one mammographic screening participation in any of ten breast cancer screening centers in Spain from 1996 to 2015, and followed-up until 2017. We used Poisson regression to compare the rates of incident breast cancer among women with and without benign breast disease. During a median follow-up of 7.6 years, 11,708 (1.5%) women had an incident of breast cancer and 17,827 (2.3%) had a benign breast disease. The risk of breast cancer was 1.77 times higher among women with benign breast disease than among those without (95% CI: 1.61 to 1.95). The relative risk increased to 1.99 among women followed for less than four years, and remained elevated for two decades, with relative risk 1.96 (95% CI: 1.32 to 2.92) for those followed from 12 to 20 years. Benign breast disease is a long-term risk factor for breast cancer. Women with benign breast disease could benefit from closer surveillance and personalized screening strategies.

Mammographic features of benign breast lesions and risk of subsequent breast cancer in women attending breast cancer screening.

OBJECTIVES: To evaluate the mammographic features in women with benign breast disease (BBD) and the risk of subsequent breast cancer according to their mammographic findings. METHODS: We analyzed data from a Spanish cohort of women screened from 1995 to 2015 and followed up until December 2017 (median follow-up, 5.9 years). We included 10,650 women who had both histologically confirmed BBD and mammographic findings. We evaluated proliferative and nonproliferative BBD subtypes, and their mammographic features: architectural distortion, asymmetries, calcifications, masses, and multiple findings. The adjusted hazard ratios (aHR) and 95% confidence intervals (95% CI) for breast cancer were estimated using a Cox proportional hazards model. We plotted the adjusted cumulative incidence curves. RESULTS: Calcifications were more frequent in proliferative disease with atypia (43.9%) than without atypia (36.8%) or nonproliferative disease (22.2%; p value < 0.05). Masses were more frequent in nonproliferative lesions (59.1%) than in proliferative lesions without atypia (35.1%) or with atypia (30.0%; p value < 0.05). Multiple findings and architectural distortion were more likely in proliferative disease (16.1% and 4.7%) than in nonproliferative disease (12.8% and 1.9%). Subsequent breast cancer occurred in 268 (2.5%) women. Compared with women who had masses, the highest risk of subsequent breast cancer was found in those with architectural distortions (aHR, 2.21; 95% CI, 1.16-4.22), followed by those with multiple findings (aHR, 1.89; 95% CI, 1.34-2.66), asymmetries (aHR, 1.66; 95% CI, 0.84-3.28), and calcifications (aHR, 1.60; 95% CI, 1.21-2.12). CONCLUSION: BBD subtypes showed distinct mammographic findings. The risk of subsequent breast cancer was high in those who have shown architectural distortion, multiple findings, asymmetries, and calcifications than in women with masses. KEY POINTS: • The presence of mammographic findings in women attending breast cancer screening helps clinicians to assess women with benign breast disease (BBD). • Calcifications were frequent in BBDs with atypia, which are the ones with a high breast cancer risk, while masses were common in low-risk BBDs. • The excess risk of subsequent breast cancer in women with BBD was higher in those who showed architectural distortion compared to those with masses.

Contrast-enhanced mammography: what the radiologist needs to know.

Contrast-enhanced mammography (CEM) is a combination of standard mammography and iodinated contrast material administration. During the last decade, CEM has found its place in breast imaging protocols: after i.v. administration of iodinated contrast material, low-energy and high-energy images are retrieved in one acquisition using a dual-energy technique, and a recombined image is constructed enabling visualisation of areas of contrast uptake. The increased incorporation of CEM into everyday clinical practice is reflected in the installation of dedicated equipment worldwide, the (commercial) availability of systems from different vendors, the number of CEM examinations performed, and the number of scientific articles published on the subject. It follows that ever more radiologists will be confronted with this technique, and thus be required to keep up to date with the latest developments in the field. Most importantly, radiologists must have sufficient knowledge on how to interpret CEM images and be acquainted with common artefacts and pitfalls. This comprehensive review provides a practical overview of CEM technique, including CEM-guided biopsy; reading, interpretation and structured reporting of CEM images, including the accompanying learning curve, CEM artefacts and interpretation pitfalls; indications for CEM; disadvantages of CEM; and future developments.

Breast density, benign breast disease, and risk of breast cancer over time.

OBJECTIVES: Assessing the combined effect of mammographic density and benign breast disease is of utmost importance to design personalized screening strategies. METHODS: We analyzed individual-level data from 294,943 women aged 50-69 years with at least one mammographic screening participation in any of four areas of the Spanish Breast Cancer Screening Program from 1995 to 2015, and followed up until 2017. We used partly conditional Cox models to assess the association between benign breast disease, breast density, and the risk of breast cancer. RESULTS: During a median follow-up of 8.0 years, 3697 (1.25%) women had a breast cancer diagnosis and 5941 (2.01%) had a benign breast disease. More than half of screened women had scattered fibroglandular density (55.0%). The risk of breast cancer independently increased with the presence of benign breast disease and with the increase in breast density (p for interaction = 0.84). Women with benign breast disease and extremely dense breasts had a threefold elevated risk of breast cancer compared with those with scattered fibroglandular density and without benign breast disease (hazard ratio [HR] = 3.07; 95%CI = 2.01-4.68). Heterogeneous density and benign breast disease was associated with nearly a 2.5 elevated risk (HR = 2.48; 95%CI = 1.66-3.70). Those with extremely dense breast without a benign breast disease had a 2.27 increased risk (95%CI = 2.07-2.49). CONCLUSIONS: Women with benign breast disease had an elevated risk for over 15 years independently of their breast density category. Women with benign breast disease and dense breasts are at high risk for future breast cancer. KEY POINTS: • Benign breast disease and breast density were independently associated with breast cancer. • Women with benign breast disease had an elevated risk for up to 15 years independently of their mammographic density category.

Differences in breast cancer risk after benign breast disease by type of screening diagnosis.

INTRODUCTION: We aimed to assess differences in breast cancer risk across benign breast disease diagnosed at prevalent or incident screens. MATERIALS AND METHODS: We conducted a retrospective cohort study with data from 629,087 women participating in a long-standing population-based breast cancer screening program in Spain. Each benign breast disease was classified as non-proliferative, proliferative without atypia, or proliferative with atypia, and whether it was diagnosed in a prevalent or incident screen. We used partly conditional Cox hazard regression to estimate the adjusted hazard ratios of the risk of breast cancer. RESULTS: Compared with women without benign breast disease, the risk of breast cancer was significantly higher (p-value = 0.005) in women with benign breast disease diagnosed in an incident screen (aHR, 2.67; 95%CI: 2.24-3.19) than in those with benign breast disease diagnosed in a prevalent screen (aHR, 1.87; 95%CI: 1.57-2.24). The highest risk was found in women with a proliferative benign breast disease with atypia (aHR, 4.35; 95%CI: 2.09-9.08, and 3.35; 95%CI: 1.51-7.40 for those diagnosed at incident and prevalent screens, respectively), while the lowest was found in women with non-proliferative benign breast disease (aHR, 2.39; 95%CI: 1.95-2.93, and 1.63; 95%CI: 1.32-2.02 for those diagnosed at incident and prevalent screens, respectively). CONCLUSION: Our study showed that the risk of breast cancer conferred by a benign breast disease differed according to type of screen (prevalent or incident). To our knowledge, this is the first study to analyse the impact of the screening type on benign breast disease prognosis.

Surface States of (100) O-Terminated Diamond: Towards Other 1 × 1:O Reconstruction Models.

Diamond surface properties show a strong dependence on its chemical termination. Hydrogen-terminated and oxygen-terminated diamonds are the most studied terminations with many applications in the electronic and bioelectronic device field. One of the main techniques for the characterization of diamond surface terminations is X-ray photoelectron spectroscopy (XPS). In this sense, the use of angleresolved XPS (ARXPS) experiments allows obtaining depth-dependent information used here to evidence (100)Oterminated diamond surface atomic configuration when fabricated by acid treatment. The results were used to compare the chemistry changes occurring during the oxidation process using a sublayer XPS intensity model. The formation of nondiamond carbon phases at the subsurface and higher oxygen contents were shown to result from the oxygenation treatment. A new (100) 1 × 1:O surface reconstruction model is proposed to explain the XPS quantification results of Oterminated diamond.

The Role of the Interactions at the Tungsten Disulphide Surface in the Stability and Enhanced Thermal Properties of Nanofluids with Application in Solar Thermal Energy.

Transition metal dichalcogenides (TMCs) exhibit unique properties that make them of interest for catalysis, sensing or energy storage applications. However, few studies have been performed into nanofluids based on TMCs for heat transfer applications. In this study, nanofluids based on 2D-WS2 are prepared by liquid phase exfoliation to analyze their potential usage in concentrating solar power plants. Periodic-Density Functional Theory (DFT) calculations were performed to rationalize the success of the exfoliation process. The hydrogen bond interaction between the hydroxyl group from PEG, which acts as a surfactant, and the S atoms of the WS2 surface stabilizes the nanosheets in the fluid. Electron localization function (ELF) analysis is indicative of the stability of the S-H interaction from WS2 with the molecules of surfactant due to the tendency to interact through weak intermolecular forces of van der Waals solids. Moreover, improvements in thermal properties were also found. Isobaric specific heat increased by up to 10% and thermal conductivity improved by up to 37.3%. The high stability of the nanofluids and the thermal improvements were associated with the high surface area of WS2 nanosheets. These results suggest that these nanofluids could be a promising heat transfer fluid in concentrating solar power plants.

Novel WS2-Based Nanofluids for Concentrating Solar Power: Performance Characterization and Molecular-Level Insights.

Nano-colloidal suspensions of nanomaterials in a fluid, nanofluids, are appealing because of their interesting properties related to heat transfer processes. While nanomaterials based on transition metal chalcogenides (TMCs) have been widely studied in catalysis, sensing, and energy storage applications, there are few studies of nanofluids based on TMCs for heat transfer applications. In this study, the preparation and analysis of nanofluids based on 2D-WS2 in a typical heat transfer fluid (HTF) used in concentrating solar power (CSP) plants are reported. Nanofluids prepared using an exfoliation process exhibited well-defined nanosheets and were highly stable. The nanofluids were characterized in terms of properties related to their application in CSP. The presence of WS2 nanosheets did not modify significantly the surface tension, the viscosity, or the isobaric specific heat, but the thermal conductivity was improved by up to 30%. The Ur factor, which characterizes the thermal efficiency of the fluid in the solar collector, shows an enhancement of up to 22% in the nanofluid, demonstrating great promise for CSP applications. The Reynolds number and friction factor of the fluid were not significantly modified by the addition of the nanomaterial to the HTF, which is also positive for practical applications in CSP plants. Ab initio molecular dynamics simulations of the nanoparticle/fluid interface showed an irreversible dissociative adsorption of diphenyl oxide molecules on the WS2 edge, with very low kinetic barrier. The resulting "decoration" of the WS2 edge dramatically affects the nature of the interface interactions and is therefore expected to affect significantly the rheological and transport properties of the nanofluids.

A Solvothermal Synthesis of TiO2 Nanoparticles in a Non-Polar Medium to Prepare Highly Stable Nanofluids with Improved Thermal Properties.

Nanofluids are systems with several interesting heat transfer applications, but it can be a challenge to obtain highly stable suspensions. One way to overcome this challenge is to create the appropriate conditions to disperse the nanomaterial in the fluid. However, when the heat transfer fluid used is a non-polar organic oil, there are complications due to the low polarity of this solvent. Therefore, this study introduces a method to synthesize TiO2 nanoparticles inside a non-polar fluid typically used in heat transfer applications. Nanoparticles produced were characterized for their structural and chemical properties using techniques such as X-ray Diffraction (XRD), Raman spectroscopy, Transmission Electron Microscopy (TEM), Fourier Transform Infrared (FTIR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). The nanofluid showed a high stability, which was analyzed by means of UV-vis spectroscopy and by measuring its particle size and ζ potential. So, this nanofluid will have many possible applications. In this work, the use as heat transfer fluid was tested. In this sense, nanofluid also presented enhanced isobaric specific heat and thermal conductivity values with regard to the base fluid, which led to the heat transfer coefficient increasing by 14.4%. Thus, the nanofluid prepared could be a promising alternative to typical HTFs thanks to its improved thermal properties and high stability resulting from the synthesis procedure.

Revealing at the molecular level the role of the surfactant in the enhancement of the thermal properties of the gold nanofluid system used for concentrating solar power.

A molecular dynamics study based on gold nanofluids performed with and without the presence of tetraoctylammonium halide as a surfactant in a base fluid is presented. The base fluid consisting of a mixture of biphenyl and diphenyl oxide is used in concentrating solar power (CSP) plants. The radial distribution functions (RDFs) and spatial distribution functions (SDFs) were analysed with the temperature. Theoretical results indicate that the surfactant acts as a kind of net around the nanoparticle that plays an active role in enhancing the thermal properties of the gold nanofluid system. A greater lability of the base fluid-surfactant interactions than the base fluid-gold nanoparticle interactions is observed. At lower temperatures, there is an inner layer around the gold nanoparticle with two surfactant molecules close to the metal. At a higher temperature a ratio of gold nanoparticles : diphenyl oxide molecules of 1 : 4 is maintained in the inner layer for the systems with and without the presence of a surfactant. At the highest temperatures, the presence of the surfactant in a second shell impedes the approximation of the fifth diphenyl oxide molecule. Thus, the surfactant affects the macroscopic properties of the gold nanofluid system at the molecular level.

Imaging and pathology features to predict axillary tumor load in breast cancer.

AIM: We investigated if imaging and pathology features could help to identify a high axillary tumor burden (ATB) in breast cancer patients, in order to individualize decisions on axillary lymph node (ALN) dissection (ALND). METHODS: We retrospectively analyzed patients primarily treated with surgery in our unit between 2011 and 2014. We divided the patients in two groups: low ATB (LATB) if ≤ 2 ALN were infiltrated and high ATB (HATB) if > 2 ALN were infiltrated. RESULTS: Data of 105 patients was included in the study. Axillary ultrasound (AUS) features associated with HATB were any sign of ALN infiltration (76 vs 24%, P = 0.027) and > 2 suspicious ALNs (73% vs 27%, P = 0.018); however, when AUS revealed ≤ 2 suspicious ALNs, 39% of these patients had HATB. Any sign of ALN infiltration on magnetic resonance imaging was associated with HATB (48% vs 52%, P = 0.031). Positive preoperative ALN cytology or biopsy was associated with HATB (53% vs 47%, P = 0.008), while p53 positivity (80% vs 20%) and high histological grade (68% vs. 32%) correlated with LATB (P = 0.05 and P = 0.02, respectively). In multivariate analysis, only positive preoperative ALN cytology or biopsy was associated with HATB (P = 0.038). CONCLUSIONS: AUS was useful for detecting HATB but was not as effective in patients with LATB. Proving axillary infiltration with AUS-directed cytology or biopsy is the most effective method to predict HATB.

MoS2/Cu/TiO2 nanoparticles: synthesis, characterization and effect on photocatalytic decomposition of methylene blue in water under visible light.

Photodegradation processes are of great interest in a range of applications, one of which is the photodecomposition of pollutants. For this reason, analysing nanoparticles that improve the efficiency of these processes under solar radiation are very necessary. Thus, in this study, TiO2 was doped with Mo and Cu using low-temperature hydrolysis as the method of synthesis. Pure TiO2 and x%MoS2/Cu/TiO2 nanoparticles were prepared, where x is the theoretical quantity of MoS2 added (0.0%, 1.0%, 5.5%, 10.0%), setting the nominal quantity of Cu at 0.5 wt.%. The samples obtained were characterized by X-ray diffraction, Raman spectroscopy, X-ray electron spectroscopy and UV-Vis spectroscopy in diffuse reflectance mode. The results suggest that the TiO2 structure was doped with the Mo6+ and Cu2+ ions in the position of the Ti4+. The x%MoS2/Cu/TiO2 samples presented lower band gap energy values and greater optical absorption in the visible region than the pure TiO2 sample. Lastly, the photocatalytic activity of the samples was assessed by means of the photodegradation of methylene blue under visible light. The results show that when the quantity of Mo in the co-doped samples increased (x%MoS2/Cu/TiO2) there were significant increases of up to 93% in the photocatalytic activity.

The Role of Surfactants in the Stability of NiO Nanofluids: An Experimental and DFT Study.

This study shows an analysis of the stability of nanofluids based on a eutectic mixture of diphenyl oxide and biphenyl, which is used as a heat transfer fluid (HTF) in concentrating solar energy, and NiO nanoparticles. Two surfactants are used to analyse the stability of the nanofluids: benzalkonium chloride (BAC) and 1-octadecanethiol (ODT). From an experimental perspective, the stability is analysed by means of UV/Vis spectroscopy, particle size measurements through the dynamic light-scattering technique, and ζ-potential measurements. The results show that the stability of the nanofluids improves with the use of BAC. DFT calculations are performed to understand the role played by the surfactants. The interaction of the surfactants with both the fluid and the NiO (100) surface is studied. Quantum theory of atoms in molecules (QTAIM) analysis shows that hydrogen bridge interactions favour the stability of the fluid-surfactant mixture. The more stabilising NiO-surfactant interaction involves the Ni-H interaction of the -SH and -CH3 groups of ODT and BAC. Also, nanofluids with BAC are favoured over those with ODT, which is in agreement with experimental results. The structural and electronic effects of incorporating the surfactant onto the NiO (100) surface are shown by using electron localisation function analysis, the non-covalent interaction index and projected density of states.