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Nanomaterials can be game-changers in the arena of sustainable energy production because they may enable highly efficient thermoelectric energy conversion and harvesting. For this purpose, doped thin film oxides have been proven to be promising systems for achieving high thermoelectric performances. In this work, the design, realization, and experimental investigation of the thermoelectric properties exhibited by a set of five Al:ZnO thin films with thicknesses of 300 nm and Al doping levels ranging from 2 to 8 at.% are described. Using a multi-technique approach, the main structural and morphological features of the grown thin films are addressed, as well as the electrical and thermoelectrical transport properties. The results show that the samples exhibited a Seebeck coefficient absolute value in the range of 22–33 μV/K, assuming their maximum doping level was 8 at.%, while the samples' resistivity was decreased below 2 × 10−3 Ohm·cm with a doping level of 3 at.%. The findings shine light on the perspectives of the applications of the metal ZnO thin film technology for thermoelectrics. [ABSTRACT FROM AUTHOR]

Simple Summary: In this study, we confirm the bactericidal effect of a special anodizing method, based on TiO2 nanoparticles (DURALTI®) deposited on aluminum disks with different roughness and subjected to two sanitizing treatments, and, consequently, performing a time-course evaluation against both Gram-negative and Gram-positive bacteria. DURALTI® coating already confirmed its ability to induce a 4-logarithmic decrease (from 106 to 102 CFU/mL) after 6 h. Once each sanitizing treatment was applied, an overall bacterial inhibition occurred in a time ranging from 15′′ to 1′. Aluminum is the second most widely used metal worldwide. It is present as an additive in cosmetics, pharmaceuticals, food, and food contact materials (FCM). In this study, we confirm the bactericidal effect of a special anodizing method, based on TiO2 nanoparticles (DURALTI®) deposited on aluminum disks with different roughness and subjected to two sanitizing treatments: UV and alcohol 70%. Consequently, we perform a time-course evaluation against both Gram-negative and Gram-positive bacteria to better frame the time required to achieve the best result. Approximately 106 CFU/mL of Escherichia coli ATCC 25922; Salmonella Typhimurium ATCC 1402; Yersinia enterocolitica ATCC 9610; Pseudomonas aeruginosa ATCC 27588; Staphylococcus aureus ATCC 6538; Enterococcus faecalis ATCC 29212; Bacillus cereus ATCC 14579 and Listeria monocytogenes NCTT 10888 were inoculated onto each aluminum surface and challenged with UV and alcohol 70% at 0, 15", 30", 1′, 5′, 15′, 30′, 1, 2, 4 and 6 h. DURALTI® coating already confirmed its ability to induce a 4-logarithmic decrease (from 106 to 102 CFU/mL) after 6 h. Once each sanitizing treatment was applied, an overall bacterial inhibition occurred in a time ranging from 15′′ to 1′. The results are innovative in terms of preventing microbial adhesion and growth in the food industry. [ABSTRACT FROM AUTHOR]

The piezoelectric response of ZnO thin films in heterostructure-based devices is strictly related to their structure and morphology. We optimize the fabrication of piezoelectric ZnO to reduce its surface roughness, improving the crystalline quality, taking into consideration the role of the metal electrode underneath. The role of thermal treatments, as well as sputtering gas composition, is investigated by means of atomic force microscopy and x-ray diffraction. The results show an optimal reduction in surface roughness and at the same time a good crystalline quality when 75% O2 is introduced in the sputtering gas and deposition is performed between room temperature and 573 K. Subsequent annealing at 773 K further improves the film quality. The introduction of Ti or Pt as bottom electrode maintains a good surface and crystalline quality. By means of piezoelectric force microscope, we prove a piezoelectric response of the film in accordance with the literature, in spite of the low ZnO thickness and the reduced grain size, with a unipolar orientation and homogenous displacement when deposited on Ti electrode. [ABSTRACT FROM AUTHOR]

One of the most-used food contact materials is stainless steel (AISI 304L or AISI 316L), owing to its high mechanical strength, cleanability, and corrosion resistance. However, due to the presence of minimal crevices, stainless-steel is subject to microbial contamination with consequent significant reverb on health and industry costs due to the lack of effective reliability of sanitizing agents and procedures. In this study, we evaluated the noncytotoxic effect of an amorphous SiOxCyHz coating deposited on stainless-steel disks and performed a time-course evaluation for four Gram-negative bacteria and four Gram-positive bacteria. A low cytotoxicity of the SiOxCyHz coating was observed; moreover, except for some samples, a five-logarithm decrease was visible after 1 h on coated surfaces without any sanitizing treatment and inoculated with Gram-negative and Gram-positive bacteria. Conversely, a complete bacterial removal was observed after 30 s−1 min application of alcohol and already after 15 s under UVC irradiation against both bacterial groups. Moreover, coating deposition changed the wetting behaviors of treated samples, with contact angles increasing from 90.25° to 113.73°, realizing a transformation from hydrophilicity to hydrophobicity, with tremendous repercussions in various technological applications, including the food industry. [ABSTRACT FROM AUTHOR]

Atomic force microscopy is an extremely versatile technique, featuring atomic-scale imaging resolution, and also offering the possibility to probe interaction forces down to few pN. Recently, this technique has been specialized to study the interaction between single living cells, one on the substrate, and a second being adhered on the cantilever. Cell–cell force spectroscopy offers a unique tool to investigate in fine detail intra-cellular interactions, and it holds great promise to elucidate elusive phenomena in physiology and pathology. Here we present a systematic study of the effect of the main measurement parameters on cell–cell curves, showing the importance of controlling the experimental conditions. Moreover, a simple theoretical interpretation is proposed, based on the number of contacts formed between the two interacting cells. The results show that single cell–cell force spectroscopy experiments carry a wealth of information that can be exploited to understand the inner dynamics of the interaction of living cells at the molecular level. [ABSTRACT FROM AUTHOR]

Stainless steel, widely present in the food industry, is frequently exposed to bacterial colonization with possible consequences on consumers' health. 288 stainless steel disks with different roughness (0.25, 0.5 and 1 μm) were challenged with four Gram-negative (Escherichia coli ATCC 25922, Salmonella typhimurium ATCC 1402, Yersinia enterocolitica ATCC 9610 and Pseudomonas aeruginosa ATCC 27588) and four Gram-positive bacteria (Staphylococcus aureus ATCC 6538, Enterococcus faecalis ATCC 29212, Bacillus cereus ATCC 14579 and Listeria monocytogenes NCTT 10888) and underwent three different sanitizing treatments (UVC, alcohol 70% v/v and Gold lotion). Moreover, the same procedure was carried out onto the same surfaces after a nanotechnological surface coating (nanoXHAM® D). A significant bactericidal effect was exerted by all of the sanitizing treatments against all bacterial strains regardless of roughness and surface coating. The nanoXHAM® D coating itself induced an overall bactericidal effect as well as in synergy with all sanitizing treatments regardless of roughness. Stainless steel surface roughness is poorly correlated with bacterial adhesion and only sanitizing treatments can exert significant bactericidal effects. Most of sanitizing treatments are toxic and corrosive causing the onset of crevices that are able to facilitate bacterial nesting and growth. This nanotechnological coating can reduce surface adhesion with consequent reduction of bacterial adhesion, nesting, and growth. [ABSTRACT FROM AUTHOR]

Simple Summary: We firstly described the bacteriostatic activity of aluminum surfaces with three different large-scale roughness against both Gram-negative and Gram-positive bacteria, and the bactericidal activity of three different sanitizing treatments performed on each roughness. Then, we described the bactericidal activity of the same surfaces treated with a special anodizing based on titanium oxide regardless of sanitizing agents and roughness. One of the main concerns of the food industry is microbial adhesion to food contact surfaces and consequent contamination. We evaluated the potential bacteriostatic/bactericidal efficacy of aluminum surfaces with different large-scale roughness (0.25, 0.5 and 1 μm) before and after the surface treatment with a special anodizing based on titanium oxide nanotechnology (DURALTI®) and after 3 different sanitizing treatments, e.g., UV, alcohol and a natural product named Gold lotion. Four Gram-negative (Escherichia coli ATCC 25922, Salmonella typhimurium ATCC 1402, Yersinia enterocolitica ATCC 9610 and Pseudomonas aeruginosa ATCC 27588) and four Gram-positive (Staphylococcus aureus ATCC 6538, Enterococcus faecalis ATCC 29212, Bacillus cereus ATCC 14579 and Listeria monocytogenes NCTT 10888) bacteria were screened. As far as concerns aluminum surfaces without nanotechnology surface treatment, an overall bacteriostatic effect was observed for all strains with respect to the initial inoculum that was 106 CFU/mL. Conversely, an overall bactericidal effect was observed both for Gram-negative and -positive bacteria on DURALTI®-treated aluminum disks, regardless of roughness and sanitizing treatment. These results are innovative in terms of the great potential of the antibacterial activity of nanotechnologically treated food contact surfaces and their combination with some sanitizing agents that might be exploited in the food industry. [ABSTRACT FROM AUTHOR]

Glioblastoma multiforme (GBM) is the most aggressive malignant tumor of the central nervous system, with poor survival in both treated and untreated patients. Recent studies began to explain the molecular pathway, comprising the dynamic structural and mechanical changes involved in GBM. In this context, some studies showed that the human glioblastoma cells release high levels of glutamate, which regulates the proliferation and survival of neuronal progenitor cells. Considering that cancer cells possess properties in common with neural progenitor cells, it is likely that the functions of glutamate receptors may affect the growth of cancer cells and, therefore, open the road to new and more targeted therapies. [ABSTRACT FROM AUTHOR]