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In this study, a tetrafunctional epoxy resin was loaded with 5 wt% of three different types of polyhedral oligomeric silsesquioxane (POSS) compounds, namely, DodecaPhenyl POSS (DPHPOSS), Epoxycyclohexyl POSS (ECPOSS), Glycidyl POSS (GPOSS), and 0.5 wt% of multi-walled carbon nanotubes (CNTs) in order to formulate multifunctional structural nanocomposites tailored for aeronautic and aerospace applications. This work aims to demonstrate how the skillful combination of desired properties, such as good electrical, flame-retardant, mechanical, and thermal properties, is obtainable thanks to the advantages connected with nanoscale incorporations of nanosized CNTs with POSS. The special hydrogen bonding-based intermolecular interactions between the nanofillers have proved to be strategic in imparting multifunctionality to the nanohybrids. All multifunctional formulations are characterized by a Tg centered at values close to 260 °C, fully satisfying structural requirements. Infrared spectroscopy and thermal analysis confirm the presence of a cross-linked structure characterized by a high curing degree of up to 94% and high thermal stability. Tunneling atomic force microscopy (TUNA) allows to detect the map of the electrical pathways at the nanoscale of the multifunctional samples, highlighting a good dispersion of the carbon nanotubes within the epoxy resin. The combined action of POSS with CNTs has allowed to obtain the highest values of self-healing efficiency if compared to those measured for samples containing only POSS in the absence of CNTs. [ABSTRACT FROM AUTHOR]

Hydroxypropyl methylcellulose (HPMC) is blended with methyl gallate (MG) encapsulated with poly(ethylene glycol) (PEG) and then mixed with a liquid electrolyte to prepare a polymer gel electrolyte. The structural and physical properties of prepared polymer gels are analyzed by various analytical instruments. The MG‐PEG‐HPMC hybrid is found to be able for entrapping a large amount of liquid electrolyte and is used to fabricate dye‐sensitized solar cells (DSSCs). This polymer gel electrolyte shows high ionic conductivity (5.43 × 10−4 S cm−1) and good triiodide diffusion coefficient (2.25 × 10−6 cm2 s−1). The resulting DSSCs show an efficiency of 6.96% at a light intensity of 85 mW cm−2. The long‐term stability test reveals that the fabricated DSSCs will be stable even after 500 h. The benefits of incorporating a gel electrolyte into DSSCs are highlighted along with factors affecting the stability of these devices. The use of these bio‐based materials has the potential to make a significant contribution to the widespread exploitation of stable, efficient, and low‐cost dye‐sensitive solar cells. [ABSTRACT FROM AUTHOR]

This work designs and experimentally validates a novel bone-mimicking biomaterial for human cancellous bone vertebral implants. The lattice architecture here proposed consists of a 3D printed titanium auxetic meta-biomaterial, with a complex micro-structure resembling vertebral trabeculae, and exhibiting a negative Poisson's ratio. Through finite element analysis, the work finds the optimal geometrical parameters of the unit cells of the lattice and performs the shape optimization of the trabeculae. This leads to a meta-biomaterial with a Poisson's ratio up to −0.64, and a Young's modulus of 128.3 MPa, close to that of human vertebral cancellous bones, as the experimental validation confirms. The work demonstrates the great potential of additively manufactured hybrid titanium auxetic metamaterials, which can be designed to obtain peculiar mechanical properties that improve bone tissue regeneration while prevent stress-shielding phenomena. [ABSTRACT FROM AUTHOR]

Heart failure is a multifactorial disease that affects an estimated 38 million people worldwide. Current pharmacotherapy of heart failure with reduced ejection fraction (HFrEF) includes combination therapy with angiotensin-converting enzyme inhibitors (ACEi) and β-adrenergic receptor blockers (β-AR blockers), a therapy also used as treatment for non-cardiac conditions. Our knowledge of the molecular changes accompanying treatment with ACEi and β-AR blockers is limited. Here, we applied proteomics and phosphoproteomics approaches to profile the global changes in protein abundance and phosphorylation state in cardiac left ventricles consequent to combination therapy of β-AR blocker and ACE inhibitor in HFrEF and control hearts. The phosphorylation changes induced by treatment were profoundly different for failing than for non-failing hearts. HFrEF was characterized by profound downregulation of mitochondrial proteins coupled with derangement of β-adrenergic and pyruvate dehydrogenase signaling. Upon treatment, phosphorylation changes consequent to HFrEF were reversed. In control hearts, treatment mainly led to downregulation of canonical PKA signaling. The observation of divergent signaling outcomes depending on disease state underscores the importance of evaluating drug effects within the context of the specific conditions present in the recipient heart. [ABSTRACT FROM AUTHOR]

The failing heart is characterized by elevated levels of reactive oxygen species. We have developed an animal model of heart failure induced by chemogenetic production of oxidative stress in the heart using a recombinant adeno-associated virus (AAV9) expressing yeast D-amino acid oxidase (DAAO) targeted to cardiac myocytes. When DAAO-infected animals are fed the DAAO substrate D-alanine, the enzyme generates hydrogen peroxide (H2O2) in the cardiac myocytes, leading to dilated cardiomyopathy. However, the underlying mechanisms of oxidative stress-induced heart failure remain incompletely understood. Therefore, we investigated the effects of chronic oxidative stress on the cardiac transcriptome and metabolome. Rats infected with recombinant cardiotropic AAV9 expressing DAAO or control AAV9 were treated for 7 wk with D-alanine to stimulate chemogenetic H2O2 production by DAAO and generate dilated cardiomyopathy. After hemodynamic assessment, left and right ventricular tissues were processed for RNA sequencing and metabolomic profiling. DAAO-induced dilated cardiomyopathy was characterized by marked changes in the cardiac transcriptome and metabolome both in the left and right ventricle. Downregulated transcripts are related to energy metabolism and mitochondrial function, accompanied by striking alterations in metabolites involved in cardiac energetics, redox homeostasis, and amino acid metabolism. Upregulated transcripts are involved in cytoskeletal organization and extracellular matrix. Finally, we noted increased metabolite levels of antioxidants glutathione and ascorbate. These findings provide evidence that chemogenetic generation of oxidative stress leads to a robust heart failure model with distinct transcriptomic and metabolomic signatures and set the basis for understanding the underlying pathophysiology of chronic oxidative stress in the heart. [ABSTRACT FROM AUTHOR]

In the past few years, the chirality and magnetism of molecules have received notable interest for the development of novel molecular devices. Chiral helicenes combine both these properties, and thus their nanostructuration is the first step toward developing new multifunctional devices. Here, we present a novel strategy to deposit a sub‐monolayer of enantiopure thia[4]helicene radical cations on a pre‐functionalized Au(111) substrate. This approach results in both the paramagnetic character and the chemical structure of these molecules being maintained at the nanoscale, as demonstrated by in‐house characterizations. Furthermore, synchrotron‐based X‐ray natural circular dichroism confirmed that the handedness of the thia[4]helicene is preserved on the surface. [ABSTRACT FROM AUTHOR]

In the past few years, the chirality and magnetism of molecules have received notable interest for the development of novel molecular devices. Chiral helicenes combine both these properties, and thus their nanostructuration is the first step toward developing new multifunctional devices. Here, we present a novel strategy to deposit a sub‐monolayer of enantiopure thia[4]helicene radical cations on a pre‐functionalized Au(111) substrate. This approach results in both the paramagnetic character and the chemical structure of these molecules being maintained at the nanoscale, as demonstrated by in‐house characterizations. Furthermore, synchrotron‐based X‐ray natural circular dichroism confirmed that the handedness of the thia[4]helicene is preserved on the surface. [ABSTRACT FROM AUTHOR]

This work concerns the verification of the self-healing ability of PP-co-HUPy copolymers dispersed in epoxy systems. PP is the acronym for the Poly-PEGMA polymer, and HUPy refers to the HEMA-UPy copolymers based on ureidopyrimidinone (UPy) moieties. In particular, this work aims to verify whether this elastomer characterized by an intrinsic self-healing ability can activate supramolecular interactions among polymer chains of an epoxy resin, as in the elastomer alone. The elastomer includes a class of polyethylene glycol monomethyl ether methacrylate-based copolymers, with different percentages of urea-N-2-amino-4-hydroxy-6-methyl pyrimidine-N'-(hexamethylene-n-carboxyethyl methacrylate) (HEMA-UPy) co-monomers. The self-healing capability of these copolymers based on possible quadruple hydrogen bond interactions between polymer chains has been verified. The formulated epoxy samples did not show self-healing efficiency. This can be attributed to the formation of phase segregation that originates during the curing process of the samples, although the PP-co-HUPy copolymers are completely soluble in the liquid epoxy matrix EP. The morphological investigation highlighted the presence of crystals of PP-co-HUPy copolymers, which are in greater quantity in the sample containing the highest weight percentage (7.8 wt%) of HUPy units. Furthermore, the crystals act as promotors for increasing the curing degree (DC) of the epoxy systems containing HUPy units. DC goes from 91.6% for EP to 96.1% and 95.4% for the samples containing weight percentages of 2.5 and 7.8 wt% of HUPy units, respectively. Dynamic mechanical analysis (DMA) shows storage modulus values for epoxy systems containing PP-co-HUPy units lower than that of the unfilled resin EP. The values of maximum in Tan δ (Tg), representing the temperature at which the glass transition occurs, are 220 for the unfilled resin EP, 228 for the sample containing 2.5 wt% of HEMA-UPy units, and 211 for the sample containing 7.8 wt% of HEMA-UPy units. [ABSTRACT FROM AUTHOR]

The great problem of social chemistry we call politics, is to discover what desires of mankind may be gratified, and what must be suppressed, if the highly complex compound, society, is to avoid decompositionThomas Huxley (1871) In this article, we show that the chaos and urgency induced by the coronavirus disease 2019 (COVID-19) pandemic has led to massive fossil fuel-derived plastic production, largely ignoring recent environmental policies. 1:CAS:528:DC%2BC2sXls1SrurY%3D. 10.1007/s10311-017-0621-7 5 Canning-Clode J, Sepúlved P, Almeida S. Monteiro J (2020) Will COVID-19 containment and treatment measures drive shifts in marine litter pollution? 10.1021/acs.chemmater.0c02008 33 Sarkis J, Cohen MJ, Dewick P, Schröder P. A brave new world: lessons from the COVID-19 pandemic for transitioning to sustainable supply and production. 1:CAS:528:DC%2BC1MXms1agtbg%3D. 10.1007/s10311-019-00859-z 37 Vanapalli KR, Sharma HB, Ranjan VP, Samal B, Bhattacharya J, Dubey BK, Goel S. Challenges and strategies for effective plastic waste management during and post COVID-19 pandemic. [Extracted from the article]

• A Guar Gum-based cost-effective polymer gel electrolyte for dye-sensitized solar cells. • Using this gel electrolyte, DSSCs are fabricated by sandwiching metal-free MK-2 dye. • Guar Gum polymer gel show ionic conductivity. • Device fabricated with Guar Gum gel electrolyte shows maximum power conversion efficiency (4.96%) A Guar Gum-based biopolymer (GG), a characteristic non-ionic polysaccharide extracted from guar beans, is utilized in this work as a cost-effective polymer gel electrolyte towards the fabrication of dye-sensitized solar cells (DSSC). A redox electrolyte is prepared by stirring Guar Gum biopolymer with a known amount of LiI/I 2 , 4- tert -butylpyrdine, 1-methyl-3-propylimidazolium iodide, and polyethylene glycol for 24 hrs. The polymer gel electrolyte is carefully characterized through Fourier transform infrared spectra, UV–visible spectrum, Field-emission scanning electron microscopy and Differential Scanning Calorimetry. Using this polymer gel electrolyte, dye-sensitized solar cells are fabricated by sandwiching metal-free organic MK-2 dye coated TiO 2 photoanode and Pt counter electrode as a photocathode. The photoelectrochemical characterization of the fabricated device shows maximum power conversion efficiency of 4.96% instead of 2.13% obtained with the liquid electrolyte without Guar Gum. The electrolyte containing Guar Gum polymer gel shows ionic conductivity (σ) of 1.46 S [cm]−1 while the liquid electrolyte show 2.44 S [cm]−1. [ABSTRACT FROM AUTHOR]

Many current animal models of heart failure are hampered by intrinsic methodological complexities, while other models yield only a subtle cardiac phenotype even after prolonged in vivo treatments. A new 'chemogenetic' animal model of heart failure reproduces a critical characteristic shared by many disease states that lead to heart failure in humans: an increase in redox stress in the heart. This 'chemogenetic' approach exploits a recombinant yeast enzyme that can be dynamically and specifically activated in vivo to generate the ROS hydrogen peroxide (H2 O2 ) in cardiac myocytes. Redox stress can be rapidly, selectively and reversibly manipulated by chemogenetic generation of ROS in cardiac myocytes, yielding a new model of dilated cardiomyopathy. Treatment of animals with the angiotensin receptor antagonist valsartan promotes recovery of ventricular function and resolution of adverse cardiac remodelling. This mini-review discusses in vivo chemogenetic approaches to manipulate and analyse oxidative stress in the heart. [ABSTRACT FROM AUTHOR]

We previously described a novel "chemogenetic" animal model of heart failure that recapitulates a characteristic feature commonly found in human heart failure: chronic oxidative stress. This heart failure model uses a chemogenetic approach to activate a recombinant yeast Damino acid oxidase in rat hearts in vivo to generate oxidative stress, which then rapidly leads to the development of a dilated cardiomyopathy. Here we apply this new model to drug testing by studying its response to treatment with the angiotensin II (ANG II) receptor blocker valsartan, administered either alone or with the neprilysin inhibitor sacubitril. Echocardiographic and [18F]fluorodeoxyglucose positron emission tomographic imaging revealed that valsartan in the presence or absence of sacubitril reverses the anatomical and metabolic remodeling induced by chronic oxidative stress. Markers of oxidative stress, mitochondrial function, and apoptosis, as well as classical heart failure biomarkers, also normalized following drug treatments despite the persistence of cardiac fibrosis. These findings provide evidence that chemogenetic heart failure is rapidly reversible by drug treatment, setting the stage for the study of novel heart failure therapeutics in this model. The ability of ANG II blockade and neprilysin inhibition to reverse heart failure induced by chronic oxidative stress identifies a central role for cardiac myocyte angiotensin receptors in the pathobiology of cardiac dysfunction caused by oxidative stress. [ABSTRACT FROM AUTHOR]

Calcium storage organelles are common to all eukaryotic organisms and play a pivotal role in calcium signaling and cellular calcium homeostasis. In most organelles, the intraorganellar calcium concentrations rarely exceed micromolar levels. Acidic organelles called acidocalcisomes, which concentrate calcium into dense phases together with polyphosphates, are an exception. These organelles have been identified in diverse organisms, but, to date, only in cells that do not form calcium biominerals. Recently, a compartment storing molar levels of calcium together with phosphorous was discovered in an intracellularly calcifying alga, the coccolithophore Emiliania huxleyi, raising a possible connection between calcium storage organelles and calcite biomineralization. Here we used cryoimaging and cryospectroscopy techniques to investigate the anatomy and chemical composition of calcium storage organelles in their native state and at nanometer-scale resolution. We show that the dense calcium phase inside the calcium storage compartment of the calcifying coccolithophore Pleurochrysis carterae and the calcium phase stored in acidocalcisomes of the noncalcifying alga Chlamydomonas reinhardtii have common features. Our observations suggest that this strategy for concentrating calcium is a widespread trait and has been adapted for coccolith formation. The link we describe between acidocalcisomal calcium storage and calcium storage in coccolithophores implies that our physiological and molecular genetic understanding of acidocalcisomes could have relevance to the calcium pathway underlying coccolithophore calcification, offering a fresh entry point for mechanistic investigations on the adaptability of this process to changing oceanic conditions. [ABSTRACT FROM AUTHOR]

Novel biodegradable composites were prepared using PLA and a nano-hybrid composed of halloysite nanotubes (HNTs) filled with Lysozyme, as antimicrobial. The nano-hybrid was characterized from a structural point of view and the Lysozyme content evaluated by thermogravimetric analysis. Several composites were prepared using ball milling, in dry conditions at ambient temperature, varying the nano-hybrid loading (i.e. 3, 5, 10 wt%). The structural organization and physical properties (thermal, mechanical and barrier to water vapor) ware analyzed and correlated to the nano-hybrid content. Controlled Lysozyme release into saline solution was followed using UV spectrophotometry. The release kinetics was found to be dependent on HNTs-Lysozyme relative fractions. The experimental results were analyzed by a modified Gallagher-Corrigan model. [ABSTRACT FROM AUTHOR]

This study focuses on epoxy hybrid systems prepared by incorporating multi-wall carbon nanotubes (MWCNTs) and graphene nanosheets (GNs) at two fixed filler amounts: below (0.1 wt%) and above (0.5 wt%), with varying MWCNT:GN mix ratios. The hybrid epoxy systems exhibited remarkable electrical performance, attributed to the π–π bond interactions between the multi-wall carbon nanotubes and the graphene layers dispersed in the epoxy resin matrix. The material's properties were characterized through dynamic mechanical and thermal analyses over a wide range of temperatures. In addition to excellent electrical properties, the formulated hybrid systems demonstrated high mechanical performance and thermal stability. Notably, the glass transition temperature of the samples reached 255 °C, and high storage modulus values at elevated temperatures were observed. The hybrid systems also displayed thermal stability up to 360 °C in air. By comparing the mechanical and electrical performance, the formulation can be optimized in terms of the electrical percolation threshold (EPT), electrical conductivity, thermostability, and mechanical parameters. This research provides valuable insights for designing advanced epoxy-based materials with multifunctional properties. [ABSTRACT FROM AUTHOR]

Diabetes and other metabolic conditions characterized by elevated blood glucose constitute important risk factors for cardiovascular disease. Hyperglycemia targets myocardial cells rendering ineffective mechanical properties of the heart, but cellular alterations dictating the progressive deterioration of cardiac function with metabolic disorders remain to be clarified. In the current study, we examined the effects of hyperglycemia on cardiac function and myocyte physiology by employing mice with high blood glucose induced by administration of streptozotocin, a compound toxic to insulin-producing β-cells. We found that hyperglycemia initially delayed the electrical recovery of the heart, whereas cardiac function became defective only after ~2 mo with this condition and gradually worsened with time. Prolonged hyperglycemia was associated with increased chamber dilation, thinning of the left ventricle (LV), and myocyte loss. Cardiomyocytes from hyperglycemic mice exhibited defective Ca2+ transients before the appearance of LV systolic defects. Alterations in Ca2+ transients involved enhanced spontaneous Ca2+ releases from the sarcoplasmic reticulum (SR), reduced cytoplasmic Ca2+ clearance, and declined SR Ca2+ load. These defects have important consequences on myocyte contraction, relaxation, and mechanisms of rate adaptation. Collectively, our data indicate that hyperglycemia alters intracellular Ca2+ homeostasis in cardiomyocytes, hindering contractile activity and contributing to the manifestation of the diabetic cardiomyopathy. [ABSTRACT FROM AUTHOR]

This work investigates the mechanical response of bio-inspired titanium mechanical metamaterials with negative Poisson's ratio evolved from rotating squares unit. The systems were designed and optimized using finite element analysis, with peculiar focus on the shape profile at the interconnection regions of the rotating units. The proposed solution consists of a combined auxetic rotating/chiral architecture with enhanced mechanical and topological properties which exhibits a 3% of global elastic strain of the structure and a Poisson's ratio equal to −0.94. Numerical results are in good agreement with those obtained from experimental tests on a 3D printed Onyx prototype. We also examined the effect on the structural response of the metamaterial subject to off-axis mechanical conditions revealing the strong correlation to the geometrically-related anti -tetrachiral honeycombs. The work confirms the great potential of biologically inspired auxetic metamaterials, which can be designed to obtain tailored mechanical properties while improving the elastic strains capabilities of the system. [Display omitted] • Novel bio-inspired titanium auxetic metamaterials were proposed and investigated. • The designed architecture consists of a hybrid auxetic motif with enhanced mass-to-strength mechanical properties. • The off-axis mechanical behavior of the proposed metamaterials was also analyzed. • The work provides a useful insight for bio-inspired oriented optimization of auxetic mechanical metamaterials. [ABSTRACT FROM AUTHOR]

Studies of myocardial aging are complex and the mechanisms involved in the deterioration of ventricular performance and decreased functional reserve of the old heart remain to be properly defined. We have studied a colony of beagle dogs from 3 to 14 yr of age kept under a highly regulated environment to define the effects of aging on the myocardium. Ventricular, myocardial, and myocyte function, together with anatomical and structural properties of the organ and cardiomyocytes, were evaluated. Ventricular hypertrophy was not observed with aging and the structural composition of the myocardium was modestly affected. Alterations in the myocyte compartment were identified in aged dogs, and these factors negatively interfere with the contractile reserve typical of the young heart. The duration of the action potential is prolonged in old cardiomyocytes contributing to the slower electrical recovery of the myocardium. Also, the remodeled repolarization of cardiomyocytes with aging provides inotropic support to the senescent muscle but compromises its contractile reserve, rendering the old heart ineffective under conditions of high hemodynamic demand. The defects in the electrical and mechanical properties of cardiomyocytes with aging suggest that this cell population is an important determinant of the cardiac senescent phenotype. Collectively, the delayed electrical repolarization of aging cardiomyocytes may be viewed as a critical variable of the aging myopathy and its propensity to evolve into ventricular decompensation under stressful conditions. [ABSTRACT FROM AUTHOR]

The non-Newtonian viscosity behavior of atactic and syndiotactic polystyrenes (aPS and sPS), at temperatures from $$200\,{}^{\circ }\hbox {C}$$ to $$300\,{}^{\circ }\hbox {C}$$ and pressures up to 30 MPa, was studied using the recently proposed Yahsi-Dinc-Tav model, in particular, the Cross-like model. Viscosity data with shear rates of $$0.01\,\hbox {s}^{-1}$$ to $$5000\,\hbox {s}^{-1}$$ were taken from literature at ambient pressure and were reproduced from the Cross-Vogel model at elevated pressures. The viscosities were predicted using the Yahsi-Dinc-Tav model with average absolute deviations of 4.37 % at ambient pressure and 9.63 % at high pressures for aPS and 2.54 % at ambient pressure and 4.79 % at high pressures for sPS. We extended this work to relate the zero shear and the constant shear rate viscosities in terms of the temperature- and pressure-dependent hole fraction using the thermo-occupancy function. The hole fraction ( h) was computed from Simha-Somcynsky hole theory. Analytical relationships of specific density and hole fraction in terms of scaled temperature and pressure were constructed for practical purposes. The effects of tacticity of polystyrenes were discussed in terms of the thermo-occupancy function in detail. In particular, the derivative of the logarithm of the viscosities (viscoholibility) was found to decrease with an increasing hole fraction. [ABSTRACT FROM AUTHOR]

The increased use of bioplastics in the market has led to their presence in municipal solid waste streams alongside traditional fossil-based polymers, particularly low-density polyethylene (LDPE), which bioplastics often end up mixed with. This study aimed to assess the impact of cellulose acetate plasticized with triacetin (CAT) on the mechanical recycling of LDPE. LDPE–CAT blends with varying CAT content (0%, 1%, 5%, 7.5%, and 10% by weight) were prepared by melt extrusion and analyzed using scanning electron microscopy, Fourier-transform infrared spectroscopy, thermal analysis (thermogravimetric and differential scanning calorimetry), dynamic rheological measurements, and tensile tests. The results indicate that the presence of CAT does not significantly affect the chemical, thermal, and rheological properties of LDPE, and the addition of CAT at different levels does not promote LDPE degradation under typical processing conditions. However, the addition of CAT negatively impacts the processability and mechanical behavior of LDPE, resulting in the reduced quality of the recycled material. Thus, the presence of cellulose-based bioplastics in LDPE recycling streams should be avoided, and a specific sorting stream for bioplastics should be established. [ABSTRACT FROM AUTHOR]

The performance of MISTRAL is reported, the soft X-ray transmission microscopy beamline at the ALBA light source (Barcelona, Spain) which is primarily dedicated to cryo soft X-ray tomography (cryo-SXT) for three-dimensional visualization of whole unstained cells at spatial resolutions down to 30 nm (half pitch). Short acquisition times allowing for high-throughput and correlative microscopy studies have promoted cryo-SXT as an emerging cellular imaging tool for structural cell biologists bridging the gap between optical and electron microscopy. In addition, the beamline offers the possibility of imaging magnetic domains in thin magnetic films that are illustrated here with an example. [ABSTRACT FROM AUTHOR]

Polystyrene (PS)/MoS2@oleylamine composites were prepared by solvent blending method. Thermal, mechanical, and tribological properties of the resulting materials were analyzed as function of the filler concentration. SEM characterization for sample morphology as well as infrared spectroscopy and contact angle measurements were carried out in order to characterize the surface properties and the polymer-filler interactions. It was found that despite the poor compatibility between the MoS2@oleylamine nanosheets and the PS matrix, the resulting films present an almost homogeneous dispersion. The PS/MoS2@oleylamine composites showed enhanced thermal stability in comparison with neat PS. In addition, the introduction of MoS2@oleylamine strongly affects the mechanical properties of the PS matrix, reducing both the glass transition temperature and the elastic modulus. Finally, it was found that the MoS2@oleylamine was effective in both reducing friction and increasing wear of PS. POLYM. COMPOS., 36:1124-1134, 2015. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

“Solid state mixing”, such as mechanical milling (MM), represents an ecological and economical alternative to achieve homogeneous dispersion of nano-fillers into biodegradable polymers. The advantage of working at low temperatures, without a solvent and with almost any type of polymer matrix, opens new and unexplored routes for the preparation of advanced functional materials. The use of mechanical milling contains within itself several advantages, including a strong reduction of environmental disposal, the control of the degradation processes associated with high temperature, the compatibilization of immiscible blends and the treatment of waste disposal and recycled materials. The simultaneous formation and dispersion of nanoparticles, the promotion of mechano-chemical reactions and the proper manipulation of thermo-sensitive active molecules such as antimicrobials, oxygen scavengers and antibiotics are other advantages of this process. The aim of the current work is to review the recent literature on the use of MM as a green technique to produce bio-nanocomposites. It is demonstrated how this technology could be considered an interesting option for the fabrication of novel nanostructured materials from environmental friendly resources. [ABSTRACT FROM AUTHOR]

Background--Little is known about the function of inositol 1,4,5-trisphosphate receptors (IP3Rs) in the adult heart experimentally. Moreover, whether these Ca2+ release channels are present and play a critical role in human cardiomyocytes remains to be defined. IP3Rs may be activated after Gαq-protein-coupled receptor stimulation, affecting Ca2+ cycling, enhancing myocyte performance, and potentially favoring an increase in the incidence of arrhythmias. Methods and Results--IP3R function was determined in human left ventricular myocytes, and this analysis was integrated with assays in mouse myocytes to identify the mechanisms by which IP3Rs influence the electric and mechanical properties of the myocardium. We report that IP3Rs are expressed and operative in human left ventricular myocytes. After Gαq-protein-coupled receptor activation, Ca2+ mobilized from the sarcoplasmic reticulum via IP3Rs contributes to the decrease in resting membrane potential, prolongation of the action potential, and occurrence of early afterdepolarizations. Ca2+ transient amplitude and cell shortening are enhanced, and extrasystolic and dysregulated Ca2+ elevations and contractions become apparent. These alterations in the electromechanical behavior of human cardiomyocytes are coupled with increased isometric twitch of the myocardium and arrhythmic events, suggesting that Gαq-protein-coupled receptor activation provides inotropic reserve, which is hampered by electric instability and contractile abnormalities. Additionally, our findings support the notion that increases in Ca2+ load by IP3Rs promote Ca2+ extrusion by forward-mode Na+/Ca2+ exchange, an important mechanism of arrhythmic events. Conclusions--The Gαq-protein/coupled receptor/IP3R axis modulates the electromechanical properties of the human myocardium and its propensity to develop arrhythmias. [ABSTRACT FROM AUTHOR]

The properties of X-ray vacuum-gap waveguides (WGs) with additional periodic structure on one of the reflecting walls are studied. Theoretical considerations, numerical simulations and experimental results confirm that the periodic structure imposes additional conditions on efficient propagation of the electromagnetic field along the WGs. The transmission is maximum for guided modes that possess sufficient phase synchronism with the periodic structure (here called `super-resonances'). The field inside the WGs is essentially given at low incidence angle by the fundamental mode strongly coupled with the corresponding phased-matched mode. Both the simulated and the experimental diffraction patterns show in the far field that propagation takes place essentially only for low incidence angles, confirming the mode filtering properties of the structured X-ray waveguides. [ABSTRACT FROM AUTHOR]

Despite the importance of the effect of pressure on the flow properties of a polymeric material, it is often overlooked also because of the difficulties involved in the experimental measurements. In this study, the effect of pressure on viscosity for an isotactic polypropylene was characterized in both a direct and an indirect method. In particular, a homemade device was adopted to obtain data of viscosity under high pressure and high shear rates. In addition, an indirect method based on the Simha-Somcynsky equation of state was adopted to obtain the dependence of free volume on temperature and pressure on the basis of experimental specific volume measurements; the Doolittle equation was then applied to verify the dependence of viscosity on free volume. The two methods provided similar results, confirming that, at least for polypropylene, the indirect method based on specific volume measurements can be used instead of the more complex direct measurement of the viscosity under pressure. [ABSTRACT FROM AUTHOR]

Three different organo-modified clays have been incorporated by sonication into a high performance epoxy resin before the cross-linking reaction. The X-ray analysis indicated that, depending on the organoclay type, partially exfoliated and partially intercalated composites have been obtained. As shown by the DSC analysis, the clay addition seems to interact with the cross-linking reaction. The incorporation of organoclay into epoxy increased free volume and micro-voids in the samples. Sorption of water in the composite samples resulted higher than that of the pristine resin, whereas the diffusion coefficient is significantly lower. The lower value of diffusion makes the permeability at ambient conditions lower than the pristine resin. The elastic modulus of the composite sample results higher than that of the pristine resin, especially in the temperature region around the glass transition. The presence of organoclay in epoxy matrix decreased the glass transition temperature, whether the nanocomposites were in a dry or wet condition. [ABSTRACT FROM AUTHOR]

Abstract: One of the most attractive characteristics of poly(lactic acid) (PLA) is the fact that, following the international standards for polymer biodegradation, it can be potentially degraded in soil or compost. The potential of this material, however, requires additional investigations in order to understand the PLA behaviour during composting, including the main factors that affect the biodegradation phenomena. In this work, the degradation of PLA was investigated in both distilled water and controlled composting conditions at a temperature of 58 °C. PLA samples with different morphologies were prepared by injection moulding and successive annealing at high temperature. As expected, the crystallinity was found to decrease the PLA degradation rate, but it was also found that the crystallinity affects only partially the first stages of water diffusion in the polymer matrix, whereas it has a significant effect on the final swelling of the samples and on their biodegradation rate. It could therefore be concluded that the denser structure of the initially crystalline sample was more impermeable to the enzymatic attach and to oligomer diffusion. This was also testified by the fact that if the characteristic dimension of the crystalline sample is reduced, degradation rate becomes much faster and close (although still slower) to that of the amorphous sample. [Copyright &y& Elsevier]

Abstract: This paper aims to study the effect of multiwall carbon nanotubes (MWCNTs) on the photo-degradation behavior of polylactic acid (PLA) composites exposed to UV-light. The MWCNT dispersion state within the PLA matrix was analyzed by electrical conductivity measurements. From gel permeation chromatography it was verified that the rate of photo-degradation of PLA/MWCNT composites is lower than that of the unfilled PLA. The surface morphology modifications induced by UV have been analyzed by optical and scanning electron microscopy. Thermal analysis revealed an increase in the polymer crystallinity and a decrease in the degradation temperature during the UV treatment. The mechanical properties (Young's modulus and tensile strength at the yield point) were significantly increased by the addition of MWCNTs. However, the tensile strength and strain to failure slightly decreased with an increase in irradiation time. This complex behavior was attributed to a molecular reorganization in the first period of photo-aging followed by a severe macromolecular chain scission. [Copyright &y& Elsevier]

In this work, syndiotactic polystyrene was injectionmolded withdifferent molding conditions. The morphology distribution inside themolded parts was analyzed by several techniques, including opticalmicroscopy, IR spectroscopy, and X-ray diffraction. The final morphologydistribution was found to be strongly affected by mold temperatureand holding pressures. A peculiar morphology distribution, an alternationof several amorphous and crystalline layers, was found along the samplesthickness. The experimental results were analyzed and discussed bymeans of a software code developed at the University of Salerno. Thesoftware implements a model for crystallinity evolution that is ableto consider the effects of high cooling rates and high pressures.Furthermore, the software is able to predict the orientation evolutionduring the injection molding. On commenting on the differences betweenthe experimental data and the model predictions for crystallinityand orientation, it was possible to gain some insights on the causesof the peculiar morphology distributions inside the molded samples. [ABSTRACT FROM AUTHOR]

Research and development of bio-nanocomposite materials for food applications such as packaging and other food contact surfaces is expected to grow in the next decade with the advent of new polymeric materials and composites with inorganic nano-particles. This article reviews different types of new bio-based materials, such as edible and biodegradable nanocomposite films, their commercial applications as packaging materials, regulations and future trends. Special emphasis is given to the advantages of nanotechnology application in order to improve the mechanical and oxidation stability, the barrier properties, and eventually the biodegradability of conventional polymeric matrices. [Copyright &y& Elsevier]

The crystallization of polymers under pressure has recently attracted particular interest for being a powerful method of obtaining different crystal structures and morphologies. A specific molecular conformation may indeed induce remarkable changes in polymer solvent resistance and mechanical performance. In this work an experimental apparatus was designed and developed to investigate the effects of pressure and cooling rate on polymer samples. The apparatus, based on the confining fluid technique, is able to impose constant external pressures and different cooling rates during the solidification of polymer samples. In its current configuration, the device can reach 1250 bars and a maximum cooling rate of 40 °C/s (measured at 200 °C) with water at 5 °C as a cooling medium. Preliminary results obtained with Syndiotactic Polystyrene confirm that, in addition to thermal history, external pressure is indeed a significant factor for inducing changes in crystalline polymeric structures. The stable orthorhombic β form is favored for specimens solidified under pressure, whereas the overall final crystallinity degree (α and β forms) gradually decreases with both cooling rate and pressure. [ABSTRACT FROM AUTHOR]

Abstract: The technique of high energy ball milling (HEBM) was used to prepare nanocomposites of poly(ε-caprolactone) (PCL) and an organically modified Mg–Al layered double hydroxide. The amount of inorganic material was varied from 0 to 6wt%, and the samples were melted and quenched in ice–water after milling. The molecular weight of PCL decreased and its distribution increased as a consequence of milling. The structural analysis of the milled samples, conducted by X-ray diffraction and infrared absorption techniques, showed that the 12 hydroxydodecanoates organic modifier was still attached to the inorganic lamellae even if a partial delamination of the layered compounds occurred. The mechanical parameters (modulus, stress at yield point, strain at break point and stress at break values) derived from the stress–strain curves, improved in the composite samples containing up to 2.8wt% of inorganic filler, with respect to the pure polymer, in spite of the molecular weight decrease. The thermodynamic diffusion coefficient of water vapor in composite samples was lower than in pure PCL, indicating an improvement of the barrier effect. [Copyright &y& Elsevier]

Biomineralization is the process by which living organisms generate organized mineral crystals. In human cells, this phenomenon culminates with the formation of hydroxyapatite, which is a naturally occurring mineral form of calcium apatite. The mechanism that explains the genesis within the cell and the propagation of the mineral in the extracellular matrix still remains largely unexplained, and its characterization is highly controversial, especially in humans. In fact, up to now, biomineralization core knowledge has been provided by investigations on the advanced phases of this process. In this study, we characterize the contents of calcium depositions in human bone mesenchymal stem cells exposed to an osteogenic cocktail for 4 and 10 days using synchrotron-based cryo-soft-X-ray tomography and cryo-XANES microscopy. The reported results suggest crystalline calcite as a precursor of hydroxyapatite depositions within the cells in the biomineralization process. In particular, both calcite and hydroxyapatite were detected within the cell during the early phase of osteogenic differentiation. This striking finding may redefine most of the biomineralization models published so far, taking into account that they have been formulated using murine samples while studies in human cell lines are still scarce. [ABSTRACT FROM AUTHOR]

Composite foot prostheses are traditionally produced via lamination, a process that grants high structural efficiency. However, it is an expensive and time-consuming process. Production rate and customizability are thus limited. Additive manufacturing of composites can be a potential solution to these limitations. This work presents a tool to design and optimize Continuous Fiber-Reinforced Additively Manufactured (CFRAM) prosthetic feet using beam Finite Element (FE) modeling. This optimization tool was developed for weight minimization and obtaining a CFRAM prosthesis design matching up to three static stiffness parameters. The design variables were defined through parametrizing the geometry of the prosthesis designed and using the composite structure parameters. Thanks to the versatility of the tool, solutions to multiple optimization and design cases were used to assess different design concepts, such as the shape of the prosthesis (C-shape or J-shape). Also, the tool successfully duplicated the stiffness characteristics of an assumed laminated prosthesis. Finally, the sources of inaccuracy associated with the beam FE modeling approach were identified through a comparison with plane stress FE analysis. [ABSTRACT FROM AUTHOR]

Aims In patients with heart failure (HF), concomitant sinus node dysfunction (SND) is an important predictor of mortality, yet its molecular underpinnings are poorly understood. Using proteomics, this study aimed to dissect the protein and phosphorylation remodelling within the sinus node in an animal model of HF with concurrent SND. Methods and results We acquired deep sinus node proteomes and phosphoproteomes in mice with heart failure and SND and report extensive remodelling. Intersecting the measured (phospho)proteome changes with human genomics pharmacovigilance data, highlighted downregulated proteins involved in electrical activity such as the pacemaker ion channel, Hcn4. We confirmed the importance of ion channel downregulation for sinus node physiology using computer modelling. Guided by the proteomics data, we hypothesized that an inflammatory response may drive the electrophysiological remodeling underlying SND in heart failure. In support of this, experimentally induced inflammation downregulated Hcn4 and slowed pacemaking in the isolated sinus node. From the proteomics data we identified proinflammatory cytokine-like protein galectin-3 as a potential target to mitigate the effect. Indeed, in vivo suppression of galectin-3 in the animal model of heart failure prevented SND. Conclusion Collectively, we outline the protein and phosphorylation remodeling of SND in heart failure, we highlight a role for inflammation in electrophysiological remodelling of the sinus node, and we present galectin-3 signalling as a target to ameliorate SND in heart failure. [ABSTRACT FROM AUTHOR]

The knowledge of the mechanical behavior of a 3D-printed material is fundamental for the 3D printing outbreaking technology to be considered for a range of applications. In this framework, the significance, reliability, and accuracy of the information obtained by testing material coupons assumes a pivotal role. The present work focuses on an evaluation of the static mechanical properties and failure modes of a 3D-printed short carbon fiber-reinforced polyamide in relation to the specimen's unique meso-structural morphology and water content. Within the manufacturing limitations of a commercially available printer, specimens of dedicated combinations of geometry and printing patterns were specifically conceived and tested. The specimens' meso-structure morphologies were investigated by micro-computed tomography. The material failure mechanisms were inferred from an analysis of the specimens' fracture surfaces and failure morphologies. The outcomes of the present analysis indicate that each test specimen retained proper mechanical properties, thereby suggesting that they should be accurately designed to deliver representative information of the underlying material beads or of their deposition layout. Suggestions on the adoption of preferred test specimens for evaluating specific material properties were proposed. [ABSTRACT FROM AUTHOR]

Biodegradable block and random copolymers have attracted numerous research interests in different areas, due to their capability to provide a broad range of properties. In this paper, an efficient strategy has been reported for preparing biodegradable PCL-PLA copolymers with improved thermal, mechanical and rheological properties. Two block-copolymers are synthesized by sequential addition of the cyclic esters lactide (L-LA or D,L-LA) and ε-caprolactone (CL) in presence of a dimethyl(salicylaldiminato)aluminium compound. The random copolymer of L-LA and CL was synthetized by using the same catalyst. Chain structure, molar mass, thermal, rheological and mechanical properties are characterized by NMR, SEC, TGA, DSC, Rheometry and DMTA. Experimental results show that by changing the stereochemistry and monomer distribution of the copolymers it is possible to obtain a variety of properties. Promising shape-memory properties are also observed in the di-block copolymers characterized by the co-crystallization of CL and L-LA segments. These materials show great potential to substitute oil-based polymers for packaging, electronics, and medicine applications. [ABSTRACT FROM AUTHOR]

The control of the structural properties of a polymeric material at the micro and nano-metrical scale is strategic to obtaining parts with high performance, durability and free from sudden failures. The characteristic skin-core morphology of injection molded samples is intimately linked to the complex shear flow, pressure and temperature evolutions experienced by the polymer chains during processing. An accurate analysis of this morphology can allow for the assessment of the quality and confidence of the process. Non-symmetric mold temperature conditions are imposed to produce complex morphologies in polypropylene parts. Morphological and micromechanical characterizations of the samples are used to quantify the effects of the processing conditions on the part performance. Asymmetric distribution of temperatures determines asymmetric distribution of both morphology and mechanical properties. The inhomogeneity degree depends on the time that one side of the cavity experiences high temperatures. The spherulites, which cover the thickest of the parts obtained with high temperatures at one cavity side, show smaller values of elastic modulus than the fibrils. When the polymer molecules experience high temperatures for long periods, the solid-diffusion and the partial melting and recrystallization phenomena determine a better structuring of the molecules with a parallel increase of the elastic modulus. [ABSTRACT FROM AUTHOR]

Nowadays, continuous development of soft-electronics and wearable devices opens to the development needs of stretchable and flexible materials able to interface with the human body. In this scenario, biopolymers are particularly intriguing materials given their biocompatibility and biodegradability. For the application in this specific field the material requires several properties such as biological and mechanical performance and thermal stability. In this study, membranes able to fulfill some of these requirements are described. The electrospun membranes, composed of a blend of polycaprolactone (PCL) and gelatin (GN), have been produced in various configurations. The results show how blend or coaxial systems have different effects on both the interactions between the polymers and their thermal and mechanical properties. An important result of the chosen experimental conditions is the narrow dimensional distribution of the nanofiber diameters constituting the electrospun membranes. Thermal and mechanical tests evidenced that, by properly choosing the material composition and the method of the electrospinning process, membranes capable of withstanding high strain values before the failure can be obtained. In particular, optimizing the electrospinning process and using a blend PCL/GN with a mass ratio of 80/20, it is possible to increase the thermal stability up to 310 °C and confer to the sample the ability to reach a percentage of strain up to 350%. [ABSTRACT FROM AUTHOR]

In this paper, an alternative curing strategy, based on the application of an electric field, is proposed to harden nano-filled multifunctional resins. The resin is obtained through the dispersion of carbon nanotubes, which act as nanometric heater elements in the epoxy matrix. The electro-curing is activated by applying an external electric voltage, which allows tunable cross-linking within the epoxy matrix entrapped between the nanotubes. The electro-curing method allows reaching higher curing degrees with respect to the conventional ones and, consequently, higher glass transition temperatures. This is a direct consequence of the fact that the curing reactions start directly in the regions at the interphase between carbon nanotubes, acting as heater nano-filaments, and the polymeric matrix. The proposed method is able to give composites better properties, making the curing process fast and energy-saving. [ABSTRACT FROM AUTHOR]

Poly-3-(9H-carbazol-9-yl)propylmethacrylate (pCMA) is synthesized as a polymer gel electrolyte and employed in the fabrication of dye-sensitized solar cells (DSSC). The pCMA was characterized by various analytical techniques to examine its structural and thermal properties. The photovoltaic and electrochemical effects of this electrolyte in DSSCs were investigated. From the results, it was found that DSSCs assembled with pCMA-PGE is an efficient electrolyte, which yields an open-circuit voltage 545 mV and current density 10 mA for a cell of area 0.25 cm2. pCMA-PGE device shows better performance (η = 2.2%), and it also performs as a good host polymer matrix for redox couple in the electrolyte. [ABSTRACT FROM AUTHOR]

Full control of magnetic properties in exchange coupled systems requires a good understanding of 3D magnetic configuration with lateral and in-depth resolution. Here we show results from a soft X-ray tomographic reconstruction which allow determining, solely from the experimental data, a detailed description of the vector magnetic configuration of a ferrimagnetic Gd12Co88/Nd17Co83/Gd24Co76 trilayer with engineered competing anisotropy, exchange and magnetostatic interactions at different depths. The trilayer displays chevron patterns with a distorted closure structure. Near the top Gd24Co76 layer, local exchange springs with out-of-plane magnetization reversal, quasi-domains with ripple-like patterns and magnetic vortices and antivortices across the thickness are observed. The detailed analysis of the magnetic tomogram shows that the effective strength of the exchange spring at the NdCo/GdCo interface can be finely tuned by GdxCo1-x composition and anisotropy (determined by sample fabrication) and in-plane stripe orientation (adjustable), demonstrating the suitability of 3D magnetic visualization techniques in magnetic engineering research. Full control of magnetic properties in exchange coupled multilayers requires a good understanding of 3D magnetic configuration. Here, soft x-ray magnetic tomography is performed to obtain, solely from experimental data, the vector magnetic configuration of a ferrimagnetic trilayer with engineered competing exchange/magnetostatic interactions at different depths. [ABSTRACT FROM AUTHOR]

Sacubitril/Valsartan, an angiotensin receptor-neprilysin inhibitor (ARNi), is clinically effective in the treatment of patients with HFrEF. Despite the positive results obtained in clinical trials, the mechanisms whereby Sac/Val directly modulates cardiac function are incompletely understood. In this study, we tested whether Sac/Val may prevent cardiac dysfunction induced by oxidative stress in a novel chemogenetic model of heart failure. We exploited a D-amino acid oxidase (DAAO) cloned from yeast that catalyzes the oxidation of D-amino acids to the corresponding keto acid plus hydrogen peroxide (H2O2). Because most mammalian cells use only L-amino acids, the DAAO enzyme remains inactive in transfected cardiac myocytes until D-amino acids are added. This approach is called "chemogenetics". We cloned a novel recombinant AAV9 construct expressing DAAO and infected adult rats with the DAAO-AAV9 or control AAV9 virus via tail vein injection. Four weeks later we provided D-alanine (1 M) in the drinking water of rats infected with DAAO-AAV9 (n=8) or control AAV9 (n=10), and performed weekly echocardiograms read by a blinded observer.Echocardiography showed severe cardiac dysfunction in DAAO-infected rats compared to animals infected with control AAV9 virus: the EF fell from 73 to 43% (p<0.001). We then tested whether treatment of Sac/Val might prevent the cardiac dysfunction observed in DAAO rats. Animals were injected with control (n=4) or DAAO-AAV9 (n=12); after four weeks, a subgroup of DAAO infected rats was treated daily by gavage with 68 mg/kg Sac/Val (n=5) or 31 mg/kg Valsartan (n=4) or vehicle (water; n=3). Five days after starting drug treatments, the animals' drinking water was supplemented with D-alanine; drug treatments were continued, and echocardiograms were performed weekly for 4 weeks. DAAO-infected rats again showed a markedly reduced ejection fraction compared to control (from 72 to 41%, p=0.005). However, treatment with Sac/Val prevented the decline in EF seen with vehicle-treated DAAO rats (70% for Sac/Val-treated animals, p=0.002). Treatment with valsartan had an intermediate phenotype (EF=62%, p= 0.043). These findings suggest that Sac/Val prevents the development of chemogenetic cardiomyopathy induced by oxidative stress [ABSTRACT FROM AUTHOR]

[Display omitted] • A green high-temperature and pressure-assisted hydrothermal method is used to prepare photoactive g-C 3 N 4 doped TiO 2. • The g-C 3 N 4 doped TiO 2 and pure g-C 3 N 4 , TiO 2 (T400) were designed and utilized as photoanode materials for dye-sensitized solar cells. • An optimal efficiency of 9% was attained for the g-C 3 N 4 doped TiO 2 , outperforming the anatase sintered TiO 2. • A thin layer of g-C 3 N 4 on the TiO 2 surface effectively reduces electron recombination and contributes significantly to the efficiency enhancement. This article explores the potential of a novel photoanode material, g-C 3 N 4 doped TiO 2 in improving the photon-to-current conversion efficiency of standard dye-sensitized solar cells. The hybrid nanocomposite photoanode shows a higher light conversion efficiency compared to traditional sintered anatase TiO 2 (T400). A novel solvothermal method is used to synthesize and assess the performance of the g-C 3 N 4 doped TiO 2 as a photoanode for electron collection in dye-sensitized solar cells (DSSC). The results indicate an optimal efficiency of 9% for the fabricated DSSC with g–C 3 N 4 /TiO 2 (g-TO) nanocomposite photoanode, surpassing the efficiency of DSSCs with TiO 2 (T400) as a photoanode. The research presented here highlights that g-C 3 N 4 /TiO 2 exhibits outstanding properties and holds great potential for implementation in photo energy conversion devices for practical applications. [ABSTRACT FROM AUTHOR]

High glucose-induced endothelial dysfunction is the early event that initiates diabetes-induced vascular disease. Here we employed Cryo Soft X-ray Tomography to obtain three-dimensional maps of high d-glucose-treated endothelial cells and their controls at nanometric spatial resolution. We then correlated ultrastructural differences with metabolic rewiring. While the total mitochondrial mass does not change, high d-glucose promotes mitochondrial fragmentation, as confirmed by the modulation of fission–fusion markers, and dysfunction, as demonstrated by the drop of membrane potential, the decreased oxygen consumption and the increased production of reactive oxygen species. The 3D ultrastructural analysis also indicates the accumulation of lipid droplets in cells cultured in high d-glucose. Indeed, because of the decrease of fatty acid β-oxidation induced by high d-glucose concentration, triglycerides are esterified into fatty acids and then stored into lipid droplets. We propose that the increase of lipid droplets represents an adaptive mechanism to cope with the overload of glucose and associated oxidative stress and metabolic dysregulation. [ABSTRACT FROM AUTHOR]