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In this article the influence of mechanical activation on sintering process of magnesium-titanate and barium-zinc-titanate ceramics has been investigated. Both nonactivated and mixtures treated in planetary ball mill for 80 minutes were sintered at 1100ºC and 1300ºC. The influence of mechanical activation on phase composition and crystal structure has been analyzed by XRD, while the effect of activation and sintering process on microstructure was investigated by scanning electron microscopy. It has been established that temperature of 1100ºC was to low to induce final sintering stage for both systems. Moreover, we concluded that barium-zinc-titanate ceramics exhibited better sinterability than magnesium-titanate ceramics.

In this study it was investigated influence of temperature and frequency on permeability, coercivity and power loses of Fe81B13Si4C2 amorphous alloy. Magnetic permeability measurements performed in nonisothermal and isothermal conditions was confirmed that efficient structural relaxation was occurred at temperature of 663 K. This process was performed in two steps, the first one is kinetic and the second one is diffuse. Activation energies of these processes are: Ea1 = 52.02 kJ/mol for kinetic and Ea2 = 106.9 kJ/mol for diffuse. It was shown that after annealing at 663 K coercivity decrease about 30% and therefore substantial reduction in power loses was attained. Investigated amorphous alloy satisfied the criteria for signal processing devices that work in mean frequency domain.

This paper contains the results of a research focused on the determination of the influence of an implant inclination on the strain state throughout the acrylic block with implant. The aim of the presented research is to qualitatively determine the regions with the greatest strain fields on the models. The finite element models of implant and acrylic block are developed for predefined implant inclinations in order to analyze the influence of implant inclination on deformations on the outer surface of acrylic block. The comparative contour plots of stress and strain state of analyzed models, as well as the comparative diagrams with obtained results, are presented. The conclusions about the inclination angle which leads to the higher strains in the block-implant are explained. Obtained results could be applied for the planning of future experimental studies which could utilize this and similar models to determine their load transfer characteristics, and could be included in the planning of dental implant position, and prediction of successful dental therapy. [ABSTRACT FROM AUTHOR]

17β-Estradiol (E2) crucially affects several processes in the hippocampus of both sexes. E2 acts upon estradiol receptors ERα and ERβ, influencing target gene expression and/or modulates intracellular signaling cascades. Another potent modulator of hippocampal function is nucleoside adenosine, the final product of ectonucleotidase cascade, enzymes which hydrolyze extracellular ATP to adenosine. The last and rate-limiting step of the hydrolysis is catalyzed by membrane-bound ecto-5′-nucleotidase (eN). Previous findings obtained on adenosine metabolism in brain suggest that eN may be modulated by ovarian steroids. Therefore, the present study reports that the activity and protein abundance of membrane-bound eN fluctuates across the estrus cycle in the hippocampal synaptosomes of female rats. Further, we analyzed the role of E2 and its intracellular receptors on the expression of eN in ovariectomized females. We found that E2 upregulated eN activity and protein abundance in the hippocampal synaptosomes. Application of nonspecific ER antagonist, ICI 182,780 and selective ERα and ERβ agonists, PPT and DPN, respectively, demonstrated the involvement of both receptor subtypes in observed actions. Selective ERα receptor agonist, PPT, induced upregulation of both the protein level and activity of eN, while application of selective ERβ receptor agonist, DPN, increased only the activity of eN. In both cases, E2 entered into the intracellular compartment and activated ER(s), which was demonstrated by membrane impermeable E2–BSA conjugate. Together these results imply that E2-induced effects on connectivity and functional properties of the hippocampal synapses may be in part mediated through observed effect on eN. [ABSTRACT FROM AUTHOR]

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Powder mixture of 50 mass % of barium titanate (BaTiO3) and 50 mass % of iron (Fe) was prepared by solid-state reaction technique, i.e. ball milled in air for 60 min, 80 min, 100 min, 120 min and 150 min. During mechanochemical activation it was observed the iron powder transitsion to iron oxides. Depending on the activation time the content of iron oxides FeO, Fe2O3 and Fe3O4 varies. Simultaneously, with the content change of the activated system, magnetic properties change as well. The XRD analysis of milled samples shown that as the activation time increase, the iron oxide percentage increases to, whereby the percentage of BaTiO3 in a total sample mass decreases. The percentage of iron oxides and BaTiO3 in annealed samples changes depending on annealing temperature. The thermomagnetic measurements performed by Faraday method shown that the powder mixture milled for 100 minutes exhibit maximum magnetization prior to annealing. The increase of magnetization maximum was observed after annealing at 540 °C with all milled samples, and at room temperature it has enhancement from 10 % to 22 % depending on the activation time. The samples milled for 100 min and 150 min and then sintered at 1200 °C exhibit magnetoelectric properties [ABSTRACT FROM AUTHOR]

This paper presents a study on structural changes occurring in a rapidly quenched metastable AlSilOMg alloy during heating cycles within the temperature range from room temperature to 800 K. Measurement of electrical resistivity of a ribbon showed that structural stabilization takes place at temperatures ranging from 450 K to 650 K. The isotherms of the electrical resistivity measured at temperatures 473 K, 483 K and 498 K revealed two stages of structural stabilization i.e. a kinetic process and diffusion process. Measurement of the thermoelectromotive force of the thermocouple made from the investigated alloy and a copper conductor by a mechanical joining was used to determine relative changes in the electron density of states of the quenched sample after successive heat treatments. The same alloy sample was subjected to successive heat treatments at temperatures up to 503 K, 643 K, 683 K and 763 K. The change in the thermopower suggested that each heating was followed by an increase in free electron density in the alloy. Therefore, the abrupt decline in electrical resistivity was induced by an increase in both the mean free electron path and free electron density during the thermal stabilization of the structure. [ABSTRACT FROM AUTHOR]

In this article, the advantages of combined sintering in comparison with the conventional one, of mechanically activated magnesium titanate ceramic were investigated. The stoichiometric mixtures of MgO and TiO2 were mechano-chemically activated for 0, 10, 40, 80 and 160 minutes by ball milling and then isostatically pressed (CIP) to form green bodies. Conventional sintering was realized by heating up to 1400 °C and hold for 30 minutes in air atmosphere. Resulting ceramic samples with closed porosity were post-sintered by pressure assisted technique Hot Isostatic Pressing (HIP) at 1280 oC/3h in argon atmosphere with a pressure of 200 MPa. The best results were observed in the case of samples postsintered by HIP, when single-phase MgTiO3 samples with relative density of 96% were prepared. [ABSTRACT FROM AUTHOR]

In this study, properties of soft-magnetic manganese zinc ferrite manufactured by powder injection moulding -- PIM technology were presented. A powder consisting of Mn1-xZnxFe2O4 and a small amount of hematite α-Fe2O3 was mixed with an organic binder (wax and thermoplastic) to form ferrite feedstock. Then, injection moulded toroidal samples were solvent, thermally debinded prior to sintering in air atmosphere. Magnetic properties were investigated by thermomagnetic measurements (Faraday balance μ-T curve) and a hysteresis graph (B-H curve at different frequencies up to 1 kHz). The Curie temperature was TC ≈ 390 K for the green sample but after heating up to 740 K, TC increased up to about 570 K. The high increase in normalized magnetic permeability of about 700 % was observed due to the melting and burning of the binder. The hysteresis loop of sintered MnZn ferrite toroidal cores had an R-shape with saturation of 0.44 T and the remanence ratio of 0.49. The low value of coercivity (only 0.047 kA/m) was related to the presence of α-Fe2O3 crystalline phase as well as optimum density attained (ρ ≈ 4800 kg/m³) i.e. the low porosity observed. The relative magnetic permeability attained μr ≈ 2 · 10³ and core power losses Ps ≈ 21 W/kg for the sintered sample (at 1000 Hz; 0.39 T) are in agreement with the MnZn ferrite commercial samples prepared by standard ceramic route. [ABSTRACT FROM AUTHOR]

In this study, the evolution of the nanostructure on dc Joule heated Fe72Al5Ga2P11C6B4 metallic glass ribbons have been investigated. Heating power per square area (PS) was ranging between 0.8 to 7.1 W/cm² in order to get various stages of relaxation or nanocrystallization. The crystallization starts after applying PS ≈ 4.35 W/cm² and the sample consist of residual amorphous matrix, a magnetic crystalline component and also a non-magnetic crystalline component (relative abundance of Fe in the crystalline phase is about 35 %). XRD measurements show that crystalline samples after current annealing consist of Fe3B, FeC, FeP and Fe3P compounds. On TEM micrograph a broad distribution of shapes and sizes is noticed, the latter range from about 60 to 350 nm, increasing by applied heating power. The decrease of the electrical resistivity after each current annealing treatment is rather small in comparison with other Fe-based amorphous alloys (only about 1.5 % for the highest PS). Partial nanocrystallization leads to increase of coercive field (from HC ≈ 7 A/m in the amorphous as-cast state up to 45 A/m) attributed to precipitation of magnetically harder compounds (Fe3B and FeC). [ABSTRACT FROM AUTHOR]

In this study it was investigated influence of temperature and frequency on permeability, coercivity and power loses of Fe81B13Si4C2 amorphous alloy. Magnetic permeability measurements performed in nonisothermal and isothermal conditions was confirmed that efficient structural relaxation was occurred at temperature of 663 K. This process was performed in two steps, the first one is kinetic and the second one is diffuse. Activation energies of these processes are: Ea1 = 52.02 kJ/mol for kinetic and Ea2 = 106.9 kJ/mol for diffuse. It was shown that after annealing at 663 K coercivity decrease about 30% and therefore substantial reduction in power loses was attained. Investigated amorphous alloy satisfied the criteria for signal processing devices that work in mean frequency domain. [ABSTRACT FROM AUTHOR]

Development of materials with desirable properties essentially depends on realization of interdependence: natural science ⟺ technical sciences. Taking this into account, in order to develop of new advanced materials it is essential to determine principles that characterize this interdependency. Therefore, in this article the principles of fundamental research and the importance of obtained results are considered and implemented in the field of technical realizations. [ABSTRACT FROM AUTHOR]

Abstract: Glassy rods of the Fe65.5Cr4Mo4Ga4P12C5B5.5 alloy were prepared by copper-mold casting technique under argon atmosphere with diameters of 1.5 and 1.8mm. As-quenched and dc current annealed (CA) samples were examined by thermal analysis (DSC), X-ray diffraction (XRD), thermomagnetic and magnetic measurements. The appearance of a wide supercooled liquid region ΔT x ≅60K and high reduced glass transition temperature T rg ≅0.57 indicated enhanced thermal stability against crystallization. Electrical resistivity (ρ ≅210–220μΩcm), coercive field (H C ≅3–10A/m), saturation polarization (J S ≅83emu/g) and Curie temperature (T C ≅448–460K) were determined in the as-cast “XRD-amorphous” state. Maximum improvement in coercivity of about 30% was observed after applying a heating power per square area of P S ≅4.4 and 3.7W/cm2 for 1.5 and 1.8mm rods diameters, respectively. Coercivity behavior after CA treatments indicates the presence of a very small volume fraction of nanoscale crystalline inclusions that apparently hinder stress relief. [Copyright &y& Elsevier]

This paper focuses on the application of adjustable speed induction motor drives for gantry cranes. Modern solution considers application of frequency converters for all drives. Multi-motor drives are standard solutions in crane application and requirements of load sharing are present. Presented algorithm provides load sharing proportional to the rated motor power on the simple and practically applicable method on the basis of estimated torques by frequency converters, and controller realized in PLC. Special attention is devoted to wide span gantry drive and algorithm for skew elimination. Solutions for load distribution in multi-motor drive, as well as mode of gantry drive skew elimination, are described. Suggested solution concept is confirmed by the experimental results.

Powder mixture of 50 mass % of barium titanate (BaTiO3) and 50 mass % of iron (Fe) was prepared by solid-state reaction technique, i.e. ball milled in air for 60 min, 80 min, 100 min, 120 min and 150 min. During mechanochemical activation it was observed the iron powder transitsion to iron oxides. Depending on the activation time the content of iron oxides FeO, Fe2O3 and Fe3O4 varies. Simultaneously, with the content change of the activated system, magnetic properties change as well. The XRD analysis of milled samples shown that as the activation time increase, the iron oxide percentage increases to, whereby the percentage of BaTiO3 in a total sample mass decreases. The percentage of iron oxides and BaTiO3 in annealed samples changes depending on annealing temperature. The thermomagnetic measurements performed by Faraday method shown that the powder mixture milled for 100 minutes exhibit maximum magnetization prior to annealing. The increase of magnetization maximum was observed after annealing at 540°C with all milled samples, and at room temperature it has enhancement from 10 % to 22 % depending on the activation time. The samples milled for 100 min and 150 min and then sintered at 1200w°C exhibit magnetoelectric properties. [Projekat Ministarstva nauke Republike Srbije, br. 172057]

This paper investigates the thermal and magnetic properties of two iron based amorphous alloys with different Fe-content: Fe89.8Ni1.5Si5.2B3C0.5 and Fe81B13Si14C2. The XRD results show that the thermal induced structural changes occur in the temperature range of 3000C - 8500C for the Fe89.8Ni1.5Si5.2B3C0.5 amorphous alloy. The appearance of the first crystallization peaks on DSC thermograms of Fe81B13Si4C2, amorphous alloy is perceived already at 4500C. The initial magnetization curves of the as-cast sample of the Fe89.8Ni1.5Si5.2B3C0.5 amorphous alloy, obtained at the frequencies of 50 Hz, 400 Hz and 1000 Hz show the excellent match. The maximum relative magnetic permeability for Fe89.8Ni1.5Si5.2B3C0.5 alloy sample is achieved at magnetic field strength of about 20 A/m for all frequencies, whereas the values of about 7000 were obtained at the frequencies of 50 Hz and 400 Hz. The influence of frequency on total power losses, for both alloys exhibits the increase of core losses with frequency increase. The amorphous alloy Fe89.8Ni1.5Si5.2B3C0.5 toroidal core exhibits about 3 time higher total power losses. [Projekat Ministarstva nauke Republike Srbije, br. 172057]

In this study, the evolution of the nanostructure on dc Joule heated Fe72Al5Ga2P11C6B4 metallic glass ribbons have been investigated. Heating power per square area (PS) was ranging between 0.8 to 7.1 W/cm2 in order to get various stages of relaxation or nanocrystallization. The crystallization starts after applying PS ≈ 4.35 W/cm2 and the sample consist of residual amorphous matrix, a magnetic crystalline component and also a non-magnetic crystalline component (relative abundance of Fe in the crystalline phase is about 35 %). XRD measurements show that crystalline samples after current annealing consist of Fe3B, FeC, FeP and Fe3P compounds. On TEM micrograph a broad distribution of shapes and sizes is noticed, the latter range from about 60 to 350 nm, increasing by applied heating power. The decrease of the electrical resistivity after each current annealing treatment is rather small in comparison with other Fe-based amorphous alloys (only about 1.5 % for the highest PS). Partial nanocrystallization leads to increase of coercive field (from HC ≈ 7 A/m in the amorphous as-cast state up to 45 A/m) attributed to precipitation of magnetically harder compounds (Fe3B and FeC).

The present study attempted to investigate how chronic cerebral hypoperfusion (CCH) and repeated low-dose progesterone (P) treatment affect gene and protein expression, subcellular distribution of key apoptotic elements within protein kinase B (Akt) and extracellular signal-regulated kinases (Erk) signal transduction pathways, as well as neurodegenerative processes and behavior. The results revealed the absence of Erk activation in CCH in cytosolic and synaptosomal fractions, indicating a lower threshold of Akt activation in brain ischemia, while P increased their levels above control values. CCH induced an increase in caspase 3 (Casp 3) and poly (ADP-ribose) polymerase (PARP) gene and protein expression. However, P restored expression of examined molecules in all observed fractions, except for the levels of Casp 3 in synapses which highlighted its possible non-apoptotic or even protective function. Our study showed the absence of nuclear factor kappa-light-chain-enhancer of activated b cells (NF-κB) response to this type of ischemic condition and its strong activation under the influence of P. Further, the initial increase in the number of apoptotic cells and amount of DNA fragmentation induced by CCH was significantly reduced by P. Finally, P reversed the CCH-induced reduction in locomotor activity, while promoting a substantial decrease in anxiety-related behavior. Our findings support the concept that repeated low-dose post-ischemic P treatment reduces CCH-induced neurodegeneration in the hippocampus. Neuroprotection is initiated through the activation of investigated kinases and regulation of their downstream molecules in subcellular specific manner, indicating that this treatment may be a promising therapy for alleviation of CCH-induced pathologies. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the influence of the abutment angulation upon the strain distribution pattern for the vertical loading situation by means of the digital image correlation (DIC) method. In addition, to find the correlation between acrylic‐layer thickness around implant body and surfaces strain induced by vertical loads. Two types of samples consisted of the Straumann® cylindrical dental implant system (4 × 10 mm) with the SLActive® surface and the poly‐methyl‐methacrylate were used in this study. For strain analysis, the DIC system was used, manufacturer GOM. The optical deformation measurement system consists of special set of stereo cameras and lenses, and ARAMIS software (6.2.0, Braunschweig, Germany). Maximum von Mises strain was 0.30% in the sample with the straight abutment and 0.50% in the sample with the angled abutment. Minimum strain measured by Aramis was 0.01%, detected in the 6 mm surface layer of the sample with straight abutment. According to results obtained by Aramis data processing, the 4 mm surface layer indicated greater overall strain in apical direction with the strains of 0.18–0.50%, depending on the force intensity. Higher strain was noticed in the thinner surface layers. The angulated abutment induced higher strain in both surface layers than the straight abutment did. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to examine the rapid non-genomic effect of 17β-estradiol (E2) on Ca2+ transport in mitochondria isolated from the nerve terminals (synaptosomes) of caudate nuclei (NC) and brain stems (BS) of ovariectomised female rats. In physiological conditions no effect of E2 on Ca2+ influx into synaptosomal mitochondria through ruthenium red (RR)-sensitive uniporter was observed. However, in the presence of uncoupling agent carbonyl cyanide4-(trifluoromethoxy)phenylhydrazone (FCCP) (1μmol/l), pre-treatment with 0.5nmol/l E2 protected mitochondrial membrane potential and consequently increased Ca2+ influx (2.3-fold in NC and 3.1-fold in BS). At the same time, 0.5nmol/l E2 by increasing the affinity of mitochondrial Na+/Ca2+ exchanger for Na+ inhibited mitochondrial Ca2+ efflux in NC and BS by about 40%. Also, the specific binding of physiological E2 concentrations (0.1–10nmol/l) to isolated synaptosomal mitochondria was detected. Using membrane impermeable E2 bound to bovine serum albumin and selective inhibitor of mitochondrial Na+/Ca2+ exchanger, we obtained that E2’s action on mitochondrial Ca2+ efflux at least partially is due to the direct effects on the mitochondrial membrane and/or Na+/Ca2+ exchanger located in inner mitochondrial membrane. Our results implicate E2 as a modulator of Ca2+ concentration in mitochondrial matrix, and ultimately in the cytosol. Given the vital role of Ca2+ in regulation of total nerve cells activity, especially energy metabolism, neurotransmission and directing the cells toward survival or cell death, the effects on mitochondrial Ca2+ transport could be one of the important modes of E2 neuromodulatory action independent of the genome. [Copyright &y& Elsevier]

Abstract: The differential scanning calorimetry method was used for investigating the crystallization process of the Fe89.8Ni1.5Si5.2B3C0.5 amorphous alloy. It was shown that the examined alloy crystallizes in three stages. The first crystallization stage occurs at 799K, the second at 820K and the third at 888K. Temperature dependence of the magnetic susceptibility relative change was investigated by the modified Faraday method in the temperature region from room temperature up to 900K. It has been established that the Curie temperature is about 700K for amorphous state. The magnetic susceptibility increases by 30% after the first heating up to 710K. During the second heating up to 840K the alloy loses its ferromagnetic features in the temperature region from 710 to 750K, upon which it again regains the same. After the second heating magnetic susceptibility decreases by 23% as compared to the amorphous starting value and by 53% as compared to the value before the second heating. The crystallized alloy maintains ferromagnetic features in the whole temperature region during the heating up to 900K. [Copyright &y& Elsevier]

Exposure to the neurotoxin trimethyltin (TMT) selectively induces hippocampal neuronal injury and astrocyte activation accompanied with resultant neuroinflammation, which causes severe behavioral, cognitive, and memory impairment. A large body of evidence suggests that flaxseed oil (FSO), as one of the richest sources of essential omega-3 fatty acids, i.e., α-linolenic acids (ALA), displays neuroprotective properties. Here, we report the preventive effects of dietary FSO treatment in a rat model of TMT intoxication. The administration of FSO (1 mL/kg, orally) before and over the course of TMT intoxication (a single dose, 8 mg/kg, i.p.) reduced hippocampal cell death, prevented the activation of astrocytes, and inhibited their polarization toward a pro-inflammatory/neurotoxic phenotype. The underlying protective mechanism was delineated through the selective upregulation of BDNF and PI3K/Akt and the suppression of ERK activation in the hippocampus. Pretreatment with FSO reduced cell death and efficiently suppressed the expression of inflammatory molecules. These beneficial effects were accompanied by an increased intrahippocampal content of n-3 fatty acids. In vitro, ALA pretreatment prevented the TMT-induced polarization of cultured astrocytes towards the pro-inflammatory spectrum. Together, these findings support the beneficial neuroprotective properties of FSO/ALA against TMT-induced neurodegeneration and accompanied inflammation and hint at a promising preventive use of FSO in hippocampal degeneration and dysfunction.

This study aimed to comprehensively understand the performance and degradation of both p- and n-channel vertical double diffused MOS (VDMOS) transistors under bias temperature stress. Conducted experimental investigations involved various stress conditions and annealing processes to analyze the impacts of BT stress on the formation of oxide trapped charge and interface traps, leading to threshold voltage shifts. Findings revealed meaningful threshold voltage shifts in both PMOS and NMOS devices due to stresses, and the subsequent annealing process was analyzed in detail. The study also examined the influence of stress history on self-heating behavior under real operating conditions. Additionally, the study elucidated the complex correlation between stress-induced degradation and device reliability. The insights contribute to optimizing the performance and permanence of VDMOS transistors in practical applications, advancing semiconductor technology. This study underscored the importance of considering stress-induced effects on device reliability and performance in the design and application of VDMOS transistors.

The three-point bending test is a valuable method for evaluating the mechanical properties of 3D-printed biomaterials, which can be used in various applications. The use of 3D printing in specimen preparation enables precise control over material composition and microstructure, facilitating the investigation of different printing parameters and advanced materials. The traditional approach to analyzing the mechanical properties of a material using a three-point bending test has the disadvantage that it provides only global information about the material's behavior. This means that it does not provide detailed insight into the local strain distribution within the material. However, the 2D Digital Image Correlation (DIC) method offers additional insight, especially in terms of strain localization. DIC is an optical technique that measures full-field displacements and strains on the surface of a sample. PLA and enhanced PLA-X material were utilized to create three-point bending samples. The aim of this paper was to analyze and compare the influence of aging on the mechanical properties of PLA and enhanced PLA-X materials using three-point bending coupled with the DIC method. The results showed statistically significant differences between the PLA and PLA-X, for both the new and aged materials. The aged PLA samples had the highest average value of maximal force around 68 N, which was an increase of 8.8% compared to the new PLA samples. On the other hand, the aged PLA-X material had an increase of 7.7% in the average maximal force compared to the new PLA-X samples. When comparing the two materials, the PLA samples had higher maximal force values, 6.2% for the new samples, and 7.3% for the aged samples. The DIC results showed that both the new PLA and PLA-X samples endured higher strain values at Points 1 and 2 than the aged ones, except for the aged PLA-X sample at Point 2, where the new sample had higher strain values. However, for the first 5 min of the experiment, both materials exhibited identical behavior, after which point significant differences started to occur for both materials, as well as at Points 1 and 2. A more profound comprehension of the biomechanical characteristics of both PLA and PLA-X material is essential to enhance the knowledge for potential biomedical applications. The DIC method was found to be a powerful tool for analyzing the deformation and failure behavior of samples and for complementing the traditional approach to material testing.

Introduction: We aimed to describe neurological manifestations and functional outcome at discharge in patients with West Nile neuroinvasive disease., Methods: This retrospective study enrolled inpatients treated in the University Clinic for Infectious and Tropical Diseases in Belgrade, Serbia, from 1 June until 31 October 2022. Functional outcome at discharge was assessed using modified Rankin scale., Results: Among the 135 analyzed patients, encephalitis, meningitis and acute flaccid paralysis (AFP) were present in 114 (84.6%), 20 (14.8%), and 21 (15.6%), respectively. Quadriparesis/quadriplegia and monoparesis were the most frequent forms of AFP, present in 9 (6.7%) and 6 (4.4%) patients, respectively. Fourty-five (33.3%) patients had cerebellitis, 80 (59.3%) had rhombencephalitis, and 5 (3.7%) exhibited Parkinsonism. Ataxia and wide-based gait were present in 79 (58.5%) patients each. Fifty-one (37.8%) patients had tremor (41 (30.3%) had postural and/or kinetic tremor, 10 (7.4%) had resting tremor). Glasgow coma score (GCS) ≤ 8 and respiratory failure requiring mechanical ventilation developed in 39 (28.9%), and 33 (24.4%) patients, respectively. Quadriparesis was a risk factor for prolonged ventilator support (29.5 ± 16.8 vs. 12.4 ± 8.7 days, p = 0.001). At discharge, one patient with monoparesis recovered full muscle strength, whereas 8 patients with AFP were functionally dependent. Twenty-nine (21.5%) patients died. All of the succumbed had encephalitis, and 7 had quadriparesis. Ataxia, tremor and cognitive deficit persisted in 18 (16.9%), 15 (14.2%), and 22 (16.3%) patients at discharge, respectively. Age, malignancy, coronary disease, quadriparesis, mechanical ventilation, GCS ≤ 8 and healthcare-associated infections were risk factors for death (p = 0.001; p = 0.019; p = 0.004; p = 0.001; p < 0.001; p < 0.001, and p < 0.001, respectively)., (© 2023. Fondazione Società Italiana di Neurologia.)

Additive manufacturing technologies have developed rapidly in recent decades, pushing the limits of known manufacturing processes. The need to study the properties of the different materials used for these processes comprehensively and in detail has become a primary goal in order to get the best out of the manufacturing itself. The widely used thermoplastic polymer material acrylonitrile butadiene styrene (ABS) was selected in the form of both filaments and ABS-like resins to investigate and compare the mechanical properties through a series of different tests. ABS-like resin material is commercially available, but it is not a sufficiently mechanically studied form of the material, which leads to the rather limited literature. Considering that ABS resin is a declared material that behaves like the ABS filament but in a different form, the objective of this study was to compare these two commercially available materials printed with three different 3D printers, namely Fused Deposition Modelling (FDM), Stereolithography (SLA) and Digital Light Processing (DLP). A total of 45 test specimens with geometries and test protocols conforming to the relevant standards were subjected to a series of tensile, three-point bending and compression tests to determine their mechanical properties. Characterization also included evaluation of morphology with 2D and 3D microscopy, dimensional accuracy of 3D scans, and Shore A hardness of each material and 3D printing process. Tensile testing results have shown that FDM toughness is 40% of the value for DLP. FDM elongation at break is 37% of DLP, while ultimate tensile stress for SLA is 27% higher than FDM value. Elastic modulus for FDM and SLA coincide. Flexure testing results indicate that value of DLP flexural modulus is 54% of the FDM value. SLA strain value is 59% of FDM, and DLP ultimate flexure stress is 77% of the value for FDM. Compression test results imply that FDM specimens absorb at least twice as much energy as vat polymerized specimens. Strain at break for SLA is 72% and strain at ultimate stress is 60% of FDM values. FDM yield stress is 32% higher than DLP value. SLA ultimate compressive stress is half of FDM, while value for DLP compressive modulus is 69% of the FDM value. The results obtained are beneficial and give a more comprehensive picture of the behavior of the ABS polymers used in different forms and different AM processes.

Adenosine 5'-triphosphate (ATP) and other nucleotides and nucleosides, such as adenosine, are versatile signaling molecules involved in many physiological processes and pathological conditions in the nervous system, especially those with an inflammatory component. They can be released from nerve cells, glial cells, and vascular cells into the extracellular space where they exert their function via ionotropic (P2X) or metabotropic (P2Y) receptors. Signaling via extracellular nucleotides and adenosine is regulated by cell-surface located enzymes ectonucleotidases that hydrolyze the nucleotide to the respective nucleoside. This review summarizes a histochemical approach for detection of ectonucleotidase activities in the cryo-sections of brain tissue. The enzyme histochemistry (EHC) might be used as suitable replacement for immunohistochemistry, since it gives information about both localization and activity, thus adding a functional component to a classical histological approach. With this technique, it is possible to visualize spatial distribution and cell-specific localization of ecto-nucleoside triphosphate diphosphohydrolases (NTPDases) and ecto-5'-nucleotidase (eN/CD73) activities during brain development, after different hormonal manipulations, during neurodegeneration, etc. EHC is also suitable for investigation of microglial morphology in different (patho)physiological conditions. Furthermore, the review describes how to quantify EHC results., (©The Author(s) 2022. Open Access. This article is licensed under a Creative Commons CC-BY International License.)

Anastomotic leak (AL) after colorectal cancer surgery is one of the most serious postoperative complications which has major impact on outcomes. The aim of this study was to investigate preoperative and intraoperative risk factors for AL, as well as to examine whether there are differences in risk factors for AL depending on the primary tumor location. We retrospectively reviewed records of patients having undergone colorectal surgical procedures for malignancies between January 2013 and December 2017 in a single institution. Only procedures with primary anastomosis were included. Of the 153 patients, AL occurred in 10.6% of patients with primary tumor in the sigmoid colon and rectum, and in 8.2% of patients with primary tumor in the proximal sections of the colon. On univariate analysis, delayed oral intake and more advanced histologic stages of the tumor were significantly correlated with AL in patients with tumors in the sigmoid colon and rectum, and multiorgan resection and distant metastases in patients with tumors in the proximal sections of the colon. In conclusion, risk factors for the occurrence of AL vary depending on the primary tumor location and further investigation is needed to provide better insight into these differences.