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The article focuses on the "Modern Techniques in Observational Astronomy" conference, from July 1 to 5, 2024, at the Sustainable Development Center, in Romania. It states that the conference aimed to synthesize astronomical observational assets in Romania and officially open the Berthelot astronomical observational facility. It mentions that the event included discussions on various astronomical topics such as space weather, space debris, and satellite risks.

This manuscript highlights the behavior of a biodegradable polymer (Arboblend V2 Nature) coated with three distinct ceramic powders, Cr2O3–chromium oxide thermal spray powder, ZrO2 18TiO2 10Y2O3–zirconia–titania–yttria composite powder and Cr2O3-xSiO2-yTiO2–chromia–silica composite powder. The coated was realized on injected samples by using the Atmospheric Plasma Spray (APS) technique. The current investigation will explain the results related to the surface quality, micro-structure, morphology, mechanical, thermal and tribological properties. Thus, from a structural point of view the most uniform deposition was obtained in the case of composite powder based on zirconia. The thermal behavior of the samples coated with ceramic micro layers achieved stability up to temperatures slightly above 200 °C, pyrolysis taking place around 340 °C. The micro indentation, DMA, and scratch analysis responses were significantly influenced by the crystalline structure of the samples and the presence of the Cr2O3 compound. Based on the increased characteristics of the coated samples the authors of the present paper consider that from parts made of biodegradable polymers and coated with ceramic micro-particles are appropriate for some applications that required harsh operating conditions.

Context. Meteoroid streams are fragments of matter produced by comets or asteroids which intersects the orbit of Earth. Meteor showers are produced when Earth intersects these streams of matter. The discoveries of active asteroids and extinct comets open a new view of the relation between these objects as possible parent bodies at the origin of meteor showers. Aims. The aim of this work is to identify the asteroids that can produce or re-populate meteoroid streams by determining the similarity of their orbits and orbital evolution over 10 000 yr. Methods. The identification was carried out by evaluating several well known D-criteria metrics, the orbits being taken from the IAU Meteor Data Center database and from IAU Minor Planet Center. Finally, we analyzed the physical properties and the orbital stability (in the Lyapunov time sense) of the candidates as well as their possible relationship with meteorites. Results. 206 near-Earth asteroids (NEAs) were associated as possible parent bodies with 28 meteor showers, according to at least two of the criterion used. 50 of them satisfied all the criteria. Notable finds are: binary asteroid 2000UG11 associated with Andromedids (AND), while the tumbling asteroid (4179)Toutatis could be associated with October Capricornids (OCC). Other possible good candidates are 2004TG10, 2008EY5, 2010CF55, 2010TU149 and 2014OY1. These objects have low albedo, therefore can be primitive objects. Asteroid 2007LW19 which is a fast rotator and most probably has monolithic structure and so its physical characteristic does not support the association found based on the dynamical criteria [ABSTRACT FROM AUTHOR]

A research is reported on the nanomechanics and tribology of the Arboblend V2 Nature biopolymer (a 100% bio-based material, biodegradable, or resistant depending of application), being a mixture of different biopolymers such as lignin, polylactic acid, cellulose, biopolyamides, and other natural additives. The specimens were made by an industrial-scale injection molding machine. The nanoindentation characterization have unveiled that an increase in processing temperature from 160°C to 170°C produces a rise in hardness and elastic modulus of ∼20%. Tribological characterization against a bearing-steel counterface has shown that for both processing temperatures, the increase of the applied load or the increase of sliding speed will produce an increase of the friction coefficient (µ) and wear. At an applied load of 1 N (contact pressure of 104 MPa) and tracks in a direction perpendicular to the surface textured lines, the lowest µ ∼ 0.148 are for samples made T = 170°C, while for tracks parallel to the textured lines, the lowest µ ∼ 0.059 is obtained for samples made at T = 160°C. Experiments made at different ambient humidity have established that friction coefficient is higher at 0% RH or at 75% RH than at 33% RH. Our results show that the biopolymers Arboblend V2 Nature is a candidate to substitute some popular fossil-based thermoplastics in numerous tribological industrial applications.

Context. The Sloan Digital Sky Survey (SDSS) and Wide-field Infrared Survey Explorer (WISE) provide information about the surface composition of about 100 000 minor planets. The resulting visible colors and albedos enabled us to group them in several major classes, which are a simplified view of the diversity shown by the few existing spectra. A large set of data in the 0.8−2.5 μm, where wide spectral features are expected, is required to refine and complement the global picture of these small bodies of the solar system. Aims. We aim to obtain the near-infrared colors for a large sample of solar system objects using the observations made during the VISTA-VHS survey. Methods. We performed a serendipitous search in VISTA-VHS observations using a pipeline developed to retrieve and process the data that corresponds to solar system objects (SSo). The resulting photometric data is analyzed using color−color plots and by comparison with the known spectral properties of asteroids. Results. The colors and the magnitudes of the minor planets observed by the VISTA survey are compiled into three catalogs that are available online: the detections catalog (MOVIS-D), the magnitudes catalog (MOVIS-M), and the colors catalog (MOVIS-C). They were built using the third data release of the survey (VISTA VHS-DR3). A total of 39 947 objects were detected, including 52 NEAs, 325 Mars Crossers, 515 Hungaria asteroids, 38 428 main-belt asteroids, 146 Cybele asteroids, 147 Hilda asteroids, 270 Trojans, 13 comets, 12 Kuiper Belt objects and Neptune with its four satellites. The colors found for asteroids with known spectral properties reveal well-defined patterns corresponding to different mineralogies. The distributions of MOVIS-C data in color−color plots shows clusters identified with different taxonomic types. All the diagrams that use (Y − J) color separate the spectral classes more effectively than the (J − H) and (H − Ks) plots used until now: even for large color errors (<0.1), the plots (Y − J) vs. (Y − Ks) and (Y − J) vs. (J − Ks) provide the separation between S-complex and C-complex. The end members A, D, R, and V-types occupy well-defined regions. [ABSTRACT FROM AUTHOR]

During the testing of the materials' cavitation erosion resistance on vibratory systems by direct method (ASTM G32), the thread from the ultrasonic horn - test specimen connection, is subjected to fatigue. Operational experience has shown the occurrence of cracks and fractures in this area after a number of stress cycles that was lower than anticipated. The paper presents an analysis applied on four types of ultrasonic horns geometries: the original geometry with an external thread M12 and three modified geometries, with an internal thread M10 and M8. The four geometries were subjected to static analysis in order to determine the stress distribution. Based on static analysis, the behavior of the horns to fatigue was simulated and analyzed, determining the fatigue life, safety factors and optimal geometry. [ABSTRACT FROM AUTHOR]

Introduction: Cosmic objects are impacting the Earth's atmosphere on a daily basis. Due to their small size, these meteoroids cannot be seen before interacting with the air particles. Thus, to better constrain the size of an impactor, we need calibrated multi-detector observations of meteoroid impacts into our atmosphere. These recording instruments range from cameras and radio antennas [1], to detections of meteoroid airwaves using infrasound arrays, and seismic detectors, which measure the signal produced by airwave-to-ground coupling of large events. Purpose: In this study we explore several techniques of measuring the pre-atmospheric mass of meteoroids with well-known trajectory (also a subject of meteorite recoveries), at the source of ton TNT-scale atmospheric impacts [2]. On this scale, the impact is less likely to cause an airwave signal detectable on multiple specialized stations, or the estimation methods carry high uncertainty [e.g. 3, 4], hence, their mass is poorly constrained. The bolides: To compare the reliability of the energy estimation methods, first, the meteoroid-derived measurements were collected from the literature. The resulted list pointed to the object's radiation as the most common measured property of the event. Thus, the analysis focused on the optical energy signature of the objects. Most of the bolides did not have their total radiated energy estimated, hence, this was obtained based on the published light curve. Next, their kinetic energy was computed based on given estimates of velocity and mass. Results & Discussion: To derive the empirical relation, a best fit was obtained from the source energy vs the optical energy (Fig. 1). Although the radiated light and mass would ideally be modelled as a function of velocity, the obtained relation [2] shows a good correlation between the object's kinetic energy at entry and its capability of radiating light during deceleration, regardless of the object's fragmentation and ablation profile. Conclusion & Implications: The result represents a (more accurate) continuation of the relation presented by [5], towards more frequent, lower scale impactors. The applicability of this relation is not limited to cameras. A better estimate of the radiated light can be obtained with calibrated radiometers e.g., [6] or from the next generation lightning mappers [7]. Their relative luminosity is not affected by clouds, and can be coupled with the trajectory triangulation obtained by the currently expanding ground-based fireball networks e.g., [1], [8], [9], etc. to compute the object's mass. This, in turn will help to cross-calibrate the methods, which can be further used to constrain the size-frequency distribution of impacts, thus, estimating the mass of objects endangering the rapidly increasing civilian infrastructure surrounding the Earth. [ABSTRACT FROM AUTHOR]

Context. The Taurid Complex is a massive stream of material in the inner part of the Solar System. It contains objects spanning the range of 10-6-103 m, considered by some authors to have a common cometary origin. The asteroids belonging to Taurid Complex are on Apollo type orbit, with most of them being flagged as potentially hazardous asteroids. In this context, understanding the nature and the origin of this asteroidal population is not only of scientific interest but also of practical importance. Aims. We aim to investigate the surface mineralogy of the asteroids associated with Taurid Complex using visible and near-infrared spectral data. Compositional linking between these asteroids and meteorites can be derived based on the obtained spectra. Methods. We obtained spectra of six of the largest asteroids (2201, 4183, 4486, 5143, 6063, and 269690) associated with Taurid complex. The observations were made with the IRTF telescope equipped with the spectro-imager SpeX. Their taxonomic classification is made using Bus-DeMeo taxonomy. The asteroid spectra are compared with the meteorite spectra from the Relab database. Mineralogical models were applied to determine their surface composition. All the spectral analysis is made in the context of the already published physical data. Results. Five of the objects studied in this paper present spectral characteristics similar to the S taxonomic complex. The spectra of ordinary chondrites (spanning H, L, and LL subtypes) are the best matches for these asteroid spectra. The asteroid (269690) 1996 RG3 presents a flat featureless spectrum which could be associated to a primitive C-type object. The increased reflectance above 2.1 microns constrains its geometrical albedo to a value around 0.03. Conclusions. While there is an important dynamical grouping among the Taurid Complex asteroids, the spectral data of the largest objects do not support a common cometary origin. Furthermore, there are significant variations between the spectra acquired until now. [ABSTRACT FROM AUTHOR]

Thispaper presentssimulations that highlight the influence of the friction pendulum radius on the behavior of isolated structures. A model was created in SolidWorks, whichis employed to find out the structural response. The excitationin term ofdisplacements, ensured by a feature of the software program,follows asine function. The study has shown the frequencyevolution with the radius increase, along with the displacement of the isolated structure.

Coating of bio-based polymers with ceramic layer has attracted interest recently, the research topic raising difficulties regarding the technology of obtaining layers that involve very high working temperatures. The study aims to analyses the mechanical, tribological and structural characteristics of the Arboblend V2 Nature biodegradable polymer after the deposition of ceramic microlayers. The micro powders used were Amdry 6420 (Cr2O3), Metco 143 (ZrO2 18TiO2 10Y2O3) and Metco 136F (Cr2O3-xSiO2-yTiO2). The coated samples were obtained by injection molding and the deposition was achieved by using Atmospheric Plasma Spray (APS) method. The results of the related analyses showed that, in general, the deposits of ceramic micro particles increased the material surface characteristics (hardness, scratch resistance, apparent friction coefficient), due to the uniformity of the ceramic coating on the polymeric substrate. Based on these, it was possible to recommend the use of coated bio-based polymer - Arboblend V2 Nature in harsh operating conditions, such as the automotive industry.

The processing of composite materials with metal matrix reinforced with carbon particles, graphite or SiC (Silicon Carbide) is decisively determined by the transfer of the reinforcing particles from the gaseous atmosphere into the molten metal and then by their transfer from liquid into solid. The degree of incorporation, the uniformity of particle distribution and finally all the properties of the composite materials depend on the way in which the transfer conditions from one phase to another have been accomplished. According to the thermodynamic principles, the transfer of the reinforcing particles from one phase to another can happen without external energy input only if the variation of the total free enthalpy is negative. The estimation of the direction of transfer can be done after the determination of critical measurements to the balance of forces that act on the reinforcing element. The particles wetted by the liquid metal and with density of its nearest will be integrated in the melt without external energy input, and those dry and light need additional energy consumption (powder injection, melt stirring etc.). The stalling speed of the SiC particles to the gas/liquid interface is influenced by the density difference and the reinforcing particles size. The critical moving speed of the solidification front is decisively influenced by the difference between σPS and σPS, inter-phase tensions, as well as by the reinforcing particles size, if their density significantly differs from the one of the liquid alloy. Compared with the initially used alloy, the pull strength is doubled for some samples of obtained composite material. The ultrasonic testing disclosed the presence of some very small spots (porosities) which don't have a major influence on the tensile specimens subjected to pulling. From this reason, a very clear display of the bottom echo can be observed, which justifies the uniformity of the casting process. At the level of the matrix, the presence of the carbon to the separation limit between matrix and reinforcement can be observed, which confirms that during the processing Aluminium Carbide Al4C3 has been formed. The presence of these carbides considerably improves the wetting process. [ABSTRACT FROM AUTHOR]

BSTRACT [ABSTRACT FROM AUTHOR]

The social status of the school, the qualitative expectations of the beneficiaries of education, the contradictory changes in the pre-university education system and the social dimension of the school organization are factors that underline the imperative of the educational leadership, presented in the literature as an innovative leadership paradigm. Based on competencies (selfknowledge, self-mastery, social consciousness and relationship management), leadership from change perspective is present in the following areas: education, health, politics, army, or religion.

These are the first results of an observational program devoted to the complete physical data of asteroids that could produce or feed meteoroid streams. Our results are based on the optical observation at Pic du Midi observatory in April 6–7, 2016 and January 17–18, 2018. We will present the light curve of asteroid (259221) 2003 BA21, associated with Daytime Sextantids (221 DSX) and November θ Aurigids (390 THA); the light curves and colors of asteroid (363599) 2004 FG11, associated with Daytime ζ Perseids (172 ZPE) as well as g − r and g − i; and the corresponding reflectances for the (85953) 1999 FK21, associated with Daytime ξ Sagittariids (100 XSA). We will also present the colors for two additional objects, namely, (5141) Tachibana and (43032) 1999 VR26. [ABSTRACT FROM AUTHOR]

Highly accurate astrometry of asteroids in the frame of QSOs will provide the direct link between the Dynamical Reference Frame and the International Celestial Reference Frame. We propose a procedure that implies a selection of events for asteroids with accurately determined orbits crossing the CCD field containing the selected quasars. For asteroid ephemerides, a numerical integration method coupled with precise modelling of asteroid brightness will be used for analyzing our observations. A list of predictions for this type of “close approaches” will be presented. [ABSTRACT FROM PUBLISHER]

Astronomical Institute of Romanian Academy initiated this project in 2005. The results of researches related to the construction of mechanic systems and the proposed astrometric tasks will be finished in 2008. The module PROTEL is a result of several research groups and it will perform astrometric control observations remotely. [ABSTRACT FROM PUBLISHER]

An abstract of the article 'Modeling of asteroid spectra - M4AST," by M. Popescu, M. Birlan, and D. A. Nedelcu is presented.

This work presents an experimental analysis related to 3D-printed carbon-fiber-reinforced-polymer (CFRP) machining. A polyethylene-terephthalate-glycol (PETG)-based composite, reinforced with 20% carbon fibers, was selected as the test material. The aim of the study was to evaluate the influence of cutting conditions used in light operations on the generated surface quality of the 3D-printed specimens. For this purpose, nine specimens were fabricated and machined under a wide range of cutting parameters, including cutting speed, feed, and depth of cut. The generated surface roughness was measured with a mechanical gauge and the acquired data were used to develop a shallow artificial neural network (ANN) for prediction purposes, showing that a 3-6-1 structure is the best solution. Following this, a genetic algorithm (GA) was utilized to minimize the response, revealing that the optimal combination is 205 m/min speed, 0.0578 mm/rev feed, and 0.523 mm depth of cut, contributing to the fabrication of low friction parts and shafts with a high quality surface, as well as to the reduction of resource waste. A validation study supported the accuracy of the developed model, by exhibiting errors below 10%. Finally, a set of enhanced images were taken to assess the machined surfaces. It was found that 1.50 mm depth of cut is responsible for the generation of defects across the circumference of the specimens. Especially, combined with 150 m/min cutting speed and 0.11 mm/rev feed, more flaws are produced.

Recent developments in incremental sheet forming have resulted in the creation of novel manufacturing processes that are highly adaptable and could bring significant economic benefits for advanced technologies and low-volume production. In this manuscript, the following variables were examined: the variation in the deformation forces for a part with a pyramidal trunk shape; the variation in the deformations and thinning of the Al 3003 material during the incremental forming process; and the variation in the accuracy of the incrementally formed part and the quality of the surfaces (surface roughness). The components of the forces in the incremental forming have increasing values from the beginning of the process to the maximum value due to the hardening process. The TiN-coated tool ensures lower values of the forming components. Due to the kinematics of the forming process, deviations, especially in shape, from the part in the drawing are observed, which are shown by the radius of curvature of the side wall of the part, the appearance of a radius of connection between the wall and the bottom of the part, as well as dimensional deviations that are expressed by the variation in the forming depth. Concerning the smoothness of the surfaces, it was observed that the best roughness results were obtained in the case of the TiN-coated tool.

Introduction: There are very few reported cases of robotic surgery for median arcuate ligament syndrome. This clinical condition develops when the root of the celiac trunk is compressed by the median arcuate ligament of the diaphragm. The symptoms that typically accompany this syndrome are: discomfort and pain in the upper abdominal region, particularly after eating, and weight loss. During the diagnostic process, it is important to rule out other potential causes and demonstrate compression using any imaging technique available. Transecting the median arcuate ligament is the primary focus of the surgical treatment. We report a case of robotic MAL release, focusing on the particular aspects of the surgical technique. A literature review was also performed on the topic of robotic approach for MALS. Clinical case: A 25-year-old woman presented with sudden onset severe upper abdominal pain after physical activity and eating. She was then diagnosed with median arcuate ligament syndrome by imagistic means with computer tomography, doppler ultrasound, and angiographic computed tomography. After conservative management and careful planning, we performed robotic division of median arcuate ligament. The patient was discharged from the hospital without any complaint on the second day after surgery. Subsequent imaging studies revealed no residual celiac axis stenosis. Conclusion: The robotic approach is a safe and feasible treatment modality for median arcuate ligament syndrome., (Celsius.)

Surface texturing is an engineering technology used in order to improve the surface characteristic of plastic parts obtained by injection molding. Applying this process not only changes the part surface properties, but also its topography. The novel functionalities of plastic products become useful when other materials make contact with the textured surface. Of course, these characteristics may vary depending on the laser positioning, dimensions, and geometry of the texture. The present paper presents the surface characteristics obtained after the laser texturing of the Arboblend V2 Nature biodegradable polymer. Three distinct geometries were studied: hexagonal, square, and triangular, and different behaviors of them were highlighted during surface free energy (SFE) and contact angle (WCA) measurements: a hydrophobic character for square and hexagonal geometry with distilled water as the measure liquid, and a hydrophilic character with diiodomethane as the measure liquid; for triangle geometry, the contact angle measurements were impossible to extract because the drop turns into a flat puddle. Additionally, the friction coefficient varied depending on the geometry texture, with the lowest value being recorded by the sample with hexagonal geometry. The micro-indentation tests highlighted increased surface micro-hardness compared to the basic material. The possibility of use in the practice of textured surfaces is viable; thus, based on the obtained results, there is even the possibility to replace non-biodegradable polymers from different sectors of activity.

The paper aims to investigate the behavior of Arboblend V2 Nature biopolymer samples covered with three ceramic powders, Amdry 6420 (Cr 2 O 3 ), Metco 143 (ZrO 2 18TiO 2 10Y 2 O 3 ) and Metco 136F (Cr 2 O 3 -xSiO 2 -yTiO 2 ). The coated samples were obtained by injection molding, and the micropowder deposition was achieved by using the Atmospheric Plasma Spray (APS) method, with varied thickness layers. The present study will only describe the results for nine-layer deposition because, as the number of layers' increases, the surface quality and mechanical/thermal characteristics such as wear, hardness and thermal resistance are also increased. The followed determinations were conducted: the adhesion strength, hardness on a microscopic scale by micro-indentation, thermal analysis and structural and morphological analysis. The structural analysis has highlighted a uniform deposition for the ZrO 2 18TiO 2 10Y 2 O 3 layer, but for the layers that contained Cr 2 O 3 ceramic microparticles, the deposition was not completely uniform. The thermal analysis revealed structural stability up to a temperature of 230 °C, the major degradation of the biopolymer matrix taking place at a temperature around 344 °C. The samples' crystalline structure as well as the presence of the Cr 2 O 3 compound significantly influenced the micro-indentation and scratch analysis responses. The novelty of this study is given by itself the coating of the Arboblend V2 Nature biopolymer (as base material), with ceramic microparticles as the micropowder coating material. Following the undertaken study, the increase in the mechanical, tribological and thermal characteristics of the samples recommend all three coated biopolymer samples as suitable for operating in harsh conditions, such as the automotive industry, in order to replace plastic materials.

Biodegradable materials investigation has become a necessity and a direction for many researchers worldwide. The main goal is to find sustainable alternatives which gradually replace plastics based on fossil resources from the market, because they are very harmful to the environment and to overall quality of life. In order to get to the stage of obtaining different functional parts from biodegradable materials, it is necessary to study their properties. Taking into account these shortcomings, this paper aims at the mechanical characterization (DMA-Dynamic Mechanical Analysis) and thermal degradation (thermogravimetric analysis (TGA)) of lignin-based biopolymers: Arboform LV3 Nature ® , Arboblend ® V2 Nature, and Arbofill ® Fichte Arboform ® LV3 Nature reinforced with aramid fibers. The tested samples were obtained by using the most common fabrication technique for polymers-injection molding. The obtained results for the DMA analysis showed separate polymeric-specific regions for each material and, based on the tanδ values between (0.37-0.54), a series of plastics could be proposed for replacement. The mechano-dynamic behavior could be correlated with the thermal expansion of biopolymers for temperatures higher than 50/55 °C, which are thermally stable up to temperatures of at least 250 °C.

Due to the pressing problems of today's world, regarding both the finding of new, environmentally friendly materials which have the potential to replace classic ones, and the need to limit the accelerated spread of bacteria in hospitals, offices and other types of spaces, many researchers have chosen to develop their work in this field. Thus, biopolymeric materials have evolved so much that they are gradually becoming able to remove fossil-based plastics from major industries, which are harmful to the environment and implicitly to human health. The biopolymer employed in the present study, Arboblend V2 Nature with silver nanoparticle content (AgNP) meets both aspects mentioned above. The main purpose of the paper is to replace several parts and products in operation which exhibit antibacterial action, preventing the colonization and proliferation of bacteria ( Streptococcus pyogenes and Staphylococcus aureus , by using the submerged cultivation method), but also the possibility of degradation in different environments. The biopolymer characterization followed the thermal behavior of the samples, their structure and morphology through specific analyses, such as TGA (thermogravimetric analysis), DSC (differential scanning calorimetry), SEM (scanning electron microscopy) and XRD (X-ray diffraction). The obtained results offer the possibility of use of said biocomposite material in the medical field because of its antibacterial characteristics that have proved to be positive, and, therefore, suitable for such applications. The thermal degradation and the structure of the material highlighted the possibility of employing it in good conditions at temperatures up to 200 °C. Two types of samples were used for thermal analysis: first, in the form of granules coated with silver nanoparticles, and second, test specimen cut from the sample obtained by injection molding from the coated granules with silver nanoparticles.

Aim: Contrast-enhanced ultrasound (CEUS) has become a relevant imaging method for the evaluation of focal liver le-sions (FLL). The aim of this study was to evaluate the performance of CEUS for the assessment of focal nodular hyperplasia (FNH) in a large study group., Material and Methods: We performed a multicentre prospective observational study, which included successive CEUS examinations from fourteen Romanian centres. CEUS examinations were performed in de novo FLL, using low mechanical index ultrasound, following an intravenous bolus of 2.4 ml SonoVue. CEUS was considered conclusive for FNH if a typical pattern was present following contrast (rapid "spoke-wheel" enhancement during the arterial phase, hyperenhanced lesion during venous phase, hyper- or isoenhanced in the late phase). In all cases a reference method was available (contrast enhanced CT or MRI or biopsy). The trial was registered in clinicaltrials.gov (Identifier NCT01329458)., Results: During the 6 years study, 2062 "de novo" FLL were evaluated by CEUS. From this cohort, 94/2062 (4.5%) had a typical enhancing pattern for FNH as described in the EFSUMB guidelines. Contrast enhanced CT/MRI and biopsy diagnosed additional 15 FNH. From the 94 cases diagnosed as FNH by CEUS, in nine the final diagnosis was different (five of them adenomas). CEUS had 85% sensitivity, 99.5% specificity, 90.4% positive predictive value, 99.2% negative predictive value and 98.8% diagnostic accuracy for the diagnosis of FNH., Conclusions: CEUS is a sensitive and very specific method for the diagnosis of FNH.

The ability of a receptor to preferentially activate only a subset of available downstream signal cascades is termed biased signaling. Although comprehensively recognized for the G protein-coupled receptors (GPCR), this process is scarcely explored downstream of receptor tyrosine kinases (RTK), including the cancer-relevant insulin-like growth factor-1 receptor (IGF1R). Successful IGF1R targeting requires receptor downregulation, yet therapy-mediated removal from the cell surface activates cancer-protective β-arrestin-biased signaling (β-arr-BS). As these overlapping processes are initiated by the β-arr/IGF1R interaction and controlled by GPCR-kinases (GRK), we explored GRKs as potential anticancer therapeutic targets to disconnect IGF1R downregulation and β-arr-BS. Transgenic modulation demonstrated that GRK2 inhibition or GRK6 overexpression enhanced degradation of IGF1R, but both scenarios sustained IGF1-induced β-arr-BS. Pharmacologic inhibition of GRK2 by the clinically approved antidepressant, serotonin reuptake inhibitor paroxetine (PX), recapitulated the effects of GRK2 silencing with dose- and time-dependent IGF1R downregulation without associated β-arr-BS. In vivo , PX treatment caused substantial downregulation of IGF1R, suppressing the growth of Ewing's sarcoma xenografts. Functional studies reveal that PX exploits the antagonism between β-arrestin isoforms; in low ligand conditions, PX favored β-arrestin1/Mdm2-mediated ubiquitination/degradation of IGF1R, a scenario usually exclusive to ligand abundancy, making PX more effective than antibody-mediated IGF1R downregulation. This study provides the rationale, molecular mechanism, and validation of a clinically feasible concept for "system bias" targeting of the IGF1R to uncouple downregulation from signaling. Demonstrating system bias as an effective anticancer approach, our study reveals a novel strategy for the rational design or repurposing of therapeutics to selectively cross-target the IGF1R or other RTK. SIGNIFICANCE: This work provides insight into the molecular and biological roles of biased signaling downstream RTK and provides a novel "system bias" strategy to increase the efficacy of anti-IGF1R-targeted therapy in cancer., (©2020 American Association for Cancer Research.)

It is essential to combine current state-of-the-art technologies such as additive manufacturing with current ecological needs. Due to the increasing demand for non-toxic biodegradable materials and products, human society has been searching for new materials. Consequently, it is compulsory to identify the qualities of these materials and their behavior when subjected to various external factors, to find their optimal solutions for application in various fields. This paper refers to the biodegradable Polylactic acid (PLA)-based filament (commercially known as Extrudr BDP (Biodegradable Plastic) Flax) compared with the biodegradable composite material PLA-lignin filament whose constituent's trade name is Arboblend V2 Nature as a lignin base material and reinforcement with Extrudr BDP Pearl, a PLA based polymer, 3D printed by Fused Deposition Modeling technology. Certain mechanical properties (tensile strength, bending strength and DMA-Dynamic Mechanical Analysis) were also determined. The tribology behavior (friction coefficient and wear), the structure and the chemical composition of the biodegradable materials were investigated by SEM-Scanning Electron Microscopy, EDX-Energy Dispersive X-Ray Analysis, XRD-X-Ray Diffraction Analysis, FTIR-Fourier Transform Infrared Spectrometer and TGA-Thermogravimetric Analysis. The paper also refers to the influence of technological parameters on the 3D printed filaments made of Extrudr BDP Flax and the optimization those of technological parameters. The thermal behavior during the heating of the sample was analyzed by Differential scanning calorimetry (DSC). As a result of the carried-out research, we intend to recommend these biodegradable materials as possible substituents for plastics in as many fields of activity as possible.

In order to find new ways to ensure sustainable development on a global level, it is essential to combine current top technologies, such as additive manufacturing, with the economic, ecological, and social fields. One objective of this paper refers to wire manufacture such as Arboblend V2 Nature, Arbofill Fichte, and Arboblend V2 Nature reinforced with Extrudr BDP "Pearl" (BDP-Biodegradable Plastic) in order to replace the plastic materials. After wire manufacture by extrusion, the diameter accuracy was analyzed compared with the Fiber Wood wire using SEM analyses and also EDAX-Energy Dispersive X-ray Analysis and DSC-Differential Scanning Calorimetry analyses were done in order to identify their elemental composition and the phase transitions suffered by the materials during heating. Using the samples obtained through the Fused Deposition Modeling (FDM) method, both crystalline phases and chemical composition information (XRD analysis) were identified, as well was determined the visco-elastic behavior Dynamic Mechanical Analysis (DMA), for the reinforced material and Fiber Wood. The extruded wires have allowed size for the printing equipment, around 1.75 mm with tolerance of ± 0.05 mm. The wire material diagrams, Arboblend V2 Nature reinforced with Extrudr BDP "Pearl" and Fiber Wood following the calorimetric analysis, presented peaks corresponding to material crystallization, while Arbofill Fichte revealed only the melting temperature. The storage module was almost double in case of Arboblend V2 Nature reinforced with Extrudr BDP "Pearl" compared with Fiber Wood and materials' melting temperatures were confirmed by the analyses carried out.

Aim: This study evaluated the accuracy of contrast-enhanced ultrasound (CEUS) for the differential diagnosis of benign vs. malignant focal liver lesions (FLL) in a real-life, multicenter experience., Methods: This prospective study, including 14 Romanian centers, was performed over a 6 year period (February 2011- April 2017) and included 2062 FLLs assessed by CEUS. Inclusion criteria were: newly diagnosed FLL on B-mode ultrasound, less than three lesions/patient, all FLLs evaluated by CEUS and by a second-line imaging technique (contrast enhanced CT or contrast enhanced MRI) or histology, considered as reference. The trial was registered in clinicaltrials.gov (Identifier NCT01329458)., Results: From the 2062 FLLs included in the study, 57.2% (1179) were malignant and 42.8% (883) were benign. CEUS had 83.9% sensitivity (Se), 97.8% specificity (Sp), 98.1% positive predictive value (PPV), 82.2% negative predictive value (NPV) and a diagnostic accuracy (Ac) of 89.9% for the positive diagnosis of malignant lesions. For the benign lesions, CEUS had 97.8% Se, 83.9% Sp, 82.2% PPV, 98.1% NPV 89.9% Ac. The diagnostic performance of CEUS for hepatocellular carcinoma was 76.6% Se, 98.4% Sp, and 91.2% Ac; for hemangioma: 89.2% Se, 99% Sp, and 96.9% Ac and for metastases: 90.9% Se, 98.4% Sp, and 96.9% Ac., Conclusions: CEUS proved a high accuracy in differentiating the malignant vs. benign character of a FLL. It can be confidently used as a first line imaging method in daily practice.

UNC-13 proteins play an essential role in synaptic transmission by recruiting synaptic vesicles (SVs) to become available for release, which is termed SV priming. Here we show that the C2A domain of UNC-13L, like the corresponding domain in mammalian Munc13-1, displays two conserved binding modes: forming C2A/C2A homodimers, or forming a heterodimer with the zinc finger domain of UNC-10/RIM (C2A/RIM). Functional analysis revealed that UNC-13L's C2A promotes synaptic transmission by regulating a post-priming process. Stimulus-evoked release but not SV priming, was impaired in unc-10 mutants deficient for C2A/RIM heterodimerization, leading to decreased release probability. Disrupting C2A/C2A homodimerization in UNC-13L-rescued animals had no effect on synaptic transmission, but fully restored the evoked release and the release probability of unc-10 /RIM mutants deficient for C2A/RIM heterodimerization. Thus, our results support the model that RIM binding C2A releases UNC-13L from an autoinhibitory homodimeric complex to become fusion-competent by functioning as a switch only., Competing Interests: HL, LL, DN, QH, LZ, WW, YY, JK, ZH No competing interests declared, (© 2019, Liu et al.)

The cancer-risk-associated rs6983267 single nucleotide polymorphism (SNP) and the accompanying long noncoding RNA CCAT2 in the highly amplified 8q24.21 region have been implicated in cancer predisposition, although causality has not been established. Here, using allele-specific CCAT2 transgenic mice, we demonstrate that CCAT2 overexpression leads to spontaneous myeloid malignancies. We further identified that CCAT2 is overexpressed in bone marrow and peripheral blood of myelodysplastic/myeloproliferative neoplasms (MDS/MPN) patients. CCAT2 induces global deregulation of gene expression by down-regulating EZH2 in vitro and in vivo in an allele-specific manner. We also identified a novel non-APOBEC, non-ADAR, RNA editing at the SNP locus in MDS/MPN patients and CCAT2 -transgenic mice. The RNA transcribed from the SNP locus in malignant hematopoietic cells have different allelic composition from the corresponding genomic DNA, a phenomenon rarely observed in normal cells. Our findings provide fundamental insights into the functional role of rs6983267 SNP and CCAT2 in myeloid malignancies., (© 2018 Shah et al.; Published by Cold Spring Harbor Laboratory Press.)

The synaptic adhesion molecules Neurexin and Neuroligin alter the development and function of synapses and are linked to autism in humans. In C. elegans, post-synaptic Neurexin (NRX-1) and pre-synaptic Neuroligin (NLG-1) mediate a retrograde synaptic signal that inhibits acetylcholine (ACh) release at neuromuscular junctions. Here, we show that the retrograde signal decreases ACh release by inhibiting the function of pre-synaptic UNC-2/CaV2 calcium channels. Post-synaptic NRX-1 binds to an auxiliary subunit of pre-synaptic UNC-2/CaV2 channels (UNC-36/α2δ), decreasing UNC-36 abundance at pre-synaptic elements. Retrograde inhibition is mediated by a soluble form of NRX-1's ectodomain, which is released from the post-synaptic membrane by the SUP-17/ADAM10 protease. Mammalian Neurexin-1α binds α2δ-3 and decreases CaV2.2 current in transfected cells, whereas Neurexin-1α has no effect on CaV2.2 reconstituted with α2δ-1 and α2δ-2. Collectively, these results suggest that α-Neurexin binding to α2δ is a conserved mechanism for regulating synaptic transmission., (Copyright © 2017 Elsevier Inc. All rights reserved.)

In vertebrates, sterols are necessary for Hedgehog signaling, a pathway critical in embryogenesis and cancer. Sterols activate the membrane protein Smoothened by binding its extracellular, cysteine-rich domain (CRD). Major unanswered questions concern the nature of the endogenous, activating sterol and the mechanism by which it regulates Smoothened. We report crystal structures of CRD complexed with sterols and alone, revealing that sterols induce a dramatic conformational change of the binding site, which is sufficient for Smoothened activation and is unique among CRD-containing receptors. We demonstrate that Hedgehog signaling requires sterol binding to Smoothened and define key residues for sterol recognition and activity. We also show that cholesterol itself binds and activates Smoothened. Furthermore, the effect of oxysterols is abolished in Smoothened mutants that retain activation by cholesterol and Hedgehog. We propose that the endogenous Smoothened activator is cholesterol, not oxysterols, and that vertebrate Hedgehog signaling controls Smoothened by regulating its access to cholesterol., (Copyright © 2016 Elsevier Inc. All rights reserved.)