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Purpose: The aim of our prospective randomised trial was to demonstrate the efficacy and improvement in surgical skills of inexperienced surgeons in the balloon kyphoplasty procedures trained with virtual reality (VR) compared to untrained inexperienced surgeons. Methods: Six orthopaedic residents were randomized to group VR1 (trained) and group VR0 (untrained, control group). At the beginning, all participants, after a theoretical lesson, performed a virtual kyphoplasty. Each resident of the Group VR1 did four training sessions in 1 month (2 h per week) and at the end of training was re-evaluated performing a virtual kyphoplasty. Residents were evaluated with global task completion time and rates subtask ability according to Global Rating Scale of Operative Performance adaptation (both in VR simulation and during the surgery). A percutaneous vertebral augmentation with balloon kyphoplasty was performed by all residents. Intraoperative parameters, complications and cumulative transfer effectiveness ratio (CTER) were analysed. Results: Intraoperative scores revealed an improvement in the group VR1 between the first VR trial and the intraoperative phase (2.85 ± 0.65 vs. 4.09 ± 0.62, P < 0.05), which was not seen in the group VR0 (2.71 ± 0.71 vs. 2.85 ± 0.75). Statistical analyses indicated significant differences in intraoperative scores between the two groups. The CTER was 0.85 and suggests that 10 training sessions could reduce the procedure time by approximately 8 min in a 15 min of surgery. Conclusion: Our study about the balloon kyphoplasy reaffirms the potential of VR as an effective and cost-efficient training tool, bridging the gap between theoretical knowledge and practical execution. [ABSTRACT FROM AUTHOR]

Helical plating for humeral shaft fractures has gained popularity in recent years as it avoids iatrogenic nerve damage. A total of 16 patients with humeral shaft fracture involving the metaphyseal proximal part were treated between Dicembrer 2016 and January 2023. Complications such as pseudarthrosis, infections and nerve lesions were investigated during the postoperative period. Functional outcome was quantified using the Italian version of the DASH 30 quality of life assessment item. Healing of the fracture was achieved at the last follow-up with good clinical recovery and no pain. The self-contoured Philos-Helix plate for humeral shaft fractures with proximal extension in combination with an anterior window approach is a safe procedure with good functional results at a follow-up of at least one year. Clin Ter 2024; 175 (5):318-322 doi: 10.7417/ CT.2024.5136 [ABSTRACT FROM AUTHOR]

Traumatic rupture of the long head of biceps tendon (LHBT) in the young is rare and it is often related to sports. We describe a technical note of a mini open supra-pectoral tenodesis fixed by the "ToggleLoc™" (Zimmer Biomet, Warsaw, IN, USA) and performed by a two-window approach. The proposed technique guarantees an optimal visualization with low risk of complications and without arthroscopic assistance. [ABSTRACT FROM AUTHOR]

Background. Distal metaphyseal-diaphyseal fractures of the humerus can be challenging. The success lies in achieving a stable fixation that could allow early functional recovery. Our aim is to combine different approaches already reported, to obtain an ideal surgical strategy for treating these fracture patterns. Methods. In this retrospective study, we present the clinical outcome of a 12-patient cohort in which we used a combined paratricipital and triceps-splitting approach to the distal humerus. The mean age of the group was 50 years (range 17 - 88). Clinical and radiographic evaluation was performed at 1, 3, 6, and 12 months after surgery and thereafter, depending on the necessity of a further control. Patients' range of motion (ROM) of the elbow was reported, and functional outcome was assessed using the Mayo Elbow Performance Index (MEPI).The minimum follow-up was fixed at 12 months. Results. Union was achieved in all fractures. After a median follow-up of 15.7 months (range 12-21), none of the patients complained of any limitation in daily activities. The ROM at the last follow-up was complete in eight patients. Instead, three patients had ROM limitations, but none of them mentioned Limitations in the activities of daily living. We observed a single iatrogenic radial nerve palsy undergoing a full functional recovery at the final follow-up. No further complications occurred. Conclusion. We believe that the here presented modified approach could represent a solution that meets the modern demands for both robust fixation and early mobilization, with minimal soft tissues damage around distal humeral fractures. [ABSTRACT FROM AUTHOR]

Background. Tibial plateau fractures pose multiple challenges to the surgeon given their frequent intra-articular involvement and the tendency to displace under axial load. The aim of this study is to describe the clinical outcomes of a retrospective case series in which tibial plateau fractures were not treated with PL fragment osteosynthesis. Methods. In the present retrospective study, we included patients treated for tibial plateau fracture with PL fragment in our department from January 2016 to January 2020. All patients were seen at the outpatient clinic 2 and 5 weeks after surgery, and at 3, 6 and 12 months, and thereafter at regular intervals, depending on the overall clinical status. Every patient included in this study was then contacted by phone to assess self-reported clinical outcomes. The Oxford Knee Score (OKS) questionnaire was used to assess functional outcomes. Patients were divided in six groups depending on the three-column classification by Lou (groups A1-A6). Patients were also divided in four groups based on the whole area of the PL column and on the depression of the PL fragment (group B1-B4). One-way ANOVA was used to compare groups of patients. Results. OKS scores, extension and step-off of the PL fragment were analyzed in groups A1 - A6. No significant differences between OKS scores and step-off were found, while statistical difference was found between surfaces of PL fragment. No significant difference was found between OKS scores in groups B1-B4. Conclusion. Our findings suggest that the treatment outcome is influenced not only by the superficial involvement or collapse of PL fragments, but also by other variables, including BMI, pre-injury physical health, and age. [ABSTRACT FROM AUTHOR]

Solid wine wastes named wine lees (WL) have been tested as cost‐advantage filler within biopolymers such as poly(3‐hydroxybutyrate‐co‐hydroxyhexanoate) and poly(3‐hydroxybutyrate‐co‐hydroxyvalerate). WL have been first characterized and subsequently mixed within the polymers through a twin‐screw extruder in different concentrations (10, 20, and 40 phr). Moreover, the role of 3‐methacryloxypropyltrimethoxysilane tested as coupling agent has been investigated within the 20 phr formulation. The obtained materials have been characterized from a thermal, mechanical, rheological, and morphological point of view through: differential scanning calorimetry, melt flow rate, tensile and creep tests, dynamic mechanical analysis, and scanning electron microscopy. Results have shown how WL can improve the biopolymers overall properties without compromising their bio‐based origin. Several micromechanical models have been exploited to extend the mechanical behavior and correlations between biocomposites properties and WL contents have been carried out. Finally, the economic analysis has shown how these biocomposites could be suitable also for large‐scale applications. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48869. [ABSTRACT FROM AUTHOR]

Polymeric nanocomposites containing Fe3O4 nanoparticles were prepared through a chemical route under different precursor-to-solvent ratios and were submitted to structural and morphologic characterization. The embedded nanoparticles, containing pure magnetite and characterized by considerable polydispersity, are rather homogeneously dispersed in the matrix. The magnetic properties of two representative samples were analyzed in detail between T = 5 K and room temperature. Magnetic effects clearly associated with the Verwey monoclinic to cubic transition with transition temperatures distributed in the interval 95-120 K were put in evidence. On heating through this region, the coercive field and the maximum susceptibility of hysteresis loops display marked downward/upward steps, respectively, while the high-field magnetization is not affected at all; a comparable upward step is measured in the FC/ZFC curves. Reporting the maximum susceptibility as a function of the reciprocal of the coercive field in the interval from T = 95 to T = 120 K, and using the predictions for single-domain nanoparticles with randomly distributed axes of uniaxial and cubic anisotropy (the former/latter case being applicable below/above the Verwey transition, respectively), the evolution of the transformed cubic-anisotropy fraction upon heating has been studied, and the distribution of Verwey transition temperatures related to the sample polydispersity has been accurately determined. The low-temperature value of the uniaxial anisotropy constant is obtained from coercive field measurements and found to be comparable to, albeit slightly higher than the corresponding quantity measured in bulk crystalline magnetite. [ABSTRACT FROM AUTHOR]

The preparation and thermo-mechanical characterization of composites based on polyamide 11 (PA11) filled with various amounts of both expandable and expanded graphites are presented. Investigation conducted using X-ray diffraction (XRD), scanning electron microscopy and surface area analyses indicated how graphite expanded under the selected processing conditions. The XRD analysis on PA11/graphite composites revealed no change in the crystal form of the PA11, while the presence of diffraction peaks associated to the graphite-stacked lamellae can be still detected. All the investigated composites showed an improvement of the thermal stability and mechanical properties (elastic and storage moduli). [ABSTRACT FROM AUTHOR]

Introduction In the past years, we developed a telemonitoring service for young patients affected by Type 1 Diabetes. The service provides data to the clinical staff and offers an important tool to the parents, that are able to oversee in real time their children. The aim of this work was to analyze the parents' perceived usefulness of the service. Methods The service was tested by the parents of 31 children enrolled in a seven-day clinical trial during a summer camp. To study the parents' perception we proposed and analyzed two questionnaires. A baseline questionnaire focused on the daily management and implications of their children's diabetes, while a post-study one measured the perceived benefits of telemonitoring. Questionnaires also included free text comment spaces. Results Analysis of the baseline questionnaires underlined the parents' suffering and fatigue: 51% of total responses showed a negative tendency and the mean value of the perceived quality of life was 64.13 in a 0-100 scale. In the post-study questionnaires about half of the parents believed in a possible improvement adopting telemonitoring. Moreover, the foreseen improvement in quality of life was significant, increasing from 64.13 to 78.39 ( p-value = 0.0001). The analysis of free text comments highlighted an improvement in mood, and parents' commitment was also proved by their willingness to pay for the service (median = 200 euro/year). Discussion A high number of parents appreciated the telemonitoring service and were confident that it could improve communication with physicians as well as the family's own peace of mind. [ABSTRACT FROM AUTHOR]

Aim To assess the impact on fear of hypoglycaemia and treatment satisfaction with an artificial pancreas system used for 2 consecutive months, as well as participant acceptance of the artificial pancreas system. Methods In a randomized crossover trial patient-related outcomes associated with an evening-and-night artificial pancreas and sensor-augmented pump therapy were compared. Both intervention periods lasted 8 weeks. The artificial pancreas acceptance questionnaire (range 0-90, higher scores better), Hypoglycaemia Fear Survey II (range 0-72, higher scores worse) and Diabetes Treatment Satisfaction Questionnaire (range 0-36, higher scores better) were completed by 32 participants. Semi-structured interviews were conducted after study completion in a subset of six participants. Outcomes were compared using a repeated-measures anova model or paired t-test when appropriate. Results The total artificial pancreas acceptance questionnaire score at the end of the artificial pancreas period was 69.1 ( sd 14.7; 95% CI 63.5, 74.7), indicating a positive attitude towards the artificial pancreas. No significant differences were found among the scores at baseline, end of sensor-augmented pump therapy period or end of the artificial pancreas period with regard to fear of hypoglycaemia [28.2 ( sd 17.5), 23.5 ( sd 16.6) and 23.5 ( sd 16.7), respectively; P = 0.099] or diabetes treatment satisfaction [29.0 ( sd 3.9), 28.2 ( sd 5.2) and 28.0 ( sd 7.1), respectively; P = 0.43]. Themes frequently mentioned in the interviews were 'positive effects at work', 'improved blood glucose', 'fewer worries about blood glucose', but also 'frequent alarms', 'technological issues' and 'demand for an all-in-one device'. Conclusions The psychological outcomes of artificial pancreas and sensor-augmented pump therapy were similar. Current artificial pancreas technology is promising but user concerns should be taken into account to ensure utility of these systems. [ABSTRACT FROM AUTHOR]

In this study, the effect of graphene nanoplatelets (GNPs) on the shape memory properties of poly(L-lactic acid) (PLLA) was studied. In addition to thermal activation, the possibility of infrared actuating of thermo-responsive shape memory PLLA/GNPs nanocomposite was investigated. The incorporated GNPs were expected to absorb infrared wave's energy and activate shape memory PLLA/GNPs. Different techniques such as differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXD), field emission gun scanning electron microscope (FEG-SEM) and dynamic mechanical thermal analysis (DMTA) were used to characterize samples. DSC and WAXD results indicated that GNPs augmented crystallinity due to nucleating effect of graphene particles. GNPs improved both thermal and infrared activating shape memory properties along with faster response. Pure shape memory PLLA was slightly responsive to infrared light and its infrared actuated shape recovery ratio was 86% which increased to more than 95% with loading of GNPs. Drastic improvement in the crystallinity was obtained in nanocomposites with lower GNPs contents (0.5 and 1 wt%) due to finer dispersion of graphene which resulted in more prominent mechanical and shape memory properties enhancement. Infrared activated shape memory PLLA/GNPs nanocomposites can be developed for wireless remote shape control of smart medical and bio-systems. [ABSTRACT FROM AUTHOR]

Aims To test in an outpatient setting the safety and efficacy of continuous subcutaneous insulin infusion ( CSII) driven by a modular model predictive control ( MMPC) algorithm informed by continuous glucose monitoring ( CGM) measurement. Methods 13 patients affected by type 1 diabetes participated to a non-randomized outpatient 42-h experiment that included two evening meals and overnight periods (in short, dinner & night periods). CSII was patient-driven during dinner & night period 1 and MMPC-driven during dinner&night period 2. The study was conducted in hotels, where patients could move around freely. A CGM system ( G4 Platinum; Dexcom Inc., San Diego, CA, USA) and insulin pump ( AccuChek Combo; Roche Diagnostics, Mannheim, Germany) were connected wirelessly to a smartphone-based platform (DiAs, Diabetes Assistant; University of Virginia, Charlottesville, VA, USA) during both periods. Results A significantly lower percentage of time spent with glucose levels <3.9 mmol/l was achieved in period 2 compared with period 1: 1.96 ± 4.56% vs 12.76 ± 15.84% (mean ± standard deviation, p < 0.01), together with a greater percentage of time spent in the 3.9-10 mmol/l target range: 83.56 ± 14.02% vs 62.43 ± 29.03% (p = 0.04). In addition, restricting the analysis to the overnight phases, a lower percentage of time spent with glucose levels <3.9 mmol/l (1.92 ± 4.89% vs 12.7 ± 19.75%; p = 0.03) was combined with a greater percentage of time spent in 3.9-10 mmol/l target range in period 2 compared with period 1 (92.16 ± 8.03% vs 63.97 ± 2.73%; p = 0.01). Average glucose levels were similar during both periods. Conclusions The results suggest that MMPC managed by a wearable system is safe and effective during evening meal and overnight. Its sustained use during this period is currently being tested in an ongoing randomized 2-month study. [ABSTRACT FROM AUTHOR]

Silica nanoparticles were synthesized by means of a sol-gel method and generated in ethylene propylene diene monomer rubber (EPDM) by in situ synthesis. The properties were determined using scanning electron microscopy, attenuated total reflectance Fourier-transform infrared spectroscopy, thermogravimetric analysis, tensile testing, dynamic mechanical analysis, swelling tests, and gel content determination. The silica particles were homogenously dispersed in the EPDM matrix, with the presence of agglomerates, especially for high silica contents. The swelling experiments showed a decrease in the crosslinking density of the vulcanized rubber due to the presence of the silica nanoparticles. The mechanical properties, however, were significantly improved by the presence of the stiff silica nanoparticles. The effect of the amount of silica on the thermomechanical properties and thermal degradation of EPDM was also investigated. The presence of silica showed an increase in the storage and loss moduli at high temperatures, probably due to the increasing filler content. The thermal degradation analysis showed that the presence of silica particles incorporated in the EPDM matrix had no significant influence on the thermal stability of the composites. POLYM. COMPOS., 36:825-833, 2015. © 2014 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Ethylene propylene diene monomer (EPDM) rubber composites containing in situ generated silica particles was prepared through a non-hydrolytic sol-gel (NHSG) method with silicon tetrachloride as precursor. The silica particles were homogenously dispersed in the EPDM matrix, but there were agglomerates at high silica contents. The swelling experiments showed a decrease in the crosslinking density of the vulcanized rubber due to the presence of the silica particles for both the composites prepared in the presence and absence of a coupling agent, bis-[-3-(triethoxysilyl)-propyl]-tetrasulfide (TESPT). Unlike the composites prepared through a hydrolytic sol-gel (HSG) method with TEOS as precursor, the TESPT did not seem to take part in the sol-gel reaction. The presence of TESPT influenced the interaction and dispersion of the silica particles in the EPDM matrix, which gave rise to increased thermal stability of the EPDM when compared to the composites prepared in the absence of TESPT. However, ethylene chloride and TESPT evaporated from the samples at temperatures below the EPDM decomposition range. The values of the Nielsen model parameters, that gave rise to a good agreement with the experimentally determined Young's modulus values, indicated improved dispersion and reduced size of the silica aggregates in the EPDM matrix. There was also good agreement between the storage modulus and Young's modulus values. The filler effectiveness (Factor C) indicated a mechanical stiffening effect and a thermal stability contribution by the filler, while the damping reduction (DR) values confirmed that the EPDM interacted strongly with the well dispersed silica particles and the polymer chain mobility was restricted. The tensile properties, however, were in some cases worse than those for the samples prepared through the HSG method in the presence of TEOS. [ABSTRACT FROM AUTHOR]

The present work attempts to study the mechanical properties and toughness behavior of a typical acrylic melamine clearcoat modified by a polyester-amide hyperbranched polymer (HBP). Formulations were such that 0, 5, 10, 25 and 50% (molar percent) of total acrylic hydroxyl groups were stoichiometrically substituted by those of HBP. Bulk and surface of the clearcoats were studied by various mechanical techniques including hardness, tensile, dynamic mechanical thermal analysis (DMTA), nano-indentation and scratch tests. In addition a scanning electron microscope (SEM) was utilized to observe the morphology of the fractured films. The bulk mechanical properties showed that a low loading (5 molar %) of HBP was sufficient to considerably increase the bulk hardness, cross-linking density and toughness. DMTA and SEM results proved the occurrence of a single-phase blend and that the shear deformation was the main toughening mechanism of HBP modified clearcoats. In general, it was revealed that the HBP not only could act as an excellent compatible toughening agent, but also maintained the clarity of the clearcoat and increased its scratch resistance. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The present article concerns the preparation of poly(methyl methacrylate)/titania nanocomposites by a non-conventional bottom-up approach, as alternative to the conventional mechanical compounding of preformed filler particles. Poly(methyl methacrylate) (PMMA) was modified with in situ generation of titania nanoparticles by means of the so-called non-hydrolytic sol-gel (NHSG) process in the presence of tert-butyl alcohol ( tBuOH) as oxygen donor and polymer solvent. The results showed that the synthetic procedure used permitted the preparation of the highly filled PMMA (up to 20 phr of titania in anatase form) with titania actual content values very close to the nominal ones and with enhanced filler dispersion and homogeneous distribution within the polymeric matrix, avoiding the typical rheological problems related to distributive and dispersive mixing of conventional compounding methods. The presence of titania nanoparticles led to increases in glass transition temperature and E′ modulus in the rubbery region for all the prepared samples with respect to the pristine PMMA. Finally, the nanocomposites showed an interesting photo-catalytic activity towards organic molecules. The findings led us to conclude that the NHSG process was successfully employed to produce anatase titania in the presence of tBuOH and PMMA. The proposed process seems to offer a very promising method to produce polymer nanocomposites with good filler dispersion and homogeneous distribution and with interesting functional properties such as photo-catalytic activity. [ABSTRACT FROM AUTHOR]

The sol-gel technique was used to reinforce isoprene rubber (IR) by generating silica in situ from tetraethoxysilane (TEOS). The aim of the research was to elucidate the effect of the preparation conditions on the structural and morphological characteristics of silica and the resulting mechanical reinforcement. The structure of the in situ generated silica was analyzed by 29Si high-resolution solid-state NMR spectroscopy, which evidenced a high condensation degree of TEOS that decreased with increasing the sol-gel reaction time. The silica dispersion became less homogeneous as the TEOS content and the reaction time were increased. The incorporation of a coupling agent (OTES, octyltriethoxysilane) in the reaction mixture promoted full conversion of TEOS. Lower particle size, better silica dispersion, and higher filler-matrix adhesion were noticed if the incorporation of OTES was delayed compared to TEOS. Uniaxial tensile tests evidenced that the tensile strength typically increased in the first 60 min of reaction and then leveled off. A similar behavior was observed for the high deformation stiffness, whereas at low deformations, the stiffness increased monotonically with the reaction time. In the vulcanizates with silica contents higher than 25 wt %, a drastic stiffness decrement was observed passing from low to high deformations. This reduction was ascribed to the disruption of the secondary filler network occurring in these materials when severely stretched. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

Poly(methyl methacrylate) (PMMA)/titanium dioxide (TiO) nanocomposites were prepared by means of in situ generation of TiO through a non-hydrolytic sol-gel process (NHSG), starting from titanium chloride, as titania precursor, benzyl alcohol, as oxygen donor, and commercial PMMA. TiO nanoparticles (average size of 30 nm) were obtained in the anatase and amorphous forms. The in situ generation led to a very homogeneous distribution of particulate fillers within the polymeric matrix avoiding the problems related to distributive and dispersive mixing of conventional compounding methods (top down approach). A slight increase of glass transition temperature was observed for all prepared composites with respect to the pristine PMMA. The NHSG process did not affect the molecular weight of the polymers indicating the absence of any degradation reaction for PMMA. The presence of titania in the anatase phase increases the photodegradation of the PMMA matrix due to UV irradiation. [ABSTRACT FROM AUTHOR]

Nanocomposites of polycarbonate (PC) reinforced with nanosized silica particles were prepared by a melt mixing technique in an internal mixer. Two kinds of commercial hydrophilic fumed silicas differing in their specific surface area were added in amounts up to 5% by volume, and their reinforcing action was compared to that of organically modified silica, loaded in the same amounts. Particle-matrix interactions were investigated by means of rheological and dynamic-mechanical thermal analysis, demonstrating the important role played by the organic modification in the interactions with the polymer matrix, and showing an optimal nanoparticle loading around 2 vol%. The scratch resistance of the nanocomposites obtained from hydrophilic silicas was investigated, and a remarkable enhancement in the indenter's penetration resistance was observed for all the compositions with respect to pristine PC. The same behaviour was observed for the Shore D hardness and for the impact resistance of the nanocomposites that also significantly improved with the maximum load shifting from a minimum value of 521 N for pristine PC up to values grater than 1330 N for the nanocomposites, demonstrating the activation of effective mechanisms of energy dissipation due to the presence of the nanofillers. [ABSTRACT FROM AUTHOR]

Zirconia nanoparticles were synthesized by a sol-gel route and dispersed into an epoxy base for structural adhesives. Nanoparticles were used as-synthesized or after calcination. Moreover, the effect of silane functionalization was also investigated. According to preliminary tensile mechanical tests on bulk nanocomposite samples, calcined and untreated zirconia nanoparticles were selected for the preparation of adhesives with various filler contents. The glass transition temperature increased up to a filler content of 1 vol% and then decreased, probably due to the concurrent and contrasting effects of chain blocking and reduction of the crosslinking degree. Also tensile modulus, stress at break and fracture toughness of bulk adhesives samples were positively affected by the presence of an optimal amount of zirconia nanoparticles. Mechanical tests on single lap aluminium bonded joints indicated that zirconia nanoparticles led to relevant enhancements of the shear strength of the joints. In particular, the shear strength increased by about 60% for an optimal filler content of 1 vol%, and an adhesive failure mechanism was evidenced for all the tested specimens. Concurrently, a significant decrease of the equilibrium contact angle with water was observed for adhesives containing zirconia nanoparticles. It can therefore be concluded that the addition of zirconia nanoparticles can effectively improve epoxy adhesives, both by increasing their mechanical properties and by enhancing the interfacial wettability with an aluminium substrate. [ABSTRACT FROM AUTHOR]

The article presents a study which used acicular titania nanoparticles to prepare nanocomposites filled at varying concentrations by melt mixing with a high density polyethylene (HDPE) matrix. The study found a decrease in the creep compliance for both the elastic and viscous components. The researchers recommended using untreated titania nanoparticles in reducing the creep compliance rather than the functionalized ones.

Poly(thiodiethylene terephthalate) (PSDET), poly(thiodiethylene adipate) (PSDEA), poly(diethylene terephthalate) (PDET) and poly(diethylene adipate) (PDEA) for comparison were synthesized and characterized in terms of chemical structure and molecular weight. The thermal behavior was examined by thermo gravimetric analysis and differential scanning calorimetry. All the polymers showed a good thermal stability, even though lower for the sulfur-containing polyesters. At room temperature they appeared as semicrystalline materials, except PDEA, which was an oil; the effect of substitution of ether oxygen atoms with sulfur ones was a lowering in the Tg value, an increment of melting temperature and an increase of crystallization rate. The results were explained as due to the presence of flexible C-S-C bonds in the polymeric chain. [ABSTRACT FROM AUTHOR]

Copyright of Surface Coatings International Part B: Coatings Transactions is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Surface Coatings International Part B: Coatings Transactions is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Surface Coatings International Part B: Coatings Transactions is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hepatic synthesis of lipoproteins and apolipoproteins was investigated in male Wistar rats with severe nephrotic syndrome induced by puromycin aminonucleoside by incubating liver slices with a mixture ofC-amino acids. Labeled lipoproteins were separated by preparative ultracentrifugation from the incubation medium after the addition of carrier plasma. The incorporation ofC-amino acids into very low density lipoproteins (VLDL) (1.006 g/ml), low density lipoproteins (LDL) (1.006-1.063 g/ml) and high density lipoproteins (HDL) (1.063-1.210 g/ml) was increased in nephrotic liver 6.1-, 5.7- and 5.0-fold, respectively. The measurement of radioactivity associated to apolipoproteins isolated by SDS-PAGE documented an increased incorporation into apolipoprotein E (apoE) of nephrotic VLDL (33.1% vs 20% of the total radioactivity incorporated into VLDL apoproteins) and a markedly increased incorporation into apolipoprotein A-I (apoA-I) of nephrotic HDL (44.3% vs 16.3% of the total radioactivity incorporated into HDL apoproteins). In nephrotic liver, the total incorporation of amino acids into apolipoproteins (apoVLDL+apoLDL+apoHDL) was increased 12.6 times for apoA-I, 6.4 times for apoB, 5.0 times for apoE, 4.2 times for apoC+apoA-II and 2.5 times for apoA-IV. We suggest that, in nephrotic liver: (a) the synthesis of VLDL, LDL and HDL is increased, and (b) the total synthesis of apoA-I is selectively increased when compared to that of the other apolipoproteins. [ABSTRACT FROM AUTHOR]