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Increased recycling of plastics is an essential step toward a more sustainable use of materials, where some of the most challenging fractions are engineering materials and composites. Used pump houses prepared from glass fiber (GF)‐reinforced blends of polyphenylene oxide (PPO) and high‐impact polystyrene (HIPS) obtained through a take‐back scheme (take‐back, TB) were characterized and shredded for use in the preparation of new composites by injection molding. Initial degradation was observed on the surface of the TB parts; however, the core of the material was unaffected. Mechanical reprocessing of regrind and virgin material showed a reduction of tensile strength already at 10% regrind, which was attributed to fiber length reduction during reprocessing. At the same time, Young's modulus and extension at break were largely unaffected, confirming that 25% of TB could be included without any additional loss of properties. As a worst‐case scenario, tests with extensively degraded material showed that Young's modulus and tensile strength would ultimately be reduced with an increasing amount of heavily degraded material and that a balance would have to be found between loss of properties and recycled content for heavily degraded material. [ABSTRACT FROM AUTHOR]

Background: Hydroxyurea (HU) is a commonly used first‐line treatment in patients with polycythemia vera (PV). However, approximately 15%–24% of PV patients report intolerance and resistance to HU. Methods: This phase IV, European, real‐world, observational study assessed the efficacy and safety of ruxolitinib in PV patients who were resistant and/or intolerant to HU, with a 24‐month follow‐up. The primary objective was to describe the profile and disease burden of PV patients. Results: In the 350 enrolled patients, 70% were >60 years old. Most patients (59.4%) had received ≥1 phlebotomy in the 12 months prior to the first dose of ruxolitinib. Overall, 68.2% of patients achieved hematocrit control with 92.3% patients having hematocrit <45% and 35.4% achieved hematologic remission at month 24. 85.1% of patients had no phlebotomies during the study. Treatment‐related adverse events were reported in 54.3% of patients and the most common event was anemia (22.6%). Of the 10 reported deaths, two were suspected to be study drug‐related. Conclusion: This study demonstrates that ruxolitinib treatment in PV maintains durable hematocrit control with a decrease in the number of phlebotomies in the majority of patients and was generally well tolerated. [ABSTRACT FROM AUTHOR]

Objective: To estimate the cumulative incidences of orofacial conditions related to temporomandibular joint (TMJ) juvenile idiopathic arthritis (JIA) between diagnosis in childhood to transition into adult care, and to identify features in JIA associated with TMJ involvement. Methods: A population‐based cohort analysis was conducted of patients with JIA involving longitudinal data on orofacial health from 2000 to 2018. Regardless of TMJ status, the patients were referred to the Regional Specialist Craniofacial Clinic of Western Denmark for routine orofacial examinations. Data collection included information about disease‐specific background characteristics, TMJ involvement, JIA‐induced dentofacial deformity, and orofacial symptoms and dysfunction. Results: A total of 613 patients were followed up with a mean clinical TMJ observation time of 4.0 years. From JIA onset to transition into adult care, the cumulative incidence of patients with JIA involvement of the TMJ was 30.1%. Furthermore, 20.6% of the cohort had developed arthritis‐induced dentofacial deformity. A substantial proportion of the cohort experienced several events with orofacial symptoms (23.5%) and dentofacial dysfunction (52%). Young age at diagnosis (<9 years), female gender, and antinuclear antibody positivity were significantly associated with TMJ involvement. Conclusion: Orofacial signs and symptoms were frequent findings in children and adolescents with JIA. TMJ involvement was seen in 30.1% of the cohort; and 20.6% of the total cohort developed JIA‐related dentofacial deformity before transition into adult care. This is the first population‐based study in the era of available biologic treatments to document these frequent orofacial complications in children with JIA. [ABSTRACT FROM AUTHOR]

Electrophilic groups are one of the key pillars of contemporary chemical biology and medicinal chemistry. For instance, 3‐membered N‐heterocyclic compounds—such as aziridines, azirines, and oxaziridines—possess unique electronic and structural properties which underlie their potential and applicability as covalent tools. The α‐lactams are also members of this group of compounds, however, their utility within the field remains unexplored. Here, we demonstrate an α‐lactam reagent (AM2) that is tolerant to aqueous buffers while being reactive towards biologically relevant nucleophiles. Interestingly, carboxylesterases 1 and 2 (CES1/2), both serine hydrolases with key roles in endo‐ and xenobiotic metabolism, were found as primary covalent targets for AM2 in HepG2 liver cancer cells. All in all, this study constitutes the starting point for the further development and exploration of α‐lactam‐based electrophilic probes in covalent chemical biology. [ABSTRACT FROM AUTHOR]

Fatty liver disease has mainly been characterized under fasting conditions. However, as the liver is essential for postprandial homeostasis, identifying postprandial disturbances may be important. Here, we investigated postprandial changes in markers of metabolic dysfunction between healthy individuals, obese individuals with non‐alcoholic fatty liver disease (NAFLD) and patients with cirrhosis. We included individuals with biopsy‐proven NAFLD (n = 9, mean age 50 years, mean BMI 35 kg/m2, no/mild fibrosis), cirrhosis with hepatic steatosis (n = 10, age 62 years, BMI 32 kg/m2, CHILD A/B) and healthy controls (n = 10, age 23, BMI 25 kg/m2), randomized 1:1 to fasting or standardized mixed meal test (postprandial). None of the patients randomized to mixed meal test had type 2 diabetes (T2D). Peripheral blood was collected for 120 min. After 60 min, a transjugular liver biopsy and liver vein blood was taken. Plasma levels of glucose, insulin, C‐peptide, glucagon, and fibroblast growth factor 21 (FGF21) were measured. Postprandial peak glucose and C‐peptide were significantly increased in NAFLD, and cirrhosis compared with healthy. Patients with NAFLD and cirrhosis had hyperglucagonemia as a potential sign of glucagon resistance. FGF21 was increased in NAFLD and cirrhosis independent of sampling from the liver vein versus peripheral blood. Glucagon levels were higher in the liver vein compared with peripheral blood. Patients with NAFLD and cirrhosis without T2D showed impaired glucose tolerance, hyperinsulinemia, and hyperglucagonemia after a meal compared to healthy individual. Postprandial characterization of patients with NAFLD may be important to capture their metabolic health. [ABSTRACT FROM AUTHOR]

Glass fiber (GF) composites are one of the significant challenges in recycling thermoset materials. After pyrolysis, the glass fibers lack sufficient strength and show poor matrix compatibility. Here we have investigated a series of multifunctional silane and silazane agents for surface modification of recycled glass fibers that provide a combination of hydrophobic properties and residual reactive groups on the surface. This allowed testing of interfacial effects from the surface modification as well as a potential synergistic compatibilization using maleated PP (MAPP). The treated GFs were used to prepare new polypropylene (PP) composites by multiple extrusion steps, resulting in a series of composites where the dispersion efficiency was attributed mainly to the surface chemistry and compatibilization effects. The amino‐silane modifications of the recycled fibers resulted in further improvements in the mechanical properties of the PP composites in comparison with the hydrophobized GFs. Moreover, synergistic effects from the addition of MAPP were observed with scanning electron microscopy. The results clearly demonstrate that the surface modifications were effective and good alternatives to currently used methods. [ABSTRACT FROM AUTHOR]

Silicones are typically cured at room temperature by means of metal catalyst such as tin or platinum. When networks are formed, the catalyst becomes unrecoverable, which is of economic as well as environmental concern. Very few methods for producing metal catalyst‐free room‐temperature‐vulcanized (RTV) silicones exist and require conditions unavailable in industrial settings. Through the study of organic polysilazane (PSz) reactivity with simple alcohols by nuclear magnetic resonance, an unexpected fragmentation preference is discovered for breaking the SiN bond rather than the SiH; thereby, casting a new light on the fragmentation mechanism of PSzs. Utilizing the PSz fragmentation as a silyl ether coupling agent for multifunctional carbinol silicones, a method of producing catalyst‐free RTV silicone networks at ambient conditions is presented. These silicone networks are proven chemically similar to a standard condensation‐cured silicone and stoichiometric variations of PSz content demonstrate adjustable network properties. [ABSTRACT FROM AUTHOR]

While alloying is a powerful handle for materials engineering, it is an ongoing challenge to navigate the large and complex parameter space of these materials. This applies in particular for thermoelectrics and even more so clathrates. Here, a combination of density functional theory calculations, alloy cluster expansions, Monte Carlo simulations, and Boltzmann transport theory calculations is used to identify compositions that yield high power factors in the pseudo‐ternary clathrates Ba8AlxGayGe46−x−y and Ba8GaxGeySi46−x−y, while accounting for weight and raw material costs. The results show how a cost‐efficient performance can be achieved by reducing the number of Al and Ga atoms per unit cell, while compensating the resulting increase in the carrier concentration via an extrinsic dopant. The approach used in this study is transferable and can be a useful tool for mapping the thermodynamic and transport properties of other multinary systems. [ABSTRACT FROM AUTHOR]

Antibacterial surfaces have been researched for more than 30 years and remain highly desirable. In particular, there is an interest in providing antimicrobial properties to commodity plastics, because these, in their native state, are excellent substrates for pathogens to adhere and proliferate on. Therefore, efficient strategies for converting surfaces of commodity plastics into contact‐active antimicrobial surfaces are of significant interest. Many systems have been prepared and tested for their efficacy. Here, the synthetic approaches to such active surfaces are reviewed, with the restriction to only include systems with tested antibacterial properties. The review focuses on the synthetic approach to surface functionalization of the most common materials used and tested for biomedical applications, which effectively has limited the study to quaternary materials. For future developments in the field, it is evident that there is a need for development of simple methods that permit scalable production of active surfaces. Furthermore, in terms of efficacy, there is an outstanding concern of a lack of universal antimicrobial action as well as rapid deactivation of the antibacterial effect through surface fouling. [ABSTRACT FROM AUTHOR]

BACKGROUND: Oxidation is among the most important reactions in organic chemistry. Enzymatic oxidation offers a greener alternative to a conventional chemo‐catalytic approach and opens the potential for new reactions. However, inefficient use of expensive enzymes and oxygen (O2) limitations represent particular challenges for biocatalytic reactor design. This work reports a new tubular reactor for continuous flow enzymatic oxidations. RESULTS: The reactor comprises a thiol‐functional porous monolith (0.93 ± 0.16 m2 g−1) and an O2‐permeable wall (115 600 ± 1500 mL m−2 day−1). The monolith retains enzyme inside the reactor leading to efficient use. The wall acts as a membrane contactor providing transport of O2 from atmospheric air to the immediate proximity of the enzyme inside the reactor, without any pressure and sparging required. The reactor performance was demonstrated using oxidation of glucose by glucose oxidase (EC 1.1.3.4) coupled with in situ consumption of hydrogen peroxide by horseradish peroxidase (EC 1.11.1.7). At a constant flow rate of 0.1 mL min−1, the product concentration reached 0.10 mmol L−1 after 1.5 h and continued to be relatively high for the next ≥10 h. Overall, the reactor remained active for >40 h using only 15 μg glucose oxidase. Furthermore, the reactor could be rejuvenated by periodic injection of fresh enzyme and thus can operate continuously for extended periods. CONCLUSION: We have shown here an alternative approach to efficient enzyme use and O2 delivery. Moreover, with its flexible design, the reactor can be optimized to accommodate a range of gas‐dependent biocatalytic transformations. © 2021 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Mold preparation, material layup, and cure times for thermoset‐based composites often limit their use in high‐volume applications. As such, new rapid cure epoxy resins are being developed to achieve a complete cycle time within 3 min. In this research, calorimetry and rheometry are used to examine and model two novel rapid cure epoxy resin systems with internal mold release. The rapid cure epoxy resins followed an autocatalytic cure kinetic and William–Landel–Ferry diffusion model. The rapid cure epoxy resin was shown to achieve 94% cure in 2 min at 150°C. However, adding an additional 2.5 wt% internal mold release hindered the first step of the reaction, which delayed the second reaction step since the final degrees of cure were similar. Furthermore, the resin viscosity followed a modified William–Landel–Ferry equation and at 120°C could maintain a viscosity below 5 Pa s for 4.1 min. These models provided valuable insight into the range of processing conditions these novel resins could experience during impregnation and molding processes. [ABSTRACT FROM AUTHOR]

Type‐I inorganic clathrates are promising high temperature thermoelectric materials. They are known for their intrinsic low thermal conductivity, but a moderate power factor leaves room for further improvement. In this paper, a new route for improving the power factor by enhanced carrier mobility achieved via modulation doping is reported. A series of clathrates with composition Ba8(AlxGa1−x)16Ge30 are synthesized through ball milling and spark plasma sintering of mixtures of Ba8Al16Ge30 and Ba8Ga16Ge30. Among the materials with x = 0.20, 0.23, and 0.25, it is found that the electrical conductivity is significantly enhanced with increasing x, while the Seebeck coefficient decreases slightly. It is further revealed that the carrier mobility of the sintered sample x = 0.25 is greatly increased, reaching a value that exceeds that for a single crystal. Electron microscopy analysis reveals that the material consists of a heterostructure and is composed of a Ga‐rich clathrate matrix phase and Al particles, suggesting that the power factor enhancement is due to modulation doping. As a result, the highest power factor is achieved for Ba8(Al0.25Ga0.75)16Ge30, with a value of 1.89 mW m−1 K−2 at 800 °C. Consequently, the maximum zT of sample x = 0.25 reaches 0.93 at 800 °C. [ABSTRACT FROM AUTHOR]

A method for grafting lithium sulfonate (LiSO3) groups to carbon surfaces is developed and the resulting carbons are evaluated for their potential to reduce the lithium polysulfide (LiPS) shuttle in lithium–sulfur (Li–S) batteries, replacing the common electrolyte additive lithium nitrate (LiNO3). The LiSO3 groups are attached to the ordered mesoporous carbon (CMK3) surface via a three‐step procedure to synthesize LiSO3‐CMK3 by bromomethylation, sodium sulfite (Na2SO3) substitution, and cation exchange. As a comparison, ethylenediamine (EN)‐substituted CMK3, EN‐CMK3, is also synthesized and tested. When used as a cathode in Li–S batteries, the unfunctionalized CMK3 suffers from strong LiPS shuttling as evidenced by its low initial Coulombic efficiencies (ICEs, <10%) compared to its functionalized derivatives EN‐CMK3 and LiSO3‐CMK3 (ICEs >75%). Postcycling analysis reveals the benefits of cathode surface functionalization on the lithium anode via an attenuated LiPS shuttle. When monitored at open circuit, the functionalized cathodes maintain their cell voltages much better than the CMK3 control and concurrent electrochemical impedance spectroscopy reveals their higher total cell resistance, which provides evidence for a reduced LiPS shuttle in the vicinity of both electrodes. Overall, such surface groups show promise as cathode‐immobilized "lithium nitrate mimics." [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries are of great interest due to their potentially high energy density, but the low electronic conductivity of both the sulfur (S8) cathode active material and the final discharge product lithium sulfide (Li2S) require the use of a conductive host. Usually made of relatively hydrophobic carbon, such hosts are typically ill‐suited to retain polar discharge products such as the intermediate lithium polysulfides (LiPs) and the final Li2S. Herein, we propose a route to increase the sulfur utilization by functionalizing the surface of ordered mesoporous carbon CMK3 with polar groups. These derivatized CMK3 materials are made using a simple two‐step procedure of bromomethylation and subsequent nucleophilic substitution with amine or amide nucleophiles. We demonstrate that, compared to the unfunctionalized control, these modified CMK3 surfaces have considerably larger binding energies with LiPs and Li2S, which are proposed to aid the electrochemical conversion between S8 and Li2S by keeping the LiPs species in close proximity to the carbon surface during Li–S battery cycling. As a result, the functionalized cathodes exhibit significantly improved specific capacities relative to their unmodified precursor. [ABSTRACT FROM AUTHOR]

Objective: To estimate the cumulative incidence of arthritis-induced orofacial symptoms, dysfunction, and dentofacial deformities in growing individuals with juvenile idiopathic arthritis (JIA) in a 36-month regional cohort study and to identify predictors for the development of arthritis-induced dentofacial deformities.Methods: Data were retrieved from the Aarhus JIA temporomandibular joint (TMJ) cohort register, which contains standardized, longitudinal, observational data regarding orofacial conditions in patients with JIA (n = 1,040). This regional cohort represents the majority of all subjects with JIA from the western part of Denmark between 1990 and 2016, regardless of TMJ arthritis status. Cumulative incidences of orofacial conditions were reported using Kaplan-Meier methods, and predictors for dentofacial deformity were identified using Cox proportional hazards analysis.Results: Follow-up data from 351 subjects for 36 months were included in this study. Median age at first clinical examination was 6.6 years (interquartile range 4.8-9.9 years). Orofacial symptoms and dysfunctions were common findings at 36 months after the first clinical examination and 5 years after JIA onset, with a cumulative incidence of 38% and 53%, respectively. Dentofacial deformities were found in 35% of subjects at the 36-month follow-up and were significantly associated with the presence of orofacial dysfunction.Conclusion: Orofacial conditions were frequently observed in individuals with JIA and were represented in all JIA subcategories in this regional study. One-third of subjects had arthritis-induced dentofacial deformities that required orthopedic appliance treatment at the 36-month follow-up. [ABSTRACT FROM AUTHOR]

BACKGROUND: Purification of polyhydroxyalkanoates (PHA) is a challenging step, given the difficulty of achieving high PHA purity, while maintaining polymer integrity, in a sustainable and cost‐efficient manner. This study evaluated the potential of dilute ammonia digestion as a method to purify PHA from mixed microbial consortia. RESULTS: Digestion temperatures were critical to the obtainable purity and the amount of recovered PHA. At temperatures below 75 °C (regardless of the incubation time and ammonia concentration), a low PHA recovery (down to 65%) and no increase in purity was observed. By increasing the temperature above 75 °C, a significantly higher PHA purity and higher recovery (above 90%) could be achieved. Temperatures maximizing the purity (140 °C) led to a detrimental reduction in the molar mass of the isolated PHA, but the use of a sonication pre‐treatment enabled to increase the purity at temperatures leading to limited molar mass loss (75–115 °C). The impurities still present in the recovered PHA did not compromise its thermal stability, and no significant degradation occurred during melting of PHA with 86% purity (comparably to pure chloroform‐extracted PHA). Conversely, PHA recovered through sulphuric acid (H2SO4) digestion underwent severe degradation during melting, despite presenting higher purity (98%). CONCLUSIONS: High PHA purity, recovery and thermal stability can be obtained with dilute ammonia digestion. These observations, combined with the possibility of reusing ammonia within the process, make this method a promising approach for a more sustainable purification of PHA. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

We present how the microenvironment can directly improve biocatalytic selectivity of immobilized ß-glucosidase. ß-Glucosidase from Thermotoga neapolitana was immobilized on a variety of functionalized off-stoichiometric thiol-ene (OSTE) particles, where highest activities were observed for thiol and imidazole functional particles. Compared to the soluble enzyme, the selectivity (rs/rh) between trans-glycosylation of p-nitrophenyl β-D-glucopyranoside (pNPG) with 1-propanol over hydrolysis was increased by a factor of 2-3 using particles containing imidazole (rs/rh of 6.7) and carboxylic acid moieties (rs/rh of 9.2), respectively. These results demonstrate clearly that enzyme selectivity depends directly on the local environment of the enzyme with the support. [ABSTRACT FROM AUTHOR]

Summary: Amplicon sequencing of the 16S rRNA gene is the predominant method to quantify microbial compositions and to discover novel lineages. However, traditional short amplicons often do not contain enough information to confidently resolve their phylogeny. Here we present a cost‐effective protocol that amplifies a large part of the rRNA operon and sequences the amplicons with PacBio technology. We tested our method on a mock community and developed a read‐curation pipeline that reduces the overall read error rate to 0.18%. Applying our method on four environmental samples, we captured near full‐length rRNA operon amplicons from a large diversity of prokaryotes. The method operated at moderately high‐throughput (22286–37,850 raw ccs reads) and generated a large amount of putative novel archaeal 23S rRNA gene sequences compared to the archaeal SILVA database. These long amplicons allowed for higher resolution during taxonomic classification by means of long (∼1000 bp) 16S rRNA gene fragments and for substantially more confident phylogenies by means of combined near full‐length 16S and 23S rRNA gene sequences, compared to shorter traditional amplicons (250 bp of the 16S rRNA gene). We recommend our method to those who wish to cost‐effectively and confidently estimate the phylogenetic diversity of prokaryotes in environmental samples at high throughput. [ABSTRACT FROM AUTHOR]

Nonisothermally fusion bonded butt joints were prepared by overmolding thermoplastic elastomers (TPEs) onto isotactic polypropylene (iPP) inserts in order to investigate the effect of processing conditions on the bond strength and interfacial microstructure. The mold temperature (Tm) was the most important factor for bond strength, as determined from interfacial mechanical tests. Extensive melting and recrystallization took place at the surface of the iPP insert at high Tm, promoted by migration of plasticizer from the TPE, whereas the original structure of the iPP remained intact at low Tm. Bond strengths of at least 50% of the cohesive strength of the TPE were nevertheless obtained at low Tm, suggesting intimate contact between the TPE melt and the iPP surface to be sufficient to provide useful adhesive bond strengths in these materials. The influence of pressure was less marked than the Tm, high pressures not being necessary to achieve intimate contact for the bonding times of about 5 s used here. However, the combination of a low bonding pressure with a high Tm typically led to poor quality bonds in thick specimens owing to uncompensated shrinkage during solidification, and voiding at the interface and in the melt zone of the iPP insert. POLYM. ENG. SCI., 58:E82–E92, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Thiol-ene (TE)-based polymer particles are traditionally prepared via emulsion polymerization in water (using surfactants, stabilizers, and cosolvents). Here, a green and simple alternative is presented with excellent control over particle size, while avoiding the addition of stabilizers. Glycerol is applied as a dispersing medium for the preparation of off-stoichiometric TE microparti-cles, where sizes in the range of 40-400 µm are obtained solely by changing the mixing speed of the emulsions prior to crosslinking. Control over surface chemistry is achieved by surface functionalization of excess thiol groups via photochemical thiol-ene chemistry resulting in a functional monolayer. In addition, surface chain transfer free radical polymerization is used for the first time to introduce a thicker polymer layer on the particle surface. The application potential of the system is demonstrated by using functional particles as adsorbent for metal ions and as a support for immobilized enzymes. [ABSTRACT FROM AUTHOR]

Efficient immobilization of enzymes on support surfaces requires an exact match between the surface chemistry and the specific enzyme. A successful match would normally be identified through time consuming screening of conventional resins in multiple experiments testing individual immobilization strategies. In this study we present a versatile strategy that largely expands the number of possible surface functionalities for enzyme immobilization in a single, generic platform. The combination of many individual surface chemistries and thus immobilization methods in one modular system permits faster and more efficient screening, which we believe will result in a higher chance of discovery of optimal surface/enzyme interactions. The proposed system consists of a thiol-functional microplate prepared through fast photochemical curing of an off-stoichiometric thiol-ene (OSTE) mixture. Surface functionalization by thiol-ene chemistry (TEC) resulted in the formation of a functional monolayer in each well, whereas, polymer surface grafts were introduced through surface chain transfer free radical polymerization (SCT-FRP). Enzyme immobilization on the modified surfaces was evaluated by using a rhodamine labeled horseradish peroxidase (Rho-HRP) as a model enzyme, and the amount of immobilized enzyme was qualitatively assessed by fluorescence intensity (FI) measurements. Subsequently, Rho-HRP activity was measured directly on the surface. The broad range of utilized surface chemistries permits direct correlation of enzymatic activity to the surface functionality and improves the determination of promising enzyme-surface candidates. The results underline the high potential of this system as a screening platform for synergistic immobilization of enzymes onto thiol-ene polymer surfaces. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1267-1277, 2017 [ABSTRACT FROM AUTHOR]

ABSTRACT Conductive elastomers based on MWCNT in polydimethylsiloxane (PDMS) have been prepared by a range of dispersion methods such as ultrasonication, speedmixing and roll milling in combination with physical or covalent modification. The ionic liquid (IL), 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, was used to pre-disperse MWCNT in a MWCNT/IL-gel that was used for preparation of MWCVNT/PDMS composites. The method was seen to be effective at low levels of MWCNT, but required combination with a roll mill to obtain a stable dispersion at 4 wt % MWCNT. With higher amounts of MWCNT a reduction in conductivity was observed, which was attributed to a change in morphology occurring between 4 and 5 wt % MWCNT. As an alternative to IL dispersing aids a novel functionalized MWCNT was prepared by free radical polymerization using α-methacryloxypropyl-polydimethylsiloxane, which could be used directly for preparation of MWCNT/PDMS composites. Composites prepared by use of the IL dispersion method, use of a roll mill or by use of the f-MWCNT all had conductivities around 0.005-0.01 s/cm and retained conductivity upon extension. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44767. [ABSTRACT FROM AUTHOR]

The characteristics and precipitation mechanism of particles in titanium- and aluminum-treated Hadfield steel casted during pilot-scale experiments have been studied. Light Optical Microscopy (LOM), Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray Spectroscopy (EDS) are utilized for the particle analysis and characterization. Additionally, thermodynamic equilibrium calculations are performed using Thermo-Calc software. Aluminum oxides, titanium carbon nitrides, titanium carbides, and manganese sulfides are the main types of particles found. The order of precipitation during solidification and chemical composition range of each type of particle are determined. Aluminum oxides are found to act as nucleation sites for titanium carbon nitrides. Thermodynamic equilibrium calculations for particles characteristics are in good agreement with the experimental findings. Titanium carbides are found to form during initial stages of the ferro-titanium additions dissolution. [ABSTRACT FROM AUTHOR]

Poly(lactic acid) ( PLA)-based hybrid nanocomposites ( PLA, nanoclay and nanocellulose) were prepared by reinforcing neat PLA with commercially available nanoclay (Cloisite C30B) and nanocellulose, in the form of either partially acetylated cellulose nanofibres ( CNFs) or nanocrystalline cellulose. Composites with 1 or 5 wt% of nanocellulose, in combination with 1, 3 and 5 wt% of nanoclay, were prepared, and their barrier properties were investigated. It was found that the combination of clay and nanocellulose clearly resulted in synergistic behaviour in terms of the oxygen transmission rate ( OTR) through a reduction of up to 90% in OTR and a further reduction in the water vapour transmission rate of up to 76%. In addition, the nanocomposite films showed improved thermomechanical resistance and improved crystallisation kinetics while maintaining high film transparency. This makes the hybrid PLA/ CNF/ C30B nanocomposites a very promising material for food packaging applications. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

This paper aims to investigate the effect of Si-content and microstructure on mechanical properties of Al-Si-Mg alloys with the purpose of to develop high-strength cast aluminum alloys that are anodizable. The Si-content was 2.5, 3.5 and 5.5wt% Si, and both Sr-modified and unmodified conditions were used. The samples were produced using the gradient solidification furnace to generate awell-controlled microstructure. The resulting secondary dendrite armspacingwas 10 and 20μm. Themicrostructural features were evaluated by employing SEM/EDS and optical microscopy. Furthermore, computed tomography (CT) scan technology was used to provide a 3D view of high-density phases in the microstructure. The mechanical properties of these alloys were studied by means of tensile and hardness testing where the latter was performed on the macrolevel and microlevel. The results demonstrate clearly how the Si growth in the microstructure is restricted by increased cooling rate and modification and its role in strength development in Al-Si alloys. Additionally, the CT scan visualized the morphology of intermetallics and supported in identifying the oxide layer growth as a result of the anodizing process. [ABSTRACT FROM AUTHOR]

Silicone elastomers are promising materials for dielectric elastomer transducers (DETs) due to their superior properties such as high efficiency, reliability and fast response times. DETs consist of thin elastomer films sandwiched between compliant electrodes, and they constitute an interesting class of transducer due to their inherent lightweight and potentially large strains. For the field to progress towards industrial implementation, a leap in material development is required, specifically targeting longer lifetime and higher energy densities to provide more efficient transduction at lower driving voltages. In this review, the current state of silicone elastomers for DETs is summarised and critically discussed, including commercial elastomers, composites, polymer blends, grafted elastomers and complex network structures. For future developments in the field it is essential that all aspects of the elastomer are taken into account, namely dielectric losses, lifetime and the very often ignored polymer network integrity and stability. [ABSTRACT FROM AUTHOR]

The total synthesis of the resveratrol dimers (±)-ampelopsin B and (±)-ϵ-viniferin is reported. Highlights of the approach include the use of cyclopropylmethyl groups to protect aromatic alcohols. This group allows an acid promoted three-step, one-pot deprotection-epimerization-cyclization of an advanced intermediate to give (±)-ampelopsin B. An important advantage with our strategy is the possibility of synthesizing analogs to these natural products to further study the chemistry and biology of resveratrol oligomers. [ABSTRACT FROM AUTHOR]

ABSTRACT Human cytomegalovirus (HCMV) causes significant disease worldwide. Multiple HCMV vaccines have been tested in man but only partial protection has been achieved. The HCMV gH/gL/UL128/UL130/UL131A complex (Pentamer) is the main target of neutralizing antibodies in HCMV seropositive individuals and raises high titers of neutralizing antibodies in small animals and non-human primates (NHP). Thus, Pentamer is a promising candidate for an effective HCMV vaccine. Development of a Pentamer-based subunit vaccine requires expression of high amounts of a functional and stable complex. We describe here the development of a mammalian expression system for large scale Pentamer production. Several approaches comprising three different CHO-originated cell lines and multiple vector as well as selection strategies were tested. Stable cell pools expressed the HCMV Pentamer at a titer of approximately 60 mg/L at laboratory scale. A FACS-based single cell sorting approach allowed selection of a highly expressing clone producing Pentamer at the level of approximately 400 mg/L in a laboratory scale fed-batch culture. Expression in a 50 L bioreactor led to the production of HCMV Pentamer at comparable titers indicating the feasibility of further scale-up for manufacturing at commercial scale. The CHO-produced HCMV Pentamer bound to a panel of human neutralizing antibodies and raised potently neutralizing immune response in mice. Thus, we have generated an expression system for the large scale production of functional HCMV Pentamer at high titers suitable for future subunit vaccine production. Biotechnol. Bioeng. 2015;112: 2505-2515. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Background and Aim The impaired glucose tolerance in cirrhosis is poorly understood. We evaluated the influence of gastrointestinal-mediated glucose disposal and incretin effect in patients with cirrhosis. Methods Non-diabetic patients with Child- Pugh A or B cirrhosis ( n = 10) and matched healthy controls ( n = 10) underwent a 50-g oral glucose tolerance test ( OGTT) and an isoglycemic intravenous glucose infusion. We presented data as median ± interquartile range and compared groups using non-parametric analysis of variance. Results Patients with cirrhosis were glucose intolerant compared with healthy controls (4-h OGTTAUC: 609 ± 458 vs 180 ± 155 min × mmol/L; P = 0.005), insulin resistant (homeostatic model assessment for insulin resistance: 3.7 ± 4.9 vs 2.6 ± 1.4; P = 0.014) and had fasting hyperglucagonemia (8 ± 3 vs 3 ± 4 pmol/L; P = 0.027). Isoglycemia was achieved using 35 ± 12 g of intravenous glucose in patients with cirrhosis compared with 24 ± 10 g in healthy controls ( P = 0.003). The gastrointestinal-mediated glucose disposal was markedly lower in patients with cirrhosis (30 ± 23 vs 52 ± 20%; P = 0.003). Despite higher levels of the incretin hormones glucagon-like peptide-1 and glucose-dependent insulinotropic peptide patients with cirrhosis had reduced incretin effect (35 ± 44 vs 55 ± 30%; P = 0.008). Conclusion Impaired gastrointestinal-mediated glucose disposal and reduced incretin effect may contribute to the glucose intolerance seen in patients with cirrhosis. [ABSTRACT FROM AUTHOR]

Watch and wait ( WAW) is a common approach for asymptomatic, advanced stage follicular lymphoma ( FL), but single-agent rituximab is an alternative for these patients. In this nationwide study we describe the outcome of patients selected for WAW. A cohort of 286 out of 849 (34%) stage III- IVA FL patients seen between 2000 and 2011, were managed expectantly and included. The 5-year progression-free survival ( PFS) was 35% [95% confidence interval ( CI) 29-42]. The 10-year overall survival ( OS) was 65% (95% CI 54-78), and the cumulative risk of dying from lymphoma within 10 years of diagnosis was 13% (95% CI 7-20). Elevated lactate dehydrogenase and > four nodal regions involved were associated with a higher risk of lymphoma treatment and death from lymphoma. The WAW patients and a matched background population had similar OS during the first 50 months after diagnosis ( P = 0·7), but WAW patients had increased risk of death after 50 months ( P < 0·001). The estimated loss of residual life after 10 years was 6·8 months. The 10-year cumulative risk of histological transformation was 22% (95% CI 15-29) and the 3-year OS after transformation was 71% (95% CI 58-87%). In conclusion, advanced stage FL managed by WAW had a favourable outcome and abandoning this strategy could lead to overtreatment in some patients. [ABSTRACT FROM AUTHOR]

Cylindrical critical size defects were created at the distal femoral condyles bilaterally of eight female adult sheep. Titanium implants with 2-mm concentric gaps were inserted and the gaps were filled with one of the four materials: allograft; a synthetic 15-amino acid cell-binding peptide coated hydroxyapatite (ABM/P-15); hydroxyapatite + βtricalciumphosphate+ Poly-Lactic-Acid (HA/βTCP-PDLLA); or ABM/P-15+HA/βTCP-PDLLA. After nine weeks, bone-implant blocks were harvested and sectioned for micro-CT scanning, push-out test, and histomorphometry. Significant bone formation and implant fixation could be observed in all four groups. Interestingly, the microarchitecture of the ABM/P-15 group was significantly different from the control group. Tissue volume fraction and thickness were significantly greater in the ABM/P-15 group than in the allograft group. Bone formation and bone ingrowth to porous titanium implant were not significantly different among the four groups. The ABM/P-15 group had similar shear mechanical properties on implant fixation as the allograft group. Adding HA/βTCP-PDLLA to ABM/P-15 did not significantly change these parameters. This study revealed that ABM/P-15 had significantly bone formation in concentric gap, and its enhancements on bone formation and implant fixation were at least as good as allograft. It is suggested that ABM/P-15 might be a good alternative biomaterial for bone implant fixation in this well-validated critical-size defect gap model in sheep. Nevertheless, future clinical researches should focus on prospective, randomized, controlled trials in order to fully elucidate whether ABM/P-15 could be a feasible candidate for bone substitute material in orthopedic practices. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 1357-1365, 2015. [ABSTRACT FROM AUTHOR]

In this study, we demonstrate by simulation and experiment the antireflective (AR) performance of hyperbranched polymer (HBP) nanocomposites textures replicated from a moth-eye pattern using ultraviolet (UV) nanoimprint lithography. A UV-curable acrylated HBP and a hybrid composite of the HBP with silica nanoparticles with an organometal precursor were used. Using effective medium theory (EMT) simulations, optimal patterns were found to be arrays of paraboloids with stable AR performance over a large range of geometries. A good agreement was found between the simulated and measured optical behavior of such AR arrays with a normal reflectance within the visible range of approximately 4 % for the use of a glass substrate. The photocurrent of AR-coated a-Si:H solar cells was found to be 2 % higher than the reference value of an uncoated cell whereas, for AR-coated tandem thin film Si cells, the increase was 3 % for the top a-Si:H cell and 2 % for the bottom microcrystalline Si cell. [ABSTRACT FROM AUTHOR]

ABSTRACT Nanocomposites based on 10 to 60 vol % cellulose nanofibers (NFC) in a photopolymerizable hyperbranched acrylate matrix were prepared. Unmodified NFC and NFC chemically modified with a silane coupling agent and with ceric ammonium nitrate for direct polymer grafting from the cellulose surface were used. A homogeneous dispersion of NFC in the matrix was obtained in each case, leading to a marked improvement in oxygen barrier (up to nine times) and thermomechanical properties (storage modulus increased up to seven times). The mechanisms involved in the permeability reduction were investigated, revealing non-monotonic trends in the evolution of the solubility and diffusion coefficients with NFC content. Most significantly, the inherent moisture sensitivity of the oxygen permeability of the NFC was found to be drastically reduced when it was dispersed in the polymer matrix, particularly after chemical modification, underlining the promise of the present approach for the production of robust, high barrier organic films. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40604. [ABSTRACT FROM AUTHOR]

Venous thrombosis ( VT) is one of the leading causes of maternal death in the western world, but the genetic causes of pregnancy-related VT are insufficiently understood. The aim of this study was to investigate the association between common genetic variations in candidate genes and pregnancy-related VT. We undertook a hospital based case-control study of women with VT during pregnancy or puerperium; controls were women giving birth without having VT. Single nucleotide polymorphisms ( SNPs) were selected in 49 pre-specified candidate genes involved in coagulation, inflammation, and hormonal metabolism in 313 cases and 353 controls. We found new associations between SNPs and total pregnancy-related VT in the genes encoding coagulation factors V and VIII, and p-selectin. Additional new associations between SNPs and antenatal VT were found in the genes encoding the epidermal growth factor receptor, the pregnane X receptor, and protein S. Of 21 SNPs previously associated with thrombotic disease, rs2289252 in F11 and rs3917643 in F3 were associated with pregnancy-related VT, while rs4524 in F5 was associated with antenatal VT. [ABSTRACT FROM AUTHOR]

In order to gain new insight into failure mechanisms in poly-L-lactide (PLLA) and PLLA + hydroxyapatite nanocomposites, transmission electron microscopy has been used to investigate room temperature microdeformation in electron transparent thin films of these materials subjected to various heat treatments and deformed in tension using the 'copper grid' technique. In amorphous PLLA the dominant microdeformation mechanism was crazing. Localized fibrillar deformation zones (DZs) were also observed in semicrystalline films, tending to propagate in regions where the lamellar trajectories were at high angles to the tensile axis. Thus, in spherulitic films, in which the lamellae formed well-defined stacks with approximately straight trajectories at the scale of the spherulite radii, individual DZs were observed to propagate over relatively large distances, as in the amorphous films. On the other hand, films cold crystallized by heating from the glassy state showed more homogeneous lamellar textures. These were associated with a relatively high density of low aspect ratio DZs. Addition of well dispersed nanosized hydroxyapatite (nHA) to the amorphous PLLA films was also found to result in an increase in the craze density, attributed to stress concentrations associated with void formation at the PLLA-particle interfaces during deformation. However, interpretation was less straightforward in cold crystallized PLLA + nHA thin films, owing to a correlation between the lamellar texture and the nHA particles. In this case, both void formation and favorable lamellar orientations may have contributed to initiation of the DZs in the vicinity of the particles. The results are argued to be broadly consistent with previous observations of the behavior of bulk PLLA and PLLA + nHA films with a range of microstructures, in which there was evidence for an improvement in ductility in the presence of the nHA, again attributed to voiding at the PLLA-particle interfaces. [ABSTRACT FROM AUTHOR]

Abdominal aortic aneurysm (AAA) is a common condition with high mortality when ruptured. Most clinicians agree that small AAAs are best managed by ultrasonographic surveillance. However, it has been stated in recent reviews that a serum/plasma biomarker that predicts AAA rupture risk would be a powerful tool in stratifying patients with small AAA. Identification of such circulating biomarkers has been to date unsuccessful. In this study, we used a proteomic approach to find new, potential plasma AAA biomarker candidates. Prefractionated plasma samples were analyzed by two-dimensional differential in-gel electrophoresis to identify differentially expressed proteins between four patients with small AAA and four controls without aneurysm. Protein spots that differed significantly between patients and controls were selected and identified by mass spectrometry. Three protein spots had significantly different expression between patients and controls. The most interesting finding was that patients with small AAA had increased levels of the enzyme glycosylphosphatidylinositol-specific phospholipase D (GPI-PLD) compared with the controls without aneurysm. In conclusion, by using a proteomic approach, this pilot-study provides evidence of GPI-PLD as a novel potential plasma biomarker for AAA. Clin Trans Sci 2012; Volume 5: 56-59 [ABSTRACT FROM AUTHOR]

Plasticization of medical grade poly--lactide (PLLA) by addition of polyethylene glycol (PEG) with various molar masses has been evaluated as means of producing low stiffness matrices for bioresorbable scaffolds for soft-tissue engineering applications. As reported previously, the T of injection molded specimens of the PLLA/PEG blends decreased strongly with PEG content, so that at PEG contents of 15 and 25 wt % it became significantly lower than normal human body temperature, implying an essentially rubber-like mechanical response in vivo. The degree of crystallinity of the moldings also increased strongly with PEG content, reaching a maximum of about 60 wt % at 25 wt % PEG. Moreover, after the immersion in phosphate-buffered saline for 5 days in 37°C to simulate conditions in vivo, the moldings with the highest PEG contents showed increased water uptake and, for relatively low molar mass PEG, significant mass loss, associated with phase separation and leaching of the PEG. Blends with relatively low PEG contents also showed large increases in their degree of crystallinity. The implications of these changes for the in vivo performance of the blends and their potential for development as matrices for bioresorbable scaffolds are discussed in the light of results from a series of PLLA/PEG copolymers. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]