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Recycling multilayer plastic packaging is challenging due to its intrinsic compositional heterogeneity. A promising route to increase recycling rates for these materials is delamination, which allows recycling the polymers separately. Yet, this process is not well understood on a fundamental level. This study aimed to obtain first principles‐based insights of the delamination mechanism of multilayer flexible packaging film (MFPF) with carboxylic acids. Delamination of MFPFs was described through a model based on Fick's first law of diffusion and first‐order dissolution kinetics of polyurethane adhesives. The model was experimentally tested on 5 different MFPFs at different temperatures (50–75 °C), formic acid concentrations (50–100 vol %), and solid/liquid (S/L) ratios (0.005, 0.025, and 0.12 g mL−1). Under the studied conditions the model proved to successfully estimate the delamination time of MFPF with the average Theil's Inequality Coefficient (TIC) value of 0.14. Essential for scaling‐up delamination processes is the possibility to use high S/L ratios as the solubility of the adhesive is rarely limiting., Multilayer plastic packaging: Delamination of multilayer flexible packaging films (MFPFs) is described through a model based on Fick's first law of diffusion and first‐order dissolution kinetics of polyurethane adhesives. The model is validated on typical MFPFs under different experimental conditions. Under the studied conditions the model successfully estimates the delamination time of MFPFs.

The progressive neuropathological damage seen in Parkinson's disease (PD) is thought to be related to the spreading of aggregated forms of α‐synuclein. Clearance of extracellular α‐synuclein released by degenerating neurons may be therefore a key mechanism to control the concentration of α‐synuclein in the extracellular space. Several molecular chaperones control misfolded protein accumulation in the extracellular compartment. Among these, clusterin, a glycoprotein associated with Alzheimer's disease, binds α‐synuclein aggregated species and is present in Lewy bodies, intraneuronal aggregates mainly composed by fibrillary α‐synuclein. In this study, using murine primary astrocytes with clusterin genetic deletion, human‐induced pluripotent stem cell (iPSC)‐derived astrocytes with clusterin silencing and two animal models relevant for PD we explore how clusterin affects the clearance of α‐synuclein aggregates by astrocytes. Our findings showed that astrocytes take up α‐synuclein preformed fibrils (pffs) through dynamin‐dependent endocytosis and that clusterin levels are modulated in the culture media of cells upon α‐synuclein pffs exposure. Specifically, we found that clusterin interacts with α‐synuclein pffs in the extracellular compartment and the clusterin/α‐synuclein complex can be internalized by astrocytes. Mechanistically, using clusterin knock‐out primary astrocytes and clusterin knock‐down hiPSC‐derived astrocytes we observed that clusterin limits the uptake of α‐synuclein pffs by cells. Interestingly, we detected increased levels of clusterin in the adeno‐associated virus‐ and the α‐synuclein pffs‐ injected mouse model, suggesting a crucial role of this chaperone in the pathogenesis of PD. Overall, our observations indicate that clusterin can limit the uptake of extracellular α‐synuclein aggregates by astrocytes and, hence, contribute to the spreading of Parkinson pathology., Main Points Extracellular clusterin binds α‐synuclein fibrils thus limiting their uptake by murine and human astrocytes.Reduced levels of clusterin improve α‐synuclein aggregates clearance by astrocytes.

The flagship member of the antiplasmodial isocyanoterpenes, 7,20-diisocyanoadociane (DICA), was synthesized from dehydrocryptone in 10 steps, and in 13 steps from commercially available material. Our previous formal synthesis was reengineered, leveraging only productive transformations to deliver DICA in fewer than half the number of steps of our original effort. Important contributions, in addition to the particularly concise strategy, include a solution to the problem of axial nucleophilic methylation of a late-stage cyclohexanone, and the first selective synthesis and antiplasmodial evaluation of the DICA stereoisomer with both isonitriles equatorial.

The initial stability of cementless total hip arthroplasty (THA) implants is obtained by an interference fit that allows osseointegration for a long term secondary stability of the implant. Yet, finding the insertion endpoint that corresponds to an appropriate initial stability is currently often based on a number of subjective experiences of the orthopedic surgeon, which can be challenging. In order to assist the orthopedic surgeons in their pursuit to find this optimal initial stability, this study aims to determine whether the analysis of sound that results from the implant insertion hammer blows can be used to objectively monitor the insertion process of cementless THA implants. An in vivo study was conducted. The experimental results revealed vibro-acoustic behavior sensitive to implant seating, related to the low frequency content of the response spectra. This sensitive low-frequency behavior was quantified by a set of specific vibro-acoustic features and metrics that reflected the power and similarity of the low-frequency response. These features and metrics allowed monitoring the implant seating and their convergence agreed well with the endpoint of insertion as determined by the orthopedic surgeon. Intraoperative fractures caused an abrupt and opposite change of the vibro-acoustic behavior prior to the notification of the fracture by the orthopedic surgeon. The observation of such an abrupt change in the vibro-acoustic behavior can be an important early warning for loss of implant stability. The presented vibro-acoustic measurement method shows potential to serve as a decision supporting source of information as it showed to reflect the implant seating. ispartof: JOURNAL OF ORTHOPAEDIC RESEARCH vol:39 issue:6 pages:1164-1173 ispartof: location:United States status: published

Although the fanciful notion that the Black Death bypassed the Low Countries has long been rejected, nevertheless a persistent view remains that the Low Countries experienced only a ‘light touch’ of the plague when placed in a broader European perspective, and recovered quickly and fully. However, in this article an array of dispersed sources for the Southern Netherlands together with a new mortmain accounts database for Hainaut show that the Black Death was severe, perhaps no less severe than other parts of western Europe; that serious plagues continued throughout the fourteenth and fifteenth centuries; and that the Black Death and recurring plagues spread over vast territories—including the countryside. The previous conception of a ‘light touch’ of plague in the Low Countries was created by the overprivileging of particular urban sources, and a failure to account for the rapid replenishment of cities via inward migration, which obscured demographic decimation. We suggest that the population of the Low Countries may not have recovered faster than other parts of western Europe but instead experienced a greater degree of post‐plague rural–urban migration.

In this study, the influence of the shape of the doctor blade on the flow inside the tape casting unit and on the resulting tape properties is investigated both numerically and experimentally. Using the results from the analysis of the produced tape and from the simulations of the flow inside the tape casting unit, the relationships between blade geometry and the particle orientation in the resulting tape, as well as the resulting tape thickness, are shown. Additionally, the experimentally and numerically obtained results were compared to an analytical model for the prediction of the tape thickness. The simulations were carried out using the particle-based smoothed particle hydrodynamics method using a non-Newtonian fluid model to describe the ceramic slurry. Both in experiment and simulation, the influence of the blade geometry on the resulting tape shows good agreement.

Older consumers are often neglected as a target group because they are considered brand loyal and not flexible in their consumption habits. However, previous research suggests that life transitions may be associated with changes in consumers’ behavior. To investigate whether late-life transitions are associated with a greater likelihood of changing the regularly bought yogurt brand, we analyzed real purchase data of German consumers from 2004 to 2008. Our findings provide empirical evidence that changes in social relationships (change in household size, relocation) are associated with a higher likelihood of changes in first yogurt brand and first grocery chain for older consumers. These findings have implications for policy makers and marketing practitioners. Les consommateurs plus âges sont souvent negliges comme groupe-cible, car ils sont consideres comme etant fideles a leurs marques et peu flexibles dans leurs habitudes de consommation. Cependant, des recherches anterieures suggerent que les transitions de la vie peuvent etre associees a des changements d'habitudes de consommation alimentaire. Afin de determiner si les transitions qui se passent en fin de vie sont associes avec une plus grande probabilite de changer la marque de yoghourt achetee regulierement, nous analysons les donnees d'achats reels des consommateurs allemands de 2004 a 2008. Nos resultats fournissent des preuves empiriques sur la probabilite de changements de (a) la marque premiere de yoghourt et la chaine de supermarche premiere pour les consommateurs les plus âges a la suite des changements dans les relations sociales comme le changement de la taille de menage et le demenagement. Et en plus ces resultats ont des repercutions pour les decideurs et les professionnels du marketing.

In this study, laminates consisting of sintered alumina substrates and green Low Temperature Co-fired Ceramics (LTCC) tapes have been produced via Cold Low Pressure Lamination which is based on adhesive tapes for joining of layers at room temperature and pressures

Dimensional control is one of the basic problems in ceramic processing, especially for tape cast ceramic sheets which are used to build up multilayer structures for high-integrated components. Uncontrolled anisotropic shrinkage can cause geometrical distortion and circuit failure of multilayer ceramics during sintering. The understanding of the relationship between green tape microstructure and shrinkage anisotropy is of great importance for further miniaturization of multilayer devices. In this study, alumina powders with spherical particle shape were used to cast green tapes. The microstructure as well as the pore orientation and the shrinkage behavior were analyzed. According to the sintering theory, grain growth and pore elimination are the two most important mechanisms to describe sintering shrinkage. In this work, three-dimensional shrinkage behavior of tape cast alumina powders with spherical particle shape was investigated and correlated with pore orientation in the microstructure. Specifically, the reason for the different shrinkage in z-direction compared to the lateral shrinkage is in focus. The study is based on experiments as well as on mathematical visualization.

During sintering of tape cast products, anisotropic shrinkage occurs, which can be attributed to an anisotropic green tape structure concerning particle and pore orientation. Little is known about the shrinkage during binder burnout (BBO) and its relation to the microstructure of green tapes including the binder–plasticizer phase. Therefore, the article determines the shrinkage behavior of green tapes derived from alumina powders with different particle shape during binder burnout and prefiring in all spatial directions. The shrinkage after prefiring relative to the green and the debindered states is also discussed. The interrelation between shrinkage behavior and microstructure is investigated in dependence on different process parameters and specifically on the thermal behavior of the binder–plasticizer phase in the green tapes. It is shown that the subtraction of the BBO shrinkage from the total shrinkage results in completely different data for the sintering shrinkage anisotropy in z direction.

Eine Moglichkeit zur Integration fluktuierender Energieerzeugung in das Energiesystem stellt die Verwendung von elektrolytisch erzeugtem Wasserstoff zur Herstellung von Methan, Ammoniak oder Methanol dar. Hier wird ein flexibles Prozesskonzept zur Herstellung von Ammoniak vorgestellt und auf technischer und okonomischer Ebene mit den Power-to-Gas-Konzepten verglichen. Insbesondere der im Vergleich hohe Marktpreis von Ammoniak generiert Vorteile gegenuber der Produktion von Erdgassubstituten und fuhrt zu einer hoheren Anlagenlaufzeit mit operativen Erlosen. Producing hydrogen-rich chemicals, such as methane, ammonia or methanol, from renewable energy may foster the integration of renewables into the current energy system. Here, a flexible ammonia synthesis concept is introduced, which is then compared to the widely discussed power-to-gas concepts on a technical and economic level. The current ammonia prices result in comparably high hydrogen-specific revenues, which imply the ability to operate the system more profitable under fluctuating electricity prices and thereby increase the plant capacity factor.

Through evaluation of current literature and survey data, this exploratory study aimed to determine factors that influence enrolment in master's level education and attendant delay of life decisions. A total of 134 master's students at a German university were surveyed. The mean age was 25 years and respondents were nearly equal parts German and non-German nationalities. Results show how cultural factors motivate enrolment in master's programmes and how enrolment influences the timing of other important life decisions. Respondents expected significant benefits to social status, job placement and income. While this small-scale study does not include all decision factors and its findings are not fully generalizable, we hope it motivates further research in this area.

Lead zirconate titanate (PZT) ceramics are used in a wide range of applications as sensors and actuators. Typically, they are formulated by the mixed oxide route, using several mixing and milling steps. Due to wear, these processes introduce impurities into the ceramic mass, which on their part can strongly influence densification behaviour and final properties of the PZT. In this study, the effect of such impurities, such as iron oxide, alumina, and silica, on the sintering behaviour and microstructure development of PZT ceramic is evaluated. A commercial Nb-doped PZT powder was used and doped by adding Al2O3, SiO2, and Fe2O3 with an amount of up to 0.001 mol%. Bulk samples were prepared and sintered in air. The mass loss, density, and grain size were correlated by regression analysis using the doping elements and levels, respectively. Due to the complex interactions between the oxides and the ceramic properties, the experiments were performed with the design-of-experiment method (DoE). The results showed a significant influence of these low amounts of doping levels on the microstructure development. Moreover, it was shown that doping after calcination affects the microstructure in a similar way to doping before calcination. Thus, a possibility to compensate concentration variations in the calcined ceramic mass is demonstrated, to homogenize the chemical composition and the final microstructure of the sintered PZT ceramic in the manufacturing processes.

Background Radiofrequency ablation (RFA) can unfavorably cause coagulum on the ablation electrode. The aim of this study was to assess this phenomenon on three different multielectrode catheters used to treat persistent atrial fibrillation with duty-cycled RFA. Methods and results Twenty-six consecutive patients have been treated with the pulmonary vein ablation catheter (PVAC) and the multiarray ablation catheter (MAAC). In 13 patients, additional ablation with the multiarray septal catheter (MASC) has been performed. The multichannel RF generator GENius™ (Medtronic Inc., Minneapolis, MN, USA) independently delivered energy in a bipolar and unipolar mode (ratio of 4/1, 2/1, or 1/1) to any of the electrodes. Versions 14.2, 14.3, and 14.4 of the generator were used. Coagulum presence was determined postablation by careful visual inspection of the catheter electrodes. No coagulum formation was visualized on the PVACs. Coagulum formation was visualized in 59% of the electrodes of the MAACs using a 2/1 mode and the 14.2 software version versus 69% using the 14.4 version and a 2/1 mode (P = 0.7) versus 14% of the electrodes applying a 1/1 ratio and the 14.4 software version (P < 0.001). Conclusions Duty-cycled RFA in 2/1 bipolar/unipolar ratio generates a substantial frequency of coagulum formation on the multielectrode catheters MAAC and MASC. The use of the 14.4 version of the software to drive the RF generator and the use of energy in the default 1/1 bipolar/unipolar ratio could significantly reduce the frequency of coagulum formation, but so far, could not completely overcome it. The PVAC did not form coagulum, regardless of generator version or energy ratio used.

What's known on the subject? and What does the study add? In a recent rtMRI study, we were able to show that, during initiation of voiding, there was both funnelling of the bladder neck and simultaneous contraction of the ventral prostate. We presumed that the vertical contraction of the ventral prostate contributes to the initiation of successful micturition. The question remained as to whether this shortening of the ventral prostate is predominantly caused by contractile elements in the organ itself, or by surrounding contractile elements of the pelvic floor. In our study we provide insight in to anatomical changes, and biometric and functional analysis of the prostate during micturition. A sagittal contraction of the ventral prostate and the longitudinal smooth muscle elements at the onset of voiding, which can be observed on MRI, is likely to shorten and open up the prostatic urethra. Objective To investigate if in vitro contractile strength of the prostate and the prostatic urethra might correlate with the shortening of the ventral prostate seen on real-time magnetic resonance imaging (rtMRI). Micturition is a complex process that includes anatomical and neurological interactions for successful voiding. Recently we described on rtMRI that vertical contraction of the ventral prostate precedes initiation of male micturition and may contribute to the funnelling of the bladder neck. Patients and Methods In all, 10 patients undergoing radical prostatectomy (RP) were enrolled. Approval was obtained from all patients and by the local Ethics Committee. Preoperative rtMRI during voiding was performed as described before in eight patients undergoing RP, measuring the difference of the cranio-caudal distance of the ventral prostate (VP). To roughly estimate the amount of force required to deform the prostate in a vertical direction as seen on rtMRI, we uniaxially compressed the organ immediately after surgery by the same distance, assuming incompressibility and isotropy of prostatic tissue. A muscle strip (3 × 3 mm) from the ventral prostate, dorsal prostate and prostatic urethra was obtained after pathological evaluation. Contraction was elicited by electrical-field stimulation (EFS: 0.1 ms pulses at 2, 4, 8, 16, 32 and 64 Hz for 4 s). Results There was a mean cranio-caudal contraction of the ventral prostate by 7.6 mm at the onset of micturition on rtMRI (P = 0.002). The mean (sd) contractile force of strips elicited by EFS at 32 Hz was 1472.44 (706.88) mN for the ventral prostate, 1044.24 (894.66) mN for the dorsal prostate, and 639.10 (785.06) mN for the prostatic urethra (P = 0.02). Extrapolating these values to the whole organ diameter, we calculated comparable force as observed in compression experiments. Conclusions Our functional and biometric in vitro analyses of prostate tissue showed sufficient contractile strength of the ventral prostate to induce a shortening of the organ as seen on rtMRI. There was significant higher contractile strength in the ventral prostate than in the dorsal prostate or the proximal urethra. The consistency of in vivo and in vitro results underlines the significance of the ventral prostate for the initiation of normal micturition.