Loss Of Purity Research Articles

3D Human iPSC Blood Vessel Organoids as a Source of Flow-Adaptive Vascular Cells for Creating a Human-Relevant 3D-Scaffold Based Macrovessel Model.

3D-scaffold based in vitro human tissue models accelerate disease studies and screening of pharmaceutics while improving the clinical translation of findings. Here is reported the use of human induced pluripotent stem cell (hiPSC)-derived vascular organoid cells as a new cell source for the creation of an electrospun polycaprolactone-bisurea (PCL-BU) 3D-scaffold-based, perfused human macrovessel model. A separation protocol is developed to obtain monocultures of organoid-derived endothelial cells (ODECs) and mural cells (ODMCs) from hiPSC vascular organoids. Shear stress responses of ODECs versus HUVECs and barrier function (by trans endothelial electrical resistance) are measured. PCL-BU scaffolds are seeded with ODECs and ODMCs, and tissue organization and flow adaptation are evaluated in a perfused bioreactor system. ODECs and ODMCs harvested from vascular organoids can be cryopreserved and expanded without loss of cell purity and proliferative capacity. ODECs are shear stress responsive and establish a functional barrier that self-restores after the thrombin challenge. Static bioreactor culture of ODECs/ODMCs seeded scaffolds results in a biomimetic vascular bi-layer hierarchy, which is preserved under laminar flow similar to scaffolds seeded with primary vascular cells. HiPSC-derived vascular organoids can be used as a source of functional, flow-adaptive vascular cells for the creation of 3D-scaffold based human macrovascular models.

Flexible cryogenic air separation unit—An application for low-carbon fossil-fuel plants

The rapid integration of intermittent renewable sources into the electricity grid is driving the need for a flexible cryogenic air separation unit (ASU) coupled with a low-carbon fossil-fuel plant. However, the state-of-the-art ASU process is highly integrated and nonlinear, which can significantly restrict its ramping rate. In this work, we study the fundamental dynamics of a state-of-the-art double-column ASU, focusing on the dynamic characteristics of the highly integrated and nonlinear heat and mass transfers, and we propose basic control methods for achieving high process ramping rates. We found that the vapor–liquid countercurrent flows in the low-pressure column are critical to the cryogenic rectification of air, which governs the ramp rate of the ASU. This countercurrent flow structure is created through a complex heat integration process in the ASU. Here, this process is simplified as a countercurrent heat transfer to reduce the complexity of studying the ASU dynamics. To preserve this flow structure, the heat integration is maintained so that its heat duty follows the ASU load, using several basic controllers on the critical stream flowrates. A flow-driven dynamic ASU model is built in Aspen Plus Dynamics to capture the basic ramping dynamics. This model revealed a fundamental mismatch in the dynamics in the ASU column that causes a significant loss of O2 product purity when ramping down the ASU and slightly increases the purity when ramping up. Based on these findings, we propose a basic control method for rapidly ramping down/up the ASU while maintaining O2 product purity. Simulation results show the ASU basic dynamic process successfully ramps at a rate up to 10 %/min (40–100 % load) while maintaining the O2 product purity at 95.2–95.6 mol%.

Development of Pure Green Thermally Activated Delayed Fluorescence Material by Cyano Substitution.

Multiple resonance (MR)-effect-induced thermally activated delayed fluorescence (TADF) materials have garnered significant attention because they can achieve both high color purity and high external quantum efficiency (EQE). However, the reported green-emitting MR-TADF materials exhibit broader emission compared to those of blue-emitting ones and suffer from severe efficiency roll-off due to insufficient rate constants of reverse intersystem crossing process (kRISC ). Herein, a pure green MR-TADF material (ν-DABNA-CN-Me) with high kRISC of 105 s-1 is reported. The key to success is introduction of cyano groups into a blue-emitting MR-TADF material (ν-DABNA), which causes remarkable bathochromic shift without a loss of color purity. The organic light-emitting diode employing it as an emitter exhibits green emission at 504nm with a small full-width at half-maximum of 23nm, corresponding to Commission Internationale d'Éclairage coordinates of (0.13, 0.65). The device achieves a high maximum EQE of 31.9% and successfully suppresses the efficiency roll-off at a high luminance.

Synthesis, Stereochemical Analysis, and Transformation of Oxa-[7]orthocyclophene

Abstract Planar chiral oxa-[7]orthocyclophene 1a was designed and synthesized with two different synthetic routes. X-ray crystallographic analyses of 1a and its platinum complex revealed a highly distorted ring structure and the absolute stereochemistry of 1a, respectively. Epoxidation and [2,3]-Wittig rearrangement of 1a provided with central chiral molecules, without the loss of enantiomeric purity.

Enantioselective Friedel-Crafts Alkylation Reaction of Pyrroles with N-Unprotected Alkynyl Trifluoromethyl Ketimines.

Developed herein is an enantioselective Friedel-Crafts alkylation reaction of N-unprotected alkynyl trifluoromethyl ketimines with pyrroles catalyzed by chiral phosphoric acid to furnish chiral primary α-trifluoromethyl-α-(2-pyrrolyl)propargylamines with high enantioselectivity. Transformation of the alkynyl group of the adducts afforded optically active α-trifluoromethylated amines bearing various substituents such as alkyl, alkenyl, enyne, and triazole without loss of optical purity.

Türk Sinemasinda Toplumsal Gerçekçi Filmlerde İstanbul Temsili: Acı Hayat ve Banker Bilo Filmleri Örneği

In this study, it has been tried to explain how and with which variables Istanbul is represented in the films within the scope of the social realist cinema movement in Turkey by analyzing the selected sample films. In this context, in the study, first of all, the social realism movement in Turkish cinema was mentioned and the films shot in line with this movement were briefly mentioned. In the study, the representations of Istanbul in Yeşilçam films were mentioned and the films selected as samples were examined by text analysis method. Sample films are films that are evaluated within the scope of the social realism movement in Turkish cinema and shot in different periods. These films are Acı Hayat made in 1962 and Banker Bilo made in 1980. As a result of the study, it has been that in both films, Istanbul is represented as a trap that alienates people from themselves and society, pushes them to loneliness and mistakes, and leads to the loss of purity and goodness. Keywords: Turkish Cinema, Social Realism, Istanbul, City, Cinema

Asymmetric Construction of All‐Carbon Quaternary Stereocenters via Organocatalytic α‐Hydroxymethylation of Malonic Diesters Using Aqueous Formaldehyde

AbstractAn organocatalyzed α‐hydroxymethylation of α‐monoalkyl malonic diesters using 37% aqueous formaldehyde (formalin) as a one‐carbon electrophilic unit to generate all‐carbon substituted quaternary stereocenters has been developed. In the course of our exploration of catalytic methodologies, a metal‐free cooperative catalytic approach with cinchonidine and squaramide co‐catalysts was found to improve both reactivity and enantioselectivity in this transformation. Our organocatalytic method represents the first example of an enantioselective α‐hydroxymethylation of a malonic diester. The enantioenriched α‐hydroxymethyl products could be recrystallized with high recovery, yielding optically pure materials. Moreover, to demonstrate the utility of this methodology, the all‐carbon substituted α‐quaternary stereogenic malonate was converted to both (S)‐ and (R)‐4,4‐disubstituted oxazolidin‐2‐ones without loss of optical purity.

Helicity Modulation in NIR‐Absorbing Porphyrin‐Ryleneimides

AbstractPeripheral substitution of a π‐extended porphyrin with bulky groups produces a curved chromophore with four helical stereogenic units. The curvature and stereochemistry of such porphyrins can be controlled by varying the substituents, coordinated metal ions, and apical ligands. In particular, when the achiral saddle‐shaped free bases are treated with large metal ions, i.e., CdII or HgII, the resulting complexes convert to chiral propeller‐like configurations. X‐ray diffraction analyses show that apical coordination of a water molecule is sufficient to induce a notable bowl‐like distortion of the cadmium complex, which however retains its chiral structure. For phenyl‐ and tolyl‐substituted derivatives, the conversion is thermodynamically controlled, whereas complexes bearing bulky 4‐(tert‐butyl)phenyl groups transform into their chiral forms upon heating. In the latter case, the chiral Hg porphyrin was converted into the corresponding free base and other metal complexes without any loss of configurational purity, ultimately providing access to stable, enantiopure porphyrin propellers.

Helicity Modulation in NIR-Absorbing Porphyrin-Ryleneimides.

Peripheral substitution of a π‐extended porphyrin with bulky groups produces a curved chromophore with four helical stereogenic units. The curvature and stereochemistry of such porphyrins can be controlled by varying the substituents, coordinated metal ions, and apical ligands. In particular, when the achiral saddle‐shaped free bases are treated with large metal ions, i.e., CdII or HgII, the resulting complexes convert to chiral propeller‐like configurations. X‐ray diffraction analyses show that apical coordination of a water molecule is sufficient to induce a notable bowl‐like distortion of the cadmium complex, which however retains its chiral structure. For phenyl‐ and tolyl‐substituted derivatives, the conversion is thermodynamically controlled, whereas complexes bearing bulky 4‐(tert‐butyl)phenyl groups transform into their chiral forms upon heating. In the latter case, the chiral Hg porphyrin was converted into the corresponding free base and other metal complexes without any loss of configurational purity, ultimately providing access to stable, enantiopure porphyrin propellers.

Effect of temperature, current density and mass transport during the electrolytic removal of magnesium ions from lithium rich brines

Full depletion of magnesium cations from lithium rich brines is vital for the successful crystallization of battery grade lithium salts in subsequent production steps. In a three compartment water electrolyser, we demonstrate the full abatement of Mg2+, with concomitant recovery of magnesium hydroxide. We have studied the influence of three operational variables, current density, temperature and forced mass transport in the coulombic efficiency, cell voltage between the electrodes, solid purity and lithium ions loss. Response surface methodology was used to model the system. Our results show that both in terms of energy efficiency, product purity and minimal Li+ loss it is best to work at very low current density, high flow rate, and high temperature (32 A m−2, 60 °C, and 18 L h−1). Working at higher current density, low temperature, and high flow rate (100 A m−2, 26.5 °C, and 18 L h−1) still guarantees a product of acceptable quality while keeping a moderate electrical consumption. The current density is the factor that affects results the most. High current densities are correlated with a faster nucleation, and smaller particle size, resulting in higher adsorption from other ions and co-precipitation of CaB by-products.

A scalable, integrated downstream process for production of a recombinant measles virus-vectored vaccine

Purification of very large and complex, enveloped viruses, such as measles virus is very challenging, it must be performed in a closed system because the final product cannot be sterile filtered and often loss of virus titer and poor product purity has been observed. We developed a purification process where the clarified and endonuclease treated culture supernatant is loaded on a restricted access chromatography medium where small impurities are bound and the virus is collected in the flow-through, which is then concentrated, and buffer exchanged by ultra/diafiltration. Up to 98.5% of host cell proteins could be captured by direct loading of clarified and endonuclease treated cell culture supernatant. Reproducible process performance and scalability of the chromatography step were demonstrated from small to pilot scale, including loading volumes from 50 mL up to 9 L. A 10-fold virus concentration was achieved by the ultrafiltration using a 100 kDa flat-sheet membrane. The order of individual process steps had a large impact on the virus infectivity and total process yields. The developed process maintained virus infectivity and is twice as fast as the traditional process train, where concentration is performed before loading on the chromatography column. Capturing impurities by the restricted access medium makes it a platform purification process with a high flexibility, which can be easily and quickly adapted to other vectors based on the measles virus vector platform.

Glassy quantum dynamics of disordered Ising spins

We study the out-of-equilibrium dynamics of the quantum Ising model with power-law interactions and positional disorder. For arbitrary dimension $d$ and interaction range $\ensuremath{\alpha}\ensuremath{\ge}d$ we analytically find a stretched-exponential decay of the global magnetization and ensemble-averaged single-spin purity with a stretch power $\ensuremath{\beta}=d/\ensuremath{\alpha}$ in the thermodynamic limit. Numerically, we confirm that glassy behavior persists for finite system sizes and sufficiently strong disorder. We identify dephasing between disordered coherent pairs as the main mechanism leading to a relaxation of global magnetization, whereas genuine many-body interactions lead to a loss of single-spin purity which signifies the buildup of entanglement. The emergence of glassy dynamics in the quantum Ising model extends prior findings in classical and open quantum systems, where the stretched-exponential law is explained by a scale-invariant distribution of timescales, to both integrable and nonintegrable quantum systems.

Preparation of high purity Sm3+-doped Ga-Ge-As-Se glass and low-loss fiber

The high-purity 700 ppmw Sm3+-doped Ga2.2Ge26.5As14.6Se56.7 glass is prepared and investigated. The glass has an extra-low content of impurities, a wide transmission range (0.9–16 μm), a high glass transition temperature (330 °C), and high stability against crystallization. The low content of limiting impurities is the result of the multistage procedure for the purification of individual components, the basic glass-forming melt, as well as the chemical transport reactions technique. The Sm3+-doped Ga-Ge-As-Se glass shows photoluminescence in the spectral regions 1.2–1.3 μm, 1.4–1.6 μm, 1.75–2 μm, 2.2–3 μm, and 3.5–4.2 μm. In a complex system of samarium levels, the longest-lived energy transition is established to be the one at 3.7 μm with a lifetime of 60 μs From the high-purity Sm3+-doped Ga-Ge-As-Se glass, the single-index fiber with minimum optical loss of 0.5 dB/m at 5.7 μm and without impurity bands in spectrum is fabricated. It is the best result concerning the glass purity and optical loss among Sm3+-doped chalcogenide glass fibers.

Population genetic structure of European wildcats inhabiting the area between the Dinaric Alps and the Scardo-Pindic mountains

Habitat fragmentation and loss have contributed significantly to the demographic decline of European wildcat populations and hybridization with domestic cats poses a threat to the loss of genetic purity of the species. In this study we used microsatellite markers to analyse genetic variation and structure of the wildcat populations from the area between the Dinaric Alps and the Scardo-Pindic mountains in Slovenia, Croatia, Serbia and North Macedonia. We also investigated hybridisation between populations of wildcats and domestic cats in the area. One hundred and thirteen samples from free-leaving European wildcats and thirty-two samples from domestic cats were analysed. Allelic richness across populations ranged from 3.61 to 3.98. The observed Ho values ranged between 0.57 and 0.71. The global FST value for the four populations was 0.080 (95% CI 0.056–0.109) and differed significantly from zero (P < 0.001). The highest FST value was observed between the populations North Macedonia and Slovenia and the lowest between Slovenia and Croatia. We also found a signal for the existence of isolation by distance between populations. Our results showed that wildcats are divided in two genetic clusters largely consistent with a geographic division into a genetically diverse northern group (Slovenia, Croatia) and genetically eroded south-eastern group (Serbia, N. Macedonia). Hybridisation rate between wildcats and domestic cats varied between 13% and 52% across the regions.

Development of chiral bisphosphoric acid/boronic acid co-catalyst system for enantioselective SN2’ reaction

An enantioselective intramolecular SN2’ reaction of geometrically defined allylic substrates was developed by introducing a co-catalyst system composed of chiral bisphosphoric acid and phenylboronic acid. In the enantioselective nucleophilic substitution reaction using chiral phosphoric acids and derivatives (CPAs) as the catalyst, the formation of the corresponding CPA ester, which is afforded through the SN2 reaction of the substrate with the nucleophilic phosphate anion generated during the activation of a leaving group, has been a serious problem because of the catalyst deactivation. The developed co-catalyst system surmounted this fundamental problem by efficiently suppressing the catalyst deactivation process to afford enantioenriched vinyl epoxides in good yields with moderate to high enantioselectivities. Mechanistic elucidation of the present enantioselective intramolecular SN2’ reaction using the co-catalyst system revealed that the leaving group is involved in the enantio-determining transition states, and the anti-SN2’ pathway is considered to be the rational mechanism of the present allylic substitution reaction. In addition, the stereospecific Meinwald rearrangement of the thus-formed enantioenriched vinyl epoxide was aided by an equimolar amount of a Lewis acid, affording the corresponding all-carbon quaternary α-vinyl cyclohexanone without marked loss of enantiomeric purity.

Circular anti-resonance fibre supporting orbital angular momentum modes with flat dispersion, high purity and low confinement loss

A novel ring anti-resonance fibre (ARF) is designed and demonstrated for the transmission of orbital angular momentum (OAM) modes. The fibre consists of two layers of negative curvature tubes arranged orderly inside and outside the ring region and OAM modes can be transmitted in the ring region. The properties of the fibre are investigated by the finite element method based on the COMSOL multiphysics software and a manufacturing method is proposed. The fibre shows stable transmission of 30 OAMs in the 1.5–1.6 μm band, low and flat dispersion (5.98 ps/(km nm)), extremely small nonlinear coefficient (0.539 km−1 W−1 at 1.55 μm) and confinement loss (10−9–10−11 dB/m), as well as high OAM purity (larger than 98.295%). Therefore, the structure has immense potential in optical communication.

Sub-quantum Fisher information

The quantum Fisher information (QFI) plays a crucial role in quantum information theory and in many practical applications such as quantum metrology. However, computing the QFI is generally a computationally demanding task. In this work we analyze a lower bound on the QFI which we call the sub-quantum Fisher information (sub-QFI). The bound can be efficiently estimated on a quantum computer for an n-qubit state using 2n qubits. The sub-QFI is based on the super-fidelity, an upper bound on Uhlmann’s fidelity. We analyze the sub-QFI in the context of unitary families, where we derive several crucial properties including its geometrical interpretation. In particular, we prove that the QFI and the sub-QFI are maximized for the same optimal state, which implies that the sub-QFI is faithful to the QFI in the sense that both quantities share the same global extrema. Based on this faithfulness, the sub-QFI acts as an efficiently computable surrogate for the QFI for quantum sensing and quantum metrology applications. Finally, we provide additional meaning to the sub-QFI as a measure of coherence, asymmetry, and purity loss.

A novel twin-column continuous chromatography approach for separation and enrichment of monoclonal antibody charge variants.

Downstream processing of mAb charge variants is difficult owing to their similar molecular structures and surface charge properties. This study aimed to apply a novel twin‐column continuous chromatography (called N‐rich mode) to separate and enrich acidic variants of an IgG1 mAb. Besides, a comparison study with traditional scaled‐up batch‐mode cation exchange (CEX) chromatography was conducted. For the N‐rich process, two 3.93 mL columns were used, and the buffer system, flow rate and elution gradient slope were optimized. The results showed that 1.33 mg acidic variants with nearly 100% purity could be attained after a 22‐cycle accumulation. The yield was 86.21% with the productivity of 7.82 mg/L/h. On the other hand, for the batch CEX process, 4.15 mL column was first used to optimize the separation conditions, and then a scaled‐up column of 88.20 mL was used to separate 1.19 mg acidic variants with the purity of nearly 100%. The yield was 59.18% with the productivity of 7.78 mg/L/h. By comparing between the N‐rich and scaled‐up CEX processes, the results indicated that the N‐rich method displays a remarkable advantage on the product yield, i.e. 1.46‐fold increment without the loss of productivity and purity. Generally, twin‐column N‐rich continuous chromatography displays a high potential to enrich minor compounds with a higher yield, more flexibility and lower resin cost.

COMMUNICATIVE AND PAGMATIC FEATURES OF COLLOQUIAL VOCABULARY IN NEWSPAPER STYLE

The article describes issues on the communicative and pragmatic features of colloquial words in newspaper style. At present, the main source of updating the literary norm is the mass media, including periodicals. It actively responds to the events of each day and thereby reflects changes in the vocabulary of the language. As we know, the newspaper style is currently characterized by a irony, emotional intensity and expressiveness, which makes the language of journalism mobile, subtly responsive to situations in society. At the same time, the opposite phenomena are also observed - the loss of literary purity and a general decline in the style of the mass press. Consequently, while selecting lexical means, a journalist must remember that he/she is responsible for the future of the language, for developing the language taste of readers.

Adaptive MPC Controller based Cascade Control of Distillation Column Parameters Estimation and Optimization

One of the key element of many industrial process plants is a crude oil distillation system. This system requires heat for the vaporization of a mixture of feed to the distillation column in vapor form. In the existing process of distillation, an abnormal change of heat is exhibited due to improper control and monitoring of disturbances affecting the plant. This would result for undesired loss of product and product purity to be reduced. The parameters that are expected to be considered in the analysis, model and control of a distillation system described under the proposed study are inlet feed temperature, distillation column temperature, feed composition, internal liquid and vapor composition, feed flow rate, reboiler temperature and an external reflux temperature to the distillation tower. Controlling distillation column parameters with Adaptive model predictive control allows for the determination of the predicted future instant values of the plant outputs. Using such control technique, the controlled plant outputs such as the temperature of distillation column, feed preheater, re boiler and the upper reflux is properly controlled and their parameters are estimated using recursive least squares approach in the entire process adaptation mechanism. From the analysis and optimization work made on the proposed system, the efficiency of the plant outputs in tracking their corresponding set point has improved based on the value of the transient system parameters as well as the value of relative volatility of feed mixture to the column. As per the finding in the analysis of the process, 95.4% and 93.5% improvement on the set point tracking and to amount of evaporation liquid feed has been obtained respectively. On the other hand an improvement on transient parameters has been achieved to all plant outputs. As per the result obtained from the analysis, the peak overshoot, settling time and peak time of the system response has found to be less than 40% including the effect of measured disturbance to the plant. Hence, entire process variable optimization has been performed using the parameters of the model predictive controller to provide the proper degree of stability. Finally the proposed method of study has compared with with other control strategies through which the performance the proposed design has been ensured.