Langekloster8621
The application of a model-based approach for industrial chromatography development requires the capability of the model to describe protein elution under high loading and overloading conditions. B02 mouse In a previous work, an extensive dataset was created to model the elution behavior of a bispecific antibody (bsAb) on the strong cation exchange resin POROS™ XS. Thereby, the pH-dependence of the model parameters in the Steric Mass Action (SMA) model could be examined and described over a pH range of 4.5 to 8.9. However, discrepancies between simulated and experimental data were observed under high loading and overloading conditions, particularly in the lower pH range (pH 4.5 to 5.3) and in the higher pH range (pH 6.0 to 9.0). In this work, these discrepancies are studied by performing new experiments which show that these differences were primarily not caused by limitations of the SMA model. At lower pH values, overloading phenomena such as protein breakthrough during the loading phase, additional peaks, and peak shoulders occurred. The application of various experiments performed with different Na+ concentrations and different loading times during sample loading revealed that intraparticle diffusion effects and conformational changes of the bsAb are responsible for these overloading phenomena at low pH. The applied lumped rate mass transfer model is not adequate and should be extended to consider these effects. At higher pH, the assumption of describing the bsAb's elution behavior with only one simulated species was insufficient to predict complex peak shapes that arise because of multi-component elution of the bsAb's charge variants. The extension of the model to a simple multi-component system consisting of two variants allowed the prediction of a majority of the complex elution profiles.Modified QuEChERS and triple quadrupole mass spectrometry (LC and GC-MS/MS) technology were used to sequentially analyze pesticides, veterinary drugs, and mycotoxins in feed. In order to analyze the harmful substances that may remain or occur in the feed, we performed optimization experiments for sample preparation and LC-MS/MS and GC-MS/MS conditions. Optimized sample preparation involves extracting 5 g of sample with 15 mL of 0.25 M EDTA and 10 mL of acetonitrile. And some extracts were diluted 10-fold with 100 mM ammonium formate aqueous solution and analyzed by LC-MS/MS, and some extracts were purified through 25 mg PSA and analyzed by GC-MS/MS by adding an analyte protectant. We confirmed the matrix effect of feed ingredients and compound feeds, and added a dilution process after extraction to increase on-site efficiency. Matrix-matched calibration was applied for quantification. Method validation was performed for 197 pesticides, 56 components for veterinary drugs, and 5 components for toxins. All the components showed good linearity (r2 ≥ 0.98) in the developed analytical method. For most compounds, the limit of quantitation was 0.05 mg/kg. The recovery rate experiment was repeated three times at three concentrations including LOQ in feed ingredient, compound feed for livestock, and compound feed for pets. The recovery rate was 70.09-119.76% and relative standard deviations were ≤ 18.91%. And the accuracy and precision were further verified through cross-validation between laboratories. The developed analytical method was used to monitor 414 domestically distributed and imported feeds.Particle separation is essential in a broad range of systems and has several biological applications. Microfluidics has emerged as a potentially transformational method for particle separation. The approach manipulates and separates particles at the micrometer scale by using well-defined microstructures and precisely managed force fields. Depending on the source of the principal manipulating forces, particle manipulation and separation in microfluidics may be classified as active or passive. Passive microfluidic devices depend on drag and inertial forces and microchannel structure, while active microfluidic systems rely on external force fields. Active microfluidics, in general, can properly control and place particles of interest in real time. Due to the low flow rate, the residual time required to apply an appropriate external manipulating force to the target particles is reduced, thereby limiting overall throughput. Passive microfluidics, on the other hand, has a simple architecture, robustness, and high tis review, the advantages and disadvantages of DEP-based separation devices will be examined. All these hybrid devices will be thoroughly examined and evaluated. Finally, a summary of present difficulties in the hybrid separation sector will be offered, as well as future suggestions and aspirations.In this study, the retention on three types of columns, an immobilized artificial membrane (IAM), a cholesterol-bonded and an octadecyl (C18) column, was applied for the prediction of skin permeability. The first two columns are biomimicking ones, which have certain components of the skin bound to the stationary phase, and were applied in HPLC, while the sub-2 µm C18 column was studied in UHPLC because of its fast features. Fifty-eight compounds were analyzed applying different mobile-phase compositions, with varying percentages of organic modifier on every column, to extrapolate the retention factor to a theoretically purely aqueous mobile phase (log kw). The retention factors, along with two sets of theoretical molecular descriptors, were used to model the skin permeability coefficient (log Kp) using multiple linear regression (MLR) and partial least squares (PLS) regression modelling. Although the retention factors (log k) on the IAM column showed a better correlation with the skin permeability, the overall best model was obtained by applying a stepwise MLR approach on the UHPLC parameters combined with some theoretical descriptors. This model showed a good fit, and on top has potential to accurately predict skin permeability values. Furthermore, the UHPLC method has the advantage of being fast and can thus be classified as a high-throughput approach.Size exclusion chromatography has become an essential tool for the protein therapeutics industry. Conceptually, it is a simple form of chromatography that is driven by entropy and sieving effects. An ideal size exclusion column would exhibit no adsorptive interactions between its internal surfaces and the solutes being analysed, but that is not easily achieved. To this end, we have studied the utility of three unique packing materials in pursuit of additional column chemistries that might be less prone to interacting with proteins. These packing materials were each prepared from bridged ethylene hybrid organic/inorganic particles but uniquely derivatized into either hydroxy terminated PEO bonded, methoxy terminated PEO bonded, or diol bonded packing materials. All three materials were packed into column hardware modified with hydrophilic hybrid surface technology (h-HST) so that packing material effects could be more clearly observed without any influence from the secondary interactions that can originate from metal hardware. Non-specific interactions were compared for various challenging protein samples in the presence of ammonium acetate (volatile) and phosphate buffered saline (non-volatile) buffers. It was reconfirmed that the h-HST column hardware mitigates a majority of non-desired secondary interactions. However, during studies on hydrophobic interactions, the new hydroxy terminated PEO packing material showed clear benefit to obtaining higher apparent recoveries to better ensure accurate aggregate quantitation. Further experiments were explored to show that a hydroxy terminated PEO column could be effectively paired with a mobile phase comprised of standard strength phosphate buffered saline to make a fast platform method capable of baseline resolving monoclonal antibody monomer and aggregate peaks within a 3 min analysis time.Empirically-supported psychotherapies for posttraumatic stress disorder (PTSD) are highly effective and recommended as first-line treatments, yet dropout rates from standard outpatient therapy are high. Intensive outpatient programs (IOPs) that provide these therapies in condensed format with complementary interventions show promise, as they have demonstrated similar efficacy and higher retention rates. The current study examined initial and long-term outcomes up to 12-months following a 2-week PTSD IOP involving daily prolonged exposure therapy (PE) and adjunctive interventions for veterans and military service members. Participants (N = 376) demonstrated high retention (91%) and large effect size reductions in self-reported PTSD and depression symptoms after two weeks. Small increases in symptoms occurred after 3 months but these stabilized and large reductions compared to baseline were maintained up to 12 months. Piecewise multilevel modeling indicated that demographic variables did not predict PTSD or depression symptom trajectories. Higher PTSD and depression severity at intake predicted higher symptomatology across timepoints and larger relative gains during treatment. Greater alcohol use prior to treatment was associated with higher PTSD symptomatology but did not affect the magnitude of gains. A history of childhood sexual abuse was associated with greater reduction in depression symptoms over treatment, although this effect faded over follow-up. Together these findings underscore the long-term effectiveness of a PE-based IOP across a diverse range of veterans and service members.Mothers and infants co-regulate their distance from one another at home. Continuous, naturalistic home observations of the changes in mother-infant distance were carried out in Japan and Scotland during infant ages of 0-1, 6-7, and 12-13 months. This study examined mutual distance-increasing and distance-reducing behaviours, referred to as parent-infant 'centrifugalism' and 'centripetalism'. Cultural differences emerged in the modes of mother-infant distance co-regulation. Scottish mothers were more active in initiating contact and leaving infants alone to sleep, whereas Japanese mothers showed stronger infant-centredness by maintaining physical contact with infants when they fell asleep and reacting to their crying when they woke up. Age differences were found relating to decrease in sleep and increase in object play in the middle of the first year, which resulted in more separation within a 0.5 m distance at 6-7 months, a compromise between closeness and distancing between mothers and awake infants. Cultural and age differences in the co-regulation of mother-infant distance were discussed in relation to the development of locomotion, object play, and intention-reading.Between 2017 and 2022, sediment labile organic matter, physico-chemical and nutrient content of the water column, biomass and C, N, P, S content of Sphaerococcus coronopifolius, a Rhodophyta that produced vegetative blooms in an area of the Orbetello lagoon (Italy) not far from the effluents of two land-based fish-farms, were examined and compared with an area even further away from that source where the species was not found. In order to understand the reasons for an important mat development in only one specific area, microcosm experiments were also carried out. Results suggest the species developed in dense and extensive mats under high orthophosphate and nitrate nitrogen ion concentrations conditions, behaving as an opportunistic species.