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Premise A comparison of methods using different materials to exclude light from stems to prevent stem CO2 exchange (i.e., photosynthesis), without affecting stem conductance to water vapor, surface temperature, and relative humidity, was conducted on stems of avocado trees in California. Methods and Results The experiment featured three materials: aluminum foil, paper‐based wrap, and mineral‐based paint. We examined stem CO2 exchange with and without the light exclusion treatments. We also examined stem surface temperature, relative humidity, and photosynthetic active radiation (PAR) under the cover materials. All materials reduced PAR and stem CO2 exchange. However, aluminum foil reduced stem surface temperature and increased relative humidity. Conclusions Methods used to study stem CO2 exchange through light exclusion have historically relied on methods that may induce experimental artifacts. Among the methods tested here, mineral‐based paint effectively reduced PAR without affecting stem surface temperature and relative humidity around the stem. Resumen Premisa Una comparación de diferentes métodos utilizando distintos materiales para bloquear la luz de los tallos y así reducir el intercambio de CO2 (fotosíntesis) sin afectar la conductancia del tallo al vapor de agua, su temperatura superficial y la humedad relativa fue llevado a cabo en tallos de árboles de aguacate en California. Metodología y resultados El experimento se llevó a cabo utilizando tres materiales: papel de aluminio, papel para envoltura y pintura a base de minerales. Se examinó el intercambio de CO2 de los tallos con y sin los materiales de bloqueo de la luz. También se examinó la temperatura de la superficie del tallo, la humedad relativa y la radiación fotosintéticamente activa (PAR por sus siglas en inglés) debajo de los materiales usados para bloquear la luz. Todos los materiales redujeron PAR y el intercambio de CO2 del tallo. Sin embargo, el papel aluminio redujo también la temperatura de la superficie del tallo y aumento la humedad relativa. Conclusiones Los métodos utilizados para estudiar el intercambio de CO2 de los tallos con el ambiente a través del bloqueo de la luz han sido métodos que pueden generar alteraciones no deseadas. Entre los métodos evaluados aquí, la pintura de base mineral fue efectiva reduciendo PAR sin alterar la temperatura superficial del tallo ni la humedad relativa alrededor de este.

BACKGROUND AND AIMS: When sunlight was excluded (opacity coefficient 100%) from fruitset until maturity, the red grape cultivar Jingxiu failed to colour while Jingyan (Jingxiu × white grape Xiangfei) developed red colour. The aim of this study was to gain insight into the genetic background that may be responsible for sunlight‐dependent versus sunlight‐independent anthocyanin biosynthesis in berry skin. METHODS AND RESULTS: The composition and concentration of anthocyanins via high‐performance liquid chromatography, and the transcriptional level of structural and regulatory genes via real‐time polymerase chain reaction were investigated. Light exclusion suppressed all the anthocyanins in Jingxiu berry skin, but did not change the proportion of the various anthocyanins in Jingyan. UDP‐glucose:flavonoid 3‐O‐glucosyltransferase (UFGT) and a v‐myb myeloblastosis viral oncogene homolog transcription factor (VvMYBA1) were expressed at a high level in sunlight‐exposed Jingxiu, sunlight‐exposed and excluded Jingyan, but not in sunlight‐excluded Jingxiu, which correlated with phenotypic colouration (red vs not red). There was no difference in the DNA sequence of the VvMYBA1b promoter region between Jingxiu and Jingyan. CONCLUSIONS: The regulatory gene VvMYBA1 is involved in the regulation of anthocyanin biosynthesis via the structural gene UFGT, while there must be some other regulatory factors or post‐transcriptional regulation mechanisms that differentially regulated VvMYBA1 in Jingxiu and Jingyan in response to sunlight. SIGNIFICANCE OF THE STUDY: The primary control mechanism of anthocyanin biosynthesis in the absence of sunlight would provide information for breeding sunlight‐independent red grape cultivars, which would be valuable for cultivation in areas with low sunlight, e.g. glasshouses or other covered cropping.

A catalytic antibody has multiple functions compared with a monoclonal antibody because it possesses unique features to digest antigens enzymatically. Therefore, many catalytic antibodies, including their subunits, have been produced since 1989. The catalytic activities often depend on the preparation methods and conditions. In order to elicit the high catalytic activity of the antibodies, the most preferable methods and conditions, which can be generally applicable, must be explored. Based on this view, systematic experiments using two catalytic antibody light chains, #7TR and H34, were performed by varying the purification methods, pH, and chemical reagents. The experimental results obtained by peptidase activity tests and kinetic analysis, revealed that the light chain’s high catalytic activity was observed when it was prepared under a basic condition. These data imply that a small structural modulation of the catalytic antibody occurs during the purification process to increase the catalytic activity while the antigen recognition ability is kept constant. The presence of NaCl enhanced the catalytic activity. When the catalytic light chain was prepared with these preferable conditions, #7TR and H34 hugely enhanced the degradation ability of Amyloid-beta and PD-1 peptide, respectively.

We analyzed softwood and hardwood bleached kraft pulps (SBKP and HBKP, respectively), and Japanese cedar ( Cryptomeria japonica ) celluloses prepared from wood powders using delignification, hemicellulose removal, and dilute acid hydrolysis. For sample preparation, each sample was dissolved in 8% (w/w) lithium chloride/ N,N -dimethylacetamide (LiCl/DMAc), after the sample was soaked in ethylenediamine (EDA) and the EDA was exchanged with DMAc through methanol. These solutions were diluted to 1% (w/v) LiCl/DMAc and subjected to size-exclusion chromatography (SEC) combined with multiangle laser light scattering and viscometry analyses. SEC/multiangle laser light scattering and SEC/viscometry use different principles to determine the molecular structures of polymers dissolved in LiCl/DMAc. Both methods showed that SBKP celluloses with high molar masses had branched structures, whereas HBKP celluloses had linear structures as like cotton, bacterial, tunicate, and algal celluloses. Conventionally, viscosity-average molar masses or viscosity-average degrees of polymerization of SBKP and HBKP are obtained by capillary viscometry using a 0.5 M copper ethylenediamine hydroxide (cuen) solution. Because SBKP and HBKP have different cellulose structures (branched and linear molecules, respectively), their viscosity-average molar masses and viscosity-average degrees of polymerization should not be calculated using the same Mark–Houwink–Sakurada equation. Graphical abstract

The dissolution process of cellulose aerogels is an important part of their production. However, if the cellulose is severely degraded during the dissolution process, the quality may be low. To evaluate the degradation of cellulose during the dissolution process using calcium thiocyanate, the hydrolysis and oxidation of cellulose were evaluated by the change in absolute molecular weight and by the changes in the content of carboxyl and carbonyl groups introduced into the cellulose hydroxyl group, respectively. A noteworthy hydrolysis phenomenon was found in the cellulose dissolution process. The rate of hydrolysis increased as the number of hydrates in calcium thiocyanate decreased and as the reaction temperature increased. In the case of the reaction with calcium thiocyanate containing six hydrates, the time to reach a 50% loss of the degree of polymerization of cellulose reduced from 196 to 47 min as the reaction temperature was increased from 100 to 120 °C; however, the effect on oxidation was not significant. The Brunauer–Emmett–Teller (BET) surface area reduced as the degree of cellulose polymerization decreased. Therefore, it is necessary to consider how the cellulose degradation occurring during the cellulosic dissolution process can affect the quality of the final cellulose aerogels.

Recombinant adeno-associated viruses (rAAVs) play a pivotal role in the treatment of genetic diseases. However, current production and purification processes yield AAV-based preparations that often contain unwanted empty, partially filled or damaged viral particles and impurities, including residual host cell DNA and proteins, plasmid DNA, and viral aggregates. To precisely understand the composition of AAV preparations, we systematically compared four different single-stranded AAV (ssAAV) and self-complementary (scAAV) fractions extracted from the CsCl ultracentrifugation gradient using established methods (transduction efficiency, analytical ultracentrifugation (AUC), quantitative and digital droplet PCR (qPCR and ddPCR), transmission electron microscopy (TEM) and enzyme-linked immunosorbent assay (ELISA)) alongside newer techniques (multiplex ddPCR, multi-angle light-scattering coupled to size-exclusion chromatography (SEC-MALS), multi-angle dynamic light scattering (MADLS), and high-throughput sequencing (HTS)). Suboptimal particle separation within the fractions resulted in unexpectedly similar infectivity levels. No single technique could simultaneously provide comprehensive insights in the presence of both bioactive particles and contaminants. Notably, multiplex ddPCR revealed distinct vector genome fragmentation patterns, differing between ssAAV and scAAV. This highlights the urgent need for innovative analytical and production approaches to optimize AAV vector production and enhance therapeutic outcomes.

Poly(γ-glutamic acid) (PGA) is a biopolymer produced by Bacillus spp. via the γ-amide linkages of d- and/or l-glutamate. Although high-molecular-weight (HMW) PGA possesses many attractive properties, such as flocculating, wound healing, and immune-stimulating effects, no studies have reported factors useful for increasing the molecular weight of PGA during microbial production. PgsB, PgsC, and PgsA are the minimum protein sets required for PGA production in B. subtilis, and PgsE improves PGA productivity. Analysis by size-exclusion chromatography combined with multiangle laser light scattering revealed that the molecular weight of PGA was Mw = 2,900,000 g mol−1 and predominantly Mw = 47,000 g mol−1 in preparations derived from B. subtilis cells with and without pgsE, respectively. PgsE may be required to increase the molecular weight of PGA.Poly(γ-glutamic acid) (PGA) is a biopolymer produced by Bacillus spp. via the γ-amide linkages of d- and/or l-glutamate. PgsB, PgsC, and PgsA are the minimum protein set required for PGA production in B. subtilis, and PgsE improves PGA productivity. Analysis by size-exclusion chromatography combined with multiangle laser light scattering revealed that the molecular weight of PGA was Mw = 2,900,000 g mol−1 or predominantly Mw = 47,000 g mol−1 in preparations derived from B. subtilis cells with or without pgsE, respectively. PgsE may be required to increase the apparent molecular weight of PGA.

In this study, the influence of homehold composting conditions on the molecular and supramolecular structure of polylactide (PLA) in the form of spun-bonded nonwovens was investigated. Nonwoven samples were studied using size-exclusion chromatography coupled with multiangle laser light scattering detection, wide-angle X-ray diffraction, differential scanning calorimetry and Fourier transform infrared spectroscopy. In addition, the physical and mechanical properties of the nonwovens before and after composting were determined. The results show the varying degree of influence of the prepared compost mixtures of soil with common horticultural additives, such as chalk, commercially available agents, cow manure and chicken litter, on the molecular and supramolecular structure of PLA and its degradation rate. The obtained experiment explained which popular homehold agent had the strongest affect on the PLA nonwoven dedicated for agriculture use in the first period of season composting (first 6 months).

Reactive extrusion of poly( L -lactide) (PLLA) was carried out in the presence of a small amount of various peroxides with relatively slow decomposition rates. The resulting crosslinked, four-armed randomly branched PLLA (χ-PLLA) was characterized by size exclusion chromatography equipped with multiangle laser light scattering (SEC-MALS), and the results were interpreted according to the type of peroxide used. A new component with a higher molecular weight than the original PLLA was observed in the SEC-MALS chromatograms of the χ-PLLA. The weight-averaged molecular weight ( M w ) of the χ-PLLA was found to increase with increasing effective radical number per PLLA precursor ( n ), where n is the overall hydrogen abstraction ability of peroxide times the mole ratio of radical to PLLA precursor molecule. This implies that the hydrogen abstraction ability is a good index for the crosslinking efficiency of PLLA. The extent of branching of χ-PLLA was estimated by the shrinking factor, g =〈 R g 2 〉 b /〈 R g 2 〉 l , and rationalized with n , where 〈 R g 2 〉 b and 〈 R g 2 〉 l are the mean square radii of gyration of branched and linear polymers with the same molecular weight, respectively. The nucleation and overall crystallization rate of χ-PLLA in the nonisothermal crystallization from the melt was discussed from the viewpoints of branching and entanglement density. Reactive extrusion of poly( L -latctide) (PLLA) was carried out in the presence of a small amount of various peroxides. The resulting crosslinked, four-armed randomly branched PLLA (χ-PLLA) was characterized by size exclusion chromatography fitted with multiangle laser light scattering and rationalized with the type of peroxide used. The extent of branching of χ-PLLA was estimated by the shrinking factor and was rationalized with the effective radical number per PLLA precursor n . The nucleation and overall crystallization rate of χ-PLLA in the nonisothermal crystallization from the melt was rationalized with branching and entanglement density.

Streptococcus pneumoniae bacterial infection can cause serious diseases. Among more than 90 known streptococcus pneumoniae serotypes, more than 30 can cause invasive pneumococcal diseases that could lead to morbidity and mortality. Initially, a 23-valent polysaccharide vaccines (PPSV) PNEUMOVAX®23, was developed to generate an antigen-specific immune response and prevent diseases caused by these pneumoniae serotypes. Later, pneumococcal conjugate vaccines (PCV), such as PREVNAR® and VAXNEUVANCE™ have been developed to offer a more robust immune response in the pediatric population. In our effort to develop novel pneumococcal conjugate vaccines, each serotype of pneumococcal polysaccharide (Ps) is conjugated to a detoxified diphtheria toxin carrier protein CRM197 to form a monovalent conjugate (MVC). MVCs from multiple serotypes are formulated with vaccine adjuvant to form a multi-valent vaccine drug product. During the product development, critical attributes including conjugate molecular weight (Mw), protein and polysaccharide concentration, have been used to monitor process and product quality. To measure these attributes, a size-exclusion chromatography (SEC) method was developed with a series of in-line detectors including UV, multi-angle light scattering (MALS) and refractive index (RI). This SEC-UV-MALS-RI method is employed to characterize and monitor process intermediates and product during process development and for product release and stability testing. With this, we have expanded the multi-attribute SEC method to a 15-valent pneumococcal conjugate vaccine.