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This research presents a point‐of‐use (POU) water treatment technology utilizing metal/metallic surfaces based on Triply Periodic Minimal Surface (TPMS) structured filtration infills. Computational Fluid Dynamics modeling using Ansys CFX software is employed to analyze the behavior of Escherichia coli bacteria within a continuous liquid phase moving through the filtration infill, assess particle collision dynamics, and evaluate the efficiency of filtration, considering pressure drop as a fundamental factor in process energy consumption. TPMS infill meshes are coded in a Schwarz P shape using Python, and the Darcy‐Forchheimer equation is employed to determine the permeability and resistance loss coefficient of the infill geometry. The results indicate that the TPMS infill efficiently captures particles while introducing a negligible pressure drop into the system. It is found that a single 40 mm infill configuration is the most efficient, exhibiting a higher collision rate compared to the smaller 20 mm infill configuration and a lower pressure drop compared to the two 20 mm infill configurations in the series. Additionally, this study provides insights into the behavior of continuous fluid flow through TPMS infill in view of scaled‐up implementation, including the presence of recirculation zones that can be exploited to further enhance the collision rate of particles. [ABSTRACT FROM AUTHOR]

Abstract: The dose‐response of two horticultural plant species (Brassica chinensis L., and Helianthus annuus L.) to two light Rare Earth Elements (REEs), namely lanthanum and neodymium, in‐vitro, was investigated. The phytotoxicity of the studied REEs was determined by measuring the aboveground and belowground biomass of the plant parts, and the chlorophyll production. Based on these measurements, inhibition concentration causing 50 % decrease (IC50) in plant biomass and total chlorophyll were calculated. Moreover, the available ionic species of La and Nd in the media for plant uptake were predicted using Visual MINTEQ. The concentration of these elements were measured in different plant tissues to assay the ability of these plants to hyperaccumulate La and Nd. It was observed that La and Nd, at lower dosages (<∼100 mg/kg), had hormetic effects, respectively, on the shoot and root of H. annuus L. Also, Nd had stimulatory effects on the number of leaves and chlorophyll content of B. chinensis L. However, these two elements were toxic to both plants at higher media concentrations. Between the two plant species, H. annuus L. was more resistant to the studied REEs when compared to B. chinensis L. IC50 values of La for the roots and shoots of both plant species (139–201 mg/kg) were markedly smaller when compared to IC50 values of Nd (222–333 mg/kg). Thus, between the two assayed elements, La was more toxic to the plants. Translocation factors for La and Nd were not high enough to consider the plant species as hyperaccumulators. [ABSTRACT FROM AUTHOR]

Raman spectroscopy is a suitable monitoring technique for CHO cultivations. However, a thorough discussion of peaks, bands, and region assignments to key metabolites and culture attributes, and the interpretability of produced calibrations is scarce. That understanding is vital for the long‐term predictive ability of monitoring models, and to facilitate lifecycle management that comply with regulatory guidelines. Several fed‐batch lab‐scale mAb mammalian cultivations were carried out, with in situ Raman spectroscopy used for process state estimation and attribute monitoring. The goal was to evaluate its use as a process analytical technology (PAT) tool to detect residual glucose and lactate levels, understand their dynamics and interconversion, and eventually estimate key performance culture and product quality attributes. Glucose and lactate models were optimized up to 0.31 g L−1 with 3 Latent Variables (LVs) and 0.19 g L−1 (2 LVs) accuracy, respectively. Glutamine and product titer models, were not specific and accurate enough, even though indirect calibrations were obtained with a RMSEP of 0.12 g L−1 (4 LVs) and 0.29 g L−1 (5 LVs), respectively. A critical discussion and details about the extensive work done in calibration development and optimization are provided. Namely, considering a risk‐based selection of variability sources impacting sample spectra, executing designed experiments with spiked cultivations, and using advanced chemometric procedures for variable selection and model cross validation. A strategy is presented to evaluation Raman spectroscopy as a reliable PAT technology fit‐for industrial use. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:659–670, 2018 [ABSTRACT FROM AUTHOR]

Alkaline industrial wastes are considered potential resources for the mitigation of CO2 emissions by simultaneously capturing and sequestering CO2 through mineralization. Mineralization safely and permanently stores CO2 through its reaction with alkaline earth metals. These elements are found in a variety of abundantly available industrial wastes that have high reactivity with CO2, and that are generated close to the emission point-sources. Among all suitable industrial wastes, steelmaking slag has been deemed the most promising given its high CO2 uptake potential. In this paper, we review recent publications related to the influence of process parameters on the carbonation rate and conversion extent of steelmaking slags, comparing and analyzing them in order to define the present state of the art. Furthermore, the maximum conversions resulting from different studies are directly compared using a new index, the Carbonation Weathering Rate (CWR), which normalizes the results based on particle size and reaction duration. To date, the carbonation of Basic Oxygen Furnace steelmaking slag, under mild conditions, presents both the highest carbonation conversion and CWR, with values equal to 93.5% and 0.62 μm/min, respectively. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]

Phyco-valorization is the exploitation of microalgae and microalgal chemicals as valuable products. This paper discusses the optimization of microalgal bioreactor-based systems for C-phycocyanin pigment production. Various aspects contributing to system development and enhancement of phycocyanin productivity are described. A wide range of potential microalgal species have been identified for phycocyanin production; the selection of a species for mass culturing can be determined by desired bioreactor trophic mode and symbiotic relations. Research has demonstrated that species amenability to local lighting and climatic conditions, and to variations in bioreactor substrate concentrations and operational parameters, have significant impact on phycocyanin production. The simultaneous optimization of all factors contributing to system productivity may be accomplished efficiently through process modelling. A summary of established models for microalgal phycocyanin production is presented. A suggested strategy for increasing economic viability of phycocyanin production systems is their application in integrated resource recovery. Through the incorporation of phycocyanin productivity optimization principles within a phycoremediation process, the valorization of waste resources may be achieved. The simultaneous economic potential and environmentally-forward concept of phyco-valorization through phycocyanin production is a promising application of microalgal biotechnology awaiting further development for industrial implementation. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Background Manipulating the pig genome to increase compatibility with human biology may facilitate the clinical application of xenotransplantation. Genetic modifications to pig cells have been made by sequential recombination in fetal fibroblasts and liver-derived cells followed by cross-breeding or somatic cell nuclear transfer. The generation of pigs for research or organ donation by these methods is slow, expensive and requires technical expertise. A novel system incorporating the bacterial nuclease Cas9 and single-guide RNA targeting a 20 nucleotide site within a gene can be expressed from a single plasmid leading to a double-strand break and gene disruption. Coexpression of multiple unique single-guide RNA can modify several genetic loci in a single step. We describe a process for increasing the efficiency of selecting cells with multiple genetic modifications. Methods We used the CRISPR/ Cas system to target the GGTA1, CMAH and putative i Gb3 S genes in pigs that have been naturally deleted in humans. Cells lacking galactose α-1,3 galactose (α- Gal) were negatively selected by an IB4 lectin/magnetic bead. α- Gal negative multiplexed single-guide RNA-treated cells were used for somatic cell nuclear transfer ( SCNT) and transferred to fertile sows. We examined the levels of α- Gal and Neu5 Gc expression of 32 day fetuses and piglets and analyzed the targeted genes by DNA sequencing. Results Liver-derived cells treated with multiple single-guide RNA and selected for an α- Gal null phenotype were significantly more likely to also carry mutations in simultaneously targeted genes. Multiplex single-guide RNA-treated cells used directly for SCNT without further genetic selection produced piglets with deletions in the targeted genes but also created double- and triple-gene KO variations. CRISPR/ Cas-treated cells grew normally and yielded normal liters of healthy piglets via somatic cell nuclear transfer. Conclusions The CRISPR/ Cas system allows targeting of multiple genes in a single reaction with the potential to create pigs of one genetic strain or multiple genetic modifications in a single pregnancy. The application of this phenotypic selection strategy with multiplexed sg RNA and the Cas9 nuclease has accelerated our ability to produce and evaluate pigs important to xenotransplantation. [ABSTRACT FROM AUTHOR]

Bottom ashes produced from municipal solid-waste incineration are suitable for sorbent synthesis because of their inherent composition, high alkalinity, metastable mineralogy, and residual heat. This work shows that bottom ashes can be atom-efficiently converted into valuable sorbents without the need for costly and hazardous chemicals. The ashes were hydrothermally treated in rotary autoclaves at autogenic pH conditions to promote the conversion of precursor mineral phases into zeolites and layered silicate hydrates. Two main mineral phases were formed: katoite and sodium aluminum phosphate silicate hydrate. These mineral alterations are accompanied by a tenfold increase in specific surface area and a twofold reduction in average particle size. Performance evaluation of the new sorbents for Cd2+, Zn2+, and Pb2+ adsorption at pH 5 indicates sorption capacities of 0.06, 0.08, and 0.22 mmol g−1, respectively, which are similar to those of natural adsorbents and synthetic materials obtained from more demanding synthesis conditions. [ABSTRACT FROM AUTHOR]

Purpose To investigate the utility of whole-brain diffusion tensor imaging (DTI) in elucidating the pathogenesis of multiple sclerosis (MS) using the normal-appearing white matter (NAWM) of the corpus callosum (CC) as a marker of occult disease activity. Materials and Methods A high signal-to-noise ratio (SNR) and optimized entire brain DTI data were acquired in 26 clinically-definite relapsing and remitting multiple sclerosis (RRMS) patients and 32 age-matched healthy adult controls. The fractional anisotropy (FA) values of seven functionally distinct regions in the normal-appearing CC were compared between patients and controls. Results This study indicates that 1) there was a gender-independent FA heterogeneity of the functionally specialized CC segments in normal volunteers; 2) FA in the MS group was significantly decreased in the anterior ( P = 0.0039) and posterior ( P = 0.0018) midbody subdivisions of the CC, possibly due to a reduction of small-caliber axons; and 3) the FA of the genu of the CC was relatively intact in the MS patients compared to the healthy age-matched controls ( P = 0.644), while the splenium showed an insignificant trend of reduced FA values ( P = 0.248). The decrease in FA in any of the CC subdivisions did not correlate with disease duration (DD) or the expanded disability status scale (EDSS) score. Conclusion The preliminary results are consistent with published histopathology and clinical studies on MS, but not with some published DTI reports. This study provides insights into the pathogenesis of MS, and the role played by compromised axonal integrity in this disease. J. Magn. Reson. Imaging 2005;21:735-743. © 2005 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

The modern world's major challenges, such as global warming, air pollution, and increasing energy demands, escalate the importance of sustainable development and transition toward renewables using innovative and environmentally friendly solutions, such as intensifying chemical processes, to reduce carbon footprints effectively. Aiming to enhance the process toward negative carbon emissions, this perspective explores the intensified membrane reactors for reducing the energy intensity of converting biogas into methanol, a versatile chemical feedstock, and renewable liquid fuel. Syngas and methanol synthesis processes, catalysts, and membranes were explored, and novel reactor designs were proposed. Introduction of selective membranes into the catalytic reaction zone to combine synthesis separation steps could enhance the system efficiency and intensify the process by recycling energy and materials, besides reducing costs and required energy for the separation process: the continuous harnessing of products shifts reactions toward desired species while recycling energy and materials enhances the process efficiency, and separating water from methanol reduces the required energy and costs of extra processes for methanol separation. The successful implementation of this technology holds significant promise for sustainable developments in producing chemicals and renewable fuel from renewable biogas and reducing methane and carbon dioxide emissions toward achieving carbon‐negative technologies. [ABSTRACT FROM AUTHOR]