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In this work commercially available Fe3O4 NPs were coated with polyallylamine hydrochloride (PAH) and PAH functionalized with guanidinium groups (PAH–Gu) for investigating the phosphate adsorption properties under alkaline conditions. The coating can be prepared easily and rapidly and results in Fe3O4 NPs with improved properties related to phosphate binding and colloidal stability. At a low initial phosphate concentration (2 mg L−1), the novel Fe3O4@PAH–Gu material was able to remove phosphate rather independently of the pH condition (4.0, 3.6 and 3.7 mg g−1 at pH = 5, 8 and 10, respectively), whereas for the uncoated Fe3O4 NPs the amount of adsorbed phosphate drops by ＞75% upon changing from acidic to alkaline conditions (0.84 mg g−1 at pH = 10). Under alkaline conditions, the fastest adsorption was observed for Fe3O4@PAH–Gu followed by Fe3O4@PAH and Fe3O4. This can be related to the additional interaction forces due to the presence of primary amine groups (in PAH and PAH–Gu) and Gu groups (in PAH–Gu only) in coatings. Over 80% of the phosphate adsorbed on the novel Fe3O4@PAH–Gu material was successfully desorbed and the coated NPs were re-used over three adsorption/desorption cycles. This work will stimulate the design and preparation of functionalized polyelectrolytes for an extended area of applications, especially for the selective removal of target compounds from wastewater. [ABSTRACT FROM AUTHOR]

The recovery of carboxylic acids from fermentation broth is one of the main bottlenecks for the industrial production of bio-based esters. This paper proposes an alternative for the recovery of carboxylates produced by fermentations at pH values above the pKa of the carboxylic acid. In this approach, the aqueous carboxylate anion is recovered using anion exchange, followed by desorption and esterification with CO2-expanded alcohols. Using CO2-expanded methanol, we achieved a high desorption yield at 10 bar of CO2 and 20 °C. An ester yield of 1.03 ± 0.07 mol methyl acetate/acetatein was obtained for the combined desorption–esterification at 5 bar of CO2 and 60 °C. The proposed process has low chemical consumption and low waste production. The proposed process works, with a lower yield, for other carboxylates (e.g. lactate and succinate) and alcohols (e.g. ethanol). [ABSTRACT FROM AUTHOR]

Background: Bronchopneumonia (BP) in calves potentially causes systemic changes. Objectives: To describe metabolic, arterial blood gas, and acid‐base disorders in calves with BP diagnosed by thoracic ultrasound (TUS), Wisconsin score (WISC), and combinations of WISC and TUS. Animals: Two hundred thirty‐one dairy preweaned dairy calves from 13 dairy farms. Methods: Cross‐sectional study. Each calf sequentially underwent arterial blood gas evaluation, WISC score, venous sampling, and TUS. Calves were grouped based on a single diagnostic method and combination of WISC and 2 TUS cutoffs (≥1 cm; ≥3 cm) as healthy, upper respiratory tract infection, subclinical BP, and clinical BP. Results: Oxygenation and acid‐base variables were unaffected. Glucose concentration in TUS‐affected calves was significantly lower (P <.001) than in healthy calves (median ≥TUS1cm = 5.2 mmol/L 25%‐75% interquartile range [IQR] 4.5‐6.1,

Background Increased serum activity of CK isoenzymes and macroenzymes, and in particular of the brain isoenzyme ( CK- BB) has been reported in dogs with central nervous system ( CNS) disorders. However, no studies on the possible differences in serum activities of CK iso- or macroenzymes (Macro- CK1 and Macro- CK2) in different neurologic diseases are available. Objective The aim of this study was to describe the electrophoretic distribution of CK iso- and macroenzymes in dogs with CNS disorders in order to assess whether this distribution depends on a specific neurologic disease. Methods This study was done on sera from 45 dogs with neurologic diseases (degenerative, n = 7; idiopathic epilepsy [ IE], n = 14; inflammatory, n = 16; space occupying lesions [ SOL], n = 8) and from 10 clinically healthy dogs. The separation of serum CK isoenzymes and macroenzymes was performed using an automated electrophoretic method already validated in dogs. Results Compared with healthy dogs, dogs with CNS disorders had significantly higher total CK and CK- BB activities, and a significantly lower Macro- CK2 activity ( P < .001). Comparison of pathologic subgroups and healthy dogs revealed significant differences ( P < .01) in dogs with IE and inflammatory disorders for total CK activity, in all the subgroups for CK- BB ( P < .01), and in dogs with IE and SOL for Macro- CK2 ( P < .01). Conclusions The results of this study suggest that CK- BB is released by neurons damaged by inflammatory or degenerative conditions or due to compressive effects of SOL. However, the neurologic diseases cannot be differentiated based on CK- BB or Macro- CK2 activities, unless further studies allow the definition of diagnostic thresholds. [ABSTRACT FROM AUTHOR]