A pilot scale study of reverse osmosis for the purification of condensate arising from distillery stillage concentration plant

Reverse osmosis (RO) is an interesting process to eliminate small organic solutes (carboxylic acids and alcohols) from distillery condensates before recycling them into the fermentation step. This work investigates the influence of transmembrane pressure, pH and volume reduction factor (VRF) on the efficiency of reverse osmosis treatment of condensate from distillery stillage concentration at pilot scale using three pre-selected membranes (CPA2 and ESPA2 from Hydranautics, BW30 from DOW). Performances were assessed according to permeate flux, solutes rejection and abatement of fermentation inhibition. Transmembrane pressure increase leads to an increase of these three parameters with a plateau for rejections and abatement at 20 bar; however, in order to comply with membranes manufacturer's recommendations and to limit or delay polarization and fouling, it was decided to keep the permeate flux below a value of 30 L h⁻¹ m⁻². This corresponded to a maximum pressure of 10 bar for CPA2 and ESPA2 membranes and 25 bar for BW30 membrane. pH increase leads to a diminution of permeate flux and an increase of carboxylic acids rejection whatever the membrane; nevertheless, no abatement of fermentation inhibition is observed. Increasing VRF provokes a decrease of the permeate flux. Although local rejections are stable, the mean rejection assessed with the raw condensate (feed) and the mean permeate decreases. However, the fermentation inhibition remains under 10% up to a VRF of 8. BW30 membrane exhibits the highest rejections and inhibition abatement. On the basis of the pilot scale results with the BW30 membrane, a preliminary estimation of the membrane area is proposed for an industrial plant with 100 m³ h⁻¹ of condensate flow rate and the optimized parameters (pressure 25 bar, no pH modification, VRF 4 and 8).     

Comparison between electrocoagulation and chemical precipitation for metals removal from acidic soil leachate

This paper provides a quantitative comparison between electrocoagulation and chemical precipitation based on heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) removal from acidic soil leachate (ASL) at the laboratory pilot scale. Chemical precipitation was evaluated using either calcium hydroxide or sodium hydroxide, whereas electrocoagulation was evaluated via an electrolytic cell using mild steel electrodes. Chemical precipitation was as effective as electrocoagulation in removing metals from ASL having low contamination levels (30 mg Pbl(-1) and 18 mg Znl(-1)). For ASL enriched with different metals (each concentration of metals was initially adjusted to 100 mg l(-1)), the residual Cr, Cu, Pb and Zn concentrations at the end of the experiments were below the acceptable level recommended for discharge in sewage urban works (more than 99.8% of metal was removed) using either electrocoagulation or chemical precipitation. Cd was more effectively removed by electrochemical treatment, whereas Ni was easily removed by chemical treatment. The cost for energy, chemicals and disposal of metallic residue of electrocoagulation process ranged from USD 8.83 to 13.95 tds(-1), which was up to five times lower than that recorded using chemical precipitation. Highly effective electrocoagulation was observed as the ASL was specifically enriched with high concentration of Pb (250-2000 mg Pbl(-1)). More than 99.5% of Pb was removed regardless of the initial Pb concentration imposed in ASL and, in all cases, the residual Pb concentrations (0.0-1.44 mg l(-1)) were below the limiting value (2.0 mg l(-1)) for effluent discharge in sewage works.     

Improved nursing home end-stage renal disease patient participation in physical therapy with onsite,more frequent dialysis

Introduction

For end-stage renal disease (ESRD) patients residing in skilled nursing facilities (SNFs), the logistics and physical exhaustion of life-saving hemodialysis therapy often conflict with rehabilitation goals. Integration of dialysis care with rehabilitation programs in a scalable and cost-efficient manner has been a significant challenge. SNF-resident ESRD patients receiving onsite, more frequent hemodialysis (MFD) have reported rapid post-dialysis recovery. We examined whether such patients have improved Physical Therapy (PT) participation.

Methods

We conducted a retrospective electronic medical records review of SNF-resident PT participation rates within a multistate provider of SNF rehabilitation care from January 1, 2022 to June 1, 2022. We compared three groups: ESRD patients receiving onsite MFD (Onsite-MFD), ESRD patients receiving offsite, conventional 3×/week dialysis (Offsite-Conventional-HD), and the general non-ESRD SNF rehabilitation population (Non-ESRD). We evaluated physical therapy participation rates based on a predefined metric of missed or shortened (<15 min) therapy days. Baseline demographics and functional status were assessed.

Findings

Ninety-two Onsite-MFD had 2084 PT sessions scheduled, 12,916 Non-ESRD had 225,496 PT sessions scheduled, and 562 Offsite-Conventional-HD had 9082 PT sessions scheduled. In mixed model logistic regression, Onsite-MFD achieved higher PT participation rates than Offsite-Conventional-HD (odds ratio: 1.8, CI: 1.1–3.0; p < 0.03), and Onsite-MFD achieved equivalent PT participation rates to Non-ESRD (odds ratio: 1.2, CI: 0.3–1.9; p < 0.46). Baseline mean ± SD Charlson Comorbidity score was significantly higher in Onsite-MFD (4.9 ± 2.0) and Offsite-Conventional-HD (4.9 ± 1.8) versus Non-ESRD (2.6 ± 2.0; p < 0.001). Baseline mean self-care and mobility scores were significantly lower in Onsite-MFD versus Non-ESRD or Offsite-Conventional-HD.

Discussion

SNF-resident ESRD patients receiving MFD colocated with rehabilitation had higher PT participation rates than those conventionally dialyzed offsite and equivalent PT participation rates to the non-ESRD SNF-rehabilitation general population, despite being sicker, less independent, and less mobile. We report a scalable program integrating dialysis and rehabilitation care as a potential solution for ESRD patients recovering from acute hospitalization.     

Pressure and Chemical Unfolding of an α-Helical Bundle Protein: The GH2 Domain of the Protein Adaptor GIPC1

When combined with NMR spectroscopy, high hydrostatic pressure is an alternative perturbation method used to destabilize globular proteins that has proven to be particularly well suited for exploring the unfolding energy landscape of small single-domain proteins. To date, investigations of the unfolding landscape of all-β or mixed-α/β protein scaffolds are well documented, whereas such data are lacking for all-α protein domains. Here we report the NMR study of the unfolding pathways of GIPC1-GH2, a small α-helical bundle domain made of four antiparallel α-helices. High-pressure perturbation was combined with NMR spectroscopy to unravel the unfolding landscape at three different temperatures. The results were compared to those obtained from classical chemical denaturation. Whatever the perturbation used, the loss of secondary and tertiary contacts within the protein scaffold is almost simultaneous. The unfolding transition appeared very cooperative when using high pressure at high temperature, as was the case for chemical denaturation, whereas it was found more progressive at low temperature, suggesting the existence of a complex folding pathway.     

PD-L1 Expression in 65 Conjunctival Melanomas and Its Association with Clinical Outcome

Conjunctival melanoma (CM) iss a rare and aggressive tumour that is increasing in frequency. The prognostic value of PD-L1 expression, alone or in combination with CD8 and PD-1 expression and the BRAF and NRAS status, has not been determined in CM to date. We evaluated the expression of PD-L1, CD8, PD-1 in CM and investigated whether there was an association between the expression of these markers and the BRAF and NRAS molecular profile as well as some clinico-pathological criteria. A total of sixty-five CM were assessed for PD-L1, PD-1, and CD8 expression by immunohistochemistry (IHC) and for BRAF and NRAS genomic alterations using molecular biology techniques and anti-BRAF and anti-NRAS antibodies. PD-L1 expression in tumour cells (TC) was very low or absent but detected in tumour-infiltrating immune cells (IC). A correlation was observed between the expression of PD-L1, CD8, and PD-1 in IC. No correlation between PD-L1 expression (in tumour and/or immune cells) and BRAF or NRAS mutations was observed. PD-L1 expression in IC correlated with a higher pTNM stage and PD-L1 expression in TC with worse disease-specific survival. PD-L1 expression is a potential prognostic biomarker that correlates with poor prognosis in CM patients.     

The synthesis and characterization of copper-based metal–organic framework/graphite oxide composites

New composites of a copper-based metal–organic framework and graphite oxide were synthesized with different ratios of HKUST-1 (also called MOF-199) and graphite oxide. These compounds, as well as the parent materials, were characterized by X-ray diffraction, sorption of nitrogen, FT-IR spectroscopy, thermal analyses, scanning electron microscopy, and sorption of hydrogen. The composites exhibit features similar to HKUST-1 as well as an increased porosity compared to the parent materials. The formation of new small pores is demonstrated by an increase in the hydrogen uptake. The results suggest that the building process of the composites occurs via the reaction/binding of the copper dimers from the HKUST-1 with/to the functional groups in graphite oxide (epoxy, carboxylic, hydroxylic, sulfonic).     

The Multivalent Effect in Glycosidase Inhibition: Probing the Influence of Valency,Peripheral Ligand Structure,and Topology with Cyclodextrin‐Based Iminosugar Click Clusters

In view of recent reports of a strong multivalent effect in glycosidase inhibition, a library of β‐CD‐based multivalent iminosugars has been efficiently synthesized by way of Cu^I‐catalyzed azide–alkyne cycloaddition (CuAAC). In combination with the first application of isothermal titration calorimetry (ITC) experiments to the study of multivalent iminosugar–enzyme interactions, the inhibition properties of these click clusters were evaluated on a panel of glycosidases. The structural parameters that were varied include valency, peripheral ligand structure, and topology. The inhibition results obtained with the iminosugar clusters further highlight the importance of multivalency in the inhibition of α‐mannosidase. Generally, the evaluated multivalent iminosugars displayed comparable thermodynamic signatures of binding towards α‐mannosidase (Jack bean): that is, large negative enthalpies of complexation coupled with small entropies of either sign. In addition, the enthalpy–entropy compensation observed in all tested cases may be attributed to a common mechanism of dissociation for the enzyme–multivalent iminosugar interactions. The measured binding stoichiometries indicated that each iminosugar cluster interacts with no more than one protein molecule.