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Mineral scaling persists in many water treatment processes. More specifically, it can significantly reduce the efficacy of aromatic polyamide (PA) membranes during reverse osmosis (RO) water treatment. Previous studies have integrated hydrophilic materials, such as polyethylene glycol (PEG), onto RO membranes to combat scaling from generally hydrophobic feed water constituents; however, there are still outstanding knowledge gaps regarding the interplay of the modified membrane surface chemistry and the water chemistry in complex RO feed waters. In this work, we have investigated the mechanisms of hydrophilic PEG-grafted PA membranes in reducing mineral scaling from calcium carbonate (CaCO3) and calcium sulfate (CaSO4) in the presence of humic acid (HA). Based on surface and solution analyses, we found that colloidal formation was significantly reduced on PA–PEG surfaces in systems without HA. When HA was introduced, CaCO3 scaling was reduced on both virgin and PA–PEG membrane surfaces; while, interestingly, synergistic PEG–HA–CaSO4 interactions increased CaSO4 colloidal formation on PA–PEG membranes. Promoted CaSO4 formation results from a high negative surface charge near the PEG-modified membrane surface when HA and SO42− are present, attracting more Ca2+ to form CaSO4. The results of this work provide new information about colloidal formation at water–membrane interfaces for designing better PEG and PEG-based scale-resistant desalination membranes. [ABSTRACT FROM AUTHOR]

Pseudomembranous colitis (PMC) is a nosocomial and opportunistic infection caused by Clostridium difficile. PMC is related to the use of antibiotics leading to intestinal dysbiosis and an overgrowth of C. difficile. Metronidazole or vancomycin is considered to be the standard therapy for the management of PMC. However, PMC has a 15%-30% recurrence rate and can be refractory to standard treatments, resulting in morbidity and mortality. Here we describe a patient who experienced refractory PMC who was treated with fecal microbiota transplantation. A 69-year-old woman was admitted to the hospital with consistent abdominal pain and diarrhea, which had been present for 5 months. She was diagnosed with PMC by colonoscopy and tested positive for C. difficile toxin. Even though she took metronidazole for 10 days, followed by vancomycin for 4 weeks, her symptoms did not improve. Because of her recurrent and refractory symptoms, we decided to perform fecal microbiota transplantation. Fifty grams of fresh feces from a donor were obtained on the day of the procedure, mixed with 500 mL of normal saline, and then filtered. The filtered solution was administered to the patient's colon using a colonoscope. After the procedure, her symptoms rapidly improved and a follow-up colonoscopy showed that the PMC had resolved without recurrence. [ABSTRACT FROM AUTHOR]

Background: Metformin is considered the first choice oral treatment for type 2 diabetes patients in the absence of contraindications. Rarely, life-threatening complications associated with metformin treatment are seen in some patients with underlying diseases. The aim of this study was to further investigate the clinical profiles and risk factors for metformin-associated lactic acidosis (MALA) and the treatment modalities according to survival. Methods: To identify MALA, we performed a retrospective study in seven diabetic patients who were taking metformin and had been diagnosed with lactic acidosis at Inha University Hospital between 1995 and 2012. For each patient, we recorded the age, sex, daily metformin dosage, laboratory test results, admission diagnosis, and risk factors. Also, concurrent conditions, treatment modalities, and outcomes were evaluated. Results: Six patients had risk factors for lactic acidosis before admission. All patients had renal impairment on admission as a precipitating risk factor. Five patients survived and two patients died despite early renal replacement therapy. Older patients tended to have a poorer prognosis. Conclusion: Renal function must be monitored in elderly type 2 diabetes mellitus patients with underlying diseases and conditions causing renal impairment who begin metformin treatment. Accurate recognition of MALA and initiation of renal replacement are essential for treatment. [ABSTRACT FROM AUTHOR]

The article focuses on a study of geochemical reactions resulting from geologic carbon sequestration (GCS) and how this impacts the environmental sustainability of GCS. It states various GCS methods include direct injection of carbon dioxide (CO2) into unminable coal seams, nearly depleted gas and oil reservoirs, and deep saline aquifers, with deep saline aquifers estimated to possess the greatest carbon storage and sequestration capacity. It mentions that the solubility of injected supercritical CO2 dissolved into brine increases nonlinearly with increasing pressure and temperature while it decreases with higher salt content. It comments on the dissolution and precipitation of caprocks and formation rocks, which primarily consist of clay minerals, carbonate, silicate and aluminosilicate.

For sustainable geologic CO2sequestration(GCS), itis important to understand the effects of temperature and CO2pressure on mica’s dissolution and surface morphologicalchanges under saline hydrothermal conditions. Batch experiments wereconducted with biotite (Fe-end member mica) under conditions relevantto GCS sites (35–95 °C and 75–120 atm CO2), and 1 M NaCl solution was used to mimic the brine. With increasingtemperature, a transition from incongruent to congruent dissolutionof biotite was observed. The dissolution activation energy based onSi release was calculated to be 52 ± 5 kJ mol–1. By comparison with N2experiments, we showed that CO2injection greatly enhanced biotite’s dissolution andits surface morphology evolutions, such as crack formation and detachmentof newly formed fibrous illite. For biotite’s dissolution andmorphological evolutions, the pH effects of CO2were differentiatedfrom the effects of bicarbonate complexation and CO2intercalation.Bicarbonate complexation effects on ion release from biotite werefound to be minor under our experimental conditions. On the otherhand, the CO2molecules in brine could get into the biotiteinterlayer and cause enhanced swelling of the biotite interlayer andhence the observed promotion of biotite surface cracking. The crackingcreated more reactive surface area in contact with brine and thusenhanced the later ion release from biotite. These results providenew information for understanding CO2–brine–micainteractions in saline aquifers with varied temperatures and CO2pressures, which can be useful for GCS site selection andoperations. [ABSTRACT FROM AUTHOR]

Photothermal membrane distillation (PMD) has received increased attention for water desalination because it uses abundant sunlight as its main energy source. It can also be implemented in a modular configuration and work well for decentralized communities. Here we present a multi-layer stacked membrane module with airgaps that can reduce conductive heat loss and recover latent heat. The membrane is synthesized by a simple and scalable spray-coating method that prepared by graphene nanosheets deposition onto a hydrophobic polytetrafluoroethylene (PTFE) membrane with polymerized dopamine (PDA) and trichloro(1H,1H,2H,2H-perfluorooctyl) silane (FTCS). Graphene nanosheets are employed as a photothermal material because of its broad light absorption in the solar spectrum and efficient photothermal conversion. To maximize the water flux, the airgap thickness was optimized, and multiple heat recovery layers were stacked. Using the optimized airgap and four stacked layers, we achieved a high water flux of 1.17 kg/m2/h under 0.75 kW/m2, equivalent to 105% solar conversion efficiency, which is the highest efficiency reported among all PMD studies (20–70%). To predict the water flux, we further constructed a theoretical model to estimate the membrane surface temperatures that are photothermally heated, which will be helpful in understanding and optimizing future PMD systems. The high efficiency of the multi-layer stacked PMD module in this study bespeaks its great promise as a sustainable and off-grid desalination technique. ga1 With an efficient graphene nanosheet-based photothermal membrane, we demonstrate that the performance of the photothermal membrane distillation was largely improved by effectively recovering latent heat generated during condensation of vapor. Using the optimized airgap and four stacked layers, we achieved a high water flux of 1.17 kg/m2/h under 0.75 kW/m2, equivalent to 105% solar conversion efficiency. • Graphene-based photothermal membranes were fabricated with a simple spray coating. • In our novel multi-layer stacked module, latent heat was efficiently recovered. • With an optimal setting, we achieved the high solar-to-water efficiency (~ 105%). • Synthesized membranes were mechanically and chemically robust for long-term use. [ABSTRACT FROM AUTHOR]

Solar energy holds great promise for sustainable desalination to alleviate global water scarcity. Recently developed solar steam generation relying on interfacial evaporators has high solar energy-to-steam efficiency (60–90%), but its vapor collection efficiency is low, typically ~30%. Here, we present a solar-driven photothermal membrane distillation (PMD) system that offers easy and highly efficient clean vapor generation, condensation, and collection. The new photothermal membrane is thermally-engineered to incorporate a bilayer structure composed of two environmentally-sustainable materials, polydopamine (PDA) particles and bacterial nanocellulose (BNC), and it achieved a permeate flux of 1.0 kg m−2 h−1 under 1 sun irradiation and a high solar energy-to-collected water efficiency of 68%. The thermally-engineered strategy of using a bilayer structure ensures superb optical/photothermal activities, maximized membrane porosity (~93%), and reduced conductive heat transfer, thus increasing the thermal efficiency of the membrane. The strong chemically-bonded fluorosilane functional groups on the membrane surface provide stable hydrophobicity and high salt rejection (>99.9%). Moreover, under solar irradiation, the membrane shows effective interfacial photothermal disinfection to kill bacteria, enabling easy cleaning and increasing its lifespan. Using solar energy, the PMD system presented here can provide advantageous decentralized desalination for remote areas, and can support resilient community development. Image 1 [ABSTRACT FROM AUTHOR]

Abstract The somatic BRCA1 or BRCA2 Pathogenic Variant (PV)/Likely PV (LPV) from Next Generation Sequencing (NGS) is the most important biomarker for PARP inhibitor use and maintenance-targeted therapies. A discrepancy in the detection rates of BRCA1 and BRCA2 PV/LPV was identified among the NGS platforms. The objective of this study was to compare the somatic BRCA results from two distinct platforms using the same cohort and to identify the causes of these differences. Patients with epithelial ovarian cancer who concurrently underwent tumor NGS using two different platforms between January 2022 and June 2023 were included in this study. The two platforms used were in-house tumor NGS (Illumina NextSeq 550Dx, SureSelectXT library kit, and datasets from 1000 Genomes, ESP6500, ExAC, and ClinVar) and GreenPlan homologous recombination deficiency (HRD) test (Illumina NextSeq 550Dx, customized Twist Bioscience library kit, and datasets from COSMIC and OncoKB). The results of somatic mutations in BRCA1 and BRCA2 were compared between the two platforms. Of the 118 patients, 11.9% (n = 14) exhibited a discordant interpretation of BRCA1 or BRCA2 between the two platforms. Eleven patients (9.3%) exhibited negative results in the in-house platform but positive results (eight seven as PV of BRCA1, one as PV of BRCA2, one as LPV of BRCA1, and two as LPV of BRCA2) in the GreenPlan HRD test, while three patients (2.6%) had positive BRCA pathogenic variants (two as PV of BRCA1 [c.3340G > T, c.5152 + 3 A > C], one as LPV of BRCA2 [c.8174G > T], and one as LPV of BRCA1 [c.5017_5019delCAC]) in the in-house platform but a negative result in the GreenPlan HRD test. The discordance rate of somatic BRCA1 or BRCA2 mutations from different platforms was approximately 12%. In the case of the strong implication of BRCA PV/LPV with a negative result with one genetic test, different platforms could be considered in limited cases. Careful interpretation and further studies for the cross-validation of gene analysis platforms are needed.

Nucleation occurs widely in materials synthesis and natural environments. However, in the nucleation rate equation, values for the apparent activation energy (Ea) and the pre-exponential kinetic factor (A) are thus far unknown because real-time nanoscale observations are difficult to perform. Here we experimentally determine Ea and A using heterogeneous calcium carbonate nucleation on quartz as a model system. Nucleation rates are measured with in situ grazing incidence small-angle X-ray scattering and ex situ atomic force microscopy, and the experiments are conducted with a fixed supersaturation of IAP/Ksp(calc) = 101.65 at 12, 25, and 31 °C. Ea is calculated as 45 ± 7 kJ mol−1, and A is 1012.0 ± 1.1 nuclei μm−2 min−1, or 102.9 ± 1.3 mol m−2 min−1. Increasing the temperature shortens the induction time, but does not change nucleus sizes. These parameter values are critical for predicting and controlling the nucleation of materials. Nucleation is a ubiquitous process, but key kinetic parameters governing the rate of nucleation can be difficult to measure. Here a combination of in situ GISAXS and ex situ AFM measurements allows experimental determination of the activation energy and pre-exponential kinetic factor for heterogeneous CaCO3 nucleation on quartz. [ABSTRACT FROM AUTHOR]

Many challenges related to carbon-dioxide ( CO 2 ) sequestration in subsurface rock are linked to the injection of fluids through induced or existing fracture networks and how these fluids are altered through geochemical interactions. Here, we demonstrate that fluid mixing and carbonate mineral distributions in fractures are controlled by gravity-driven chemical dynamics. Using optical imaging and numerical simulations, we show that a density contrast between two miscible fluids causes the formation of a low-density fluid runlet that increases in areal extent as the fracture inclination decreases from 90 ∘ (vertical fracture plane) to 30 ∘ . The runlet is sustained over time and the stability of the runlet is controlled by the gravity-driven formation of 3D vortices that arise in a laminar flow regime. When homogeneous precipitation was induced, calcium carbonate covered the entire surface for horizontal fractures (0 ∘ ). However, for fracture inclinations greater than 10 ∘ , the runlet formation limited the areal extent of the precipitation to less than 15% of the fracture surface. These insights suggest that the ability to sequester CO 2 through mineralization along fractures will depend on the fracture orientation relative to gravity, with horizontal fractures more likely to seal uniformly. [ABSTRACT FROM AUTHOR]