Search Results (36)

Background/Objectives: The Pleth Variability Index (PVI) is a non-invasive parameter used to guide fluid management by reflecting respiratory-induced variations in the plethysmographic waveform. While PVI’s reliability in various positions has been studied, data on its behavior in geriatric patients undergoing transurethral resection of the prostate (TUR-P) in the lithotomy position remain limited. This study aimed to evaluate the effect of the lithotomy position on PVI in geriatric versus non-geriatric patients under spinal anesthesia. Methods: This prospective observational study included 90 patients undergoing elective TUR-P in the lithotomy position under spinal anesthesia. Patients were divided into geriatric (≥65 years, n = 48) and non-geriatric (<65 years, n = 42) groups. PVI and Perfusion Index (PI) were recorded at baseline, in the supine position, and in the lithotomy position. Fluid and vasopressor requirements, along with hemodynamic parameters, were also analyzed. Results: PVI values at the 5th minute in the lithotomy position were significantly higher in the geriatric group compared to the non-geriatric group (p = 0.019). No significant differences were observed in PI values or intraoperative hypotension rates between the groups. Neurological comorbidities were more prevalent in the geriatric group (p = 0.025). Conclusions: PVI appears to be a more sensitive indicator of fluid responsiveness in elderly patients under spinal anesthesia in the lithotomy position. Its age-dependent variability suggests clinical utility in guiding fluid management in geriatric populations, while the stable hypotension rates support the effectiveness of PVI-guided goal-directed therapy. Full article

Background/Objectives: Pulmonary vein isolation (PVI) is the standard treatment for atrial fibrillation (AF), but medium-term success rates remain suboptimal. Non-pulmonary vein triggers, particularly from the superior vena cava (SVC), contribute to AF recurrence. Empirical SVC isolation (SVCi) in addition to standard PVI may improve outcomes. This study evaluated the acute procedural efficacy and safety of PVI with adjunctive SVCi versus PVI alone in patients with paroxysmal AF (PAF). Methods: In this randomized, controlled, single-center study, 149 patients with PAF were assigned to either standard PVI (n = 74) or PVI with adjunctive empirical SVCi (n = 75) using a fourth-generation CB. Primary endpoints were acute procedural success and the incidence of procedure-related complications, particularly phrenic nerve injury (PNI) and sinus node dysfunction. Results: Acute PVI was achieved in all patients; SVCi was successful in 84.9% of the PVI + SVCi group. Major complication rates were low and comparable between groups (0% vs. 2.6%, p = 0.157). However, the overall complication rate was significantly higher in the PVI + SVCi group (50.6% vs. 6.8%, p < 0.001), driven primarily by transient or impending right PNI (38.6% vs. 6.8%, p < 0.001) and sinus node dysfunction. All PNI events resolved before the end of the procedure. Conclusions: Empirical SVCi using a fourth-generation CB is feasible and generally safe, but carries a higher risk of transient PNI and reversible sinus node dysfunction. Therefore, CB SVCi should be approached with caution. Further studies are needed to evaluate long-term outcomes and assess whether the potential benefits outweigh these procedural risks. Full article

This study explores rhythm metrics as a sociolinguistic marker in Philippine English (PhE), addressing gaps in understanding rhythmic variation in Southeast Asian Englishes. It aims to uncover how rhythmic patterns reflect sociolectal identities within a multilingual context. Using acoustic data from 30 participants in Manila, rhythm metrics (%V, ΔV, ΔC, nPVI, and rPVI) were analyzed to examine rhythmic tendencies. The findings reveal distinct patterns: PhE acrolect aligns with stress-timed rhythms of general American English, PhE basilect reflects syllable-timed features similar to Spanish, and PhE mesolect occupies a hybrid position blending elements of both. By emphasizing rhythm as a key identifier of sociolectal variation, this study advances the understanding of linguistic diversity in World Englishes and provides a novel framework for exploring identity in multilingual settings. Full article

Background/Objectives: Pulmonary vein isolation (PVI) is the cornerstone in the treatment of atrial fibrillation (AF). Despite initially successful PVI patients experience recurrence of AF potentially due to reconnection of pulmonary veins (PVs). However, a certain number of patients present with recurrent AF, despite durable PVI. The optimal ablation strategy for these patients has yet to be discerned. The aim of this study was to compare outcomes for different ablation strategies for recurrent AF despite persistent PVI. Methods: All redo procedures for the recurrence of atrial fibrillation from March 2018–May 2023 were analyzed. Only patients with proven durable PVI (entrance/exit block and high density (HD) mapping) who received linear ablation or CFAE (complex fractionated atrial electrogram)/low-voltage area ablation were included. Patients were excluded if re-PVI or ablation of atrial tachycardia (AT) was necessary. In all procedures, a 3D-HD map and radiofrequency ablation (RFA) were performed. The ablation strategy was at the operators’ discretion. Data from a routinely performed 12-month follow-up were obtained. Results: A total of 847 repeat ablation procedures for atrial arrhythmias were analyzed. In 170 (20.1%) procedures, all PVs were still isolated. Of these, 51 (30.0%) patients were excluded due to AT or because they did not receive further left atrial linear ablation or substrate modification. In total, 119 patients were included in the final analysis, and 71 out of 119 patients (59.7%) were male. The majority (89 patients, 74.8%) suffered from persistent AF. In 72 patients (60.5%), LA-scar (voltage < 0.4 mV) was detectable (81.9% persAF). The ablation strategies were either linear ablation (n = 55), a non-linear substrate modification strategy (CFAE ablation/ablation of low-voltage areas, n = 21) or a combination of both (n = 43). In the Kaplan–Meier analysis, none of the ablation strategies showed a significantly superior outcome. After 370.0 ± 144.9 days, 56.0% (48.1% vs. 61.9% vs. 62.8%, p = 0.3) were free from any arrhythmia. 15.4% vs. 9.5% vs. 9.3% developed an AT (p = 0.3). Left atrial dilatation correlated with recurrence of AF. Conclusions: In patients suffering from a recurrence of AF despite durable pulmonary vein isolation, different substrate modification strategies did not show any superiority for one or the other. Despite the necessity of additional ablation beyond PVI, the optimal ablation strategy has yet to be determined to improve the outcome of redo procedures. Full article

Rhythm is fundamental in many physical and biological systems. Rhythm is relevant to a broad range of phenomena across different fields, including animal bioacoustics, speech sciences, and music cognition. As a result, the interest in developing consistent quantitative measures for cross-disciplinary rhythmic analysis is growing. Two quantitative measures that can be directly applied to any temporal structure are the normalized pairwise variability index (nPVI) and rhythm ratios (r_k). The nPVI summarizes the overall isochrony of a sequence, i.e., how regularly spaced a sequence’s events are, as a single value. Meanwhile, r_k quantifies ratios between a sequence’s adjacent intervals and is often used for identifying rhythmic categories. Here, we show that these two rhythmic measures are fundamentally connected: the nPVI is a summary static of the r_k values of a temporal sequence. This result offers a deeper understanding of how these measures are applied. It also opens the door for creating novel, custom measures to quantify rhythmic patterns based on a sequence’s r_k distribution and compare rhythmic patterns across different domains. The explicit connection between nPVI and r_k is one further step towards a common quantitative toolkit for rhythm research across disciplines. Full article

Background: Heart failure (HF) is a progressive condition associated with reduced life expectancy and quality of life. Atrial fibrillation (AF), the most common arrhythmia in HF patients, significantly worsens symptoms and outcomes. The coexistence of HF and AF is linked to higher morbidity and mortality rates, with a bidirectional relationship exacerbating both conditions. The recent evidence has suggested that combining pulmonary vein isolation (PVI) with renal denervation (RDN) may offer a promising strategy for reducing AF burden and enhancing patient outcomes. Methods: This prospective interventional clinical trial aimed to assess the safety and effectiveness of a combined RDN and PVI approach compared to PVI alone. Eighteen patients, aged 18 to 80 years, with paroxysmal or persistent AF and HF (left ventricular ejection fraction [LVEF] < 50%) were enrolled. RDN was performed under general anesthesia using the four-electrode Symplicity Spyral catheter and Symplicity G3 radiofrequency generator (Medtronic). Patients were randomized to the RDN+PVI group (n = 7) or the PVI-only group (n = 11). The groups were similar in age (59 ± 8.4 years vs. 62.5 ± 11.08 years, p = NS) and baseline characteristics, including hypertension, obesity, and impaired left ventricular function (LVEF 35.86% vs. 38.54%, RDN+PVI vs. PVI only; p = NS). Results: Over a mean follow-up of 24 months, one patient died, ten were hospitalized, six underwent repeat PVI, and eight achieved AF freedom. Patients in the RDN+PVI group were significantly more likely to remain AF-free (n = 6 vs. 2; p = 0.0063). The need for repeat ablation was higher in the PVI-only group (54.5% vs. 0%), though this did not reach statistical significance. Hospitalization rates and changes in ejection fraction were similar between groups. Importantly, no procedural complications were observed. Conclusions: Combining RDN with PVI is a safe hybrid approach for AF management in HF patients, showing promising efficacy in reducing AF recurrence. Larger randomized studies are needed to confirm these findings and further explore this novel therapeutic strategy. Full article

Background/Objectives: Pulmonary vein isolation (PVI) using radiofrequency catheter ablation with contact force (CF)-sensing technology has improved long-term outcomes in patients with atrial fibrillation. This prospective randomized study aimed to assess the efficacy and safety of CF-sensing technology for additional left atrial (LA) linear ablation of persistent AF (PerAF). Methods: After PVI, anteromitral (AM) line and roof line ablation were performed using a CF-sensing catheter. Patients were randomly assigned to either the CF-sensing (CFS) group or the CF-blind control (Blind) group. The primary endpoint was atrial arrhythmia recurrence. LA late gadolinium enhancement (LA-LGE) MRI was conducted at baseline and 1-year follow-up for long-term lesion evaluation. Results: A total of 62 patients with drug-refractory PerAF were enrolled (mean age: 58 ± 10 years; 77% male). The success rates of AM and roof line block were 97% and 100% in the CFS group (n = 33) and 93% and 90% in the Blind group (n = 29). The time to achieve block was reduced in the CFS group (AM: 36 ± 22 vs. 48 ± 28 min, p = 0.068; roof: 19 ± 14 vs. 27 ± 15 min, p = 0.031). The maximum CF for safety endpoints was significantly lower in the CFS group (AM: 42 vs. 69 g, p < 0.001; roof: 33 vs. 49 g, p = 0.003). Full linear LA-LGE formation on 1-year MRI did not differ significantly between the groups (AM: 17 vs. 36%; roof; 29 vs. 24%, both p = NS). Kaplan–Meier estimates of AF/AT-free survival after ablation procedures were 63.6% in the CFS group and 58.6% in the Blind group (log-rank p = 0.837). Conclusions: In patients with PerAF, additional LA linear ablation following PVI using CF-sensing technology improved procedural safety and reduced the time needed to achieve conduction block. However, it did not significantly influence clinical outcomes or the formation of permanent full linear lesions. Full article

Background and Objectives: Atrial fibrillation (AF) significantly impacts the quality of life (QoL) of affected individuals. Pulmonary vein isolation (PVI) has emerged as a therapeutic approach to manage AF and improve QoL. This study aimed to assess the QoL in patients with AF undergoing PVI. Methods and Materials: A total of 97 AF patients undergoing PVI (radiofrequency 52.6% (n = 51) and cryoablation 47.4% (n = 46)) at Pauls Stradins Clinical University Hospital were included in this study. QoL was measured using the 36-Item Short-Form Survey (SF-36) before PVI and during a follow-up period of 5.98 ± 1.97 months. Results: This study consisted of 60.8% (n = 59) males, with a mean age of 60.06 ± 11.61 years. A total of 67.0% (n = 65) of patients had paroxysmal AF, and 33.0% (n = 32) had persistent AF. The SF-36 questionnaire revealed major improvements across multiple QoL domains post-PVI, reaching a statistical significance of p < 0.01. Patient factors, such as female gender ([estimate 21.26, 95% CI (7.18, 35.35)], p < 0.01), persistent AF ([estimate 15.49, 95% CI (2.83, 28.15)], p = 0.02), and restored sinus rhythm ([estimate 14.35, 95% CI (1.65, 27.06)], p = 0.03), were associated with significantly improved QoL. Conclusions: PVI in patients with AF positively influences various dimensions of QoL, as evidenced by significant improvement across multiple SF-36 domains. These findings emphasize worsened QoL in patients with AF and the potential benefits of PVI enhancing the overall wellbeing of individuals with AF. Full article

Background: The TactiFlex™ ablation catheter, Sensor Enabled™ (Abbott, Minneapolis, MN, USA), is an open-irrigation radiofrequency (RF) ablation catheter with flexible tip technology. This catheter delivers high-power short-duration (HPSD) RF ablations and has been adopted for atrial fibrillation (AF) ablation. HPSD is well-established not only in pulmonary vein isolation (PVI) but also when targeting extra-pulmonary vein (PV) targets. This study aims to determine the safety, effectiveness, and acute outcomes of PVI plus posterior wall isolation (PWI) in patients with persistent atrial fibrillation (Pe-AF) using HPSD and the TactiFlex™ ablation catheter. Methods: Consecutive patients who underwent the ablation of Pe-AF in our centre between February 2023 and February 2024 were prospectively enrolled in the study. All patients underwent PVI plus PWI using TactiFlex™ and the HPSD strategy. The RF parameters were 50 W on all the PV segments and the roof, and within the posterior wall (PW). Left atrial mapping was performed with the EnSite X mapping system and the high-density multipolar Advisor HD Grid, Sensor Enabled™ mapping catheter. We compared the procedural data using HPSD with TactiFlex™ (n = 52) vs. a historical cohort of patients who underwent PVI plus PWI using HPSD settings and the TactiCath ablation catheter (n = 84). Results: Fifty-two consecutive patients were included in the study. PVI and PWI were achieved in all patients in the TactiFlex™ group. First-pass PVI was achieved in 97.9% of PVs (n = 195/199). PWI was obtained in all cases by delivering extensive RF lesions within the PW. There were no significant differences compared to the TactiCath group: first-pass PVI was achieved in 96.3% of PVs (n = 319/331). Adenosine administration revealed PV reconnection in 5.7% of patients, and two reconnections of the PW were documented. Procedure and RF time were significantly shorter in the TactiFlex™ group compared to the TactiCath group, 73.1 ± 12.6 vs. 98.5 ± 16.3 min, and 11.3 ± 1.5 vs. 23.5 ± 3.6 min, respectively, p < 0.001. The fluoroscopy time was comparable between both groups. No intraprocedural and periprocedural complications related to the ablation catheter were observed. Patients had an implantable loop recorder before discharge. At the 6-month follow-up, 76.8% of patients remained free from atrial arrhythmia, with no significant differences between groups. Conclusions: HPSD PVI plus PWI using the TactiFlex™ ablation catheter is effective and safe. Compared to a control group, the use of TactiFlex™ to perform HPSD PVI plus PWI is associated with a similar effectiveness but with a significantly shorter procedural and RF time. Full article

The aim of this prospective, randomized clinical trial was to evaluate the use of the pleth variability index (PVi) to guide the rate of intraoperative fluid therapy compared to a traditional fixed-fluid-rate approach in ASA 1–2 dogs undergoing surgery. Twenty-seven dogs met the inclusion criteria and were randomly assigned to the conventional fluid management group (CFM, n = 12) or the PVi-guided group (PVi, n = 15). The CFM group received a fixed rate of 5 mL kg⁻¹ h⁻¹ of crystalloid solution, while in the PVi group the rate was continuously adjusted based on the PVi: PVi < 14% = 3 mL kg⁻¹ h⁻¹; 14% ≤ PVi ≥ 20% = 10 mL kg⁻¹ h⁻¹; and PVi > 20% = 15 mL kg⁻¹ h⁻¹. Hypotension (MAP < 65 mmHg) in the CFM was treated with a maximum of two fluid boluses (5 mL kg⁻¹ in 10 min) and in the case of no response, dobutamine (1–3 mcg kg⁻¹ min⁻¹) was administered. In the PVi group, the treatment of hypotension was similar, except when the PVi > 14%, when dobutamine was started directly. Total fluid volume was significantly lower in the PVI group (0.056 ± 0.027 mL kg⁻¹ min⁻¹) compared to the CFM group (0.132 ± 0.115 mL kg⁻¹ min⁻¹), and the incidence of hypotension was lower (p = 0.023) in the PVi group (0%) compared to the CFM group (41%). The mean arterial pressure (MAP) was significantly higher in the PVi group during surgery. Dobutamine was never administered in either group. Preliminary data suggest that the PVi may be considered as a potential target to guide fluid therapy in dogs; larger studies are needed, especially in cases of cardiovascular instability. Full article

Background: Recurrences due to discontinuity in ablation lines are substantial after pulmonary vein isolation (PVI) with radiofrequency ablation for atrial fibrillation. Data are scarce regarding the durability predictors for very high-power short-duration (vHPSD, 90 W/4 s) ablation. Methods: A total of 20 patients were enrolled, who underwent 90 W PVI and a mandatory remapping procedure at 3 months. First-pass isolation (FPI) gaps, and acute pulmonary vein reconnection (PVR) sites were identified at the index procedure; and chronic PVR sites were identified at the repeated procedure. We analyzed parameters of ablation points (n = 1357), and evaluated their roles in predicting a composite endpoint of FPI gaps, acute and chronic PVR. Results: In total, 45 initial ablation points corresponding to gaps in the ablation lines were analyzed. Parameters associated with gaps were interlesion distance (ILD), baseline generator impedance, mean current, total charge, and loss of catheter–tissue contact. The optimal ILD cut-off for predicting gaps was 3.5 mm anteriorly, and 4 mm posteriorly. Conclusions: Biophysical characteristics dependent on generator impedance could affect the efficacy of vHPSD PVI. The use of smaller ILDs is required for effective and durable PVI with vHPSD compared to the consensus targets with lower power ablation, and lower ILDs for anterior applications seem necessary compared to posterior points. Full article

Bitterness from phenylthiocarbamide and 6-n-propylthiouracil (PROP) varies with polymorphisms in the TAS2R38 gene. Three SNPs form two common (AVI, PAV) and four rare haplotypes (AAI, AAV, PVI, and PAI). AVI homozygotes exhibit higher detection thresholds and lower suprathreshold bitterness for PROP compared to PAV homozygotes and heterozygotes, and these differences may influence alcohol and vegetable intake. Within a diplotype, substantial variation in suprathreshold bitterness persists, and some AVI homozygotes report moderate bitterness at high concentrations. A second receptor encoded by a gene containing a functional polymorphism may explain this. Early work has suggested that PROP might activate TAS2R4 in vitro, but later work did not replicate this. Here, we identify three TAS2R4 SNPs that result in three diplotypes—SLN/SLN, FVS/SLN, and FVS/FVS—which make up 25.1%, 44.9%, and 23.9% of our sample. These TAS2R4 haplotypes show minimal linkage disequilibrium with TAS2R38, so we examined the suprathreshold bitterness as a function of both. The participants (n = 243) rated five PROP concentrations in duplicate, interleaved with other stimuli. As expected, the TAS2R38 haplotypes explained ~29% (p < 0.0001) of the variation in the bitterness ratings, with substantial variation within the haplotypes (AVI/AVI, PAV/AVI, and PAV/PAV). Notably, the TAS2R4 diplotypes (independent of the TAS2R38 haplotypes) explained ~7–8% of the variation in the bitterness ratings (p = 0.0001). Given this, we revisited if PROP could activate heterologously expressed TAS2R4 in HEK293T cells, and calcium imaging indicated 3 mM PROP is a weak TAS2R4 agonist. In sum, our data are consistent with the second receptor hypothesis and may explain the recovery of the PROP tasting phenotype in some AVI homozygotes; further, this finding may potentially help explain the conflicting results on the TAS2R38 diplotype and food intake. Full article

Background: Adding electroanatomical left atrial (LA) voltage mapping to cryoballoon ablation (CBA) improves validation of acute pulmonary vein isolation (PVI). Aims: To determine whether the addition of mapping can improve outcome and PVI durability. Methods: One-year outcome and PV reconnection (PVR) rate at first repeat ablation were studied in 400 AF patients in a propensity-matched analysis (age, AF type, CHA₂DS₂-VASc score) between Achieve catheter-guided CBA with additional EnSite LA voltage maps performed pre- and post-CBA (mapping group; N = 200) and CT- and Achieve catheter-guided CBA (control group; N = 200). Clinical success was defined as freedom of documented AF or atrial tachycardia (AT) > 30 s. PV reconnection patterns were characterized in repeat ablations. Results: At 1 year, 77 (19.25%) patients had recurrence of AF/AT, significantly lower than in the mapping group: 21 (10.5%) vs. 56 (28%), p < 0.001. Procedure time was shorter (72.2 ± 25.4 vs. 78.2 ± 29.3 min, p = 0.034) and radiation exposure lower (4465.0 ± 3454.6 Gy.cm² vs. 5940.5 ± 4290.5 Gy.cm², p = 0.037). Use of mapping was protective towards AF/AT recurrence (HR = 0.348; 95% CI 0.210–0.579; p < 0.001), independent of persistent AF type (HR = 1.723; 95% CI 1.034–2.872; p = 0.037), and LA diameter (HR = 1.055; 95% CI 1.015–1.096; p = 0.006). At repeat ablation (N = 90), persistent complete PVI was seen in 14/20 (70.0%) versus 23/70 (32.9%) in the mapping and conventional group, respectively (p = 0.03). Reconnection rate of the right inferior PV was lower with mapping (10.0% vs. 34,3%, p = 0.035). Conclusions: Adding electroanatomical LA voltage mapping to CBA improves 1-year clinical outcome and lowers both procedure time and radiation exposure. At repeat, use of mapping increases complete persistent PVI mainly by improving PVI durability of the RIPV. Full article

Patients with sickle cell disease (SCD) require repeated blood sampling for hemoglobin (Hb) concentration measurements. The primary aim of this study was to compare non-invasive spectrophotometric hemoglobin (SpHb, g/dL) measurements to those taken via an automated hematology analyzer (Hb, g/dL) in patients with SCD visiting outpatient clinics and to investigate the correlations and agreements between both measurement techniques. Secondarily, we aimed to identify the SpHb cut-off concentration for the diagnosis of anemia and to monitor the effects of the pleth variability index (PVI, %) and perfusion index (PI) on SpHb measurements. The results gained from the examination of one hundred and fifty-eight patients indicated that the SpHb measurements overestimated the lab Hb concentrations, with a mean (SpHb-Hb) bias of 0.82 g/dL (SD 1.29). The SpHb measurements were positively correlated with the Hb measurements (Kendall’s tau correlation (τ), n = 158, τ = 0.68, p < 0.001), with an intra-class correlation (ICC) of 0.67 and a 95% CI from 0.57 to 0.74 (p = 0.000). The SpHb cut-off concentration to diagnose anemia was 11.4 and 11.7 g/dL for males and females, respectively. SpHb sensitivity was low for males and females at 64.4% and 57.1%; however, the specificity was higher at 90.9% and 75%, with positive predictive values (PPVs) of 95.6 and 85.7, respectively. No correlation existed between SpHb measurements and the PVI (%) in contrast with a moderate correlation with the PI (r = 0.049, p = 0.54, and r = 0.36, p < 0.001, respectively). The mean PI was low at 2.52 ± 1.7. In conclusion, the SpHb measurements were consistently higher than the lab Hb concentrations, with a positive correlation. The sensitivity and precision of the SpHb measurements were lower than expected. However, the SpHb specificity and its positive predictive values (PPVs) indicated that it is less likely for a patient with a positive SpHb test result for anemia to be non-anemic. These results will allow SpHb measurement to play a role in excluding the presence of anemia. In light of the low PI values determined, the SpHb measurements were challenging to take and, thus, require further technological improvements. Full article

The interaction of the actinides Pu(III), Am(III), Np(V), Np(VI), and U(VI) with hardened cement paste (HCP) prepared from ordinary Portland cement was investigated by batch experiments in a diluted caprock solution (I = 2.5 M) as a function of the solid-to-liquid (S/L) ratio (0.5–20.0 g L⁻¹) and pH (10–13). Independent of the oxidation state of the actinides, strong sorption was observed with R_d values between 10⁴ and 5 × 10⁵ L kg⁻¹. For the hexavalent actinides U(VI) and Np(VI), a decrease in sorption was observed with increasing pH, which could be due to the formation of the AnO₂(OH)₄²⁻ species. CE-ICP-MS measurements of the supernatant solution from the U(VI) batch sorption experiment at pH ≥ 10 indicate that UO₂(OH)₃⁻ and UO₂(OH)₄²⁻ dominate the speciation. Pu L_III-edge XANES and EXAFS measurements showed oxidation of Pu(III) to Pu(IV) when interacting with HCP. Calcium silicate hydrate (C-S-H) phases effectively immobilize Pu(IV) by incorporating it into the CaO layer. This was observed in a C-S-H sample with C/S = 1.65 and HCP at pH 12.7. Compared to data published in the literature on the retention of actinides on HCP at low ionic strength, the influence of high ionic strength (I = 2.5 M) on the sorption behavior was insignificant. Full article