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Surface meltwater on ice shelves can exist as slush, it can pond in lakes or crevasses, or it can flow in surface streams and rivers. The collapse of the Larsen B Ice Shelf in 2002 has been attributed to the sudden drainage of ∼3000 surface lakes and has highlighted the potential for surface water to cause ice-shelf instability. Surface meltwater systems have been identified across numerous Antarctic ice shelves, although the extent to which these systems impact ice-shelf instability is poorly constrained. To better understand the role of surface meltwater systems on ice shelves, it is important to track their seasonal development, monitoring the fluctuations in surface water volume and the transfer of water across ice-shelf surfaces. Here, we use Landsat 8 and Sentinel-2 imagery to track surface meltwater across the Nivlisen Ice Shelf in the 2016–2017 melt season. We develop the Fully Automated Supraglacial-Water Tracking algorithm for Ice Shelves (FASTISh) and use it to identify and track the development of 1598 water bodies, which we classify as either circular or linear. The total volume of surface meltwater peaks on 26 January 2017 at 5.5×107 m3. At this time, 63 % of the total volume is held within two linear surface meltwater systems, which are up to 27 km long, are orientated along the ice shelf's north–south axis, and follow the surface slope. Over the course of the melt season, they appear to migrate away from the grounding line, while growing in size and enveloping smaller water bodies. This suggests there is large-scale lateral water transfer through the surface meltwater system and the firn pack towards the ice-shelf front during the summer.

Surface runoff at the margin of the Greenland Ice Sheet (GrIS) drains to the ice-sheet bed, leading to enhanced summer ice flow. Ice velocities show a pattern of early summer acceleration followed by mid-summer deceleration due to evolution of the subglacial hydrology system in response to meltwater forcing. Modelling the integrated hydrological–ice dynamics system to reproduce measured velocities at the ice margin remains a key challenge for validating the present understanding of the system and constraining the impact of increasing surface runoff rates on dynamic ice mass loss from the GrIS. Here we show that a multi-component model incorporating supraglacial, subglacial, and ice dynamic components applied to a land-terminating catchment in western Greenland produces modelled velocities which are in reasonable agreement with those observed in GPS records for three melt seasons of varying melt intensities. This provides numerical support for the hypothesis that the subglacial system develops analogously to alpine glaciers and supports recent model formulations capturing the transition between distributed and channelized states. The model shows the growth of efficient conduit-based drainage up-glacier from the ice sheet margin, which develops more extensively, and further inland, as melt intensity increases. This suggests current trends of decadal-timescale slowdown of ice velocities in the ablation zone may continue in the near future. The model results also show a strong scaling between average summer velocities and melt season intensity, particularly in the upper ablation area. Assuming winter velocities are not impacted by channelization, our model suggests an upper bound of a 25 % increase in annual surface velocities as surface melt increases to 4 × present levels.

A key challenge in modelling coupled ice-flow–subglacial hydrology is initializing the state and parameters of the system. We address this problem by presenting a workflow for initializing these values at the start of a summer melt season. The workflow depends on running a subglacial hydrology model for the winter season, when the system is not forced by meltwater inputs, and ice velocities can be assumed constant. Key parameters of the winter run of the subglacial hydrology model are determined from an initial inversion for basal drag using a linear sliding law. The state of the subglacial hydrology model at the end of winter is incorporated into an inversion of basal drag using a non-linear sliding law which is a function of water pressure. We demonstrate this procedure in the Russell Glacier area and compare the output of the linear sliding law with two non-linear sliding laws. Additionally, we compare the modelled winter hydrological state to radar observations and find that it is in line with summer rather than winter observations.

The ethanol extract of the kernel of the endemic plant Moringa stenopetala after silica gel column chromatography led to the isolation of 4-(α-L-rhamnopyranosyloxy)benzyl glucosinolate (1) and sucrose. The oil obtained by Soxhlet extraction with petrol was trans-esterified with BF3-MeOH and analyzed by GC-MS. The results showed the presence of diverse fatty acids namely palmitic (11%), palmitoleic (1.2%), stearic (11%), oleic (63%), linoleic (1.2%), arachidic (6%) and the rare behenic acids (6%). The white glossy seed husk which comprises 25% of the whole seed yielded two compounds namely 4-(σ-L-rhamnosyloxy)benzyl alcohol (2) and allantoin (3). To the best of our knowledge this is the first report of compound 2 as a natural product. Allantoin is reported here for the first time from the genus Moringa.

’n Groenslang (dit is ek) stap skoorvoetend vanaf Heimat in die rigting van die Universiteit, d.w.s. die hoofgebou en enigste gebou. Sy pad gaan tussen vier, nogal nie te bouvallige, lang plat sinkgeboue deur.

Introduction: Monitoring changes in symptoms over time during long-term nocturnal home non-invasive ventilation (NIV) using patient-reported outcome measures is crucial. This study aimed to identify factors associated with changes in the S3-NIV total score, its two domains ("respiratory symptoms" and "sleep and NIV-related side effects") and individual item responses., Methods: We conducted a retrospective, longitudinal data analysis of a cohort of adults with chronic respiratory failure treated with NIV. Data were obtained from a French homecare provider. Multivariate linear and multinomial ordinal mixed effect models were used to identify factors associated with changes in S3-NIV scores over time., Results: Median follow-up was 2 years for 2135 participants. Each participant completed a median of five S3-NIV questionnaires; totaling 11,359 analyzed questionnaires. Type of respiratory condition, sex, age and time since NIV initiation were associated with change in S3-NIV score over time. NIV adherence was not associated with total S3-NIV score but high adherence was associated with more severe respiratory symptoms and an improvement in sleep and NIV-related side effects during the follow-up. Intensity of pressure support was associated with a lower total S3-NIV score and more side effects. Face masks and supplemental oxygen were associated with a lower S3-NIV total score., Conclusion: Changes in S3-NIV scores over time are associated with the individual's characteristics and NIV settings. Analysis of the two domains and individual items of the S3-NIV could increase understanding of the difficulties experienced by people on NIV., (Copyright © 2024 SEPAR. Published by Elsevier España, S.L.U. All rights reserved.)

Background: Mucociliary clearance is a cornerstone of the management of people with non-cystic fibrosis bronchiectasis (NCFB). SIMEOX, an innovative device, could facilitate autonomous airway clearance, but its use requires specific training. We hypothesised that telecare would be an effective means to train people with NCFB in the handling of device and to monitor and promote device adherence., Objectives: (1) To evaluate frequency of use of the SIMEOX for 10 weeks after telecare training. (2) To assess user satisfaction and clinical efficacy of the SIMEOX+telecare., Methods: Multicentre, prospective, pilot study in adults with NCFB. A SIMEOX was provided to each participant at inclusion. Physiotherapists performed telecare sessions the first 2 weeks (3-5 sessions) for device training and every 10 days to reinforce motivation and provide technical support., Results: 22 individuals were included, 21 analysed (38% male; mean±SD age 53±18 years; Bronchiectasis Severity Index 6.6±3.5). Fourteen participants (66.7%; 95% CI 43.1% to 84.5%) performed ≥3 SIMEOX sessions/week (self-reported adherence, primary outcome). Median (Q1; Q3) number of self-reported sessions/week for the whole group was 3.7 (1.8; 5.7). Adherence including web registration was 80.9%. At week 12, participant satisfaction rating was 9.0 (7.9; 10.0) on a 10-point visual analogue scale; respiratory function did not change but quality of life improved (COPD Assessment Test score -4.7, 95% CI -7.7 to -1.6, p=0.023; St Georges Respiratory Questionnaire -5.8, 95% CI -10.8 to -0.9, p=0.005)., Conclusion: Adherence to and satisfaction with the SIMEOX airway clearance device supported by telecare were high in people with NCFB. The clinical efficacy needs to be confirmed in a randomised controlled trial., Trial Registration Number: NCT04742270., Competing Interests: Competing interests: J-CB, EJ, MM-E, RA and NA are salaried by the group AGIR à dom-ICADOM (French Homecare provider and CRO); LM is salaried by Physio-Assist. SJ, Hugues Gauchez, R Hamidfar have received personal fees from Physio-assist., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Introduction: Obstructive sleep apnoea syndrome (OSAS) is one of the most common chronic diseases. It may be associated with symptoms of excessive daytime sleepiness and neurocognitive and cardiovascular complications. First line therapy for OSAS involves home continuous positive airway pressure (CPAP), however, nearly half of patients do not adhere with this treatment over the long term. Cognitive-behavioural interventions that include health professionals and patient and public involvement are increasingly advocated in the fields of education and research. We hypothesise that a peer-driven intervention could help patients with OSAS to resume CPAP use after discontinuation., Methods and Analysis: We have designed a prospective, multicentre randomised, controlled trial that will be coconducted by health professionals, a home provider of CPAP and patients as experts or peers or participants. The primary aim is to evaluate the impact of a 6-month, peer-driven intervention to promote the resumption of CPAP after discontinuation. We anticipate that 20% of patients in the intervention group will reuse CPAP as compared with 6% in control group, thus, 104 patients must be included in each group. The secondary aims are (1) to evaluate the impact of the peer-driven intervention on adherence to CPAP compared with the control group (mean adherence and percentage of nights with at least 4 hours' use/night for 70% of nights); (2) to determine factors associated with resumption of CPAP; (3) to assess patient satisfaction with the peer-driven intervention at 6 months; (4) to evaluate the feasibility and the execution of the peer-driven intervention and peer satisfaction. Adult outpatients with an established diagnosis of severe OSA (Apnoea-Hypopnoea Index >30 events/hour) that have stopped using CPAP within 4-12 months after initiation will be recruited. The peers who will perform the intervention will be patients with OSAS treated with CPAP with good adherence (at least 4 hours/night, 70% of nights) and trained in motivational enhancement and cognitive-behavioural therapies. Trained peers will conduct three interviews within 6 months with participants., Ethics and Dissemination: Ethical approval has been obtained from the French Regional Ethics Committee CPP Ouest II-Angers, (IRB 21.02.25.68606 (2021/2025)). All participants will sign written informed consent. The results will be presented at conferences and published in peer-reviewed journals as well as public media., Trial Registration Number: NCT04538274., Competing Interests: Competing interests: RM is a recipient of a grant from Agir pour les Maladies Chroniques, http://fonds-apmc.org/. CD, NA, JCB are employees of AGIR à dom. CP and JLP received grants from Agir pour les Maladies Chroniques, http://fonds-apmc.org/., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY. Published by BMJ.)

Diagnosis of sleep apnea (SA) using simple tools has the potential to improve the efficacy of cardiac implants in the prevention of cardiac arrhythmias. The aim of the present study was to validate a transthoracic impedance sensor for SA diagnosis in patients with cardiac implants. We compared the apnea-hypopnea index (AHI) obtained from polysomnography (AHI PSG ) with the AHI obtained from autoscoring algorithms of the ApneaScan implantable impedance respiration sensor (AHI AS ) three months after implantation of cardioverter-defibrillator (ICD) or cardiac resynchronization therapy-defibrillator (CRT-D) devices. Twenty-five patients with indications for implantation of ICD or CRT-D (INCEPTA; Boston Scientific) (24 men, 59.9 ± 14.4 years; LVEF 30.3 ± 6.4%; body mass index 25.9 ± 4.2 kg/m²) were included. Mean AHI- PSG was 21.9 ± 19.1 events/hr. A significant correlation was found between AHI PSG and AHI AS especially for the most severe SA (Spearman correlation: 0.71, p < 0.001). Intraclass Correlation Coefficient (was in the expected range: 0.67, 95% CI: 0.39-0.84. The mean bias was 5.4 events per hour (mean AHI: 23.3 ± 14.6 versus 29.7 ± 13.7 for AHI- PSG and AHI- AS, respectively). An optimal cutoff value for the AHI AS at 30 events/h was obtained from the Receiver Operator Characteristic (ROC) curve analysis, which yielded a sensitivity of 100%, a specificity of 80%, PPV = 67%, NPV = 100%. Using an advanced algorithm for autoscoring of transthoracic impedance included in ICDs is reliable to identify SA and has the potential to improve the management of patients with cardiac implants.

Purpose: This study investigates the effect of increased ocular perfusion pressure (OPP) on optic nerve head (ONH) hemodynamics., Methods: In 21 healthy subjects, the increase in arterial blood pressure (BP), measured continuously using a pneumatic transcutaneous sensor, was produced by isometric exercise consisting of 2 minutes of hand-gripping. ONH blood flow parameters-namely the velocity (Vel), number (Vol), and flux (F) of red blood cells-were measured using the laser Doppler flowmeter (LDF)., Results: In those 14 healthy subjects who exhibited a similar increase in BP to handgrip superior to 30% of baseline BP, group average increases of BP and OPP amounted to 34% ± 3% (SEM) and 43% ± 3%, respectively. The increase in F of 19% ± 8%, resulting from an increase in Vel (17% ± 7%) and Vol (6% ± 7%), was significantly less than predicted for a passive autoregulatory response, as revealed also by the increase in vascular resistance (R = OPP/F). Spearman test of linear correlations between F and time during handgrip led to the identification of one group of eight subjects (with a stable F) and one group of six subjects (with an increase in F). A closed-loop gain (G) of the regulatory process, defined as G = 1 - {(F - Fbl)/Fbl}/{(OPP - OPPbl)/OPPbl}, was found to be rather independent from the OPP, with an average value 0.7 ± 0.07. G was 0.83 ± 0.06 for the group of eight subjects with stable F and 0.3 ± 0.15 for the group of six subjects with F increasing with the OPP., Conclusions: The continuous recording of both BP and LDFs represents a novel and more precise approach to the characterization of ONH hemodynamics during isometric exercise, especially useful in the future for patients with ocular diseases. The efficiency of the ONH blood flow autoregulation appears to vary significantly between healthy subjects. (ClinicalTrials.gov number, NCT00874913.).

Background: Obesity hypoventilation syndrome (OHS) is associated with increased cardiovascular morbidity. What moderate chronic hypoventilation adds to obesity on systemic inflammation and endothelial dysfunction remains unknown., Question: To compare inflammatory status and endothelial function in OHS versus eucapnic obese patients., Methodology: 14 OHS and 39 eucapnic obese patients matched for BMI and age were compared. Diurnal blood gazes, overnight polysomnography and endothelial function, measured by reactive hyperemia peripheral arterial tonometry (RH-PAT), were assessed. Inflammatory (Leptin, RANTES, MCP-1, IL-6, IL-8, TNFalpha, Resistin) and anti-inflammatory (adiponectin, IL-1Ra) cytokines were measured by multiplex beads immunoassays., Principal Findings: OHS exhibited a higher PaCO(2), a lower forced vital capacity (FVC) and tended to have a lower PaO(2) than eucapnic obese patients. (HS)-CRP, RANTES levels and glycated haemoglobin (HbA1c) were significantly increased in OHS (respectively 11.1+/-10.9 vs. 5.7+/-5.5 mg x l(-1) for (HS)-CRP, 55.9+/-55.3 vs 23.3+/-15.8 ng/ml for RANTES and 7.3+/-4.3 vs 6.1+/-1.7 for HbA1c). Serum adiponectin was reduced in OHS (7606+/-2977 vs 13,660+/-7854 ng/ml). Endothelial function was significantly more impaired in OHS (RH-PAT index: 0.22+/-0.06 vs 0.51+/-0.11)., Conclusions: Compared to eucapnic obesity, OHS is associated with a specific increase in the pro-atherosclerotic RANTES chemokine, a decrease in the anti-inflammatory adipokine adiponectin and impaired endothelial function. These three conditions are known to be strongly associated with an increased cardiovascular risk., Trial Registration: ClinicalTrials.gov NCT00603096.