Sediments surrounding hydrothermal vents are important transition spaces between hydrothermal and pelagic environments. These sediments accumulate through diverse processes that include water column ...plume fallout, volcanic ash deposition, and mass wasting of hydrothermal chimneys and mounds superimposed upon background sedimentation which may originate from pelagic, terrestrial, and volcanic sources. In addition to being a sink for elements discharged from hydrothermal vents, elements may also be scavenged from seawater onto oxidized hydrothermal material. Preservation of these hydrothermal sediments may occur depending on the extent of oxidative and/or reductive dissolution processes after burial. Sediments remaining adjacent to active venting may also be hydrothermally altered after emplacement. To better understand these processes, here we evaluate sediment push cores collected from the Loki's Castle vent field at the intersection of the slow‐ultraslow spreading Mohns and Knipovich mid‐ocean ridges. All samples were collected within ∼225 m of current high‐temperature (299–316°C) “black smoker” fluid discharge. These sediment cores are highly heterogeneous and lack stratigraphic correlation, even for samples taken within meters of each other. Most sediment cores are dominated by either pelagic sediments or mass wasted hydrothermal material, with hydrothermal plume fallout contributing a low proportion of material, and only a single volcanic ash layer occurring in one of the 13 cores. Dominant hydrothermal minerals found include talc, goethite, pyrite, pyrrhotite, and sphalerite. We find that even after several thousand years, most mass wasted hydrothermal material remains minimally altered, with sedimentation rates indistinguishable from background rates within several hundred meters of the hydrothermal vent source.
Plain Language Summary
Sediments on the ocean floor are often used to better understand the past, as going deeper into a sediment column corresponds to going back in time. At hydrothermal vent sites, sediments may accumulate rapidly due to mineral formation and precipitation from “black smoke,” potentially recording past hydrothermal activity and the movement of rock or sediment downslope as a result of gravity. Here, we examine sediment push cores collected by a remotely operated vehicle from Loki's Castle vent field and found sediments dominated by hydrothermal material that transitioned into sediments formed by background oceanic processes over short distances of only a few hundred meters. We also found that talc, a magnesium silicate mineral, was one of the major hydrothermal minerals, which is surprising as sulfide, sulfate, and oxide minerals are much more commonly documented as major hydrothermal minerals.
Key Points
At Loki's Castle, hydrothermal sediment accumulation is dominated by mass wasting and is highly local to the high temperature vent sources
Sediment core organic carbon content is low, and observed post‐burial alteration is minimal in most cores
Goethite, talc, and pyrrhotite are the predominant hydrothermal minerals occurring in sediments from the Loki's Castle vent field
AbstractQuestionWhat health information needs are perceived by people with low back pain?DesignSystematic review of publications examining perceived health information needs related to low back pain ...identified through Medline, EMBASE, CINAHL and PsycINFO (1990 to 2018).ParticipantsAdults with low back pain of any duration.Data extraction and analysisTwo reviewers independently extracted descriptive data regarding study design and methodology, and assessed risk of bias. Aggregated findings of the perceived needs of people with low back pain regarding health information were meta-synthesised.ResultsForty-one studies (34 qualitative, four quantitative and three mixed-methods) were identified. Two major areas of perceived health information needs for low back pain emerged. The first major area was needs related to information content: general information related to low back pain, its cause and underlying pathology; strong desire for diagnosis and imaging; prognosis, future disability and effect on work capacity; precipitants and management of flares; general management approaches; self-management strategies; prevention; and support services. The second major area of needs related to how the information was delivered. People with low back pain wanted clear, consistent information delivered in suitable tone and understandable language.ConclusionAvailable data suggest that the information needs of people with low back pain are centred around their desire for a diagnosis, potentially contributing to expectations for and overuse of imaging. People with low back pain expressed a strong desire for clear, consistent and personalised information on prognosis, treatment options and self-management strategies, related to healthcare and occupational issues. To correct unhelpful beliefs and optimise delivery of evidence-based therapy, patient and healthcare professional education (potentially by an integrated public health approach) may be warranted.
Bronchiolitis obliterans syndrome (BOS) is a devastating pulmonary complication affecting long-term survivors of allogeneic hematopoietic cell transplantation. Treatment of BOS with prolonged courses ...of high dose corticosteroids is often associated with significant morbidity. Reducing the exposure to corticosteroids may reduce treatment-related morbidity. Our institution has recently begun to treat patients with emerging therapies in an effort to diminish corticosteroid exposure. We retrospectively reviewed the 6-month corticosteroid exposure, lung function and failure rates in eight patients with newly diagnosed BOS who were treated with a combination of fluticasone, azithromycin and montelukast (FAM) and a rapid corticosteroid taper. These patients were compared with 14 matched historical patients who received high-dose corticosteroids, followed by a standard taper. The median 6-month prednisone exposure in FAM-treated patients was 1819 mg (0-4036 mg) compared with 7163 mg (6551-7829 mg) in the control group (P=0.002). The median forced expiratory volume in 1 s (FEV(1)) change in FAM-treated patients was 2% (-3 to 4% compared with 1% (-4 to 5%) in the control group (P=1.0). Prednisone exposure in FAM patients was one quarter that of a retrospective-matched group of patients, with minimal change in median FEV(1), suggesting that BOS may be spared of the morbidities associated with long-term corticosteroid use by using alternative agents with less side effects.
Implantable-cardioverter defibrillators (ICD) detect and terminate life-threatening ventricular tachyarrhythmia with electric shocks after they occur. This puts patients at risk if they are driving ...or in a situation where they can fall. ICD's shocks are also very painful and affect a patient's quality of life. It would be ideal if ICDs can accurately predict the occurrence of ventricular tachyarrhythmia and then issue a warning or provide preventive therapy. Our study explores the use of ICD data to automatically predict ventricular arrhythmia using heart rate variability (HRV). A 5 minute and a 10 second warning system are both developed and compared. The participants for this study consist of 788 patients who were enrolled in the ICD arm of the Sudden Cardiac Death-Heart Failure Trial (SCD-HeFT). Two groups of patient rhythms, regular heart rhythms and pre-ventricular-tachyarrhythmic rhythms, are analyzed and different HRV features are extracted. Machine learning algorithms, including random forests (RF) and support vector machines (SVM), are trained on these features to classify the two groups of rhythms in a subset of the data comprising the training set. These algorithms are then used to classify rhythms in a separate test set. This performance is quantified by the area under the curve (AUC) of the ROC curve. Both RF and SVM methods achieve a mean AUC of 0.81 for 5-minute prediction and mean AUC of 0.87-0.88 for 10-second prediction; an AUC over 0.8 typically warrants further clinical investigation. Our work shows that moderate classification accuracy can be achieved to predict ventricular tachyarrhythmia with machine learning algorithms using HRV features from ICD data. These results provide a realistic view of the practical challenges facing implementation of machine learning algorithms to predict ventricular tachyarrhythmia using HRV data, motivating continued research on improved algorithms and additional features with higher predictive power.
Innovative solutions are required to provide mental health support at scale in low-resource humanitarian contexts. We aimed to assess the effectiveness of a facilitator-guided, group-based, self-help ...intervention (Self-Help Plus) to reduce psychological distress in female refugees.
We did a cluster randomised trial in rural refugee settlements in northern Uganda. Participants were female South Sudanese refugees with at least moderate levels of psychological distress (cutoff ≥5 on the Kessler 6). The intervention comprised access to usual care and five 2-h audio-recorded stress-management workshops (20–30 refugees) led by briefly trained lay facilitators, accompanied by an illustrated self-help book. Villages were randomly assigned to either intervention (Self-Help Plus or enhanced usual care) on a 1:1 basis. Within 14 villages, randomly selected households were approached. Screening of women in households continued until 20–30 eligible participants were identified per site. The primary outcome was individual psychological distress, assessed using the Kessler 6 symptom checklist 1 week before, 1 week after, and 3 months after intervention, in the intention-to-treat population. All outcomes were measured at the individual (rather than cluster) level. Secondary outcomes included personally identified problems, post-traumatic stress, depression symptoms, feelings of anger, social interactions with other ethnic groups, functional impairment, and subjective wellbeing. Assessors were masked to allocation. This trial was prospectively registered at ISRCTN, number 50148022.
Of 694 eligible participants (331 Self-Help Plus, 363 enhanced usual care), 613 (88%) completed all assessments. Compared with controls, we found stronger improvements for Self-Help Plus on psychological distress 3 months post intervention (β −1·20, 95% CI −2·33 to −0·08; p=0·04; d −0·26). We also found larger improvements for Self-Help Plus 3 months post-intervention for five of eight secondary outcomes (effect size range −0·30 to −0·36). Refugees with different trauma exposure, length of time in settlements, and initial psychological distress benefited similarly. With regard to safety considerations, the independent data safety management board responded to six adverse events, and none were evaluated to be concerns in response to the intervention.
Self-Help Plus is an innovative, facilitator-guided, group-based self-help intervention that can be rapidly deployed to large numbers of participants, and resulted in meaningful reductions in psychological distress at 3 months among South Sudanese female refugees.
Research for Health in Humanitarian Crises (R2HC) Programme.
This study aimed to investigate the role of endothelin-1 (ET-1), originally known as the potent vasoconstrictor, and its receptors in chondrocyte senescence and osteoarthritis (OA) development.
...Temporal changes of ET-1 and its receptors with OA development were characterized in a posttraumatic OA (PTOA) mouse model at time zero, 1-month and 4-month after surgical induction via destabilization of medial meniscus (DMM). A transgenic ET-1 overexpression (TET-1) mouse model was deployed to assess the impact of upregulated ET-1 on chondrocyte senescence and cartilage degradation. Effects of endothelin receptor blockade on chondrocyte senescence and OA development were further examined both in vitro and in vivo.
Local expression of ET-1 in subchondral bone and synovium upregulated after DMM with an increase of plasma ET-1 level from 3.18 ± 0.21 pg/ml at time zero to 6.47 ± 0.34 pg/ml at 4-month post-surgery. Meanwhile, endothelin type B receptor (ETBR) (53.31 ± 2.42% to 83.8 ± 2.65%) and p16INK4a (10.91 ± 1.07% to 28.2 ± 1.0%) positve chondrocytes accumulated in articular cartilage since 1-month prior to cartilage loss at 4-month post-surgery. Overexpressed ET-1 promoted p16INK4a-positive senescent chondrocytes accumulation and cartilage degradation in TET-1 mice. Selective blockade of ETBR, but not ETAR, lowered the expression of p16INK4a in ET-1 or H2O2-induced chondrocyte senescence model, and mitigated the severity of murine PTOA. Intriguingly, reactive oxygen species (ROS) scavenger, Vitamin C, could rescue ET-1-induced chondrocyte senescence in vitro associated with restoration of mitochondrial dynamics.
ET-1 could induce chondrocytes senescence and cartilage damages via ETBR in PTOA.
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Limited data exist on antibody responses to mixed vaccination strategies that involve inactivated coronavirus disease 2019 (COVID-19) vaccines, particularly in the context of emerging variants.
We ...conducted an open-label trial of a third vaccine dose of a messenger RNA (mRNA) vaccine (BNT162b2, Fosun Pharma/BioNTech) in adults aged ≥30 years who had previously received 2 doses of inactivated COVID-19 vaccine. We collected blood samples before administering the third dose and 28 days later and tested for antibodies to the ancestral virus using a binding assay (enzyme-linked immunosorbent assay ELISA), a surrogate virus neutralization test (sVNT), and a live virus plaque reduction neutralization test (PRNT). We also tested for antibodies against the Omicron variant using live-virus PRNT.
In 315 participants, a third dose of BNT162b2 substantially increased antibody titers on each assay. Mean ELISA levels increased from an optical density of 0.3 to 2.2 (P < .001), and mean sVNT levels increased from an inhibition of 17% to 96% (P < .001). In a random subset of 20 participants, the geometric mean PRNT50 titers rose substantially, by 45-fold from day 0 to day 28 against the ancestral virus (P < .001) and by 11-fold against the Omicron variant (P < .001). In daily monitoring, post-vaccination reactions subsided within 7 days for more than 99% of participants.
A third dose of COVID-19 vaccine with an mRNA vaccine substantially improved antibody levels against the ancestral virus and the Omicron variant with a well-tolerated safety profile in adults who had received 2 doses of inactivated vaccine 6 months earlier.
NCT05057182.
The large-scale production and ecotoxicity of urea make its removal from wastewater a health and environmental challenge. Whereas the industrial removal of urea relies on hydrolysis at elevated ...temperatures and high pressure, nature solves the urea disposal problem with the enzyme urease under ambient conditions. We show that CeO2−x nanorods (NRs) act as the first and efficient green urease mimic that catalyzes the hydrolysis of urea under ambient conditions with an activity (kcat = 9.58 × 101 s−1) about one order of magnitude lower than that of the native jack bean urease. The surface properties of CeO2−x NRs were probed by varying the Ce4+/Ce3+ ratio through La doping. Although La substitution increased the number of surface defects, the reduced number of Ce4+ sites with higher Lewis acidity led to a slight decrease of their catalytic activity. CeO2−x NRs are stable against pH changes and even to the presence of transition metal ions like Cu2+, one of the strongest urease inhibitors. The low costs and environmental compatibility make CeO2−x NRs a green urease substitute that may be applied in polymer membranes for water processing or filters for the waste water reclamation. The biomimicry approach allows the application of CeO2−x NRs as functional enzyme mimics where the use of native or recombinant enzyme is hampered because of its costs or operational stability.
Developmental and epileptic encephalopathies (DEEs) are severe clinical conditions characterized by stagnation or decline of cognitive and behavioral abilities preceded, accompanied or followed by ...seizures. Because DEEs are clinically and genetically heterogeneous, next-generation sequencing, especially exome sequencing (ES), is becoming a first-tier strategy to identify the molecular etiologies of these disorders.
We combined ES analysis and international data sharing.
We identified 11 unrelated individuals with DEE and de novo heterozygous truncating variants in the interferon regulatory factor 2-binding protein-like gene (IRF2BPL). The 11 individuals allowed for delineation of a consistent neurodevelopmental disorder characterized by mostly normal initial psychomotor development followed by severe global neurological regression and epilepsy with nonspecific electroencephalogram (EEG) abnormalities and variable central nervous system (CNS) anomalies. IRF2BPL, also known as enhanced at puberty protein 1 (EAP1), encodes a transcriptional regulator containing a C-terminal RING-finger domain common to E3 ubiquitin ligases. This domain is required for its repressive and transactivating transcriptional properties. The variants identified are expected to encode a protein lacking the C-terminal RING-finger domain.
These data support the causative role of truncating IRF2BPL variants in pediatric neurodegeneration and expand the spectrum of transcriptional regulators identified as molecular factors implicated in genetic developmental and epileptic encephalopathies.
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