CFD analysis of hydrodynamic loads on jack-up platforms using buoyancy-modified k-ω SST turbulence model

The offshore jack-up production platform operates in extreme and unpredictable marine environments. Therefore, its structural strength must be designed to withstand harsh conditions, particularly hydrodynamic loads from waves and ocean currents. This study aims to numerically analyze the interaction of marine hydrodynamic forces with a jack-up production platform using OpenFOAM v1606, a Computational Fluid Dynamics (CFD) software. Specifically, the research evaluates a buoyancy-modified k−ω SST turbulence model based on the Standard Gradient Diffusion Hypothesis (SGDH) on a 3D jack-up platform model. The analysis is conducted using a Stokes 5th-order wave model within the waves2Foam toolbox, considering four variations in wave height and period. The results demonstrate that the modified turbulence model provides more accurate predictions. Additionally, they reveal that the forces acting on the platform’s walls are directly proportional to wave height and period, with the highest recorded load reaching 4000 N in Case A, where the wave height and period are 5.4 m and 5.9 s, respectively. Furthermore, it is observed that most of the forces exerted on the platform hull are vertical, primarily due to the negative pressure on the platform’s bottom side

The effect of localized magnetic felds on the spatially controlled crystallization of transition metal complexes

A series of nickel (II) bis-phosphine organometallic complexes along with two pseudo [M7] (M = Ni(II), Zn(II)) metallocalix[6]arene complexes and a dysprosium acetate coordination polymer have each been crystallised in the presence of localized magnetic fields set up using neodymium magnets, using custom made Magnetic Crystallization Towers (MCTs). In all cases, whether the product complex is diamagnetic or paramagnetic, a complex spatial patterning of the crystals occurs based on the orientation of the magnetic field lines. When using magnetic block towers, the crystallization generally occurs adjacent to the magnet face. The effects of nucleation and solution concentration gradients on the crystallization process are also explored. These observations show how the crystallization process is affected by magnetic fields and thus these results have far-reaching effects which most certainly will include crystallization and ion migrations in biology

DNA-binding properties of non-intercalating water-soluble organometallic Ir(III) luminophores

A series of Ir(III) complexes, [Ir(C^N)2(en)]+ (where C^N = 2-phenyl-benzo[d]thiazolyl cyclometalating ligand; en = ethylene diamine), are reported with structural variation via a substituent (H, Me, OMe, Cl, OCF3) at the coordinated phenyl ring. The complexes were soluble in aqueous buffer, with solubility limits correlating inversely with the predicted logP. The complexes display efficient visible absorption at 400-500 nm (e ~ 5000 M-1 cm-1) due to charge-transfer transitions and are triplet emitters in aerated buffer (lem = 529-540 nm; lifetimes up to 0.763 ms; Fem £ 12 %). Each complex was investigated, via computational and biophysical experiments, in the context of DNA binding. According to UV-visible titrations, the cationic complexes bind to DNA with apparent affinities ranging from 6´104 to 5´105 M-1 with apparent binding site sizes between 0.4 and 1.0 base pairs.Isothermal titration calorimetry (ITC) showed that complexes [Ir(L1-3)2(en)]Cl bind to DNA in two types of binding sites, viz. a high affinity (107-108 M-1) binding site with characteristics of major groove binding and a low affinity binding site (105 M-1) with characteristics of non-specific binding to negatively charged DNA, with binding supported by hydrophobic interactions between complexes

Navigating cyber risks on autonomous ships

Maritime Autonomous Surface Ships (MASS) have become a reality in the 21st century, with Yara Birkeland leading the way since 2021. The maritime industry has experienced substantial transformation due to rapid technological advancements, resulting in increased dependence on interconnected digital systems. This technological evolution has introduced novel security vulnerabilities, particularly cyber risks, which are not typically encountered by conventional vessels. Current marine insurance policies and regulatory frameworks inadequately address these cyber risks. Standard insurance clauses generally do not cover cyber incidents, and the existing regulations related to these risks are fragmented and insufficient. Therefore, there is a clear need to establish a tailored approach to address cyber risks associated with MASS.The findings reveal that current forms of these perils fail to explicitly cover cyber incidents, leaving autonomous ships predominantly uninsured against cyber risks. We recommend two main approaches to enhance cyber insurance coverage for MASS: (1) modifying the existing marine and war risk insurance policies to explicitly include coverage for cyber-related incidents; and (2) the development of specialised cyber insurance policies tailored to the unique needs of MASS

Imagery-focused cognitive behavioral therapy techniques for auditory verbal hallucinations in psychosis spectrum disorders: four experimental case series

Background: in psychosis spectrum disorders, maladaptive mental imagery is associated with auditory verbal hallucinations (AVHs). This study evaluates the feasibility, acceptability, and effectiveness of the following 4 imagery techniques in targeting mental imagery and AVHs severity: Imagery Rescripting (ImRs), Promoting positive Imagery de novo (Pos-Im), Metacognitive Imagery techniques (Meta-Im), and playing Tetris.Study design: four replicated single-case series experimental designs were used. Participants were randomized to 1 of the 4 treatment conditions. Primary, we measured the severity of mental imagery and AVHs thrice daily on an 11-point VAS scale during a 2-week baseline, throughout 3 weeks of therapy, and during a 2-week follow-up phase. Randomization tests were used to examine whether daily severity levels of momentary mental imagery and AVHs decreased post-therapy. Secondary, questionnaires assessing the severity of AVHs, mental imagery characteristics, and levels of mood, anxiety, and functioning were administered at baseline, before, and posttreatment.Results: twenty-eight participants completed all treatment sessions. Mental imagery significantly decreased after ImRs (P < .001, d = 1.13) and Pos-Im (P = .039, d = 0.22), with no significant effects observed following Meta-Im or Tetris. AVHs significantly decreased with all treatment conditions, with largest effects for ImRs (P = .001, d = 1.39) and Pos-Im (P < .001, d = 1.99). Secondary results demonstrated reductions in the severity of AVHs, mood, anxiety, imagery frequency, and appraisals.Conclusions: imagery techniques appear feasible and acceptable for addressing mental imagery and AVHs in the psychosis continuum and may be valuable additions to current treatment for AVHs

Evaluation of activity and function before and immediately after the provision of a microprocessor knee in individuals with transfemoral amputation

BACKGROUND: In many cases, individuals with lower limb amputation become less active because of impaired balance and stability and increased risk of falling. Microprocessor knees (MPKs) have been shown to reduce the risk of falls, improve balance, and increase function, evaluated with self-reported scales and questionnaires. This study aims at investigating whether the patient-reported improvements are reflected in objective physical activity (PA) parameters estimated from actimetry sensors and assess the short-term provision of an MPK.STUDY DESIGN: Transfemoral amputee patients (n=29) undertaking an MPK trial at 2 prosthetic centers in the South of England were recruited for this study. Self-reported and functional test outcomes (Activities Balance Confidence, Reintegration of Normal Living Index, Prosthesis Evaluation Questionnaire scores, and 2-min walk test) were obtained before and after (4 weeks) the provision of the MPK. Activity levels were recorded over 7 consecutive days pre- and post-MPK.RESULTS: Self-reported scores and function test outcomes showed a general improvement in most of the patients after the provision of the MPK, with a statistically significant change ( p &lt; 0.05) in Activities Balance Confidence, Reintegration of Normal Living Index, Prosthesis Evaluation Questionnaire scores, and 2-min walk test. By contrast, the activity-based parameters estimated from actimetry showed no statistically significant changes ( p &gt; 0.05). Associations between self-reported and functional outcomes and actimetry parameters were limited.CONCLUSIONS: Perceived and in-clinic outcome measures improved after short-term provision of an MPK for transfemoral amputees. However, PA did not change in this cohort of patients over the study period. More longitudinal studies are needed to characterize the impact of MPK provision on PA and societal participation.</p

Multimodal large language models in human-centered health: practical insights

Multimodal data offer a comprehensive view of human health by integrating diverse sources, such as text, medical images, physiological signals, and behavioral data. Recent advancements in large language models (LLMs) have led to the development of multimodal large language models (MLLMs), which leverage the text understanding capabilities of LLMs and integrate them with other modalities. While MLLMs show great promise for human-centered health applications, the practical challenges of implementing them in the healthcare sector remain largely unexplored. This article discusses these practical considerations and the future potential of MLLMs in transforming human-centered healthcare.</p

Diagnostic performance of single-lead electrocardiograms from a smartwatch and a smartring for cardiac arrhythmia detection

Background: wearable devices are widely used for atrial fibrillation (AF) detection, yet most validation studies include only sinus rhythm or AF, likely overestimating diagnostic performance.Objective: this multicenter study assessed the performance of automated AF detection and physician interpretation of single-lead electrocardiograms (SL-ECGs) from the Apple Watch and CART Ring.Methodology: participants underwent simultaneous 12-lead ECG and SL-ECGs from Apple Watch and CART Ring. Two cardiologists independently adjudicated all ECGs. Apple Watch and CART Ring classified recordings as “AF,” “Not AF,” or “Unclassified.” Diagnostic performance for automated AF detection was evaluated in “worst-case” (all SL-ECGs) and lenient (excluding unclassified SL-ECGs) scenarios. Physician interpretation of SL-ECGs was also compared to 12-lead ECG.Results: among 483 patients (median age, 66 years; 29% female), 196 (39%) had AF across 3 United Kingdom centers. A total of 2398 ECGs were analyzed. Interobserver variability was excellent (Cohen’s kappa: Apple Watch, 0.85; CART Ring, 0.84). In the “worst-case” analysis, CART Ring outperformed Apple Watch (sensitivity, 84.6% vs 69.1%; specificity, 89.9% vs 72.6%). Apple Watch had more unclassified SL-ECGs (20.1%) than CART Ring (1.9%). The lenient analysis showed an improvement in sensitivity (CART Ring, 84.8 %; Apple Watch, 86.4%) and specificity (CART Ring, 91.2%; Apple Watch, 91.7%). Physician interpretation improved diagnostic performance for AF and sinus rhythm but remained limited for other arrhythmias.Conclusion: Apple Watch missed approximately 1 in 3 episodes of AF and a high number of unclassified SL-ECG. CART Ring demonstrated superior performance. Physician interpretation significantly improved AF diagnosis but remained unreliable for other arrhythmias, emphasizing the need for cautious integration of wearable ECGs into clinical practice

Type I X-ray burst emission reflected into the eclipses of EXO 0748-676

The neutron star X-ray binary, EXO 0748--676, was observed regularly by the Rossi X-ray Timing Explorer (RXTE) and XMM-Newton during its first detected outburst (1985 - 2008). These observations captured hundreds of asymmetric, energy-dependent X-ray eclipses, influenced by the ongoing ablation of the companion star and numerous Type I thermonuclear X-ray bursts. Here, we present the light curves of 22 Type I X-ray bursts observed by RXTE that coincide, fully or partially, with an X-ray eclipse. We identify nine instances where the burst occurs entirely within totality, seven bursts split across an egress, and six cases interrupted by an ingress. All in-eclipse bursts and split bursts occurred while the source was in the hard spectral state. We establish that we are not observing direct burst emission during eclipses since the companion star and the ablated outflow entirely obscure our view of the X-ray emitting region. We determine that the reflected flux from the outer accretion disc, even if maximally flared, is insufficient to explain all observations of in-eclipse X-ray bursts and instead explore scenarios whereby the emission arising from the X-ray bursts is scattered, either by a burst-induced rise in $N_{\rm{H}}$ that provides extra material, an accretion disc wind or the ablated outflow into our line of sight. However, the rarity of a burst and eclipse overlap makes it challenging to determine their origin