Ultimate Fate Research Articles

Predicting spatial curvature ΩK in globally CPT -symmetric universes

Boyle and Turok’s CPT-symmetric universe model posits that the Universe was symmetric at the big bang, addressing numerous problems in both cosmology and the Standard Model of particle physics. We extend this model by incorporating the symmetric conditions at the end of the Universe, which impose constraints on the allowed perturbation modes. These constrained modes conflict with the integer wave vectors required by the global spatial geometry in a closed universe. To resolve this conflict, only specific values of curvature are permissible, and in particular the curvature density is constrained to be ΩK∈{−0.016,−0.011,−0.004,…}, consistent with observations. Published by the American Physical Society 2024

Characteristics of deep-sea microbial cellulases: key determinants of the ultimate fate of plant biomass on Earth

AbstractLand plants, especially those with significant woody biomass, represent the largest source of biomass on Earth, making the biodegradation of lignocellulosic materials critical to understanding the global carbon cycle. Cellulose, a major component of lignocellulose, is notoriously resistant to degradation due to its highly crystalline structure. While the degradation of cellulose by terrestrial microbes has been extensively studied, the mechanisms of cellulose degradation in deep-sea environments remain largely unexplored. The deep-sea ecosystem depends on organic matter, such as cellulose, that is synthesized in terrestrial environments and surface waters and descends to the deep sea. Recent studies suggest that a significant amount of cellulose is likely to reach the deep sea. Here, we present an in-depth study of cellulases from a novel deep-sea γ-proteobacterial strain TOYAMA8, isolated from Toyama Bay, Japan, using Surface Pitting Observation Technology (SPOT), a highly sensitive assay for enzymatic cellulose hydrolysis. The cellulases of strain TOYAMA8 show similarities to those of a previously reported deep-sea cellulolytic microbe, Marinagarivorans cellulosilyticus strain GE09. Genomic and transcriptomic analyses of these strains reveal novel cellulase genes and mechanisms that differ from terrestrial counterparts, shedding light on the unique adaptations of deep-sea microbes to recalcitrant biomass. In particular, these strains produce high-molecular-weight cellulases with unique domain architectures, likely optimized for membrane anchoring, which prevents enzyme diffusion and ensures efficient localized activity. Our findings provide critical insights into the microbial cellulose degradation in the deep sea, highlighting its role in the fate of organic carbon and the potential for biotechnological applications in biorefineries.

Ferroptosis in diabetic cardiomyopathy: from its mechanisms to therapeutic strategies

Diabetic cardiomyopathy (DCM) is defined as structural and functional cardiac abnormalities in diabetes, and cardiomyocyte death is the terminal event of DCM. Ferroptosis is iron-dependent oxidative cell death. Evidence has indicated that iron overload and ferroptosis play important roles in the pathogenesis of DCM. Mitochondria, an important organelle in iron homeostasis and ROS production, play a crucial role in cardiomyocyte ferroptosis in diabetes. Studies have shown some anti-diabetic medicines, plant extracts, and ferroptosis inhibitors might improve DCM by alleviating ferroptosis. In this review, we systematically reviewed the evidence of ferroptosis in DCM. Anti-ferroptosis might be a promising therapeutic strategy for the treatment of DCM.

RADT-44. EARLY CLINICAL EXPERIENCE WITH PROTON CRANIOSPINAL IRRADIATION FOR THE TREATMENT OF LEPTOMENINGEAL DISEASE

Abstract BACKGROUND Leptomeningeal disease (LMD) is a uniformly terminal event of advanced cancer with limited therapeutic options, with survival ranging from weeks to a few months. Recently, proton craniospinal irradiation (pCSI) has been demonstrated to confer a progression-free and overall survival benefit in select patients with LMD as compared to more limited site radiotherapy. Early results from an institutional experience of pCSI for patients with LMD from solid tumor malignancies are reviewed. METHODS All patients with LMD and treated with pCSI at our institution were reviewed, specifically with regards to baseline patient characteristics, radiation dosimetry parameters and clinical outcomes. RESULTS Between February 2023-April 2024, nine patients were treated with pCSI for a range of primary tumor histologies, including two with triple-negative breast cancer and one each with ER+/PR+/HER2- breast cancer, non-small cell lung cancer, small cell lung cancer, gastric cancer, esophageal cancer, pancreatic cancer and ovarian cancer. All patients received 30Gy(RBE) in 10 fractions to the craniospinal axis, with one patient receiving an intracranial boost (6Gy(RBE)). Median age and performance status was 58 years and KPS 80, respectively. Five (56%) patients underwent CSF diversion prior to pCSI, 22% of patients had undergone prior CNS-directed radiotherapy, and all patients received at least one line of systemic therapy in the metastatic setting prior to pCSI. Median survival from the first day of pCSI was 4.3 months (range 1.3-10.7mo). Median survival among patients undergoing CSF diversion prior to pCSI (n=5) was 5.3 months (vs. 2.9mo with no CSF diversion). Median survival among patients who received systemic treatment after pCSI (n=5) was 9.1 months (vs. 2.9mo for patients who did not). CONCLUSIONS Careful patient selection is imperative to identify those who will best benefit from pCSI with suggestion of patients undergoing pre-pCSI CSF diversion and receiving post-pCSI systemic therapy achieving superior survival.

The Prenuptial Agreement of Business Spouses: Guarantees of Respect for Mutual Interests and Protection of the Rights of the Parties

Introduction: in the light of modern socio-economic realities, an urgent problem is the effective protection of the property interests and rights of spouses who own a family business. The conclusion of a prenuptial agreement provides spouses who have a family business and are parties to the prenuptial agreement with the opportunity to reduce financial risks and provide themselves with additional legal protection in the event of termination of the marital relationship. The inclusion of legally verified contractual structures in a prenuptial agreement is very effective in preventing future conflicts between spouses who own a joint business. Purpose: to reveal the legal content of the prenuptial agreement concluded between spouses who own a joint business in the system of contractual structures and to develop recommendations for improving the contractual regulation. Objectives: to identify conflicts related to the legal guarantees of respect for mutual interests of spouses who have a family business and are parties to a prenuptial agreement; to identify contractual structures used to minimize conflicts between the subjects of a prenuptial agreement; and to develop a conceptual model for concluding a prenuptial agreement between spouses who own a joint business remotely via the Internet. Methods: the methodological framework for the research is based on the general scientific methods: systematic analysis, abstraction, and the dialectical method, as well as a set of specific scientific methods: structural and functional, formal legal, comparative law, forecasting, and modeling. Results: it is proposed to amend Art. 11 of Federal Law No. 193-FZ dated July 27, 2010, “On an Alternative Dispute Settlement Procedure with the Participation of an Intermediary (Mediation Procedure),” supplementing its paragraph 8; in the context of the effective implementation of the concept of “Electronic State,” the Federal Notary Chamber it is proposed to develop, test, and implement a virtual assistant based on artificial intelligence technologies, which will function not only on the Federal Notary Chamber website but also on the online resources of the notary chambers of the constituent entities of the Russian Federation. Conclusions: it is recommended to normalize the mediation procedure for spouses who have a family business and are parties to a prenuptial agreement through information and communication technologies; as part of the implementation of the concept of “Electronic State,” the Federal Notary Chamber should develop, test, and implement a virtual assistant (“chatbot”) based on artificial intelligence, which will be available not only on the Federal Notary Chamber website but also on the websites of notary chambers of the constituent entities of the Russian Federation, and at the request of users, including spouses who have a joint family business, it will perform an advisory function when drafting a prenuptial agreement.

Global Prediction of Flash Drought Using Machine Learning

AbstractFlash droughts are rapidly developing extreme weather events with sudden onset and quick intensification. Global prediction of flash droughts at sub‐seasonal time scales remains a great challenge. Current state‐of‐the‐art dynamic models subject to large errors and demonstrate low skills in global flash drought prediction. Here, we develop a machine learning‐based framework that uses meteorological forecasts as inputs to predict global root‐zone soil moisture and flash droughts from 1 day to 2 week lead times. The results indicate that 33% and 24% global flash drought onset and termination events can be correctly predicted by machine learning at 7 day lead time, versus 19% and 11% fractions by state‐of‐the‐art dynamic model. The developed machine learning model demonstrates substantial improvements over dynamic model in global soil moisture prediction, and thus enhances global flash drought forecasting skills in space and time. The presented framework may benefit global flash drought prediction and early warning at sub‐seasonal scales.

The new fate of MCLR revealed by dialysis equilibrium and theoretical calculations: Influence from DOM and Fe(II)/Mn(II)

Microcystin-LR (MCLR) is a highly toxic pollutant widely distributed in eutrophic waters. The interplay between dissolved organic matter (DOM) and metal ions has been extensively reported; however, the impact of DOM-metal complexes on MCLR remains to be thoroughly studied. In this research, equilibrium dialysis was employed to study the kinetics and isotherms of MCLR adsorption by DOM, meanwhile the Density functional theory (DFT) calculations provided insights into the theoretical mechanisms of Fe(II)/Mn(II) involvement in the adsorption process. The adsorption kinetics revealed that the process is physicochemical, with chemisorption being the critical factor controlling the adsorption rate. The adsorption isotherms confirmed that Fe(II) alters the spatial arrangement of adsorption sites on the superficies of DOM, with the complexes of Fe(II) and DOM from the macrophyte-dominated regions of Lake Taihu (MDR-Fe(II)) showing the uppermost adsorption capacity of 6193.965 µg/g among all combinations. The influence of different cations (K+, Ca2+, Na+, Mg2+) on the adsorption of MCLR to DOM is divergent, with metals either reducing MCLR adsorption through competition for adsorption sites or increasing it by forming ternary complexes. The pH decrease reduced the affinity of DOM to metal ions while simultaneously enhancing MCLR adsorption through changes in its ionization state. DFT calculations demonstrated that Fe(II)/Mn(II) reduces the resistance to interaction between functional groups on DOM and MCLR, with carboxyl-Fe(II)-carboxyl interactions showing the highest binding energy (ΔG = −7.253 eV). Overall, Fe(II)/Mn(II) enhances the adsorption of MCLR via altering the structure and surface electrostatic potential distribution of DOM. This research indicates that the ultimate fate of MCLR in aquatic ecosystems is affected by DOM and metal ions.

What Happens after Nora Walks Out?——Take Regret for the Past and A Room of One’s Own as Examples to Analyze Female Liberation

At the commencement of the 20th century, concurrent with the transformation of the socioeconomic structure and the augmentation of individualistic consciousness, the feminist narrative in both the Eastern and Western contexts grew increasingly assertive. The character Nora in Ibsen’s plays significantly contributed to the consciousness awakening among women. Regret for the Past can serve as a sequel to What Happens after Nora Walks Out? Delineating the roads and ultimate fate of a consciousness-awakened woman. Concurrently, the eminent Western author, Virginia Woolf, initiated an exploration of feminism within the narrative of A Room of One’s Own marking a significant juncture in the Western feminist movement’s trajectory. This scholarly work involves a meticulous exegesis of the literary texts within Regret for the Past and A Room of One’s Own, examining the diverse experiences of women’s liberation across various historical periods. Research indicates that the status of women has enhanced subsequent to societal emancipation, with women’s liberation being concomitant with their endeavor for gender equality. Subsequently, the Women’s Liberation Movement has achieved additional advancements. It is incontrovertible that research has demonstrated the necessity of social emancipation as a prerequisite for the advancement of women’s liberation. Presently, given the enhancement of women’s societal standing, when running away from home, which had been given the meaning of awakening, was no longer the only option. What contemporary avenues are available for women and what novel challenges confront the cause of women’s liberation?

Developing new methods for patient care pathway assessment for breast cancer patients in Hungary

Abstract Issue The idea of progressive healthcare models is to treat patients preferably in one location as close to their homes as possible. This contradicts the demands of efficiency: to centralise the availability of expensive procedures and highly specialised staff. Healthcare systems need to navigate between these challenges, especially in public health issues such as cancer care. Description of the problem Achieving the best possible health outcomes requires evidence-based policies that find balance between the demands of accessibility and efficiency. Therefore, we aimed to set up a methodology to review the healthcare model and assess patient movements across the system. We analysed the roaming paths of breast cancer patients diagnosed in Hungary in 2017. Inter-hospital roaming was represented as a graph: hospitals were the nodes, patient movements from one hospital to another were directed edges. This allowed us to apply network analysis: modularisation, weighted degrees calculation, etc. We then introduced the measure of terminality. A hospital is terminal in a given pathway if it is the last new one, i.e. all hospitals visited later had already been visited before. Terminality is defined as the proportion of terminal events among all pathways that cross a given hospital. The rationale of this is that the last hospital in cancer pathways is usually not the highest level one: after advanced treatments, patients are often referred back to local hospitals. Results Testing the method on Hungarian breast cancer patients we observed that results fit our prior expectations. The official ranking of hospitals on the progressivity scale (reflecting the availability of advanced treatments) shows sufficient agreement with terminality. Minor differences may point to situations where the healthcare system does not work fully according to regulations. Lessons Our methodology is recommended for system level patient pathway analysis in order to develop evidence-based healthcare policies. Key messages • Graph representation of inter-hospital patient roaming supports evidence-based policy developments for more efficient patient pathways in cancer care, regardless of the healthcare system design. • The applied new network analysis methodology can help assessing the real life processes of cancer care in a healthcare system through identifying the specifics of inter-hospital patient movements.

Efficacy of sotagliflozin by diabetes duration: a secondary analysis of SCORED

Abstract Background Sotagliflozin is a sodium-glucose cotransporter (SGLT) 1 and SGLT2 inhibitor. SCORED randomized patients with type 2 diabetes (DM) and high cardiovascular (CV) risk to sotagliflozin or placebo. Purpose We evaluated if diabetes duration affects HF and CV outcomes when comparing sotagliflozin with placebo in SCORED, as diabetes duration can modify CV risk. Methods SCORED enrolled patients with DM (hemoglobin A1c ≥7%), chronic kidney disease (glomerular filtration rate of 25-60 mL/minute per 1.73 m2), and CV risk factors. Patients were randomized to sotagliflozin compared with placebo. Patients in SCORED were stratified by diabetes duration, into categories of <10 years, 10-19 years, or ≥20 years. The primary endpoint was total CV death, hospitalization for HF, or urgent visit for HF. Secondary endpoints were total hospitalization for HF or urgent visit for HF, as well as total CV death, nonfatal myocardial infarction, and nonfatal stroke (MACE). Outcomes were assessed using marginal proportional hazard models stratified according to HF criteria and geographic region where non-CV death was a competing terminal event. Subgroup analyses were assessed with natural cubic splines of interaction between treatment and continuous diabetes duration. Results In SCORED, 10,579 (99.9%) of 10,584 patients had complete data on diabetes duration, with 2412 (22.8%), 4424 (41.8%), 3743 (25.9%) having diabetes duration of <10, 10-19, and ≥20 years respectively. Median (Q1, Q3) diabetes duration was 16.4 years (10.4, 22.4 years), while mean hemoglobin A1c was 8.6%, 8.7%, and 8.7% respectively by diabetes duration. The rate of the primary endpoint was lower in the sotagliflozin group (5.6 events per 100 patient-years [p-y]) compared with the placebo group (7.5 events per 100 p-y) (HR: 0.74; 95% CI: 0.63, 0.88). Event rates among diabetes duration subgroups indicated that rates in both the placebo group and relative treatment benefit increased with increasing diabetes duration, with 5.6 vs 5.8 events per 100 p-y, 6.1 vs 7.4 events per 100 p-y, and 4.6 vs 8.5 events per 100 p-y for diabetes duration <10, 10-19, and ≥20 years respectively. Spline analysis indicated increasing treatment benefit with increasing duration when modeled continuously (Figure Panel A; PSpline=0.02). Similar findings were observed for the secondary HF outcome of hospitalization for HF or urgent visit for HF, with increased treatment benefit with duration (Figure Panel B; PSpline=0.10). Total MACE was lower in the sotagliflozin group (4.8 events per 100 patient-years) than in the placebo group (6.3 events per 100 patient-years) (HR: 0.77; 95% CI: 0.65, 0.91), without significant difference in relative treatment benefit by duration (Figure Panel C; PSpline=0.30). Conclusions Sotagliflozin improved HF and MACE outcomes in patients with high CV risk, with increasing treatment benefit for HF outcomes among patients with longer diabetes duration.

Two-stage pseudo maximum likelihood estimation of semiparametric copula-based regression models for semi-competing risks data.

We propose a two-stage estimation procedure for a copula-based model with semi-competing risks data, where the non-terminal event is subject to dependent censoring by the terminal event, and both events are subject to independent censoring. With a copula-based model, the marginal survival functions of individual event times are specified by semiparametric transformation models, and the dependence between the bivariate event times is specified by a parametric copula function. For the estimation procedure, in the first stage, the parameters associated with the marginal of the terminal event are estimated using only the corresponding observed outcomes, and in the second stage, the marginal parameters for the non-terminal event time and the copula parameter are estimated together via maximizing a pseudo-likelihood function based on the joint distribution of the bivariate event times. We derived the asymptotic properties of the proposed estimator and provided an analytic variance estimator for inference. Through simulation studies, we showed that our approach leads to consistent estimates with less computational cost and more robustness than the one-stage procedure developed in Chen YH (Lifetime Data Anal 18:36-57, 2012), where all parameters were estimated simultaneously. In addition, our approach demonstrates more desirable finite-sample performances over another existing two-stage estimation method proposed in Zhu H et al., (Commu Statistics-Theory Methods 51(22):7830-7845, 2021) . An R package PMLE4SCR is developed to implement our proposed method.

Shared parameter modeling of longitudinal data allowing for possibly informative visiting process and terminal event.

Joint modeling of longitudinal and time-to-event data, particularly through shared parameter models (SPMs), is a common approach for handling longitudinal marker data with an informative terminal event. A critical but often neglected assumption in this context is that the visiting/observation process is noninformative, depending solely on past marker values and visit times. When this assumption fails, the visiting process becomes informative, resulting potentially to biased SPM estimates. Existing methods generally rely on a conditional independence assumption, positing that the marker model, visiting process, and time-to-event model are independent given shared or correlated random effects. Moreover, they are typically built on an intensity-based visiting process using calendar time. This study introduces a unified approach for jointly modeling a normally distributed marker, the visiting process, and time-to-event data in the form of competing risks. Our model conditions on the history of observed marker values, prior visit times, the marker's random effects, and possibly a frailty term independent of the random effects. While our approach aligns with the shared-parameter framework, it does not presume conditional independence between the processes. Additionally, the visiting process can be defined on either a gap time scale, via proportional hazard models, or a calendar time scale, via proportional intensity models. Through extensive simulation studies, we assess the performance of our proposed methodology. We demonstrate that disregarding an informative visiting process can yield significantly biased marker estimates. However, misspecification of the visiting process can also lead to biased estimates. The gap time formulation exhibits greater robustness compared to the intensity-based model when the visiting process is misspecified. In general, enriching the visiting process with prior visit history enhances performance. We further apply our methodology to real longitudinal data from HIV, where visit frequency varies substantially among individuals.

Possible mechanism of effect of the empagliflozin on cardiovascular mortality

Introduction. The development of heart failure is closely associated with the appearance of life threatening arrhythmias, which are often a terminal event for these patients. An analysis of randomized clinical trials of inhibitors of sodium-glucose cotransporter type 2 indicates the clinically significant potential of these drugs as agents with antiarrhythmic properties. However, at the moment the full mechanism by which this effect can be realized is still not fully understood.Aim. To evaluate the effect of empagliflozin on the transmembrane calcium currents and the intracellular calcium transients on isolated ventricular cardiomyocytes of mice under conditions of normoglycemia.Materials and methods. In the experiment, ventricular cardiomyocytes were isolated from 12 outbred male mice. 2 groups were formed: group № 1 – control ventricular cardiomyocytes; group № 2 – ventricular cardiomyocytes after two hours incubation with 5 µmol/L empagliflozin solution. Transmembrane calcium currents were recorded and intracellular calcium transients were assessed.Results and discussion. Incubation of ventricular cardiomyocytes with empagliflozin significantly increased ICa current density and accelerated Ca2+ temporal dynamics. The amplitude of the Ca2+ wave and the rate of rise and decay were increased and the duration of the Ca2+ wave was shortened.Conclusion. The result of the experiment indicates that empagliflozin is able to modulate Ca2+-dependent mechanism of the excitation-contraction-coupling, enhancing and accelerating Ca2+ release into cytoplasm and reuptake. This presumably can optimize, namely reduce the time of systole and enhance it, which may be one of the important elements in the manifestation of empagliflozin antiarrhythmic properties.

Conditional modeling of recurrent event data with terminal event.

Recurrent event data with a terminal event arise in follow-up studies. The current literature has primarily focused on the effect of covariates on the recurrent event process using marginal estimating equation approaches or joint modeling approaches via frailties. In this article, we propose a conditional model for recurrent event data with a terminal event, which provides an intuitive interpretation of the effect of the terminal event: at an early time, the rate of recurrent events is nearly independent of the terminal event, but the dependence gets stronger as time goes close to the terminal event time. A two-stage likelihood-based approach is proposed to estimate parameters of interest. Asymptotic properties of the estimators are established. The finite-sample behavior of the proposed method is examined through simulation studies. A real data of colorectal cancer is analyzed by the proposed method for illustration.

Evidence for a lipofibroblast-to- Cthrc1 + myofibroblast reversible switch during the development and resolution of lung fibrosis in young mice.

Fibrosis is often associated with aberrant repair mechanisms that ultimately lead to organ failure. In the lung, idiopathic pulmonary fibrosis (IPF) is a fatal form of interstitial lung disease (ILD) to which there is currently no curative therapy. From the cell biology point of view, the cell of origin and eventual fate of activated myofibroblasts (aMYFs) have taken center stage as these cells are believed to drive structural remodeling and lung function impairment. While aMYFs are now widely believed to originate from resident fibroblasts, the heterogeneity of aMYFs and ultimate fate during fibrosis resolution remain elusive. We have previously shown that aMYFs dedifferentiation and acquisition of a lipofibroblast (LIF)-like phenotype represent a route of fibrosis resolution. In this study, we combined genetic lineage tracing and single-cell transcriptomics in mice, and data mining of human IPF datasets to decipher the heterogeneity of aMYFs and investigate differentiation trajectories during fibrosis resolution. Furthermore, organoid cultures were utilized as a functional readout for the alveolar mesenchymal niche activity during various phases of injury and repair in mice. Our data demonstrate that aMYFs consist of four subclusters displaying unique pro-alveologenic versus profibrotic profiles. Alveolar fibroblasts displaying a high LIF-like signature largely constitute both the origin and fate of aMYFs during fibrogenesis and resolution respectively. The heterogeneity of aMYFs is conserved in humans and a significant proportion of human aMYFs displays a high LIF signature. Our work identifies a subcluster of aMYFs that is potentially relevant for future management of IPF.

Tetrabromobisphenol A biotransformation in aged soil: Mechanism analysis induced by root exudates during rhizoremediation of Helianthus annus

Rhizoremediation, recognized as a progressive strategy for the removal of organic pollutants in soil, prominently focused on the influence of root exudates-induced alterations within the rhizosphere on the bioavailability and transformation of pollutants. However, the influence of root exudates on the ultimate fate of tetrabromobisphenol A (TBBPA) in soil remains unclear. The current study embarked on a comprehensive examination of the biotransformation process and underlying mechanisms of TBBPA driven by root exudates of Helianthus annus in rhizospheric soil. The pot experiment underscored the constructive impact of root exudates on enhancing the TBBPA dissipation efficiency within lab-controlled, with the increments of 18.77 %∼38.64 %. The core bacterial players responsible for TBBPA biotransformation were identified, with the prominent genus being Saccharibacteria_genera_incertae_sedis, unclassified_Sphingomonadaceae, and Parcubacteria_genera_incertae_sedis. In rhizospheric soil, a comprehensive analysis disclosed the presence of 20 different biotransformation products of TBBPA. Notably, root exudates were found to predominantly drive the reductive debromination pathway. This study provided for the first concrete evidence that root exudates can promote the desorption of TBBPA from soils. The current study aimed to decipher the molecular mechanisms in biotransformation process of TBBPA mediated by root exudates, and also provided reference for the environmental behavior of organic pollutants induced by root exudates.

Embracing mortality: psychological preparation on death in the guidance of stoic philosophy

Humanity's greatest fear is the inevitability of death, the ultimate fate that all strive to evade. This collective dread of mortality stems from its perceived malevolence. Across the ages, from religious rituals promising salvation to scientific efforts to delay death, human attempts to confront mortality vary widely. Yet death remains inescapable, a natural consequence of life. While religious doctrines offer comfort through ideas of an afterlife, and science views death as a biological challenge to be postponed. Conversely, philosophy advocates for an intellectual acceptance of death's inevitability. The Stoic Philosophy, in particular, advocate for the joyful acceptance of death as an integral part of life. This philosophical stance fosters a positive perspective on death, encouraging individuals to live life to its fullest potential. Embracing death with joy entails psychological reassurance and preparatory measures for life's inevitable end. This qualitative study explores psychological preparation for death using primary and secondary data sources. Primary sources include the philosophical texts by Seneca and Marcus Aurelius, specifically "Letters to Lucilius," "On the Shortness of Life," and "Meditations." Secondary data is collected from peer-reviewed journals, books, and reports that contextualize these works within modern psychological frameworks. The primary audience includes individuals preparing for death due to age or illness and those grieving loved ones, offering a pathway to peace and understanding through Stoic wisdom. Moreover, this will be a guidance to those who work with the terminally ill people to get psychological resilience. By embracing death, Stoicism encourages both the dying and the bereaved to find psychological reassurance and encourage all to live a meaningful life in the given time frame.

Biosurfactant-mediated transport of tetracycline antibiotics in saturated porous media: Combined effects of the chemical properties of contaminants and solution chemistry conditions

The mobility of tetracycline antibiotics (TCs) in saturated aquifers is possibly affected by the presence of biosurfactants, which are widespread in the aquatic/soil environments. This study investigated the mobility characteristics of various tetracyclines—specifically tetracycline (TC), oxytetracycline (OTC), and chlortetracycline (CTC)—within quartz sand columns in the presence of rhamnolipid, a common biosurfactant. Exogenous rhamnolipid significantly inhibited the transport of the three TCs over the pH range of 5.0–9.0 (e.g., the mass of retained TC, OTC, and CTC increased from 32.6 %, 26.9 %, and 39.2 % (in the absence rhamnolipid) to 39.4 %, 38.9 %, and 51.7 % (in the presence of rhamnolipid), respectively). This observation could be attributed to the bridging effects of this biosurfactant. Specifically, the hydrophilic head of rhamnolipid molecules is likely associated with the surfaces of sand grains through surface complexation and/or hydrogen bonding interactions. Accordingly, the hydrophobic moieties of the deposited rhamnolipid molecules (i.e., the aliphatic chains) interact with the hydrophobic groups of TCs molecules via hydrophobic interactions. Interestingly, the extent of the inhibitory effect on CTC mobility was greater than that on OTC and TC, which was related to the different hydrophobic characteristics of the three antibiotics. Furthermore, the inhibitory effect of rhamnolipid on the transport of TCs diminished as the pH of the background solution increased. This observation was attributed to the weakened bridging effects, resulting from the reduced deposition of the biosurfactant on the sand surfaces. Additionally, the cation-bridging mechanism involved in the retention of TCs in the addition of rhamnolipid when the background electrolyte was Ca2+ (i.e., Ca2+ ions served as bridging agents between the deposited rhamnolipid molecules and TCs). The insightful findings enhance our understanding of the critical roles of biosurfactants in influencing the environmental dynamics and ultimate fate of conventional antibiotic pollutants within groundwater systems.

Accelerating universe in [formula omitted] gravity

This paper investigates the dynamics of cosmic expansion within the framework of f(R,Lm) gravity, focusing on the late-time behavior of the universe modeled as a flat Friedmann-Lemaître-Robertson-Walker spacetime. We derive an analytical solution for the field equations and employ advanced statistical techniques, including the Markov Chain Monte Carlo (MCMC) method, to determine best-fit values for the key cosmological parameters, such as the Hubble parameter and the deceleration parameter. Our findings reveal a transition from a decelerating to an accelerating phase of cosmic expansion, aligning closely with observational data as in the ΛCDM model. The analysis of energy conditions indicates that the strong energy condition is violated, in keeping with the current accelerated expansion of the universe and the nature of dark energy. By elucidating the quintessence behavior of our model through statefinder and Om diagnostics, this study contributes to a deeper understanding of cosmic evolution and the fundamental forces at play. The insights gained pave the way for future research into alternative cosmological models, inviting further exploration of the mysteries surrounding dark energy and the ultimate fate of the universe.

CHARA Near-infrared Imaging of the Yellow Hypergiant Star ρ Cassiopeiae: Convection Cells and Circumstellar Envelope

Massive evolved stars such as red supergiants and hypergiants are potential progenitors of Type II supernovae, and they are known for ejecting substantial amounts of matter, up to half their initial mass, during their final evolutionary phases. The rate and mechanism of this mass loss play a crucial role in determining their ultimate fate and the likelihood of their progression to supernovae. However, the exact mechanisms driving this mass ejection have long been a subject of research. Recent observations, such as the Great Dimming of Betelgeuse, have suggested that the activity of large convective cells, combined with pulsation, could be a plausible explanation for such mass-loss events. In this context, we conducted interferometric observations of the famous yellow hypergiant, ρ Cassiopeiae using the CHARA Array in H- and K-band wavelengths. ρ Cas is well known for its recurrent eruptions, characterized by periods of visual dimming (∼1.5–2 mag) followed by recovery. From our observations, we derived the diameter of the limb-darkened disk and found that this star has a radius of 1.04 ± 0.01 mas, or 564–700 R ⊙. We performed image reconstructions with three different image reconstruction software packages, and they unveiled the presence of giant hot and cold spots on the stellar surface. We interpret these prominent hot spots as giant convection cells, suggesting a possible connection to mass ejections from the star’s envelope. Furthermore, we detected spectral CO emission lines in the K band (λ = 2.31–2.38 μm), and the image reconstructions in these spectral lines revealed an extended circumstellar envelope with a radius of 1.45 ± 0.10 mas.