Nonlinear contractions involving simulation functions in a metric space with a partial order

Very recently, Khojasteh, Shukla and Radenovic [F. Khojasteh, S. Shukla, S. Radenovic, Filomat, 29 (2015), 1189-1194] introduced the notion of Z-contraction, that is, a nonlinear contraction involving a new class of mappings namely simulation functions. This kind of contractions generalizes the Banach contraction and unifies several known types of nonlinear contractions. In this paper, we consider a pair of nonlinear operators satisfying a nonlinear contraction involving a simulation function in a metric space endowed with a partial order. For this pair of operators, we establish coincidence and common fixed point results. As applications, several related results in fixed point theory in a metric space with a partial order are deduced

Stochastic multi-objective optimization for flood control in multi-reservoir systems: an adaptive Progressive Hedging approach with scenario clustering

IntroductionFlood-prone regions face growing challenges due to climate-induced variability, rapid urbanization, and competing demands on water infrastructure. Multi-reservoir systems play a critical role in mitigating flood damages, but climate change has intensified management complexity through increased hydroclimatic volatility and reduced reaction times for dam operators.MethodsThis study presents a stochastic multi-objective optimization framework that integrates ensemble-based inflow scenarios, high-resolution hydraulic simulations, and an adaptive version of the Progressive Hedging Algorithm enhanced by K-means scenario clustering. The approach was applied to Tunisia's Medjerda River basin, focusing on five interconnected reservoirs. The model balances downstream flood risk reduction with long-term water storage security by optimizing reservoir release policies across 1,000 synthetic inflow scenarios, reduced to 10 representative scenarios through clustering.ResultsThe proposed method achieved robust performance with normalized objective values of 0.087 for storage security and 0.094 for flood control. More than 93% of simulated scenarios satisfied both storage and flood-related constraints, demonstrating superior reliability compared to traditional rule-based methods (60–70%). The framework converged in 42 iterations with a computational time of 3.2 hours, representing a 6.7-fold reduction compared to full-scenario optimization while maintaining only 6–7% performance degradation. Peak discharge reductions of 25–30% were achieved through coordinated reservoir operations.DiscussionThe framework provides operationally feasible release policies that perform consistently across diverse flood conditions while significantly reducing computational costs. By combining hydrological realism with optimization scalability, this work supports the design of resilient and anticipatory flood management strategies in semi-arid regions, directly contributing to global efforts toward sustainable water governance (SDG 6), climate resilience (SDG 13), and disaster risk reduction in human settlements (SDG 11)

Adaptive vehicle routing for humanitarian aid in conflict-affected regions: a practitioner-informed deep reinforcement learning approach

Humanitarian aid delivery in conflict-affected regions faces significant challenges due to dynamic security risks, uncertain demand, and complex operational constraints. Traditional optimization methods struggle with computational intractability and lack adaptability for real-time decision-making in volatile environments. To address these limitations, we propose a novel hybrid framework that integrates Deep Reinforcement Learning (DRL) with Graph Neural Networks (GNNs) and deterministic constraint validation, informed by practitioner insights to ensure real-world applicability. Our approach employs Proximal Policy Optimization (PPO) enhanced by GNN-based spatial representations to learn adaptive, efficient vehicle routing policies under uncertainty. A post-decision validation mechanism enforces feasibility by penalizing constraint violations based on a deterministic equivalent model. We evaluate our method on realistic, georeferenced datasets reflecting Afghan road networks and conflict data, comparing it against classical PPO and heuristic baselines. Results demonstrate that PPO-GNN significantly reduces operational costs (by 7.9%), security risk exposure (by 15.2%), and unmet demand, while improving reliability and adherence to constraints. The approach scales effectively across network sizes and maintains robustness under stochastic variations in demand and security conditions. Our framework balances computational efficiency with practical relevance, aligning with humanitarian priorities and offering a promising decision-support tool for aid logistics in conflict zones

Data Mining to Identify the Right Interventions for the Right Patient for Heart Failure: A Real-World Study

Objectives To identify the right interventions for the right heart failure (HF) patients in the real-world setting using machine learning (ML) trained on individual-level clinical data linked with social determinants of health (SDOH) data. Methods In this retrospective cohort study, point-of-care claims data from Komodo Health and SDOH data from the National Health and Wellness Survey (NHWS), from January 2014–December 2020, were linked. Data mining was conducted using K-means clustering, an ML tool. Komodo Health data were used to access longitudinal data for the selected patient cohorts and cross-sectional data from NHWS for additional patient information. The primary outcome was HF-related hospitalizations; secondary outcomes, all-cause hospitalization and all-cause mortality. Use of digital healthcare (DHC)/non-DHC interventions and related outcomes were also assessed. Results The study population included 353 HF patients (mean age, 63.5 years; 57.2% women). The use of non-DHC (75.9%–81.9%) and DHC (4.0%–9.1%) interventions increased from baseline to follow-up. Overall, 17.0% of patients had HF-related hospitalizations (DHC, 6.9%; non-DHC, 16.5%) and 45.0% had all-cause hospitalization (DHC, 75.0%; non-DHC, 50.9%). Two archetypes with distinct patient profiles were identified. Archetype 1 (vs. 2) characterised by older age, greater disease severity, more comorbidities, more medication use, took steps to prevent heart attack/problems, had better lifestyle, higher HF-related hospitalizations (18.3% vs. 16.3%) and lower all-cause hospitalizations (42.9% vs. 46.3%). The trends remained the same regardless of the intervention type. Conclusions Identification of patient archetypes with distinct profiles can be useful to understand underlying disease subtypes, identify specific interventions, predict clinical outcomes, and define the right intervention for the right patient

Rotational transitions induced by collisions of HD+^{+} ions with low energy electrons

A series of Multichannel Quantum Defect Theory-based computations have been performed, in order to produce the cross sections of rotational transitions (excitations $N_{i}^{+}-2 \rightarrow$ $N_{i}^{+}$, de-excitations $N_{i}^{+}$ $\rightarrow$ $N_{i}^{+}-2$, with $N_{i}^{+}=2$ to $10$) and of their competitive process, the dissociative recombination, induced by collisions of HD$^+$ ions with electrons in the energy range $10^{-5}$ to 0.3 eV. Maxwell anisotropic rate coefficients, obtained from these cross sections in the conditions of the Heidelberg Test Storage Ring (TSR) experiments ($k_{B}T_{t}=2.8$ meV and $k_{B}T_{l}=45$ $\mu$eV), have been reported for those processes in the same electronic energy range. Maxwell isotropic rate coefficients have been as well presented for electronic temperatures up to a few hundreds of Kelvins. Very good overall agreement is found between our results for rotational transitions and the former theoretical computations as well as with experiment. Furthermore, owing to the full rotational computations performed, the accuracy of the resulting dissociative recombination cross sections is considerably improved.Comment: 9 pages, 8 figures, 1 table. arXiv admin note: text overlap with arXiv:1107.526

Treatment patterns, outcomes, healthcare resource utilization, and costs associated with locally advanced squamous cell carcinoma of the head and neck in Japan

ObjectiveTreatment patterns and healthcare resource utilization (HCRU) data in patients with locally advanced (stage III to IVB) squamous cell carcinoma of the head and neck (LA SCCHN) in Japan are limited. This study describes the patient demographics and characteristics, treatment patterns, HCRU, and costs among Japanese patients with newly diagnosed LA SCCHN.MethodsThis longitudinal, observational, retrospective study was conducted using real-world medical claims data from the Medical Data Vision Co., Ltd. database in Japan (1 January 2015–31 July 2022). Patients aged ≥18 years at the index date (first date of locally advanced head and neck cancer [HNC] diagnosis) and having a confirmed diagnosis of HNC during 01 January 2016–30 June 2021 in the oral cavity, larynx, hypopharynx, or oropharynx (based on ICD-10 diagnostic codes) were included. Baseline demographic and clinical characteristics were collected during the pre-index period. Treatment patterns, HCRU, and associated costs were reported during the post-index period.ResultsOf the included 6741 patients with LA SCCHN, 51.3% received definitive nonsurgical treatment, 32.4% underwent primary resection, and 16.1% did not receive any agent. The most common chemotherapy agent used for chemoradiotherapy was cisplatin (74.7%). Docetaxel, cisplatin, and 5-fluorouracil combination (TPF) was used as induction chemotherapy for 28.6% of patients who received induction treatment followed by surgery and in 55.6% of patients who received induction treatment followed by radiotherapy. Patients receiving primary resection were typically older than those receiving definitive nonsurgical treatment for each cancer site and stage. Almost all patients had ≥1 all-cause hospitalizations with substantial HCRU-associated costs.ConclusionsThis real-world study demonstrates that treatment of patients with LA SCCHN in Japan often included definitive nonsurgical treatment or primary surgery. The substantial burden related to LA SCCHN-associated HCRU and considerable percentage of patients receiving no treatment highlights a need for novel and effective therapies for LA SCCHN

Fixed points for cyclic R-contractions and solution of nonlinear Volterra integro-differential equations

In this paper, we introduce the notion of cyclic R-contraction mapping and then study the existence of fixed points for such mappings in the framework of metric spaces. Examples and application are presented to support the main result. Our result unify, complement, and generalize various comparable results in the existing literature.http://link.springer.com/journal/11784am2016Mathematics and Applied Mathematic

Drug utilization patterns and healthcare resource use and costs in patients with neurogenic bladder in the United Kingdom:A retrospective primary care database study

AIM: To characterize patients with neurogenic bladder (NGB), their treatment patterns, healthcare resource utilization, and associated costs based on records from a primary care database in the United Kingdom.METHODS: This was a retrospective, descriptive, observational study of anonymized data from the Clinical Practice Research Datalink and Hospital Episode Statistics databases (selection period, 1 January 2004 to 31 December 2016). Adults with a definitive or probable diagnosis of NGB and ≥1 referral to a urologist were included.RESULTS: The study cohort included 3913 patients with definitive (n = 363) or probable (n = 3550) NGB. Patients had a mean of 8.6 (standard deviation [SD], 7.6) comorbidities, and mean Anticholinergic Cognitive Burden Scale score of 6.6 (SD, 5.9). During 12 months' follow-up, urinary tract infection (UTI) and urinary incontinence were the most common complications. Most patients (92.2%) received ≥1 prescription for an antimuscarinic agent or mirabegron, and 53.9% of patients received prescriptions for UTI-specific antibiotics. The mean number of visits to a general practitioner for any cause was 67.7 (SD, 42.6) per individual. Almost half (46.7%) of the study cohort visited a specialist during the 12-month follow-up period, and 11.0% had ≥1 hospital admission. Total mean per patient costs for healthcare resource utilization was £2395.CONCLUSIONS: The burden of illness, healthcare resource needs, and associated costs among patients with NGB are considerable. Drug prescribing patterns are consistent with the symptoms and complications of NGB, although increased awareness of drugs with anticholinergic activity among prescribers may help to reduce the cumulative anticholinergic burden in this vulnerable population.</p