PubMed İndeksli Yayınlar Koleksiyonu / PubMed Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/20.500.11779/1928
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Article Mice Extrapolate Temporal Information Based on Previously Learned Spatiotemporal Mappings: An Asymmetrical Case(Springer, 2026-01-06) Gur, Ezgi; Duyan, Yalcin A.; Toptas, Pinar; Balci, FuatOne of the computational affordances of isomorphic magnitude representations is the extrapolation of temporal information based on previously experienced spatiotemporal pairings. We initially trained mice on the association of two intervals (10 s and 30 s) with two hoppers (H2 and H4, counterbalanced) in a five-choice nose-poke box with the following setup. One of the three novel hoppers (H1) neighbored H2 only, the other novel hopper (H5) neighbored H4 only, and the third novel hopper (H3) neighbored H2 and H4 (H1Novel -> H2Trained -> H3Novel -> H4Trained -> H5Novel). During test trials, one of the five hoppers was illuminated. We estimated the trial time at which the anticipatory response rate was maximal (peak time) separately for each hopper. Mice extrapolated temporal information only in a forward fashion; the peak time for H5 was longer than that for H4. Mice did not extrapolate temporal information backward; the timed response curves in H1 and H3 were closely similar to those in H2. Thus, our findings suggest that mice can extrapolate temporal information, but also indicate that the computations underlying this process are directionally constrained. We discuss the possible reasons behind asymmetrical extrapolation.Article Citation - WoS: 1Citation - Scopus: 1Understanding Covid-19 Mobility Through Human Capital: a Unified Causal Framework(Springer, 2023-02-21) Bilgel, Fırat; Karahasan, Burhan CanThis paper seeks to identify the causal impact of educational human capital on social distancing behavior at workplace in Turkey using district-level data for the period of April 2020 - February 2021. We adopt a unified causal framework, predicated on domain knowledge, theory-justified constraints anda data-driven causal structure discovery using causal graphs. We answer our causal query by employing machine learning prediction algorithms; instrumental variables in the presence of latent confounding and Heckman's model in the presence of selection bias. Results show that educated regions are able to distance-work and educational human capital is a key factor in reducing workplace mobility, possibly through its impact on employment. This pattern leads to higher workplace mobility for less educated regions and translates into higher Covid-19 infection rates. The future of the pandemic lies in less educated segments of developing countries and calls for public health action to decrease its unequal and pervasive impact.Article Citation - WoS: 5Citation - Scopus: 6Monitoring of Intracerebral Hemorrhage With a Linear Microwave Imaging Algorithm(Springer, 2022-10-29) Dilman, Ismail; Dogu, Semih; Bilgin, Egemen; Akinci, Mehmet Nuri; Cosgun, Sema; Çayören, Mehmet; Akduman, IbrahimIntracerebral hemorrhage is a life-threatening condition where conventional imaging modalities such as CT and MRI are indispensable in diagnosing. Nevertheless, monitoring the evolution of intracerebral hemorrhage still poses a technological challenge. We consider continuous monitoring of intracerebral hemorrhage in this context and present a differential microwave imaging scheme based on a linearized inverse scattering. Our aim is to reconstruct non-anatomical maps that reveal the volumetric evolution of hemorrhage by using the differences between consecutive electric field measurements. This approach can potentially allow the monitoring of intracerebral hemorrhage in a real-time and cost-effective manner. Here, we devise an indicator function, which reveals the position, volumetric growth, and shrinkage of hemorrhage. Later, the method is numerically tested via a 3D anthropomorphic dielectric head model. Through several simulations performed for different locations of intracerebral hemorrhage, the indicator function-based technique is demonstrated to be capable of detecting the changes accurately. Finally, the robustness under noisy conditions is analyzed to assess the feasibility of the method. This analysis suggests that the method can be used to monitor the evolution of intracerebral hemorrhage in real-world scenarios. Graphical abstract: [Figure not available: see fulltext.]. © 2022, International Federation for Medical and Biological Engineering.Article Citation - WoS: 7Citation - Scopus: 9Hematocrit Levels and Thrombotic Events in Patients With Polycythemia Vera: an Analysis of Veterans Health Administration Data(Springer, 2019-09-24) Parasuraman, Shreekant; Robyn Scherber; Jingbo Yu; Li Wang; Dilan Paranagama; Sulena Shrestha; Başer, Onur; Yu, Jingbo; Paranagama, Dilan; Shrestha, Sulena; Scherber, Robyn; Wang, LiPatients with polycythemia vera (PV) have a high incidence of thrombotic events (TEs), contributing to a greater mortality risk than the general population. The relationship between hematocrit (HCT) levels and TE occurrence among patients with PV from the Veterans Health Administration (VHA) was evaluated to replicate findings of the CYTO-PV trial with a real-world patient population. This retrospective study used VHA medical record and claims data from the first claim with a PV diagnosis (index) until death, disenrollment, or end of study, collected between October 1, 2005, and September 30, 2012. Patients were aged ? 18 years at index, had ? 2 claims for PV (ICD-9-CM code, 238.4) ? 30 days apart during the identification period, continuous health plan enrollment from 12 months pre-index until end of study, and ? 3 HCT measurements per year during follow-up. This analysis focused on patients with no pre-index TE, and with all HCT values either < 45% or ? 45% during the follow-up period. The difference in TE risk between HCT groups was assessed using unadjusted Cox regression models based on time to first TE. Patients (N = 213) were mean (SD) age 68.9 (11.5) years, 98.6% male, and 61.5% white. TE rates for patients with HCT values < 45% versus ? 45% were 40.3% and 54.2%, respectively. Among patients with ? 1 HCT before TE, TE risk hazard ratio was 1.61 (95% CI, 1.03–2.51; P = 0.036). This analysis of the VHA population further supports effective monitoring and control of HCT levels < 45% to reduce TE risk in patients with PV.Article Citation - WoS: 30Citation - Scopus: 29Out-Of Inr Values and Outcomes Among New Warfarin Patients With Non-Valvular Atrial Fibrillation(Springer, 2014-11-27) Schein, Jeffrey R; Wang, Li; Damaraju, Chandrasekharrao, V; Nelson, Winnie W; Başer, OnurBackground Although efficacious in stroke prevention in non-valvular atrial fibrillation, many warfarin patients are sub-optimally managed. Objective To evaluate the association of international normalized ratio control and clinical outcomes among new warfarin patients with non-valvular atrial fibrillation. Setting Adult non-valvular atrial fibrillation patients (a parts per thousand yen18 years) initiating warfarin treatment were selected from the US Veterans Health Administration dataset between 10/2007 and 9/2012. Method Valid international normalized ratio values were examined from the warfarin initiation date through the earlier of the first clinical outcome, end of warfarin exposure or death. Each patient contributed multiple in-range and out-of-range time periods. Main outcome measure The relative risk ratios of clinical outcomes associated with international normalized ratio control were estimated. Results 34,346 patients were included for analysis. During the warfarin exposure period, the incidence of events per 100 person-years was highest when patients had international normalized ratio < 2:13.66 for acute coronary syndrome; 10.30 for ischemic stroke; 2.93 for transient ischemic attack; 1.81 for systemic embolism; and 4.55 for major bleeding. Poisson regression confirmed that during periods with international normalized ratio < 2, patients were at increased risk of developing acute coronary syndrome (relative risk ratio: 7.9; 95 % confidence interval 6.9-9.1), ischemic stroke (relative risk ratio: 7.6; 95 % confidence interval 6.5-8.9), transient ischemic attack (relative risk ratio: 8.2; 95 % confidence interval 6.1-11.2), systemic embolism (relative risk ratio: 6.3; 95 % confidence interval 4.4-8.9) and major bleeding (relative risk ratio: 2.6; 95 % confidence interval 2.2-3.0). During time periods with international normalized ratio > 3, patients had significantly increased risk of major bleeding (relative risk ratio: 1.5; 95 % confidence interval 1.2-2.0). Conclusion In a Veterans Health Administration non-valvular atrial fibrillation population, exposure to out-of-range international normalized ratio values was associated with significantly increased risk of adverse clinical outcomes.