julilili42/papers huggingface dataset:
Spatio‐Temporal Variability of Hyporheic Exchange Processes Across a Stream Network
2024-12-01

ABSTRACT Hyporheic exchange processes (HEP) play a critical role in controlling riverine biogeochemical turnover and ecological functioning. Despite the expected scaling of HEP across stream networks, only limited knowledge exists about how HEP changes over the hydrological year and across the stream network. This study investigates spatial and temporal changes in HEP in a second‐ to fourth‐order stream network in southern Germany. We employed radon, an environmental tracer commonly used for quantifying HEP, to study the relationships between HEP and discharge. Numerical mass‐balance modelling was applied to quantify HEP, and we specifically focused on the hyporheic area ( A s ) and the stream's cross‐sectional area ( A ). Our findings showed a decrease in A s /A with increasing stream order, indicating changes of HEP across the stream network. The absence of a correlation of A s with discharge implies that the scaling of HEP may be influenced by a combination of discharge and local heterogeneities in stream geomorphology. Temporal variability in HEP was observed over the hydrological year, with the highest variability in headwater streams. Lower A s values were noted in headwaters during summer compared to the other seasons and coincided with an increased groundwater contribution to the streamflow and decreased stream discharge. Although neither stream or groundwater discharge were identified as driving factors for reduced HEP in the headwaters during summer, our findings suggest that hydrological processes that lead to decreased streamflow in headwaters may have influenced HEP further downstream in the stream network. This is evidenced by the larger A s / A ratios observed in higher‐order streams during summer compared to other seasons. These findings highlight the necessity for comprehensive investigations of HEP processes over the hydrological year and across the whole stream network.
Broad ligament ectopic pregnancy with full-term live birth: a rare case report from Syria
2024-12-01

Abstract Ectopic pregnancy, the implantation of a fertilized zygote outside the uterine cavity, presents with abdominal pain and vaginal bleeding. Diagnosis relies on clinical signs, and treatment involves surgery or methotrexate in selected cases. A 24-year-old woman at 37 weeks of gestation underwent elective cesarean delivery under general anesthesia, revealing an unexpected broad ligament ectopic pregnancy. The live fetus and placenta were successfully delivered without complications. The study reports a rare asymptomatic broad ligament ectopic pregnancy until 37 weeks, diagnosed by laparotomy—treatment involved removing the ovary and placenta and preserving the uterus. A healthy male baby and mother recovered well. This rare ectopic pregnancy, with placental implantation in the broad ligament, resulted in a successful cesarean delivery of a healthy infant and complication-free recovery, highlighting the importance of timely diagnosis and skilled surgical intervention.
Morphology of the stem group echinoids Lepidocentrus eifelianus and Rhenechinus hopstaetteri from the Devonian of the Eifel region, Germany
2024-12-01

Abstract Relatively well-preserved echinoids from Palaeozoic strata are exceptionally rare fossils. New fossil finds can thus have an important impact on our understanding of the morphology, phylogenetic relationships and history of diversification of early sea urchins. The Devonian strata of Germany have long been known to contain echinoids, predominantly through the relatively abundant record of disarticulated plates and spines. In contrast, only select articulated or semi-articulated specimens are recorded. We herein describe new specimens from the Middle and Late Devonian belonging to two Palaeozoic echinoid taxa, Rhenechinus hopstaetteri and Lepidocentrus eifelianus . These specimens are amongst the most-complete known for these two taxa, and provide novel insight into their morphology and stratigraphic range. Additionally, the record of Rhenechinus is the youngest occurrence of an echinocystitid echinoid in the fossil record, indicating that this family ranged from the Silurian (Aeronian or Telychian) to at least the Middle Devonian (Givetian), prior to going extinct. The morphological details provided by the new specimen of L. eifelianus highlights similarities between this species and other Devonian echinoids known from elsewhere in Europe and North America, and suggest that the lepidocentrids were widely dispersed and abundant during the Devonian.
Text+ – Concept and Benefits for Empirical Researchers
2024-12-01

Abstract In this contribution, we report on ongoing efforts in the German national research infrastructure consortium Text+ to make research data and services for text- and language-oriented disciplines FAIR, that is findable, accessible, interoperable, and reusable, as well as compliant with the CARE principles for language resources.
A generalizable data‐driven model of atrophy heterogeneity and progression in a memory clinic setting
2024-12-01

Abstract Background Memory clinic patients are a heterogeneous population representing various aetiologies of pathological aging. It is unknown if divergent spatiotemporal progression patterns of brain atrophy, as previously described in Alzheimer’s disease (AD) patients, are prevalent and clinically meaningful in this group of older adults. Method To uncover atrophy subtypes, we applied the Subtype and Stage Inference (SuStaIn) algorithm to structural MRI data from 813 participants (mean ± SD age = 70.67 ± 6.07 years, 52% females) from the DELCODE cohort. Participants were cognitively unimpaired (CU; n = 285) or patients with subjective cognitive decline (SCD; n = 342), mild cognitive impairment (MCI; n = 118), or dementia of the Alzheimer’s type (n = 68). Atrophy subtypes were compared in baseline demographics, fluid AD biomarkers, and domain‐specific cognitive performance. PACC‐5 trajectories over up to 240 weeks were examined. Clinical trajectories (PACC‐5 scores and MCI conversion rates) in only CU and SCD participants were analysed. SuStaIn modelling was repeated in participants from the Swedish BioFINDER‐2 study for replication and generalizability testing. Result Limbic‐predominant and hippocampal‐sparing atrophy subtypes were identified (Figure 1). Limbic‐predominant atrophy first affected the medial temporal lobes, followed by further temporal and, finally, the remaining cortical regions. This subtype was related to older age, more pathological AD biomarkers, APOE ε4 carriership, and an amnestic cognitive impairment. Hippocampal‐sparing atrophy initially occurred outside the temporal lobe and spared the medial temporal lobe until advanced stages. This atrophy pattern also affected individuals with positive AD biomarkers and was associated with more generalised cognitive impairment. Limbic‐predominant atrophy, in all and in only unimpaired participants, was linked to more negative longitudinal PACC‐5 slopes than observed in participants without or with hippocampal‐sparing atrophy (Figure 2) and increased the risk of MCI conversion. In BioFINDER‐2, analogous atrophy subtypes and cognitive correlates were identified. Group‐ and subject‐level model generalizability were excellent, indicating reliable performance in novel data (Figure 3). Conclusion The proposed model is a promising tool for capturing heterogeneity among older adults at early at‐risk states for AD in applied settings. The implementation of atrophy subtype‐ and stage‐specific end‐points may increase the statistical power of pharmacological trials targeting early AD.
CSF ATN and α‐synuclein co‐pathology in AD, PD, and DLB
2024-12-01

Abstract Background Co‐pathology between Alzheimer’s disease (AD), Parkinson’s disease (PD), and dementia with Lewy bodies (DLB) remains poorly understood but is relevant for trial design. We aimed to compare CSF markers of amyloid, tau, and neurodegeneration (ATN) and α‐synuclein between AD, PD, DLB and controls, and investigate the influence of demographical, genetic, and clinical factors on amyloid positivity. Method As part of the EPND study, we included 337 individuals with AD, PD, DLB and controls from 6 centers. CSF Aß 1‐42 , p‐tau 181 , NfL, and α‐Syn were centrally measured using NeuroToolKit (Roche Diagnostics International Ltd), and clinical data were harmonized. Controls were individuals with normal cognition and normal Aß 1‐42 . AD was defined as abnormal Aß 1‐42 without meeting clinical criteria of DLB or PD. Data were analyzed by general linear models adjusted for age and sex. Result 38% individuals were female, and mean age was 67 years. 170 individuals had AD, 74 PD, 66 DLB, and 27 were controls (Table 1). AD individuals showed lower Aß 1‐42 levels compared to all other groups (Figure 1). DLB individuals had lower Aß 1‐42 levels than those with PD, with both groups displaying lower levels than controls. P‐tau 181 concentrations were higher in AD relative to DLB and PD (both p&lt;0.001), with DLB showing higher (p=0.013) and PD lower (p=0.007) levels than controls. Relative to controls, α‐Syn levels were lower in AD, DLB and PD (p=0.016, p=0.016, and p=0.019, respectively). NfL levels were higher in AD (p=0.003) and DLB (p=0.009) compared to controls. 80% of DLB and 58% of PD individuals were amyloid‐positive. Compared to amyloid‐negative ones, amyloid‐positive DLB and PD individuals had lower α‐Syn levels (both p&lt;0.001, Figure 2). Amyloid‐positive PD individuals had lower p‐tau 181 levels compared to amyloid‐negative ones (p&lt;0.001). No differences were observed between amyloid‐positive and negative DLB and PD individuals regarding NfL levels. Age, sex, APOE‐ε4, MMSE, and MDS‐UPDRS‐III score were not related to amyloid positivity in DLB and PD. Conclusion Amyloid pathology is highly prevalent in DLB and PD and associated with lower α‐synuclein levels. α‐Synuclein levels are also decreased in AD. This highlights overlapping pathologies in AD, DLB and PD and has significant implications for clinical trial designs.
Abnormalities in task‐fMRI activation are related to disease progression towards Alzheimer’s disease
2024-12-01

Abstract Background Differences in task‐fMRI activation have recently been found to be related to neuropathological hallmarks of AD. However, the evolution of fMRI‐based activation throughout AD disease progression and its relationship with other biomarkers remains elusive. Applying a disease progression model (DPM) to a multicentric cohort with up to four annual task‐fMRI visits, we hope to provide a deeper insight into these relationships. Method We estimated AD disease stages using a multivariate Gaussian Process (GP) DPM including CSF‐Aβ42/40 ratio, CSF‐p‐tau 181 , hippocampal and entorhinal volume, ADAS13‐Cog sum and PACC5 scores. Disease stages from 493 participants with longitudinal task‐fMRI measurements from DELCODE (165 healthy controls (CN), 214 participants with SCD, 82 with MCI, 32 with suspected AD) were obtained. We derived subsequent memory and novelty contrasts from a visual memory encoding task using general linear modeling (GLM). Contrasts from all available follow‐ups were then submitted to voxel‐based group‐level GLM analyses. Activations from resulting disease‐stage‐related clusters were (1) used to estimate cluster‐level trajectory curves over disease stages using smoothing splines and (2) submitted to linear‐mixed effects models to test longitudinal changes over follow‐ups. Result Our DPM‐derived disease stages were associated with clinical groups, fMRI performance and white matter lesions (Figure 1C‐F). Generally, in both contrasts, activation increases were observed in task‐negative clusters while activation decreases were observed in task‐positive clusters (Figure 2C‐F). We did not find indications for inverted u‐shaped associations between disease stage and activation in whole brain voxel‐wise cross‐sectional analyses. However, smoothing splines revealed non‐linear monotonically increasing biomarker abnormality for task‐negative areas, showing earliest changes towards the beginning of disease progression. After a plateau, fMRI activation increases in abnormality conjointly with volume changes. For task‐positive areas, we observed linear relationships with disease stages (Figure 3). Activation changes over follow‐ups were not associated with disease stages. Conclusion Biomarker abnormality timing in our DPM reflected hypothetical AD progression. Changes in task‐fMRI activation and deactivation were both associated with progression towards AD. Smoothing spline fits indicated abnormality changes in task‐fMRI activation to begin in the earliest phases of the disease. Findings can be discussed as differential pathophysiological processes such as complex reorganization and neural noise.
Predicting the risk of cognitive decline and speech impairment in the preclinical stage of Alzheimer's disease using structural MRI
2024-12-01

Abstract Background Speech abnormalities are increasingly recognized as a manifestation of cognitive deficits in Alzheimer's disease (AD) and its preclinical and prodromal stages. Here, we investigated whether MRI measures of brain atrophy, specifically in the basal forebrain and cortical language areas, can predict cognitive decline and speech difficulties in older adults within the AD spectrum. Method The ongoing Prospect‐AD study aims to develop an algorithm to automatically identify speech biomarkers in individuals with early signs of AD. We recruited participants for the Prospect‐AD study from the German national cohort studies DELCODE and DESCRIBE. Within Prospect‐AD, we captured speech recordings via automated phone calls in healthy controls and people with preclinical and prodromal AD. Speech features were extracted from the semantic verbal fluency (SVF) task of automated telephone conversations, using artificial intelligence‐based analysis of the audio recordings. We combined the speech data from Prospect‐AD with the clinical and imaging data from DELCODE and DESCRIBE, including socio‐demographic information, baseline AD diagnosis, neuropsychology, CSF amyloid status, and MRI scans. We used mixed‐effects regression to estimate the association of rates of cognitive decline and traits of automatically obtained speech features with regional atrophy. Result To date, we enrolled 220 participants in the Prospect‐AD study, 103 of whom are included in this report. Our participants underwent baseline clinical examinations and MRI scans between 2014 and 2022 (mean age = 68.1, SD=5.7 years, 67% female, mean MMSE score = 29.2, SD=1.3, CDR global score ≤0.5) with annual follow‐up over 4.9 years (SD=2.5 years) and successfully completed the baseline phone assessment in 2022‐2023. The results will be presented at the conference. Conclusion Automated speech‐based cognitive testing may assist in low‐threshold identification of older adults at higher risk for clinical progression to AD which in turn may assist in allocation of clinical resources. In future analyses, we will further investigate associations of cognitive performance and speech features with structural or functional connectivity changes in the brain using DTI or functional MRI data.
A generalizable data‐driven model of atrophy heterogeneity and progression in a memory clinic setting
2024-12-01

Abstract Background Memory clinic patients are a heterogeneous population representing various aetiologies of pathological aging. It is unknown if divergent spatiotemporal progression patterns of brain atrophy, as previously described in Alzheimer’s disease (AD) patients, are prevalent and clinically meaningful in this group of older adults. Method To uncover atrophy subtypes, we applied the Subtype and Stage Inference (SuStaIn) algorithm to structural MRI data from 813 participants (mean ± SD age = 70.67 ± 6.07 years, 52% females) from the DELCODE cohort. Participants were cognitively unimpaired (CU; n = 285) or patients with subjective cognitive decline (SCD; n = 342), mild cognitive impairment (MCI; n = 118), or dementia of the Alzheimer’s type (n = 68). Atrophy subtypes were compared in baseline demographics, fluid AD biomarkers, and domain‐specific cognitive performance. PACC‐5 trajectories over up to 240 weeks were examined. Clinical trajectories (PACC‐5 scores and MCI conversion rates) in only CU and SCD participants were analysed. SuStaIn modelling was repeated in participants from the Swedish BioFINDER‐2 study for replication and generalizability testing. Result Limbic‐predominant and hippocampal‐sparing atrophy subtypes were identified (Figure 1). Limbic‐predominant atrophy first affected the medial temporal lobes, followed by further temporal and, finally, the remaining cortical regions. This subtype was related to older age, more pathological AD biomarkers, APOE e4 carriership, and an amnestic cognitive impairment. Hippocampal‐sparing atrophy initially occurred outside the temporal lobe and spared the medial temporal lobe until advanced stages. This atrophy pattern also affected individuals with positive AD biomarkers and was associated with more generalised cognitive impairment. Limbic‐predominant atrophy, in all and in only unimpaired participants, was linked to more negative longitudinal PACC‐5 slopes than observed in participants without or with hippocampal‐sparing atrophy (Figure 2) and increased the risk of MCI conversion. In BioFINDER‐2, analogous atrophy subtypes and cognitive correlates were identified. Group‐ and subject‐level model generalizability were excellent, indicating reliable performance in novel data (Figure 3). Conclusion The proposed model is a promising tool for capturing heterogeneity among older adults at early at‐risk states for AD in applied settings. The implementation of atrophy subtype‐ and stage‐specific end‐points may increase the statistical power of pharmacological trials targeting early AD.
Digital biomarker co‐design with patients and caregivers
2024-12-01

Abstract Background Using artificial intelligence approaches enable automated assessment and analysis of speech biomarkers for Alzheimer’s disease, for example using chatbot technology. However, current chatbots often are unsuitable for people with cognitive impairment. Here, we implemented a user‐centred‐design approach to evaluate and improve usability of a chatbot system for automated speech assessments for people with preclinical, prodromal and early dementia. Method Participants (n = 221 by January 2024, 300 planned, see Figure 1) of the PROSPECT‐AD study were automatically called for six times every three months by our chatbot “Mili”. In each call three cognitive tasks (Wordlist, Semantic Verbal Fluency, Story Telling) are offered. We applied the System Usability Scale (SUS) in all participants and conducted additional semi‐structured interviews in a subgroup to gain in‐depth information for improving Mili and adapting it to the users’ needs. During the interviews, we focus on affinity for technology and Mili’s usability. Result We collected usability data at M3 by the SUS from 163 participants (12 missings, ØAge: 73.2 years, SD: 6.6 years, see Figure 2) after their second call. The results indicated a good usability of Mili (ØSUS: 70.4/100, SD: 22.2). Within semi‐structured interviews we asked 22 participants (ØAge: 73.0 years, 12 female, ØMMST: 29.3, range 24‐30, medium tech‐savvy) for their ideas to improve the Mili system. We analysed the interviews using qualitative content analysis. Participants wished for an intelligent chatbot and a feedback system after each call about participants’ cognitive performance. In the event that the performance would indicate cognitive decline, Mili should provide information on local services for dementia, and give recommendations for prevention and advises for the user’s physician for medication. Seventeen interviewees (2 undecided, 3 negative) would like to use Mili regularly if they would receive a feedback on their cognitive performance. Conclusion Our results revealed a high usability and feasibility of the automated phone calls by Mili. Eligible feedback solutions would increase the usefulness and usage of remote testing if a they provide individual advises for prevention and contact persons. Unrealistic expectations on Mili regarding the recommendation of medication must be discussed with the users.
Dipolar ordering transitions in many-body quantum optics: Analytical diagrammatic approach to equilibrium quantum spins
2024-12-02

Quantum spin models with a large number of interaction partners per spin are\\nfrequently used to describe modern many-body quantum optical systems like\\narrays of Rydberg atoms, atom-cavity systems or trapped ion crystals. For\\ntheoretical analysis the mean-field (MF) ansatz is routinely applied. However,\\nbesides special cases of all-to-all or strong long range interactions, the MF\\nansatz provides only approximate results. Here we present a systematic\\ncorrection to MF theory based on diagrammatic perturbation theory for quantum\\nspin correlators in thermal equilibrium. Our analytic results are universally\\napplicable for any lattice geometry and spin-length S. We provide pre-computed\\nand easy-to-use building blocks for Ising, Heisenberg and transverse field\\nIsing models in the symmetry-unbroken regime. We showcase the quality and\\nsimplicity of the method by computing magnetic phase boundaries and excitations\\ngaps. We also treat the Dicke-Ising model of ground-state superradiance where\\nwe show that corrections to the MF phase boundary vanish.\\n
Challenges and Choices in Breastfeeding Healthy, Sick and Preterm Babies: Review
2024-12-02

Although breastfeeding is associated with many health-related benefits for both mothers and children, the WHO recommendation for exclusive breastfeeding is not achieved by the majority in any WHO region. This paper aims to present the current state of research on challenges and choices in breastfeeding healthy, sick and preterm babies. The research was organized as a systematic search in PubMed and the study was performed as a narrative review after applying the PRISMA protocol. Finally, n = 57 studies were included. Both barriers and support factors emerge as a complex interaction of individual, group and societal factors, the precise understanding of which is relevant to increasing breastfeeding rates in the future. Knowledge as well as practical skills proved to be generally helpful, whereas the lack of breastfeeding support for mothers, who are often separated from their premature babies in hospital, was identified as a key risk factor for this subgroup. Appropriate training for healthcare professionals can improve the situation as a result. After discharge, workplace-related barriers are of major concern to allow further breastfeeding when maternity leave ends. Thus, the promotion of breastfeeding must be perceived as a task for society as a whole.