Publications by authors named "Voelker A"

Time is a central dimension against which perception, action, and cognition play out. From anticipating when future events will happen to recalling how long ago previous events occurred, humans and animals are exquisitely sensitive to temporal structure. Empirical evidence seems to suggest that estimating time prospectively (i.

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Background: Managing degenerative lumbar diseases is challenging due to the complexity of identifying symptom causes, especially when multiple pathologies coexist. This study evaluated the impact of patient-specific lumbar spine infiltrations on therapeutic strategies in patients with multiple spinal pathologies (MSP) or specific spinal pathologies (SSP).

Methods: A retrospective cohort of 176 patients treated for subacute or chronic lumbar pain with targeted spinal infiltrations was analyzed.

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This study aimed to develop a graph neural network (GNN) for automated three-dimensional (3D) magnetic resonance imaging (MRI) visualization and Pfirrmann grading of intervertebral discs (IVDs), and benchmark it against manual classifications. Lumbar IVD MRI data from 300 patients were retrospectively analyzed. Two clinicians assessed the manual segmentation and grading for inter-rater reliability using Cohen's kappa.

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Species assemblage composition of marine microfossils offers the possibility to investigate ecological and climatological change on time scales inaccessible using conventional observations. Planktonic foraminifera - calcareous zooplankton - have an excellent fossil record and are used extensively in palaeoecology and palaeoceanography. During the Last Glacial Maximum (LGM; 19,000 - 23,000 years ago), the climate was in a radically different state.

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Calcium (Ca) is an essential nutrient for plants and a cellular signal, but excessive levels can be toxic and inhibit growth. To thrive in dynamic environments, plants must monitor and maintain cytosolic Ca homeostasis by regulating numerous Ca transporters. Here we report two signalling pathways in Arabidopsis thaliana that converge on the activation of vacuolar Ca/H exchangers (CAXs) to scavenge excess cytosolic Ca in plants.

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We present the first version of the Ocean Circulation and Carbon Cycling (OC3) working group database, of oxygen and carbon stable isotope ratios from benthic foraminifera in deep ocean sediment cores from the Last Glacial Maximum (LGM, 23-19 ky) to the Holocene (<10 ky) with a particular focus on the early last deglaciation (19-15 ky BP). It includes 287 globally distributed coring sites, with metadata, isotopic and chronostratigraphic information, and age models. A quality check was performed for all data and age models, and sites with at least millennial resolution were preferred.

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Article Synopsis
  • The study investigates the safety and effectiveness of different spinal injection types used in treating patients with degenerative spine disease, focusing on side effects and pain reduction.
  • A total of 48 patients received 282 injections, leading to reported common side effects like transient pain and nerve root irritation, with the highest complication rates from periradicular injections.
  • Although patients experienced significant pain relief and improvement in disability scores immediately post-treatment, many reported a relapse in symptoms by the 12-week follow-up.
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Purpose: To investigate the innervation pattern of the sacroiliac region, especially with regard to the sacroiliac joint (SIJ). Dorsal SIJ innervation was analyzed and described. Our main hypothesis was that nerves reach the SIJ dorsally, passing ligamental compartments, as this would explain dorsal SIJ pain.

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Objective: Convolutional neural networks (CNNs) are being increasingly used in the medical field, especially for image recognition in high-resolution, large-volume data sets. The study represents the current state of research on the application of CNNs in image segmentation and pathology detection in spine magnetic resonance imaging.

Methods: For this systematic literature review, the authors performed a systematic initial search of the PubMed/Medline and Web of Science (Core collection) databases for eligible investigations.

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  • The study evaluated post-embolic and postoperative outcomes of patients with renal cell carcinoma (RCC) metastases to the thoracic and lumbar spine at a single center from 2010 to 2020.* -
  • A total of 31 patients were assessed, with the results showing no significant differences in blood loss or complications between those with thoracic and lumbar spine metastases.* -
  • The findings suggest that embolization is safe and effective as a preoperative procedure, but surgery should occur the day after to better monitor for potential neurological complications.*
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Objective: The aim of the study was to assess the relationship between the expression of elastin, collagen type I, II,III and the degenera- tion of the facet joint capsule and the ligamentum flavum.

Methods: 10 patients (4 male, 6 female) (mean age 61 ± 14,9) undergoing surgery for degenerative lumbar spine syndrome and 5 cadav- ers (3 male, 2 female) (age of death 87 ± 8,6 years) were included in this study. One set of tissue samples was taken from each patient in the patient group intraoperatively and two sets of samples were taken from each cadaver in the cadaver group posthumosly from the ligamentum flavum (medial and lateral) and from the facet joint capsules (superior and inferior articular process) at the L4/5 segment.

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Purpose: Intraforaminal ligaments (IFL) are of great interest to anatomists and clinicians to fully understand the detailed anatomy of the neuroforamina and to diagnose unclear radicular symptoms. Studies published until now have described radiological imaging of the IFLs using magnetic resonance imaging (MRI) on donor bodies. In the present study, we investigated the detectability of lumbar IFLs in vivo in adults using the high spatial resolution of the constructive interference in steady state (CISS) sequence.

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  • The study developed a convolutional neural network (CNN) to analyze lumbar spinal muscles in MRI scans of patients with lower back pain, focusing on segmenting muscle and classifying fatty degeneration.
  • The CNN was trained using 3,650 axial T2-weighted MRI images from 100 patients and showed high accuracy in muscle segmentation but struggled with fatty tissue, achieving a dice similarity coefficient (DSC) of 0.51 for that aspect.
  • Despite promising results with overall muscle segmentation and a 75% accuracy in classification, the study indicates the need for larger datasets and additional model training to improve fatty tissue segmentation for clinical use.
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Introduction: Current agents for the intravascular embolization of traumatic hemorrhage are used off-label and have been minimally studied with respect to their performance under differing coagulation conditions. We studied the hemorrhage control efficacy of a novel, liquid, polyethylene glycol-based hydrogel delivered as two liquid precursors that polymerize within the target vessel in a unique animal model of severe solid organ injury with and without dilutional coagulopathy.

Methods: Anesthetized swine (n = 36, 45 ± 3 kg) had laparotomy and splenic externalization.

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Thiamine (vitamin B) is an essential micronutrient in the human diet, found both naturally and as a fortification ingredient in many foods and supplements. However, it is susceptible to degradation due to heat, light, alkaline pH, and sulfites, among effects from other food matrix components, and its degradation has both nutritional and sensory implications as in foods. Thiamine storage stability in solution was monitored over time to determine the effect of solution pH and thiamine concentration on reaction kinetics of degradation without the use of buffers, which are known to affect thiamine stability independent of pH.

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While neural networks are highly effective at learning task-relevant representations from data, they typically do not learn representations with the kind of symbolic structure that is hypothesized to support high-level cognitive processes, nor do they naturally model such structures within problem domains that are continuous in space and time. To fill these gaps, this work exploits a method for defining vector representations that bind discrete (symbol-like) entities to points in continuous topological spaces in order to simulate and predict the behavior of a range of dynamical systems. These vector representations are spatial semantic pointers (SSPs), and we demonstrate that they can (1) be used to model dynamical systems involving multiple objects represented in a symbol-like manner and (2) be integrated with deep neural networks to predict the future of physical trajectories.

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Thiamine is a water-soluble essential micronutrient, and grains are the main source of thiamine in the human diet. Refining processes reduce thiamine content; therefore, many flours are enriched with thiamine. Further processes, such as heating (baking), destabilize thiamine.

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Background: Due to the unspecific symptoms of spondylodiscitis (SpD), an early radiological examination is necessary. However, controversially discussed is the need for magnetic resonance imaging of the entire spine to exclude multisegmental infections and to determine the required surgical interventions. The aims of this study were to assess the incidence of multilevel non-contiguous pyogenic SpD and compare comorbidities, pain symptoms, and subsequent surgical strategies between unifocal (uSpD) and multifocal (mSpD) SpD.

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This study investigated thiamine degradation in thiamine mononitrate (TMN):polymer solid dispersions, accounting for the physical state of the vitamin and the recrystallization tendency of TMN in these dispersions. Results were compared with those from solid dispersions containing a different salt form of thiamine (thiamine chloride hydrochloride (TClHCl)). TMN:polymer dispersions were prepared by lyophilizing solutions containing TMN and amorphous polymers (pectin and PVP (polyvinylpyrrolidone)).

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The crystallization of amorphous sucrose in food products can greatly affect the quality of foods. This study investigated the effects of polyphenols on the crystallization of amorphous sucrose lyophiles. Monoglycosylated, polyglycosylated, and aglycones with differing polyphenol backbones were studied, in addition to bulk food ingredients containing a high concentration of polyphenols.

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The prevalence of nonspecific pyogenic spondylodiskitis, associated with both a high morbidity and a high mortality, has increased in the last few decades. The diagnosis is often delayed because of the nonspecific clinical manifestation at the early stage. The reliability of radiographs is limited, particularly in early stage after the onset of infection.

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Spices, herbs, and seasoning blends containing both crystalline and amorphous ingredients are common throughout the food industry but may exhibit unwanted clumping or caking during storage. Crystalline and amorphous ingredients are known to respond differently to increases in relative humidity (RH) and temperature. The aim of this study was to better characterize what happens to moisture sorption behaviors, water-solid interactions, and physical stability when crystalline and amorphous ingredients are co-formulated in seasoning blends.

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Thiamine is an essential micronutrient, but delivery of the vitamin in supplements or foods is challenging because it is unstable under heat, alkaline pH, and processing/storage conditions. Although distributed as a crystalline ingredient, thiamine chloride hydrochloride (TClHCl) likely exists in the amorphous state, specifically in supplements. Amorphous solids are generally less chemically stable than their crystalline counterparts, which is an unexplored area related to thiamine delivery.

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Background: Endovascular embolization is increasingly used in treating traumatic hemorrhage and other applications. No endovascular-capable translational large animal models exist and coagulopathy's effect on embolization techniques is unknown. We developed a coagulation-adaptable solid organ hemorrhage model in swine for investigation of embolization techniques.

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Radiometric dating of glacial terminations over the past 640,000 years suggests pacing by Earth's climatic precession, with each glacial-interglacial period spanning four or five cycles of ~20,000 years. However, the lack of firm age estimates for older Pleistocene terminations confounds attempts to test the persistence of precession forcing. We combine an Italian speleothem record anchored by a uranium-lead chronology with North Atlantic ocean data to show that the first two deglaciations of the so-called 100,000-year world are separated by two obliquity cycles, with each termination starting at the same high phase of obliquity, but at opposing phases of precession.

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