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We investigated the influence of context on students’ understanding of cross products of vectors using three isomorphic multiple-choice tests asking for the direction of a cross product in different geometrical settings. One version of the test involved the Lorentz force, the second version involved the torque on an electric dipole, and the third version was without physics context. We administered the tests to 216 first-year pre-med students at a Belgian (Flemish) university. We found that students perform significantly better in the context of the Lorentz force. Students more often chose the incorrect alternative corresponding to the vector sum in the test versions involving an electric dipole or without physics context when the vectors are not orthogonal. For orthogonal vectors, a sign error—i.e., inverting the direction of the resulting vector—was the most common mistake in both tests with physics context, while without physics context selecting the alternative corresponding to the sum remained the most common mistake. Prior familiarity with a right-hand rule in a specific context seems to be able to explain improved scores in the test version concerning the Lorentz force. Instructors and curriculum developers can benefit from adopting an integrated approach in which the mathematical aspects of the cross product are treated together with multiple examples in physics, allowing students to transition from using specific rules to determine a cross product, to a more integrated understanding of it.

Activity induced transcription factor ΔFosB plays a key role in different CNS disorders including epilepsy, Alzheimer's disease, and addiction. Recent findings suggest that ΔFosB drives cognitive deficits in epilepsy and together with the emergence of small molecule inhibitors of ΔFosB activity makes it an interesting therapeutic target. However, whether ΔFosB contributes to pathophysiology or provides protection in drug-resistant epilepsy is still unclear. In this study, ΔFosB was specifically downregulated by delivering AAV-shRNA into the hippocampus of chronically epileptic mice using the drug-resistant pilocarpine model of mesial temporal epilepsy (mTLE). Immunohistochemistry analyses showed that prolonged downregulation of ΔFosB led to exacerbation of neuroinflammatory markers of astrogliosis and microgliosis, loss of mossy fibers, and hippocampal granule cell dispersion. Furthermore, prolonged inhibition of ΔFosB using a ΔJunD construct to block ΔFosB signaling in a mouse model of Alzheimer's disease, that exhibits spontaneous recurrent seizures, led to similar findings, with increased neuroinflammation and decreased NPY expression in mossy fibers. Together, these data suggest that seizure-induced ΔFosB, regardless of seizure-etiology, is part of a homeostatic mechanism that protects the epileptic brain from further deterioration., Competing Interests: JCl, GM-C, TD, P-YC, MB, AF, and MR during conducting of the study were employed by UCB Biopharma SRL. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Clasadonte, Deprez, Stephens, Mairet-Coello, Cortin, Boutier, Frey, Chin and Rajman.)

Primary hyperoxaluria type 1 is a rare autosomal recessive disorder leading to oxalate overproduction by deficiency in the liver-specific enzyme alanine-glyoxylate transaminase (AGT). Oxalate is a poorly soluble molecule that binds calcium and deposits in the entire organism leading to oxalosis. Its elimination is mainly carried out by kidneys. Hence the first manifestations are frequently of urinary concern and whitout any early care, progression of the disease to end-stage renal failure cannot be avoided. The only etiological treatment has long been combined liver-kidney transplantation because it restaures enzymatic function and replaces pathological kidneys. However, for a few years now, numerous studies are carried out on this subject and promising results have already been published with a new drug, lumasiran. From a clinical case, we describe the different options for the therapeutic management of primary hyperoxaluria type 1.

With the emergence of disease-modifying therapies for Parkinson's disease, reliable longitudinal markers are needed to quantify pathology and demonstrate disease progression. We developed the A53T-AAV rat model of synucleinopathy by combining longitudinal measures over 12 weeks. We first characterized the progression of the motor and dopaminergic deficits. Then, we monitored the disease progression using the [ 18 F]FMT Positron Emission Tomography (PET) radiotracer. The nigral injection of A53T-AAV led to an increase in phosphorylated α-synuclein on S129, a progressive accumulation of α-synuclein aggregates, and a decrease of dopaminergic function associated with a deterioration of motor activity. The longitudinal monitoring of A53T-AAV rats with [ 18 F]FMT PET showed a progressive reduction of the K c outcome parameter in the caudate putamen from the lesioned side. Interestingly, the progressive reduction in the [ 18 F]FMT PET signal correlated with defects in the stepping test. In conclusion, we established a progressive rat model of α-synuclein pathology which monitors the deficit longitudinally using both the [ 18 F]FMT PET tracer and behavioral parameters, 2 features that have strong relevance for translational approaches., (Copyright © 2021. Published by Elsevier Inc.)

Objective: The cystine/glutamate antiporter system x c - could represent a new target for antiepileptogenic treatments due to its crucial roles in glutamate homeostasis and neuroinflammation. To demonstrate this, we compared epilepsy development and seizure susceptibility in xCT knockout mice (xCT -/- ) and in littermate controls (xCT +/+ ) in different chronic models of epilepsy., Methods: Mice were surgically implanted with electrodes in the basolateral amygdala and chronically stimulated to develop self-sustained status epilepticus (SSSE); continuous video-electroencephalography monitoring was performed for 28 days after SE and hippocampal histopathology was assessed. Corneal kindling was induced by twice daily electrical stimulation at 6 Hz and maintenance of the fully kindled state was evaluated. Next, messenger RNA (mRNA) and protein levels of xCT and of the proteins involved in the phosphoinositide 3-kinase (PI3K)/Akt/glycogen synthase kinase 3β (GSK-3β)/eukaryotic initiation factor 2α (eIF2α)/activating transcription factor 4 (ATF4) signaling pathway were measured at different time points during epileptogenesis in NMRI mice treated with pilocarpine. Finally, the anticonvulsant effect of sulfasalazine (SAS), a nonselective system x c - inhibitor, was assessed against 6 Hz-evoked seizures in pilocarpine-treated mice., Results: In the SSSE model, xCT -/- mice displayed a significant delayed epileptogenesis, a reduced number of spontaneous recurrent seizures, and less pronounced astrocytic and microglial activation. Moreover, xCT -/- mice showed reduced seizure severity during 6 Hz kindling development and a lower incidence of generalized seizures during the maintenance of the fully kindled state. In pilocarpine-treated mice, protein levels of the PI3K/Akt/GSK-3β/eIF2α/ATF4 pathway were increased during the chronic phase of the model, consistent with previous findings in the hippocampus of patients with epilepsy. Finally, repeated administration of SAS protected pilocarpine-treated mice against acute 6 Hz seizure induction, in contrast to sham controls, in which system x c - is not activated., Significance: Inhibition of system x c - could be an attractive target for the development of new therapies with a potential for disease modification in epilepsy., (© 2019 UCB Pharma SA. Epilepsia published by Wiley Periodicals, Inc. on behalf of International League Against Epilepsy.)

Background/aims: To this date, the only available drugs for treating Alzheimer's disease are cognitive enhancers, which may improve the cognitive function of patients for a few years while the disease continues to progress. As such, there are intense investigations to develop disease-modifying drugs to suppress progressive neurodegeneration., Methods: In this study, a range of procognitive compounds are tested in a primary neuronal culture to determine their relative potential for promoting neuritogenesis., Results: We report that donepezil, memantine, dimebon, Pre-084 and 4-IBP are neuritogenic while tacrine, rosemarinic acid, memoquin and a BACE1 inhibitor suppress neurite outgrowth of neurons., Conclusions: The results of this study indicate that some procognitive compounds may possess a disease-modifying potential., (© 2015 S. Karger AG, Basel.)

The amount of marine debris in the environment is increasing worldwide, which results in an array of negative effects to biota. This study provides the first account of macrodebris on the beach and microplastics in the sediment (shoreline and infralittoral) in relation to tourism activities in Slovenia. The study assessed the quality and quantity of macrodebris and the quality, size and quantity of microplastics at six beaches, contrasting those under the influences of tourism and those that were not. Beach cleanliness was estimated using the Clean Coast Index. Tourism did not seem to have an effect on macrodebris or microplastic quantity at beaches. Over 64% of macrodebris was plastic, and microplastics were ubiquitous, which calls for classification of plastics as hazardous materials. Standard measures for marine debris assessment are needed, especially in the form of an all-encompassing debris index. Recommendations for future assessments are provided for the Adriatic region., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Synaptic vesicle 2 proteins (SV2), SV2A, SV2B and SV2C, are integral proteins localized on the surface of synaptic vesicles in all neurons. SV2 proteins appear to play an important, but not yet fully understood role in synaptic vesicle exocytosis and neurotransmitter release. Moreover, SV2 seems to be the receptor of the botulinum neurotoxin A. In the present study, using single and double-labeling fluorescent immunohistochemistry and in situ hybridization we have identified the brain pattern of SV2C mRNA and protein expression in mice. Our results indicated that SV2C protein was expressed in a small subset of brain regions including the olfactory bulb, olfactory tubercle, nucleus accumbens, caudate-putamen, ventral pallidum, globus pallidus, substantia nigra and the ventral tegmental area. These results were confirmed by means of in situ hybridization, except for the globus pallidus and the substantia nigra pars reticulata, in which no labeling was found, suggesting that SV2C-positive fibers in these areas are terminals of striatal projecting neurons. In the striatum, we found that, in addition to its presence in the projection neurons, SV2C was densely expressed in a fraction (around 45%) of cholinergic interneurons. In addition, our data also showed that SV2C was densely expressed in most dopaminergic neurons in the substantia nigra pars compacta and the ventral tegmental area (more than 70% of the dopaminergic neurons analyzed were SV2C-positive). Altogether, our results suggest that SV2C may contribute to the regulation of neurotransmitter release and synaptic transmission in the basal ganglia including cholinergic striatal interneurons and nigro-striatal/mesolimbic dopamine neurons., (Copyright © 2010 Elsevier B.V. All rights reserved.)

We investigated the long-term effects of sand extraction activities on the nematode communities from the Kwintebank. Although changes in nematode community composition cannot be completely uncoupled from natural processes, we suggest that the morphological changes in the sandbank and physical disturbance associated with the dredging activities indeed affected nematode community composition. Nematode diversity did not change since the start of the extraction activities but nematode community composition changed significantly. The SIMPER routine identified predatory nematodes to be important for the within group similarity at the start of the exploitation, while similarity in 1997 and 2001 was determined by the contribution of deposit feeding nematodes. In addition, long nematodes, vulnerable to physical disturbance became less important. These changes are attributed to long term changes in sediment characteristics in combination with additional short-term disturbances by the creation and filling of dredge furrows which are related to the extraction activities.

Species of the order Mysida (Crustacea, Peracarida) are shrimp-like animals that occur in vast numbers in coastal regions of the world. The order Mysida comprises 1,053 species and 165 genera. The present study covers 25 species of the well-defined Mysidae, the most speciose family within the order Mysida. 18S rRNA sequence analysis confirms that the subfamily Siriellinae is monophyletic. On the other hand the subfamily Gastrosaccinae is paraphyletic and the subfamily Mysinae, represented in this study by the tribes Mysini and Leptomysini, consistently resolves into three independent clades, and hence is clearly not monophyletic. The tribe Mysini is not monophyletic either, and forms two clades of which one appears to be closely related to the Leptomysini. Our results are concordant with a number of morphological differences urging a taxonomic revision of the Mysidae.

Of the information items that must be easily available to the different actors involved in the care process, radiological images are not the least important. While until recently it was not feasible to include these into the medical information system, this situation has changed. Still, emphasis in PACS (Picture Archiving and Communication Systems) is primarily on the technological aspects. In this paper, in contrast, we stress the importance of integration of images into the overall workflow and into the overall medical record. We do so using illustrations from the PACS project of the University Hospitals Leuven. We briefly indicate that tight integration at the user interface level is needed, and that this requires more than standardized communication between subsystems.

The assessment of the dose-image quality relation using storage phosphor systems requires a series of tasks. In the text, the main aspects are summarized and the differences with the measurements for X ray equipment using film-screen cassettes are indicated. Standards of testing are becoming available for quality control measurements of the equipment. The global analysis is, however, less standardised. Large scale trials concerning dose and image quality are missing. In particular, guidelines about the appropriate use of post processing parameters and image visualisation are scarce. In this regard, a newly proposed method to evaluate image quality as a function of post-processing parameters for particular types of clinical images is mentioned. It is concluded that a thorough analysis may be very time consuming, but if the properties of the digital detectors are exploited, many tasks can be automated.

From May 1997 to April 98, 30 radiological centers made an agreement with the Leuvens Universitair Centrum voor Kankerpreventie (LUCK) for the work out of physical and technical quality control in mammography screening. A protocol was used based on the European Guidelines for Quality Assurance. The reports of all 30 acceptance tests were retrospectively reviewed. The following parts showed to be most critical: alignment of radiation field and film in the bucky, tube voltage precision, automatic exposure controller, average optical density of a standard exposure, dark room and its safe lights. The mean film gradient was in the majority of the centers higher than what is prescribed in the European document. This is acceptable and even desirable whenever daily quality control shows that the development system is sufficiently stable. Although it is difficult to compare the scores for the specific tests with results in other countries, there is evidence that the tendencies are very similar.