bluuebunny/crossref_metadata_2025 huggingface dataset:
The genesis of epileptogenic cerebral heterotopia: clues from experimental models
Authors: Battaglia Giorgio , Bassanini Stefania , Granata Tiziana , Setola Veronica , Giavazzi Alessio , Pagliardini Silvia
Published: March 2024

The pre‐natal administration of methylazoxymethanol acetate (MAM) in rats is able to induce cerebral heterotopia that share striking similarities with those observed in human periventricular nodular heterotopia, a cerebral dysgenesis frequently associated with drug‐resistant focal seizures. In the present study, we investigated the mode of neurogenesis in cerebral heterotopia of MAM‐treated rats, by analyzing post‐natal cytoarchitectural features and time of neurogenesis using bromodeoxyuridine immunocytochemistry. The cytoarchitectural analysis demonstrated the existence, in the early post‐natal period, of white matter cellular bands in close anatomical relationship with the heterotopia, which most likely serve as a reservoir of young, migrating neurons for the newly forming heterotopia. The birth dating analysis demonstrated that the period of generation of neurons within the heterotopia and adjacent white matter bands, was extended in comparison to corticogenesis in normal rat brains. In addition, it demonstrated that the heterotopia were formed through a rather precise outside‐in (for cortical and periventricular heterotopia) and dorso‐ventral (for intra‐hippocampal heterotopia) neurogenetic pattern. We hypothesize that the MAM‐induced ablation of an early wave of cortical neurons is sufficient to alter
per se
the migration and differentiation of subsequently generated neurons, which in turn set the base for the formation of the different types of heterotopia. On this basis, we suggest a neurogenetic scheme for MAM‐induced heterotopia that can also explain the origin and intrinsic epileptogenicity of periventricular nodular heterotopia in humans.
Continuous giggling and autistic disorder associated with hypothalamic hamartoma
Authors: Pérez‐Jiménez Angeles , Villarejo Fransisco J , del Castillo María Concepción Fournier , García‐Peñas Juan José , Carreño Mar
Published: March 2024

We present the case of a child affected since early infancy from recurring episodes of giggling mixed with stereotypical behaviours, mingled with head drops, and eventually with falls, in the context of an autistic disorder. Scalp video‐EEG recordings revealed an epileptic encephalopathy with generalized slow spike‐and‐wave complexes alternating with electrodecremental periods, which generally corresponded to the onset of the aforementioned clinical sequences. A resection of a hypothalamic hamartoma was achieved at the age of two. Since then, after 22 months of follow‐up, the child is totally free from the giggling and the drops, and the autistic behaviour significantly improved during the second year of follow‐up. This case illustrates the difficulties to recognize some subtle ictal manifestations during infancy and childhood, and encourages the early surgical treatment of hypothalamic hamartomas when associated with epileptic encephalopathy and when technically possible. [Published with videosequences.]
Epilepsy and malformations of the cerebral cortex
Authors: Guerrini Renzo , Sicca Federico , Parmeggiani Lucio
Published: March 2024

Malformations of the cerebral cortex (MCC) are often associated with severe epilepsy and developmental delay. About 40% of drug‐resistant epilepsies are caused by MCC. Classification of MCC is based on embryological brain development, recognising forms that result from faulty neuronal proliferation, neuronal migration and cortical organisation. Hemimegalencephaly, an enlarged dysplastic hemisphere, can present as early onset severe epileptic encephalopathy or as partial epilepsy. In focal cortical dysplasia (FCD), MRI shows focal cortical thickening and simplified gyration. Patients have drug‐resistant, often early onset epilepsy. Complete surgical ablation of FCD is accompanied by remission in up to 90% of patients, but may be technically difficult. Tuberous sclerosis (TS) is a multisystemic disorder primarily involving the nervous system; 60% of patients having epilepsy, with 50% having infantile spasms. TS is caused by mutations in the
TSC1
and
TSC2
genes; 75% of cases are sporadic.
TSC1
mutations cause a milder disease. Bilateral periventricular nodular heterotopia (BPNH) consists of confluent and symmetric nodules of grey matter along the lateral ventricles. X‐linked BPNH presents with epilepsy in females and prenatal lethality in most males. Most patients have partial epilepsy.
Filamin A
mutations have been reported in families and sporadic patients. Lissencephaly (LIS – smooth brain) is a severe MCC characterised by absent or decreased convolutions. Classical LIS is quite rare and manifests with severe developmental delay, spastic quadriparesis and severe epilepsy.
XLIS
mutations cause classical lissencephaly in hemizygous males and subcortical band heterotopia in heterozygous females. Thickness of heterotopic band and degree of pachygyria correlate well with phenotype severity. Schizencephaly (cleft brain) has a wide anatomo‐clinical spectrum, including partial epilepsy in most patients. Polymicrogyria (excessive number of small and prominent convolutions) has a wide spectrum of clinical manifestations ranging from early onset epileptic encephalopathy to selective impairment of cognitive functions. Bilateral perisylvian polymicrogyria may be familial. Patients present with faciopharingo‐glosso‐masticatory diplegia and epilepsy, which is severe in about 65% of patients.
Split‐screen synchronized display. A useful video‐EEG technique for studying paroxysmal phenomena
Authors: Tinuper Paolo , Grassi Carlo , Bisulli Francesca , Provini Federica , Plazzi Giuseppe , Zoni Elena , Lugaresi Elio
Published: March 2024

Video‐EEG is an indispensable and widely used technique for studying paroxysmal phenomena. We present a method of processing video recordings to compare the sequence of ictal manifestations of different episodes. Five presentations of two seizures recorded in each of five patients are shown, in which apparently different ictal features are strongly superimposed and stereotyped. Split‐screen synchronized display is a simple and valid technique for studying and presenting particular semeiological aspects of epileptic seizures. (Published with videosequences)
Sandifer syndrome misdiagnosed as refractory partial seizures in an adult
Authors: Somjit Sriudomkajorn , Lee Yong , Berkovic Samuel F , Harvey A. Simon
Published: March 2024

We report a 27 year‐old man with intellectual disability and no prior history of seizures who presented with episodes of abdominal pain, head/eye version and unresponsiveness that were misdiagnosed and treated as partial seizures. Associated vomiting and haematemesis led to the correct diagnosis and treatment of reflux oesophagitis. The episodes immediately resolved and a diagnosis of Sandifer syndrome was made. This is only the second report of Sandifer syndrome in adult, a movement disorder of unknown mechanism that occurs almost exclusively in young children, often misdiagnosed as epilepsy or episodic dystonia. (Published with videosequences)
A critical review of the different conceptual hypotheses framing human focal epilepsy
Authors: Nair Dileep R. , Mohamed Armin , Burgess Richard , Lüders Hans
Published: March 2024

In the attempt to understand the processes affecting human focal epilepsy, various models that have been proposed as a back drop to which current observations of the clinical manifestations and therapies in this disorder can be tested. There are three main models that are reviewed. The notion of epileptogenicity as described by Penfield and Jasper's epileptogenic zone model postulates that specific regions of cerebral cortex have varying degrees of importance in the generation of focal epilepsy. A variation of this hypothesis comprises the second model put forth by Talairach and Bancaud. In this view the notion of the epileptogenic zone is expanded to incorporate a larger regions of cerebral cortex involved in the seizure propagation. A third concept and more separate hypothesis suggests that all components of the neural network involved in focal epilepsy are equally importance in the initiation and maintenance of the seizure. The various concepts underlying these models are reviewed in this paper and data from clinical and neurophysiologic observations are discussed in the context of these models. We suggest in this paper that the data best supports the epileptogenic zone hypothesis put forth by Penfield and Jasper.
Temporal lobe dysembryoplastic neuroepithelial tumour: significance of discordant interictal spikes
Authors: Labate Angelo , Briellmann Regula S. , Harvey Anthony S. , Berkovic Samuel F. , Federico Paolo , Kalnins Renate M. , Fabinyi Gavin C. , Jackson Graeme D.
Published: March 2024

Purpose:

Dysembryoplastic neuroepithelial tumours (DNET) are an important cause of refractory partial epilepsies. They usually occur within dysplastic cortex and tend to affect the temporal lobes. The EEG of these patients is characterised by slowing and/or epileptiform abnormalities with a multifocal distribution. We studied the EEG features of epilepsy patients with a temporal lobe DNET to assess the relationship of EEG abnormalities with the localisation of the tumour and the clinical features.

Methods

We retrospectively reviewed 16 patients with unilateral, temporal lobe DNET on MRI. The EEG abnormalities were classified as concordant to the lesion when the EEG discharges were confined to the ipsilateral temporal lobe or discordant when EEG discharges were found in other areas. Clinical and epilepsy characteristics were compared between patients with concordant and discordant EEG.

Results

Focal EEG abnormalities were found in 81% of the patients; 6/16 patients had concordant EEG abnormalities, and 7/16 patients had discordant EEG abnormalities. Epilepsy severity prior to the operation, antecedents and post‐operative outcome were not different between patients with concordant or discordant EEG abnormalities.

Conclusion

Patients with temporal lobe DNET often show EEG discharges discordant to the tumour. However, they do not appear to predict the clinical and epilepsy characteristics of these patients.
Ictal and interictal perfusion variations measured by SISCOM analysis in typical childhood absence seizures
Authors: Nehlig Astrid , Valenti Maria‐Paola , Thiriaux Anne , Hirsch Edouard , Marescaux Christian , Namer Izzie J.
Published: March 2024

Single photon emission computed tomography (SPECT) is currently used in the presurgical evaluation of medically intractable partial epilepsies, but not very often, in generalized epilepsy. In the present study, we used the SISCOM procedure, which represents the fusion of MRI and ictal‐interictal difference SPECT images using
99m
Tc‐ECD, to study cerebral blood flow changes during the ictal and postictal phases of typical childhood absence seizures. The study was performed on four children with typical, difficult to treat absence seizures, aged 10‐13 years at the time of scan. The delay between the onset of absence seizures and the injection of
99m
Tc‐ECD was carefully noted. One scan was performed during the ictal phase and showed diffuse blood flow decreases, while the three other scans performed during the postictal phase, showed generalized blood flow increase. These data are consistent with most previous data reporting generalized changes in functional activity, not limited to the thalamo‐cortical circuit in which absence seizures originate, and a decrease in cerebral blood flow during the ictal phase. Our data are concordant with the hypothesis that neuronal activity underlying the occurrence of spike‐and‐wave discharges does not seem to require an increase in metabolic demand and blood flow rates. [Published with videosequences]
Chess‐playing epilepsy: a case report with video‐EEG and back averaging
Authors: Mann M.W. , Gueguen B. , Guillou S. , Debrand E. , Soufflet C.
Published: March 2024

A patient suffering from juvenile myoclonic epilepsy experienced myoclonic jerks, fairly regularly, while playing chess. The myoclonus appeared particularly when he had to plan his strategy, to choose between two solutions or while raising the arm to move a chess figure. Video‐EEG‐polygraphy was performed, with back averaging of the myoclonus registered during a chess match and during neuropsychological testing with Kohs cubes. The EEG spike wave complexes were localised in the fronto‐central region. [Published with video sequences]
Épilepsie et sclérose en plaques
Authors: Lebrun Christine
Published: March 2024

L'épilepsie est trois à six fois plus fréquente chez les patients atteints de sclérose en plaques que dans la population générale. Le substratum anatomique des crises repose sur la présence de lésions de démyélinisation corticales et juxta‐corticales. Les crises partielles avec ou sans généralisation secondaire sont les plus fréquentes. Elles peuvent être prévalentes, survenir pendant les poussées, ou beaucoup plus tard dans une évolution progressive secondaire. Il n'existe actuellement pas de consensus pour la prise en charge de ces épilepsies, et les recommandations publiées ne présentent aucune particularité comparées aux autres épilepsies symptomatiques. Les phénomènes paroxystiques non‐épileptiques représentent le principal diagnostic différentiel ; ils répondent généralement bien aux molécules anti‐épileptiques à plus faibles doses.
Wall‐eyed bilateral internuclear ophtalmoplegia presenting as monocular alternating nystagmus: a non‐epileptic phenomenon in a case of diffuse axonal injury
Authors: Ozer Feriha , Mutlu Aytul , Meral Hasan , Kansu Tulay , Carsancaklı Bedri
Published: March 2024

A 15‐year‐old male in a persistent vegetative state due to diffuse axonal injury presented with seizures and spontaneous alternating monocular nystagmus. The cranial MRI revealed diffuse axonal injury involving supratentorial and infratentorial structures, and the splenium of the corpus callosum. The monocular alternating nystagmus was thought to be independent of seizures and occurred as a result of diffuse axonal injury affecting the medial longitudinal fasciculus bilaterally. [Published with videosequences]
Gelastic seizures due to right temporal cortical dysplasia
Authors: Dericioglu Nese , Cataltepe Oguz , Tezel Gaye Guler , Saygi Serap
Published: March 2024

Gelastic seizures are an uncommon seizure type. They are most frequently observed in patients with hypothalamic hamartoma. Their association with other types of cerebral lesions is rare. Depending on the location of the lesion, gelastic seizures may or may not be accompanied by a subjective feeling of mirth. The pathophysiological mechanisms of this type of seizure are still undefined, and little is known about which pathways promote laughter and its emotional content, mirth. We present a young man with drug‐resistant, gelastic seizures due to focal cortical dysplasia of the right inferior temporal gyrus. The lesion was evident on cranial MRI. Interictal EEG displayed a right temporal focus, whereas ictal EEG was not informative. Ictal loss of consciousness precluded reporting of any possible emotional experience. The patient underwent surgical resection of the lesion and has been seizure‐free with antiepileptic medication for two years. Although various anatomical regions may elicit laughter, in view of the current literature it seems that the anterior cingulate region is involved in the motor aspects of laughter, while the basal temporal cortex is involved in the processing of mirth. The fact that the present case exhibited gelastic seizures stresses once more the importance of the baso‐lateral temporal cortex in the genesis of this type of seizures.
[Published with video sequences]
Tonic seizures in subacute sclerosing panencephalitis: a video‐illustration of two cases
Authors: Demirbilek Veysi , Benbir Gulcin , Cokar Ozlem , Yalcin Destina , Bulut Hicran , Dervent Aysin
Published: March 2024

Subacute sclerosing panencephalitis is a progressive disorder which also presents with various types of seizures, mainly myoclonic jerks, atonic attacks and tonic‐clonic seizures. We report two cases, documented by video‐EEG that during the course of the disease also presented with tonic seizures. The differential diagnosis of non‐epileptic paroxysmal events might prove to be a problem.
[Published with videosequences]
Late‐onset, “Gastaut Type”, childhood occipital epilepsy: an unusual evolution
Authors: Caraballo Roberto Horacio , Cersósimo Ricardo Oscar , Fejerman Natalio
Published: March 2024

We report on two girls and one boy with clinical and electroencephalographic features of late‐onset childhood epilepsy with occipital paroxysms of the “Gastaut type”, showing an unusual evolution. Neurological examination and brain imaging were normal in all three. At the age of 7.5 years, eight years and ten years respectively, the three children presented with episodes of visual symptoms when awake, and in one of them, the seizures were occasionally followed by oculocephalic deviation. The interictal EEG showed bilateral occipital spike‐wave activated by eye closing. In two patients, the occipital seizures had been immediately followed by typical absences, since onset; in the other patient, five months after onset. The ictal EEG showed irregular bilateral occipital spike‐wave discharges during the visual symptoms, followed by generalized spike‐wave activity during the typical absences. The typical absences were activated by hyperventilation; the EEG did not show continuous spikes and waves during slow sleep. These three patients, with typical electroclinical features of “Gastaut type”, childhood occipital epilepsy, demonstrated an evolution which, to our knowledge, has not been previously described. We investigated whether this unusual, age‐dependent evolution was due to secondary bilateral synchrony or if these electroclinical features represent two types of idiopathic epileptic syndromes in the same patients.
The impact of epilepsy surgery on mortality
Authors: Ryvlin Philippe , Montavont Alexandra , Kahane Philippe
Published: March 2024

Patients with refractory epilepsy suffer from an increased risk of death, primarily due to seizure‐related fatalities including sudden unexpected death (SUDEP), which could be conceivably avoided by surgical cure of the epilepsy. Several series have addressed this issue by comparing the mortality rate between medically and surgically treated drug resistant populations, as well as between patients, seizure free and non seizure free post‐operatively. Results from some studies suggest that successful temporal lobe surgery reduced the risk of death to that observed in the normal population, whereas patients who continue to suffer recurrent seizures still present an increased standardized mortality ratio (SMR). However, other series have failed to replicate this finding, or found no difference in the overall mortality and SUDEP rates between operated and medically treated patients. All the above studies suffer various types of methodological limitations, hampering any definite conclusion regarding the impact of epilepsy surgery on mortality. However, part of the apparently discordant reported findings might be reconciled through the following framework. Patients who will eventually respond favourably or unfavourably to an anterior temporal lobectomy might already differ in the risk of seizure‐related death, pre‐operatively. Specifically, patients whose temporal lobe epileptogenic network extends to the perisylvian region (temporal plus epilepsy) appear to be at higher risk of failed TLE surgery, secondary generalised tonic‐clonic seizures, ictal apnoea or insula‐driven severe cardiac arrhytmias. This population might carry most of the SUDEP burden, both pre‐ and post‐operatively, accounting for the lack of an obvious net reduction of seizure related deaths after temporal lobe surgery. A multicentric study has recently been launched in order to test this hypothesis, and will hopefully help to conclude on the impact of epilepsy surgery on mortality outcome.
Descriptions of clinical semiology of seizures in literature
Authors: Wolf Peter
Published: March 2024

Literary texts are an important part of the cultural history of many fields of medicine. Accounts of epilepsy are frequent, and descriptions of seizure semiology are often included with varying detail. This review looks at these, and considers the authors' background knowledge of epilepsy. The first group of writers suffered seizures themselves. Some of them provide remarkable and novel insights into the subjective symptoms and experiences in and around seizures.

A second group draws from their own observations of seizures in others who may have been close relatives or fortuitous strangers. Here, the outside view prevails, and seizures may be described with clinical objectiveness. Commonly, the reactions of onlookers become part of the narrative beyond the seizure description.

The third group writes from second‐hand knowledge, which may be other observer reports, interviews with people with epilepsy or with experts, information being available in dictionaries, medical textbooks and the like. The professional standard of most writers means that the resulting descriptions are quite accurate, but there are also examples of poor use of such information. Many authors' sources are not known, but can be assumed to belong to one of the above categories, and we can sometimes guess. It appears that even authors with no first‐hand knowledge are often aware of seizure types other than the most widely known, generalised tonic‐clonic, and there is a widespread interest in warnings and how the afflicted respond to them.

The quality of an author's fictional account of epilepsy should not be judged from a translation, because specific aspects and the language involved in the description may have been misunderstood by the translator.
Isolated paroxysmal arousals as focal epilepsy
Authors: Valenti Maria Paola , Froelich Sébastien , Rudolf Gabrielle , Thibault Anne , Chassagnon Serge , Arzimanoglou Alexis , Hirsch Edouard
Published: March 2024

Paroxysmal motor phenomena and arousals during sleep are frequent. The differential diagnoses between benign hypnic transient events, epileptic and non‐epileptic seizures represent a common clinical problem. Video‐EEG monitoring during sleep, recording several episodes in the same patient, is essential in order to characterize these phenomena. It offers the possibility to compare electro‐clinical data, to demonstrate the eventual stereotyped pattern of motor phenomena and their progression in time, and to study EEG‐polygraphic correlates. The recently described double split‐screen synchronized display (DSSSD) technique represents a useful tool for comparing particular clinical patterns of epileptic seizures when dealing with complex, hypermotor phenomena observed in frontal lobe epilepsy. We reviewed the data of 24 patients admitted during a two‐year period (2002‐2003) to our epilepsy sleep unit for isolated paroxysmal sleep motor events. Four patients presented with very brief paroxysmal arousals without daytime fits. Three of our patients presented isolated paroxysmal arousals, whereas in one, the events were associated with hypermotor seizures. We present a simplified variant of the DSSSD method (modified DSSSD) that can be used to study episodes of paroxysmal arousals in order to confirm their stereotyped motor pattern. The clinical aspects and the EEG‐polygraphy patterns were informative, with the absence of asymmetrical tonic or dystonic posturing of the limbs. Scalp EEG alone does not usually provide much information in patients with isolated paroxysmal arousals. Coupled to the modified DSSSD technique, it may allow confirmation of the diagnosis of frontal epilepsy, as was the case in our four patients.
[Published with video sequences]
“Burst and slow complexes” in nonconvulsive epileptic status
Authors: Ikeda Akio , Matsui Masaru , Hase Yoshiki , Hitomi Takehumi , Takahashi Yukitoshi , Shibasaki Hiroshi , Shimohama Shun
Published: March 2024

Generalized 1Hz, burst‐and‐slow‐wave complexes were observed in a comatosed patient with acute disseminated encephalomyelitis (ADEM) when she showed extremely intractable, generalized convulsions and fragmented myoclonus in the whole body. Two types of short‐latency SEPs were obtained separately during the burst and slow phase of the EEG (SEP‐burst and SEP‐slow, respectively), which showed a two fold greater amplitude of N20 in the former than in the latter. This suggests enhanced responsiveness to the peripheral stimuli during the burst phase as compared with the slow phase. CSF and serum were positive for autoantibodies to NMDA receptors. The “burst and slow complexes” reported here are considered to be an atypical EEG pattern of a generalized epileptic phenomenon.
Lingual epilepsia partialis continua in Rasmussen's encephalitis
Authors: Nayak Dinesh , Abraham Mathew , Kesavadas Chandrasekharan , Radhakrishnan Kurupath
Published: March 2024

We report an adult male who presented with disabling dysarthria due to epilepsia partialis continua (EPC) of the left half of the tongue. The clinical, brain magnetic resonance imaging and electroencephalographic features were consistent with Rasmussen's encephalitis, although, despite having had the disease for over 15 years, he did not exhibit any hemiparesis. The accompanying video illustrates the lingual EPC and its total resolution following a right frontal opercular focal cortical resection.

[Published with video sequences]
.
Senile myoclonic epilepsy in Down syndrome: a video and EEG presentation of two cases
Authors: De Simone Roberto , Daquin Géraldine , Genton Pierre
Published: March 2024

Myoclonic epilepsy is being increasingly recognized as a late‐onset complication in middle‐aged or elderly patients with Down syndrome, in association with cognitive decline. We show video and EEG recordings of two patients, both aged 56 years, diagnosed with this condition. At onset, myoclonic epilepsy in elderly DS patients may resemble, in its clinical expression, the classical juvenile myoclonic epilepsy with the characteristic occurrence of jerks on awakening. It is clearly associated with an Alzheimer‐type dementia, and may also occur in non‐DS patients with Alzheimer's disease: hence the possible denomination of “senile myoclonic epilepsy”.

[Published with video sequences]
Epilepsy and multiple sclerosis
Authors: Lebrun Christine
Published: March 2024

Epilepsy is three to six times more frequent in multiple sclerosis than in the general adult population. The probable anatomic basis for the seizures is areas of inflammation and demyelination in the cortex and juxtacortical white matter. Partial epilepsies with focal seizures often with atypical symptoms and with or without secondary generalisation are the usual pattern. Seizures can be observed as the first symptom of multiple sclerosis, or during relapses, with a direct correlation between paroxysmal phenomena and plaques demonstrated by brain MRI. Infrequently, it can start during the progressive phase, without active inflammation, generally associated with brain atrophy and high lesion load. Generally, the prognosis of epilepsy in multiple sclerosis patients is estimated to be good, without special recommendations or consensus for the choice of anti‐epileptic drug. Non‐epileptic paroxysmal symptoms may be confused with epileptic seizures. It usually responds to many different antiepileptic drugs.
Epilepsy and alcohol
Authors: Bartolomei Fabrice
Published: March 2024

While the links between alcoholism and epilepsy are well demonstrated, the classification of alcohol related seizures is still controversial. The best recognized seizures are the “alcohol withdrawal seizures” (AWS). However, experimental and clinical data strongly suggest that withdrawal is not the only mechanism by which the chronic absorption of alcohol may act. Specific epileptogenesis may underlie seizures unrelated to withdrawal (SUW). Epileptogenesis in this context involves several mechanisms including alterations of excitation/inhibition systems and a kindling‐like effect. A classification scheme was proposed in which patients presenting with seizures unrelated to any cause other than alcohol are classified in several successive stages of “alcoholic epilepsy”, the first being characterized by AWS, the second by SUW and the last by persistent chronic seizures.
Anticonvulsant effects of N
6
‐cyclohexyladenosine microinjected into the CA1 region of the hippocampus on entorhinal cortex‐kindled seizures in rats
Authors: Heidarianpour Ali , Sadeghian Efat , Mirnajafi‐Zadeh Javad , Fathollahi Yaghoub , Mohammad‐Zadeh Mohammad
Published: March 2024

In this study, the role of adenosine A1 receptors of the hippocampal CA1 region in entorhinal cortex‐kindled seizures was investigated in rats. Animals were kindled by daily electrical stimulation of the entorhinal cortex. In fully kindled rats, N
6
‐cyclohexyladenosine (CHA; a selective A1 receptor agonist) and 1, 3‐dimethyl‐8‐cyclopenthylxanthine (CPT; a selective A1 receptor antagonist) were microinfused bilaterally into the hippocampal CA1 region. Rats were stimulated and seizure parameters were measured. Results obtained showed that CHA (10 and 50 μ moles) decreased the afterdischarge duration (ADD) in the hippocampal CA1 region and entorhinal cortex, stage 5 seizure duration (S5D) and seizure duration (SD) only at the dose of 50 μ moles, and significantly increased the latency to stage 4 (S4L). Intrahippocampal CPT increased ADD and S5D, and significantly reduced the latency to stage 4 (S4L) at the dose of 10 lmoles. Pretreatment of rats with CPT (5 μ moles) before CHA (50 μ moles), significantly reduced the effect of CHA on seizure parameters. The results suggest that the CA1 region of the hippocampus plays an important role in spreading seizure spikes from the entorhinal cortex to other brain regions and activation of adenosine A1 receptors in this region participates in the anticonvulsant effects of adenosine agonists.
Advantages and Challenges of Biobased Plastics: A Qualitative Analysis of Stakeholders’ Perceptions
Authors: Başar Enes Emre , Kes- Erkul Aysu
Published: March 2024

The circular economy mostly relies on the reduction of fossil-based materials.
Finding economically viable, low-cost, renewable, and biodegradable alternatives to
plastic packaging is a significant challenge for this aim since it is widely used in the
daily consumption of various products. Bioplastics are already considered promising
substitutes for packaging materials since they are biodegradable, use renewable resources,
and release fewer greenhouse gases. However, the shift from fossil-based to biobased
materials also has its difficulties. This study uses qualitative data collected from three
primary stakeholder groups of this transition, namely, R&D managers from the packaging
industry, researchers, and policymakers. The research findings show that stakeholders
are mostly in consensus regarding the advantages and challenges of the shift from fossilbased
plastic to bioplastics. The knowledge and awareness of the process are highly
compatible with the literature on the subject. Additionally, the findings suggest that although bioplastics have the potential to contribute significantly to sustainability goals
and the circular economy greatly costs, lack of regulations, incentives and inadequate
recycling infrastructure are major obstacles to change. The agreement of stakeholders on
the matter of challenges also reveals the need for common ground for a solution.
Sharnie
Authors: LONG RACHEL
Published: March 2024

Rachel Long’s debut collection, My Darling from the Lions (Picador 2020 / Tin House 2021) was shortlisted for the Forward Prize for Best First Collection, The Costa Book Award, The Rathbones Folio Prize, and The Sunday Times Young Writer of the Year Award. The US edition featured in the New York Times Book Review, and was named one of the 100 must-read books of 2021 by TIME.  An earlier version of this poem was published in The Poetry Review, Vol. 112, No. 3, Autumn 2022
Tubular Cellulose Composite as a Vehicle for the Development of Meat Products with Low Nitrite Content
Authors: Panitsa Athanasia , Petsi Theano , Kanellaki Maria , Koutinas Athanasios A. , Kandylis Panagiotis
Published: March 2024

Research background. Nitrite salts are among the most used preservatives in meat products as they ensure their safe consumption. Despite their positive effects on food safety and stability, many side effects on human health have been reported, leading to the need to reduce their use. Therefore, the aim of this study is to produce veal products with low nitrite content through low diffusion of potassium nitrite and to study their microbiological characteristics.
Experimental approach. Edible tubular cellulose from leaf celery was produced and KNO2 was encapsulated in this material. This was achieved in two ways: by impregnation of tubular cellulose in a KNO2 solution under stirring and using starch gel as a stabilizer. Two samples of impregnated cellulose were applied on the surface of two veal samples of which one was stored at room temperature and the other at 3 °C. Similarly, two samples of cellulose with starch gel were applied on the surface of two veal samples of which one was stored at room temperature and the other at 3 °C. The KNO2 diffusion in different depths of the meat was measured and its effect on the microbiological characteristics of the meat was evaluated. Τhe experiment was carried out in duplicate.
Results and conclusions. A satisfactory percentage of about 70 % of the initially encapsulated amount of KNO2 was diffused in the meat, while the rest remained in the pores of the delignified leaf celery. The migrating amount of KNO2 proved to be effective in preserving meat, as the microbiological load decreased significantly (especially within the first 12 h, from a decrease of 0.6 log CFU/g up to 2.4 log CFU/g).
Novelty and scientific contribution. The demand for meat products with low nitrite content is constantly increasing and the results of the present study are promising for the development of this technology in scale-up systems and on an industrial scale. This innovative approach could lead to products with controlled diffusion of the preservatives.
Restoranlarda Yalnız Yemek Yiyen Müşterilerin Fiziksel ve Psikolojik Unsur Algılarının Davranışsal Niyetler Üzerine Etkisi
Authors: Apak Ömer Ceyhun
Published: March 2024

Bu araştırmanın amacı yalnız yemek yeme bağlamında restoran müşterileri perspektifinden restoranların fiziksel ve psikolojik unsurları arasındaki ilişkiyi belirlemek, fiziksel ve psikolojik unsurların yalnız yemek yiyen müşterilerin bölgesellik algılarını etkileyip etkilemediğini ortaya çıkarmak, bölgesellik algısının yalnız yemek yeme memnuniyeti ve tekrar ziyaret etme niyeti üzerine etkisini incelemek ve yalnız yemek yeme memnuniyeti ile tekrar ziyaret etme niyeti arasındaki ilişkiyi belirlemektir. Bu kapsamda Türkiye’nin tek haneli yaşayan nüfusunun en fazla olduğu Gümüşhane ilindeki yalnız yemek yiyen restoran müşterilerinden 399 veri toplanmıştır. Araştırma verileri sosyal ve davranış bilimlerinde yaygın olarak kullanılan yapısal eşitlik modellemesi kullanılarak test edilmiştir. Sonuç olarak fiziksel unsurlar ile psikolojik unsurlar arasında pozitif ilişki tespit edilmiştir. Fiziksel ve psikolojik unsurların bölgesellik algısı üzerinde pozitif etkisi bulunmuştur. Bununla birlikte bölgesellik algısının yalnız yemek yeme memnuniyeti ve restoranı tekrar ziyaret etme niyeti üzerinde etkili olduğu saptanmıştır. Ayrıca araştırma bulgularına göre yalnız yemek yeme memnuniyetinin restoranı tekrar ziyaret etme niyeti üzerinde etkisi bulunmaktadır.
Исследование режима высших гармоник в электрических сетях фанерного производства
Authors: Торопова Анна Константиновна , Черепанов Вячеслав Васильевич
Published: March 2024

Произведен анализ спектрального состава токов, генерируемых главным приводом лущильного станка, и разработано математическое описание параметров режима высших гармоник, протекающих по электрическим сетям заводов по производству фанеры. Для достижения поставленной цели впервые выполнены экспериментальные исследования на действующем фанерном предприятии Кировской области. Установлено, что в спектральном составе тока присутствуют канонические и анормальные гармоники, создаваемые выпрямителями, работающими с двигателями главного привода лущильных станков. Изменение высших гармоник тока, генерируемого выпрямителями, носит резкопеременный стохастический характер. Установлено, что процесс изменения токов высших гармоник в электрических сетях фанерных производств имеет стационарный характер. Получены статистические законы распределения токов высших гармоник (канонических) на интервале осреднения 200 мс и их числовые характеристики. Определены основные характеристики нагрузочных диаграмм лущильных станков. Предложено изменение высших гармоник во времени описывать решетчатыми моделями, интерполированными сплайн-функциями первой степени. Результаты статистического анализа спектрального состава токов и полученную математическую модель параметров режима высших гармоник рекомендовано использовать при решении ряда задач на стадии проектирования систем электроснабжения фанерных производств и для дальнейшей разработки методики расчетов параметров режима высших гармоник
О влиянии формы опорной поверхности броневого электромагнита на его динамическую тяговую характеристику
Authors: Большенко Ирина Александровна , Мартиросян Анна Гариковна , Батищев Денис Владимирович , Гречихин Валерий Викторович
Published: March 2024

Представлены результаты оценки влияния форм опорных поверхностей броневого электромагнита на его динамические тяговые характеристики. Проведен обзор технической литературы, связанной с исследованиями электромагнитов с ферромагнитными шунтами. Показана актуальность разработки электромагнитных приводов с регулируемой динамической тяговой характеристикой. Проведены исследования тяговых динамических характеристик электромагнита броневого типа с различными формами опорных поверхностей с использованием программных комплексов FEMM и OpenModelica. Сделаны выводы о влиянии формы опорной поверхности броневого электромагнита на его тяговую динамическую характеристику, которые могут помочь в выборе формы и размеров ферромагнитного шунта, соответствующих назначению и противодействующим усилиям электромагнитного механизма.
FİZİKSEL PARAMETRELERİN HİDROJEN PEM YAKIT HÜCRESİ PERFORMANSINA ETKİLERİ ÜZERİNE DEĞERLENDİRME
Authors: İlbeyoğlu Selman , Gürbüz Hüseyin
Published: March 2024

Geleneksel fosil yakıtlar, rezervlerinin sınırlı ve ciddi zararlı kirletici sorunlarının olması önemli problemdir. Fosil yakıtlara en önemli sürdürülebilir alternatif yakıt ve enerji kaynağı hidrojendir. Hidrojenin kimyasal enerjisinin elektrik enerjisine dönüştürüldüğü sistem olan direkt hidrojenli PEM yakıt hücresi umut vaat eden bir enerji kaynağıdır. Bu çalışmada PEM yakıt hücresinin bileşenlerinin ve bazı durumların PEM yakıt hücresi performansına etkisi irdelenmiştir. Öncelikle PEM yakıt hücresinin çalışma sistemi irdelendi. Yakıt hücresinin parçaları ve bu parçaların yakıt hücresi yığın maliyetine etkisi incelendi. Son olarak membran, gaz difüzyon tabakası, bipolar tabaka ve anot-katot elektrotlarının PEM yakıt hücresi performansına etkileri araştırıldı. PEM yakıt hücresinde membran kalınlığı azaldıkça performansının arttığı görüldü. Gaz difüzyon tabakasında az veya aşırı suyun, yakıt hücresi performansı sınırlayıcı etkisi tespit edildi. Grafit gibi elektrik iletkenliği iyi olan ve korozyona dayanıklı bipolar plakanın yakıt hücresi performansını artırdığı tespit edildi. Elektrotların elektrik iletkenliği ve hidrojenin elektrotların yüzeyine tutunma kabiliyeti artıkça performansı olumlu etkilediği görüldü.
THE EFFECT OF GRAPHITE ADDITION ON THE FRICTION COEFFICIENT AND WEAR BEHAVIOR OF GLASS FIBER REINFORCED COMPOSITES
Authors: Demir Mehmet Emin
Published: March 2024

The use of fillers in fiber-reinforced epoxy matrix composites to enhance the wear performance of the composite is a widely employed method nowadays. In this study, the effect of incorporating graphite filler into a glass fiber-reinforced composite structure on the tribological properties of the composite was investigated. Composite materials produced using the hand lay-up method with three different levels of graphite filler were compared to unfilled composites in terms of wear behavior under different loads (7 N, 10 N, 15 N) and sliding distances (200 m, 400 m). The influence of load, filler content, and sliding distance on the friction coefficient and wear rate was discussed. When the results are examined, the significant effects of graphite filler on wear volume and friction coefficient are clearly observed. In the composite containing 12% graphite, the wear volume has decreased by almost 96%; this ratio has been around 93% for the composite with 4% graphite filler. As the reinforcement of graphite and force increase, the friction coefficient decreases, whereas with the increase in sliding distance, the friction coefficient declines. Microstructural analysis revealed that the filled composites exhibited less abrasion compared to the unfilled composites, and the surface porosity and craters were shallower.
FOTOVOLTAİK VE BİYOGAZ ENERJİ SİSTEMLERİNİN ENERJİ VE ÇEVRESEL POTANSİYELLERİNİN İNCELENMESİ: SÜT SIĞIRI ÇİFTLİĞİ ÖRNEĞİ
Authors: Korkmaz Beyza , Hacısalihoğlu Saadet
Published: March 2024

Doğal kaynaklardan enerji kazanımları dünya genelinde yaygınlaşmaya başlamıştır. Günümüzde de sık duyduğumuz güneş ve biyogaz enerji sistemleri yatırımcıların da ilgisini çekmektedir. Uygun bölgede uygun yatırımlar ile büyük kazançlar elde edilmesi hem enerjiyi daha çevreci hem de yatırımcıyı daha karlı duruma getirmiştir. Bu çalışmada Bursa’nın Karacabey ilçesinde bir süt sığırı çiftliğine güneş veya biyogaz enerji sistemlerinin kurulumu için enerji ve çevresel açıdan potansiyelleri incelenerek iki enerji sistemleri arasında karşılaştırma yapılmıştır. Güneş enerji sistemi için RETScreen programı kullanılarak süt sığırı çiftliğinin toplamda 1.026.597 kWh/yıl’lık elektrik üreteceği ve sistemin toplamda 345 tCO2/yıl sera gazı emisyonu azaltılabileceği tespit edilmiştir. Biyogaz sistemi için 2023 yılının sonunda çiftlikten üretilecek toplam elektrik üretim potansiyeli 1.012.158 kWh/yıl olduğu ve toplamda 692,316 ton/yıl CO2 emisyonun engellenebileceği belirlenmiştir. Çiftliğin yıllık tüketilen elektrik enerjisi miktarının 885.855 kWh/yıl olduğu tespit edilmiştir. İki enerji sistemi ile de çiftliğin elektrik enerji miktarının karşılanacağı fakat biyogaz tesisinin sera gazı emisyonunu daha fazla engelleyeceği sonucuna varılmıştır. Ancak, biyogaz tesisinin ilk yatırım ve işletme maliyetlerinin fazla olması ve yıllara göre hayvan miktarlarında düşüşlere bağlı olarak atık miktarlarında azalmaların meydana gelmesi ve bu durumun tesisin verimliliğini olumsuz etkilemesi gibi durumlar nedeniyle süt sığırı çiftliğine güneş panellerinin kurulmasına karar verilmiştir.
Rest-Stickstoff-Elimination aus bereits gereinigtem Abwasser im Bypass - ein modifiziertes Verfahren mit Wirbelschwebebett-Technologie
Authors: Leonhard Stephan , Thoma Konrad , Schreff Dieter , Wichern Marc , Hilliges Rita
Published: March 2024

Für die Nachrüstung von Großkläranlagen mit erhöhten Stickstoffanforderungen wurde ein bewährtes Verfahren modifiziert. Die Rest-Stickstoff-Elimination erfolgt in einer nachgeschalteten Stufe und behandelt das bereits gereinigte Abwasser im Bypass mit Hilfe der Wirbelschwebebett-Technologie. Nitratstickstoff-Konzentrationen von 10 mg/l im Zulauf zur nachgeschalteten Stufe werden dabei um bis zu 90% eliminiert (= 1 - 2 mgNO3-N/L im Ablauf). Basierend auf dem vierjährigen Betrieb einer Pilotanlage und mehrerer Laboranlagen im halbtechnischen Maßstab wurde das Verfahren weiterentwickelt und getestet. Die vorliegende Studie befasst sich insbesondere mit dem Einfluss der hydraulischen Verweilzeit auf die gezielte Rest-Stickstoff-Elimination und deren Auswirkung auf die Rest-CSB-Konzentrationen im Ablauf. Die Ergebnisse liefern wichtige Erkenntnisse für die praktische Anwendung des modifizierten Verfahrens zur effizienten Abwasserreinigung und geben Hinweise für die Dimensionierung entsprechender Anlagen für den Einsatz im Ablauf großer Kläranlagen.
Agents and mechanisms of political domination, or how a “winning coalition” rules
Authors: Solovyov A.I.
Published: March 2024

Considering the relationship between state and society as the main area of thematic division of power “over” and “for”, the author shows the grounds that reveal that political domination is a certain form and stage of the historical evolution of political power, reflecting (in contrast to the democratic version of its development) the gradual usurpation by the ruling circles of their institutional (general civil) powers, truncation of citizens' rights and reduction of opportunities for their participation in government decision-making. In this context, the author, considering internal elite conflicts as the main source of such an evolution of power relations, draws attention to the so-called “winning” coalition of the ruling class, which concentrated in its hands the main instruments of control over government decision-making and the distribution of key public goods and resources. At the same time, a complex set of functions and tasks for developing public policy goals, identifying privileged groups and maintaining social stability predetermines the identification of internal groupings of this elite stratum, allowing it to manage and construct social relations in accordance with the stated political course and its hidden intentions. In this context, the article identifies seven main segments of this ruling group, performing various tasks in the field of competition with rival groups of the ruling class and in the field of relations with society and structures of the civil sector. In this regard, the corresponding contradictions between individual segments of the “winning” coalition are identified, as well as the technologies and mechanisms characteristic of these elite groups that contribute to the fulfillment of their role and support the format of political dominance.