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A reduced-cost explicitly correlated second-order Møller–Plesset (MP2-F12) approach is presented. Based on our recent reduced-cost explicitly correlated coupled-cluster method [J. Chem. Theory Comput., 19, 174 (2023)], the frozen natural orbital, the natural auxiliary basis, and the natural auxiliary function approximations are utilised to decrease the size of the molecular orbital basis and the auxiliary basis sets required for the density fitting and for the expansion of the explicitly correlated geminals. The necessary modifications of the above approximations for MP2-F12 are discussed. The performance of the new method is tested for atomisation and reaction energies. Our results demonstrate that speedups of 1.5–4 can be achieved in the calculation of MP2-F12 correlation energies with a moderate loss of accuracy. [ABSTRACT FROM AUTHOR]

Aim of study. Glutamate decarboxylase (GAD) enzyme can be a target intracellular antigen in autoimmune focal epilepsy. GAD65 antibody is in found patients diagnosed with drug-refractory temporal lobe epilepsy (TLE). We explore the clinical features of the disease and therapeutic options. Material and methods. We present the cases of four TLE patients, two of them with type 1 diabetes. All of them were drug- -resistant and therefore underwent presurgical evaluation, which revealed GAD65 antibody positivity. We discuss the four GAD65 antibody positive temporal lobe epilepsy patients' electroclinical data, the treatments, and their effectiveness. Results. One of them became seizure-free after right anterior temporal lobe resection, two of them did not show significant improvement with immunmodulatory agents, and the fourth patient with the shortest duration of disease had significant improvement in seizure status and normalisation of cognitive status with IVIg therapy. Conclusions and clinical implications. Our cases show that the earlier a GAD65 antibody is detected, the greater the chance of achieving seizure freedom or improvements in both seizure and cognitive status with immunomodulatory agents. However, in some cases, surgery may also bring seizure freedom, but with a risk of cognitive deterioration. [ABSTRACT FROM AUTHOR]

Background: Although COVID‐19 is primarily an acute respiratory infection, 5%–40% of patients develop late and prolonged symptoms with frequent neurological complaints, known as long COVID syndrome. The presentation of the disease suggests that COVID infection may cause functional and/or morphological central nervous system alterations, but studies published in the literature report contradictory findings. Purpose: To investigate the chronic effects of COVID‐19 on cerebral grey matter in a group of young patients without comorbidities, with mild course of COVID infection and no medical complaints at the time of examination. Study Type: Prospective. Population: Thirty‐eight young (age = 26.6 ± 5.0 years; male/female = 14/24), adult participants who recovered from mild COVID infection without a history of clinical long COVID and 37 healthy control subjects (age = 25.9 ± 2.8 years; male/female = 14/23). Field Strength/Sequence: Three Tesla, 3D T1‐weighted magnetization‐prepared rapid gradient‐echo, 2D T2‐weighted turbo spin‐echo. Assessment: MRI‐based morphometry and volumetry along with neuropsychological testing and self‐assessed questionnaire. Statistical Tests: Fisher's exact test, Mann–Whitney U‐test, and multiple linear regression analyses were used to assess differences between COVID and healthy control groups. P < 0.05 was used as cutoff for significance. Results: In the COVID group, significantly lower bilateral mean cortical thickness (left/right‐hemisphere: 2.51 ± 0.06 mm vs. 2.56 ± 0.07 mm, η2p = 0.102/2.50 ± 0.06 mm vs. 2.54 ± 0.07 mm, η2p = 0.101), lower subcortical gray matter (57881 ± 3998 mm3 vs. 60470 ± 5211 mm3, η2p = 0.100) and lower right olfactory bulb volume (52.28 ± 13.55 mm3 vs. 60.98 ± 15.8 mm3, η2p = 0.078) were found. In patients with moderate to severe anosmia, cortical thickness was significantly lower bilaterally, as compared to patients without olfactory function loss (left/right‐hemisphere: 2.50 ± 0.06 mm vs. 2.56 ± 0.05 mm, η2 = 0.173/2.49 ± 0.06 mm vs. 2.55 ± 0.05 mm, η2 = 0.189). Using further exploratory analysis, significantly reduced cortical thickness was detected locally in the right lateral orbitofrontal cortex in the COVID group (2.53 ± 0.10 mm vs. 2.60 ± 0.09 mm, η2p = 0.112). Data Conclusion: Even without any subjective or objective neurological complaints at the time of the MR scan, subjects in the COVID group showed gray matter alterations in cortical thickness and subcortical gray matter volume. Level of Evidence: 2 Technical Efficacy: Stage 3 [ABSTRACT FROM AUTHOR]

The adsorption of acetamide on low density amorphous (LDA) ice is investigated by grand canonical Monte Carlo computer simulations at the temperatures 50, 100, and 200 K, characteristic of certain domains of the interstellar medium (ISM). We found that the relative importance of the acetamide–acetamide H-bonds with respect to the acetamide–water ones increases with decreasing temperature. Thus, with decreasing temperature, the existence of the stable monolayer, characterizing the adsorption at 200 K, is gradually replaced by the occurrence of marked multilayer adsorption, preceding even the saturation of the first layer at 50 K. While isolated acetamide molecules prefer to lay parallel to the ice surface to maximize their H-bonding with the surface water molecules, this orientational preference undergoes a marked change upon saturation of the first layer due to increasing competition of the adsorbed molecules for H-bonds with water and to the possibility of their H-bond formation with each other. As a result, molecules stay preferentially perpendicular to the ice surface in the saturated monolayer. The chemical potential value corresponding to the point of condensation is found to decrease linearly with increasing temperature. We provide, in analogy with the Clausius–Clapeyron equation, a thermodynamic explanation of this behavior and estimate the molar entropy of condensed phase acetamide to be 34.0 J/mol K. For the surface concentration of the saturated monolayer, we obtain the value 9.1 ± 0.8 µmol/m2, while the heat of adsorption at infinitely low surface coverage is estimated to be −67.8 ± 3.0 kJ/mol. Our results indicate that the interstellar formation of peptide chains through acetamide molecules, occurring at the surface of LDA ice, might well be a plausible process in the cold (i.e., below 50 K) domains of the ISM; however, it is a rather unlikely scenario in its higher temperature (i.e., 100–200 K) domains. [ABSTRACT FROM AUTHOR]

A new approach is proposed to reduce the basis set incompleteness error of the triple excitation correction in explicitly correlated coupled-cluster singles and doubles with perturbative triples calculations. Our method is similar to the intuitive triples correction approach of Knizia et al. [J. Chem. Phys. 130, 054104 (2009)] but, in contrast to the latter, is size-consistent. The new approximation is easy to implement, and its overhead is negligible with respect to the conventional (T) correction. The performance of the approach is assessed for atomization, reaction, and interaction energies as well as for bond lengths and harmonic vibrational frequencies. The advantages of its size consistency are also demonstrated. [ABSTRACT FROM AUTHOR]

Background: Studies examining epilepsy as a COVID-related death risk have come to conflicting conclusions. Our aim was to assess the prevalence of epilepsy among COVID-related deaths in Hungary.Methods: Each COVID-19 infection case is required to be reported on a daily basis to the National Public Health Center of Hungary. This online report includes the beginning and end of the infection, as well as information on comorbidities. Death during infection is regarded as COVID-related. The anonymized data of each deceased patient are published on an information website (www.koronavirus.gov.hu) and provides up-to-date information on each patient with the date of death, the patient's sex, age, and chronic illness.Results: There were 11,968 patients who died of COVID-19 in Hungary between 13 March 2020 and 23 January 2021. Among 11,686 patients with no missing values for comorbidities, 255 patients had epilepsy (2.2%). Epilepsy was much more common among those who died at a young age: 9.3% of those who died under the age of 50 had epilepsy, compared with only 1.3% in those over the age of 80. The younger an age group was, the higher was the prevalence of epilepsy.Conclusion: Patients who died of COVID-19 under the age of 50 were 10 to 20 times more likely to have epilepsy than what would have been expected from epidemiological data. Our results highlight the need for increased protection of young people with epilepsy from COVID-19 infection and the development of a vaccination strategy accordingly. [ABSTRACT FROM AUTHOR]

The changes in extensive thermodynamic quantities, such as volume, energy, Helmholtz free energy and entropy, occurring upon mixing liquid methanol with supercritical CO2, are calculated using Monte Carlo simulations and thermodynamic integration for all eight combinations of four methanol and two CO2 potential models in the entire composition range at 313 K. The obtained results are also compared with experimental data whenever possible. The transition of the system from liquid to a supercritical state is found to occur at this temperature around a CO2 mole fraction value of 0.95 with all model combinations considered. This liquid to supercritical transition is always accompanied by positive Helmholtz free energy of mixing values and, consequently, by the non-miscibility of the two components. Furthermore, both this non-miscibility around the liquid to supercritical transition and also the miscibility of the two components below this transition, in the liquid regime, are found to be primarily of the energetic rather than entropic origin; the entropy of mixing turns out to be very close to zero, and around the liquid to supercritical transition even its qualitative behaviour is strongly model dependent. Finally, it is found that the methanol expansion coefficient is not sensitive to the details of the potential models, and it is always in excellent agreement with the experimental data. On the other hand, both the volume and the energy of mixing depend strongly on the molar volume of neat CO2 in the model being used, and in this respect the TraPPE model of CO2 [J. J. Potoff and J. I. Siepmann, AIChE J., 2001, 47, 1676] performs considerably better than that of Zhang and Duan [Z. Zhang and Z. Duan, J. Chem. Phys., 2005, 122, 214507]. [ABSTRACT FROM AUTHOR]