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Risk factors for and meaning of basal ganglia calcifications outside Fahr syndrome are poorly understood. We aimed to assess the prevalence of basal ganglia calcifications and the association with vascular risk factors.

The Laser Interferometer Space Antenna (LISA) has two scientific objectives of cosmological focus: to probe the expansion rate of the universe, and to understand stochastic gravitational-wave backgrounds and their implications for early universe and particle physics, from the MeV to the Planck scale. However, the range of potential cosmological applications of gravitational-wave observations extends well beyond these two objectives. This publication presents a summary of the state of the art in LISA cosmology, theory and methods, and identifies new opportunities to use gravitational-wave observations by LISA to probe the universe.

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Introduction:Lesion volume on MRI or CT provides evidence of tissue response to successful recanalization by endovascular therapy. The most appropriate time to estimate “infarct” volume remains unclear. Largely for convenience, 24-48 hours has been used in clinical trials and registry datasets which may be too early to determine the final infarct volume. The objective of this study was to quantify the comparability of lesion volume using MRI measured at 24 hours versus 5 days in acute stroke patients following successful recanalization.Methods:Patients were included if they consented to the prospective GUARDS study between April 2018 through February 2022, had LVO of the anterior circulation, were treated with EVT, achieved complete revascularization defined as TICI 2b/3, and imaged with MRI at 2 hours, 24 hours, and 5 days post EVT. Two independent readers measured lesion volumes using a semi-automated validated approach on DWI at 2 and 24 hours, and FLAIR at 5 days. Statistical comparisons of lesion volumes across time points were performed. Lesion growth was defined as change in lesion volume and percent change compared to lesion volume at 2 hours.Results:Sixty-nine patients met all study criteria and were included. Median age was 66 years, 55% female, median admit NIHSS of 18, 62% with M1 LVO, and 46% treated with IV thrombolysis. Post-EVT median lesion volumes were 24mL, 35mL, and 45mL respectively for 2-hour DWI, 24-hour DWI, and 5-day FLAIR. Lesion growth based on median percent change from the 2-hour DWI was 39% [21-96] and 52% [12-145] at 24 hours and 5 days. The difference in lesion growth based on percent change from 24 hours to 5 days was not significant (p=0.17). However, there was a significant difference based on change in lesion volume, 12mL [2-25] at 24 hours and 16mL at 5 days (p=0.029). Fifty-one (74%) patients had DWI volumes at 24 hours that were ≥80% of their FLAIR volumes at 5 days. However, 18 (26%) patients continued to have lesion growth beyond 24 hours, median lesion growth of 18mL,with 11 (61%) of those having lesion growth >20mL.Conclusions:Lesion growth >20mL continues in some patients beyond 24 hours, suggesting that infarct volume at 5 days should be used as the imaging outcome when assessing tissue response to recanalization.

Introduction:A substantial proportion of acute stroke patients experience poor outcomes following successful endovascular therapy (EVT) and reperfusion injury to the brain and vasculature may be a contributor. The purpose of this pilot study was to characterize hyperemia following recanalization and test the association of hyperemia with evolution of the ischemic lesion.Methods:Acute stroke patients were included with: i) large vessel occlusion of the anterior circulation, ii) successful recanalization, and iii) evaluable MRI early after EVT. Presence of hyperemia on MRI perfusion was assessed by consensus using a modified ASPECTS. Three different approaches were used to quantify relative cerebral blood flow (rCBF) on early post-EVT, 24 hours, and 5 days. Two independent trained readers measured lesion volumes using a semi-automated validated approach.Results:Sixty-seven patients with median age of 66 [59-76], 57% female, met inclusion criteria. Hyperemia was present in 35/67 (52%) patients early post-EVT (Figure), in 32/65 (49%) patients at 24 hours, and in 19/48 (40%) patients at 5 days. In comparison to control regions, rCBF was elevated by greater than 50% in hyperemic regions. Patients with hyperemia had larger ischemic lesion volumes and early lesion growth. A strong association (R2=0.81, p<0.001) was found between early post-EVT hyperemia (p=0.027) and lesion growth based on DWI volume at 24 hours, after adjusting for DWI volume at 2 hours (p<0.001) and incomplete reperfusion at 24 hours (p=0.001).Conclusions:Hyperemia is frequently observed after successful EVT and is associated with lesion growth at 24 hours. Evidence of hyperemia may identify patients that may benefit from adjunctive therapy to prevent reperfusion injury, edema, and lesion growth.

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Perinatal disturbances of brain hemodynamics can have a detrimental effect on the brain’s parenchyma with consequently adverse neurodevelopmental outcome. Noninvasive, reliable tools to evaluate the neonate’s brain hemodynamics are scarce. Advances in magnetic resonance imaging have provided new methods to noninvasively assess brain hemodynamics. More recently these methods have made their transition to the neonatal population. The aim of this review is twofold. Firstly, to describe these newly available noninvasive methods to investigate brain hemodynamics in neonates. Secondly, to discuss the results that were obtained with these techniques, identifying both potential clinical applications as well as gaps of knowledge.

Background:Arterial spin labeling (ASL) magnetic resonance imaging (MRI) can evaluate brain perfusion in neonates noninvasively. The aim of this study was to investigate whether ASL MRI can demonstrate perfusion abnormalities in neonates diagnosed with perinatal arterial ischemic stroke (PAIS).Methods:Pulsed ASL perfusion MR images were acquired in the subacute stage (5–6 d after birth) and at follow-up (13 d to 16?wk after birth) in four PAIS patients. Images were visually evaluated for hypo- and hyperperfusion. In addition, cerebral oxygenation was monitored using near infrared spectroscopy (NIRS).Results:In three PAIS patients, ASL images showed hypoperfusion in the stroke area. In one of these, hyperperfusion was visualized in the periphery of the stroke area. In one PAIS patient, hyperperfusion was seen in the stroke area. In all infants, cerebral oxygenation was higher in the infarcted hemisphere as compared with the contralateral hemisphere. Follow-up ASL images showed partial recovery of perfusion in the stroke area.Conclusion:ASL perfusion MRI is able to reliably detect hypo- and hyperperfusion in PAIS patients and can be used to monitor the evolution of perfusion after an ischemic event.

Targets withstanding high beam power for production of 68Ge by proton irradiation of Ga were developed using electrodeposition of Ga/Ni alloy (70/30%) on thick Cu backings. Cross sections for reactions, induced by protons (up to 36MeV) and deuterons (up to 50MeV), producing γ-emitting radioisotopes with half-lives longer than 2 h were measured in a stacked-foil irradiation using thin Ga/Ni targets produced with this technique. Excitation functions for 68,69Ge are discussed, relative to the monitor reactions natCu(p, x)62Zn or natAl(d, x)24,22Na. The results are compared to the scarce literature values. From derived thick target yields, optimal energy domain and batch yields for 68Ge production were calculated and contamination (from 69Ge and 71Ge) is discussed. A PC-controlled, automated dissolution and separation chemistry set-up for delivery of nca 69Ge was developed (yield about 90%) and implemented in an industrial system ready to be mounted in a hot cell.

One of the neuropsychological deficits that can result from a stroke is the neglect phenomenon. Neglect has traditionally been assessed with paper-and-pencil tasks, which are administered within the reaching space of a person. The purpose of this explorative study is to investigate whether it is possible to assess neglect in the extrapersonal space based on the performance of acute stroke patients, chronic stroke patients and healthy elderly in orientation and exploration tasks when immersed in a three-dimensional (3D)-virtual environment. Six able-bodied healthy elderly and 12 stroke patients (six subacute and six chronic) participated in this explorative cross-sectional study. Neglect was assessed by means of the 3D neglect test. Different parameters were measured at two challenge levels with increasing difficulty. In the easiest level significant differences between the groups were found for total time spent in the test, mean response time left field of vision, and mean response time in the left field of vision of the left virtual reality environment. Differences in search patterns showed that subacute stroke patients had a much more fuzzy search pattern in scanning the environment than healthy elderly and chronic stroke patients. With respect to the more difficult level results showed significant differences between healthy elderly and the total group of stroke patients. The results of this study suggest that a 3D neglect test by means of virtual reality has the potential to detect and measure unilateral neglect.

The foraging behavior of Amitus fuscipennisMacGown & Nebeker and Encarsia formosaGahan was studied on tomato leaflets with 20 Trialeurodes vaporariorum(Westwood) larvae in the first or third stage. Ten of the whitefly larvae were previously parasitized and contained a conspecific or a heterospecific parasitoid egg or larva. The host type (host stage and/or previous parasitization) did not influence the foraging behavior of either parasitoid species. The residence time on these tomato leaflets was about 0.9 h for A. fuscipennisand 1.9 h for E. formosa. Amitus fuscipennishardly stood still and fed little, while E. formosashowed extensive standing still and feeding. As a result, the time walking while drumming was similar for both parasitoid species. The numbers of host encounters and ovipositions per leaflet were similar for both parasitoid species. However, the residence time of A. fuscipenniswas half as long as that of E. formosaso the rate of encounters and ovipositions was higher for A. fuscipennis. Amitus fuscipennisis more efficient in finding and parasitizing hosts under these conditions. The walking activity and host acceptance of the synovigenic E. formosadiminished with the number of ovipositions, but not those of the proovigenic A. fuscipennis. Encarsia formosais egg limited, while A. fuscipennisis time limited because of its short life span and high egg load. Both parasitoid species discriminated well between unparasitized larvae and self-parasitized larvae, but discriminated poorly those larvae parasitized by a conspecific and did not discriminate larvae parasitized by a heterospecific. Self-superparasitism, conspecific superparasitism, and multiparasitism were observed for both parasitoid species. Superparasitism always resulted in the emergence of one parasitoid and multiparasitism resulted in a higher emergence of one parasitoid of the species that had parasitized first. The data suggest that A. fuscipennisis a good candidate for use in biological control of high-density spots of T. vaporariorumwhen we consider its high encounter and oviposition rate.

Positron emission tomography is a potential method for exploring the biochemical behaviour of tumours. In 28 patients with known neoplastic lesions a comparison was made between two agents which are known to be accumulated in malignant tumours, viz. 13N-ammonia and 11C-aminocyclopentane carboxylic acid (ACPC). Absolute concentration of both agents in various tumoural tissues and normal organs was calculated. As a rule a parallelism was found between the two tracers as to their accumulation in a given tumour, although the concentration was often higher for ACPC. In normal tissues the ACPC accumulation was either lower or at most equal to NH, levels. As tumour tracer ACPC is superior to NH3 because of its higher absolute accumulation in many neoplastic lesions and its lower uptake in various non-tumorous tissues. ACPC concentration in tumours seems to be largely independent of blood flow.