julilili42/papers huggingface dataset:
Stimulation Artifact Source Separation (SASS) for assessing electric brain oscillations during transcranial alternating current stimulation (tACS)
2020-04-04

Abstract Brain oscillations, e.g. measured by electro- or magnetoencephalography (EEG/MEG), are causally linked to brain functions that are fundamental for perception, cognition and learning. Recent advances in neurotechnology provide means to non-invasively target these oscillations using frequency-tuned amplitude-modulated transcranial alternating current stimulation (AM-tACS). However, online adaptation of stimulation parameters to ongoing brain oscillations remains an unsolved problem due to stimulation artifacts that impede such adaptation, particularly at the target frequency. Here, we introduce a real-time compatible artifact rejection algorithm (Stimulation Artifact Source Separation, SASS) that overcomes this limitation. SASS is a spatial filter (linear projection) removing EEG signal components that are maximally different in the presence versus absence of stimulation. This enables the reliable removal of stimulation-specific signal components, while leaving physiological signal components unaffected. For validation of SASS, we evoked brain activity with known phase and amplitude using 10 Hz visual flickers across 7 healthy human volunteers. 64-channel EEG was recorded during and in absence of 10 Hz AM-tACS targeting the visual cortex. Phase differences between AM-tACS and the visual stimuli were randomized, so that steady-state visually evoked potentials (SSVEPs) were phase-locked to the visual stimuli but not to the AM-tACS signal. For validation, distributions of single-trial amplitude and phase of EEG signals recorded during and in absence of AM-tACS were compared for each participant. When no artifact rejection method was applied, AM-tACS stimulation artifacts impeded assessment of single-trial SSVEP amplitude and phase. Using SASS, amplitude and phase of single trials recorded during and in absence of AM-tACS were comparable. These results indicate that SASS can be used to establish adaptive (closed-loop) AM-tACS, a potentially powerful tool to target various brain functions, and to investigate how AM-tACS interacts with electric brain oscillations. Highlights - Stimulation Artifact Source Separation (SASS), a real-time compatible signal decomposition algorithm for separating electric brain activity and stimulation signal artifacts related to amplitude-modulated transcranial alternating current stimulation (AM-tACS), is introduced - Employing SASS, phase and amplitude of single-trial steady state visual evoked potentials (SSVEPs) were reliably recovered from electroencephalography (EEG) recordings at the frequency targeted with AM-tACS - SASS enables assessment of single-trial oscillatory brain activity at the target frequency during stimulation and paves the way for online adaptation of stimulation parameters to ongoing brain oscillations
Binocular disparity-based learning is retinotopically specific and independent of sleep
2020-04-05

Sleep supports the consolidation of recently encoded declarative and procedural memories. An important component of this effect is the repeated reactivation of neuronal ensemble activity elicited during memory encoding. For perceptual learning, however, sleep benefits have only been reported for specific tasks and it is not clear whether sleep targets low-level perceptual, higher-order temporal or attentional aspects of performance. Here, we employed a coarse binocular disparity discrimination task, known to rely on low-level stereoscopic vision. We show that human subjects improve over training and retain the same performance level across a 12-h retention period. Improvements do not generalize to other parts of the visual field and are unaffected by whether the retention period contains sleep or not. These results are compatible with the notion that behavioural improvements in binocular disparity discrimination do not additionally benefit from sleep when compared with the same time spent awake. We hypothesize that this might generalize to other strictly low-level perceptual tasks. This article is part of the Theo Murphy meeting issue ‘Memory reactivation: replaying events past, present and future'.
Brain responsivity provides an individual readout for motor recovery after stroke
2020-04-06

Abstract Promoting the recovery of motor function and optimizing rehabilitation strategies for stroke patients is closely associated with the challenge of individual prediction. To date, stroke research has identified critical pathophysiological neural underpinnings at the cellular level as well as with regard to network reorganization. However, in order to generate reliable readouts at the level of individual patients and thereby realize translation from bench to bedside, we are still in a need for innovative methods. The combined use of transcranial magnetic stimulation (TMS) and EEG has proven powerful to record both local and network responses at an individual’s level. To elucidate the potential of TMS-EEG to assess motor recovery after stroke, we used neuronavigated TMS-EEG over ipsilesional primary motor cortex (M1) in 28 stroke patients in the first days after stroke. Twenty-five of these patients were reassessed after &amp;gt;3 months post-stroke. In the early post-stroke phase (6.7 ± 2.5 days), the TMS-evoked EEG responses featured two markedly different response morphologies upon TMS to ipsilesional M1. In the first group of patients, TMS elicited a differentiated and sustained EEG response with a series of deflections sequentially involving both hemispheres. This response type resembled the patterns of bilateral activation as observed in the healthy comparison group. By contrast, in a subgroup of severely affected patients, TMS evoked a slow and simplified local response. Quantifying the TMS-EEG responses in the time and time-frequency domain revealed that stroke patients exhibited slower and simple responses with higher amplitudes compared to healthy controls. Importantly, these patterns of activity changes after stroke were not only linked to the initial motor deficit, but also to motor recovery after &amp;gt;3 months post-stroke. Thus, the data revealed a substantial impairment of local effects as well as causal interactions within the motor network early after stroke. Additionally, for severely affected patients with absent motor evoked potentials and identical clinical phenotype, TMS-EEG provided differential response patterns indicative of the individual potential for recovery of function. Thereby, TMS-EEG extends the methodological repertoire in stroke research by allowing the assessment of individual response profiles.
Relation of X-ray activity and rotation in M dwarfs and predicted time-evolution of the X-ray luminosity
2020-04-06

The relation of activity to rotation in M dwarfs is of high astrophysical interest because it provides observational evidence of the stellar dynamo, which is poorly understood for low-mass stars, especially in the fully convective regime. Previous studies have shown that the relation of X-ray activity to rotation consists of two different regimes: the saturated regime for fast-rotating stars and the unsaturated regime for slowly rotating stars. The transition between the two regimes lies at a rotation period of ∼10 d. We present here a sample of 14 M dwarf stars observed with XMM-Newton and Chandra , for which we also computed rotational periods from Kepler Two-Wheel (K2) Mission light curves. We compiled X-ray and rotation data from the literature and homogenized all data sets to provide the largest uniform sample of M dwarfs (302 stars) for X-ray activity and rotation studies to date. We then fit the relation between L x − P rot using three different mass bins to separate partially and fully convective stars. We found a steeper slope in the unsaturated regime for fully convective stars and a nonconstant L x level in the saturated regime for all masses. In the L x / L bol − R O space we discovered a remarkable double gap that might be related to a discontinuous period evolution. Then we combined the evolution of P rot predicted by angular momentum evolution models with our new results on the empirical L x − P rot relation to provide an estimate for the age decay of X-ray luminosity. We compare predictions of this relationship with the actual X-ray luminosities of M stars with known ages from 100 Myr to a few billion years. We find remarkably good agreement between the predicted L x and the observed values for partially convective stars. However, for fully convective stars at ages of a few billion years, the constructed L x -age relation overpredicts the X-ray luminosity because the angular momentum evolution model underpredicts the rotation period of these stars. Finally, we examine the effect of different parameterizations for the Rossby number ( R O ) on the shape of the activity-rotation relation in L x / L bol − R O space, and we find that the slope in the unsaturated regime and the location of the break point of the dual power-law depend sensitively on the choice of R O .
Supersolid Properties of a Bose-Einstein Condensate in a Ring Resonator
2020-04-06

We investigate the dynamics of a Bose-Einstein condensate interacting with two noninterfering and counterpropagating modes of a ring resonator. Superfluid, supersolid, and dynamic phases are identified experimentally and theoretically. The supersolid phase is obtained for sufficiently equal pump strengths for the two modes. In this regime we observe the emergence of a steady state with crystalline order, which spontaneously breaks the continuous translational symmetry of the system. The supersolidity of this state is demonstrated by the conservation of global phase coherence at the superfluid to supersolid phase transition. Above a critical pump asymmetry the system evolves into a dynamic runaway instability commonly known as collective atomic recoil lasing. We present a phase diagram and characterize the individual phases by comparing theoretical predictions with experimental observations.
The phenotype of adverse drug effects: Do emergency visits due to adverse drug reactions look different in older people? Results from the ADRED study
2020-04-06

Aims Older patients in particular suffer from adverse drug reactions (ADR) when presenting in the emergency department. We aimed to characterise the phenotype of those ADRs, to be able to recognise an ADR in older patients. Methods Cases of ADRs in emergency departments collected within the multicentre prospective observational study (ADRED) were analysed ( n = 2215). We analysed ADR‐associated diagnoses, symptoms and their risk profiles. We present frequencies and odds ratios (OR) with 95% confidence intervals for adults (18–64 years) compared to older adults (≥65 years; young–old 65–79, old–old ≥80 years) and regression coefficients (B) for each year of age. Results Most prominent differences were seen for drug‐associated confusion, dehydration, and bradycardia (OR 6.70 [1.59–28.27], B .054; OR 6.02 [2.41–15.03], B .081, and 4.82 [2.21–10.54], B .040), more likely seen in older adults. Bleedings were reported in all age groups, but gastrointestinal bleedings occurred with more than doubled chance in older adults (OR 2.46 [1.77–3.41], B .030), likewise did other bleedings such as haemorrhage from respiratory passages (OR 2.89 [1.37–6.11], B.036). Falls were more likely in older adults (OR 2.84 [1.77–4.53], B .030), while dizziness was frequent in both age groups. Conclusion Our data point to differences in symptoms of ADRs between adults and older individuals, with dangerous drug‐associated phenomena in the older adult such as bleedings or falls. Physicians should consider drug‐associated origins of symptoms in older adults with an increased risk for serious health problems.
ERP and oscillatory differences in overweight/obese and normal-weight adolescents in response to food stimuli
2020-04-06

Abstract Background Findings are mixed regarding the association of electroencephalographic (EEG) attentional bias measures and body weight, with few studies measuring food craving or intake and no study reporting oscillatory measures. Methods EEG data were collected while 28 satiated adolescents (14 overweight/obese) viewed pictures of neutral, low-calorie food, and high-calorie food stimuli and rated their desire to eat, before having access to high-calorie snacks. Results Unlike normal-weight adolescents, overweight/obese participants showed similar P300 amplitudes for high- and low-calorie food, and strongest event-related alpha band desynchronization for low-calorie stimuli. P300 amplitudes and state craving for low-calorie food furthermore predicted snack intake in this group. Conclusions The current research focus in overweight/obesity might need to be extended to include low-calorie food. While all participants showed an attentional bias for high-calorie food, it was the processing of low-calorie food which distinguished the two weight groups on measures of neural activity and which was associated with snack food intake in the overweight/obese group.
Ammonia and coma – a case report of late onset hemizygous ornithine carbamyltransferase deficiency in 68-year-old female
2020-04-06

Abstract Background Acute hyperammonemia without signs of common causes in the elderly might be challenging to identify. We report the oldest case known to date of a female patient with late onset ornithine carbamyltransferase deficiency (OTC), which was unmasked after a protein overload due to nutritional supplements. Our case illustrates how environmental factors (protein overload) in previously unknown OTC in the elderly leads to hyperammonemic encephalopathy and highlights that early treatment prevents persisting neurological deficits and should be considered in absence of common causes of hyperammonemic encephalopathy. Case presentation A 68-year-old woman presented with acute confusion, which progressed into a deep coma (Glasgow-Coma-Scale score 3) within a few hours. The only remarkable finding was a plasma ammonia (NH3) concentration of 697 μmmol/l (range 12–47 μmmol/). Third party history revealed that the patient disliked meat for most of her life (meat = protein, which needs to be metabolized) and had taken nutritional supplements (since supplements often have a high protein-ratio) 2 days before the symptoms started. Protein catabolism results in NH3, which is metabolized via the urea cycle. Consequently, the acute hyperammonemia in our patient was thought to be related to an inherited metabolic disorder, which only unmasked itself as a result of an overload of the corresponding metabolite (in this case protein). Since ornithine carbamyltransferase deficiency (OTC) is the most common inherited urea cycle disorder, this diagnosis became likely and was confirmed later via genetic and metabolic testing (amino acids, orotic acid, etc.). After 2 weeks of treatment (dialysis, low-protein-diet, nitrogen-lowering medication) the patient was discharged in a healthy condition without any neurological deficits. Conclusion OTC is a x-chromosomal linked disorder, that usually manifests in newborn infants and children, but also rarely in adults and even rarer in the elderly (50- till 60-years-old), where it is probably underdiagnosed. In case of hyperammonemic encephalopathy – regardless of the underlying cause -, treatment should be started early to prevent persisting neurological deficits. OTC should be considered in absence of common causes of hyperammonemic encephalopathy.
Aerosol-spread during chest compressions in a cadaver model
2020-04-06

Abstract Objective To evaluate aerosol-spread in cardiopulmonary resuscitation (CPR) using different methods of airway management. Knowledge about aerosol-spread is vital during the SARS-CoV-2-Pandemic. Methods To evaluate feasibility we nebulized ultraviolet sensitive detergents into the artificial airway of a resuscitation dummy and performed CPR. The spread of the visualized aerosol was documented by a camera. In a second approach we applied nebulized detergents into human cadavers by an endotracheal tube and detected aerosol-spread during chest compressions the same way. We did recordings with undergoing compression-only-CPR, with a surgical mask and with an inserted laryngeal tube with and without a connected airway filter. Results Most aerosol-spread at the direction of the provider was visualized during compression-only-CPR. The use of a surgical mask deflected the spread. Inserting a laryngeal tube connected to an airway filter lead to a remarkable reduction of aerosol-spread. Conclusion The early insertion of a laryngeal tube connected to an airway filter before starting chest compression may be good for two things – the treatment of hypoxemia as the likeliest cause of cardiac arrest and for staff protection during CPR.
Revealing the local crystallinity of single silicon core-shell nanowires using tip-enhanced Raman spectroscopy
2020-04-06

Tip-enhanced Raman spectroscopy is combined with polarization angle-resolved spectroscopy to investigate the nanometre-scale structural properties of core-shell silicon nanowires (crystalline Si core and amorphous Si shell), which were synthesized by platinum-catalyzed vapor-liquid-solid growth and silicon overcoating by thermal chemical vapour deposition. Local changes in the fraction of crystallinity are characterized for those silicon nanowires at an optical resolution of about 300 nm. Furthermore, we are able to resolve the variations in the intensity ratios between the crystalline Si and the amorphous Si Raman peaks by applying tip-enhanced Raman spectroscopy, at sample positions being eight nanometers apart. The local crystallinity revealed using confocal Raman spectroscopy and tip-enhanced Raman spectroscopy agree well with the high-resolution transmission electron microscopy measurements. Additionally, the polarizations of Raman scattering and the photoluminescence signal from the tip-sample nanogap are explored by combining polarization angle-resolved emission spectroscopy with tip-enhanced optical spectroscopy. Our work demonstrates the significant potential of resolving local structural properties of Si nanomaterials at the sub-10 nanometer scale using tip-enhanced Raman techniques.
A common polymorphism in the mechanosensitive ion channel PIEZO1 is associated with protection from severe malaria in humans
2020-04-07

Significance The clinical presentation of Plasmodium falciparum malaria as severe versus uncomplicated is influenced by host genetic factors. Recently, a gain-of-function mutation in the mechanosensitive ion channel PIEZO1 was shown to protect mice against cerebral malaria, but its role in human malaria is unknown. Here we investigated a common PIEZO1 variant that encodes a mild gain-of-function mutant in human erythrocytes, and show that it is associated with malaria protection in Gabonese children. We found an epistatic relationship between PIEZO1 E756del and the sickle cell trait. While parasite growth and cell hydration were normal, surface expression of PfEMP-1 was reduced in the mutant cells. Understanding the link between common PIEZO1 variants and malaria susceptibility may yield new therapies for malaria.
Efficacy of Topical Ivermectin for the Treatment of Cutaneous and Ocular Rosacea
2020-04-07

<b>Purpose</b>: To investigate the efficacy of once-daily topical treatment of ocular and cutaneous rosacea with ivermectin 1% cream (Soolantra®, Galderma).<b>Methods</b>: Ten patients with rosacea were evaluated in a retrospective monocentric pilot study. Subjective symptoms (measured with the Ocular Surface Disease Index), skin findings, and ocular changes (blepharitis with telangiectasia and meibomian gland dysfunction, conjunctival redness, tear breakup time (TBUT), and fluorescein staining of the cornea) were evaluated. The follow-up was 8 months (range: 5-12 months).<b>Results</b>: The OSDI score decreased in the 8th week of treatment (38.5 ± 21.7, <i>P</i> = .004). After 16 weeks, blepharitis (<i>P</i> = .004), and conjunctival redness (<i>P</i> = .008) had strongly improved, and grade 1 was seen in all patients until the end of follow-up. Fluorescein staining of the cornea (<i>P</i> = .001) and TBUT (<i>P</i> = .016) showed significant improvement until the last follow-up visit. No side effects were observed. <b>Conclusion</b>: Topical ivermectin cream 1% given daily is an effective and safe therapy against rosacea.
“In situ similis” Culturing of Plant Microbiota: A Novel Simulated Environmental Method Based on Plant Leaf Blades as Nutritional Pads
2020-04-07

High-throughput cultivation methods have recently been developed to accelerate the recovery of microorganisms reluctant to cultivation. They simulate <i>in situ</i> environmental conditions for the isolation of environmental microbiota through the exchange of growth substrates during cultivation. Here, we introduce leaf-based culture media adopting the concept of the plant being the master architect of the composition of its microbial community. Pre-physical treatments of sunflower plant leaves, namely punching, freezing, and/or autoclavation, allowed the diffusion of electrolytes and other nutrients to configure the leaf surface as a natural pad, i.e., creating an "<i>in situ similis</i>" environment suitable for the growth of rarely isolated microbiota. We used surface inoculation and membrane-filtration methods to assess the culturability of endophytic bacteria from the sunflower phyllosphere and rhizosphere. Both methods supported excellent colony-forming unit (CFU) development when compared to standard R2A medium, with a special affinity to support better growth of epiphytic and endophytic populations of the phyllosphere compared with the rhizosphere. A 16S rRNA gene analysis of >122 representative isolates indicated the cultivation of a diverse set of microorganisms by application of the new methods. It indicated the predominance of 13 genera of >30 potential species, belonging to Firmicutes, Proteobacteria, and Actinobacteria, and especially genera not commonly reported for sunflower, e.g., <i>Rhizobium</i>, <i>Aureimonas</i>, <i>Sphingomonas</i>, <i>Paracoccus</i>, <i>Stenotrophomonas</i>, <i>Pantoea</i>, <i>Kosakonia</i>, and <i>Erwinia</i>. The strategy successfully extended diversity and richness in the endophyllosphere compared to the endorhizosphere, while CFUs grown on the standard R2A medium mainly pertain to Firmicutes, especially <i>Bacillus</i> spp. MALDI-TOF MS analysis clustered the isolates according to their niche and potential functions, where the majority of isolates of the endorhizosphere were clustered away from those of the endophyllosphere. Isolates identified as Gammaproteobacteria and Alphaproteobacteria were distinguishably sub-clustered, which was in contrast to the heterogeneous isolates of Firmicutes (<i>Bacillus</i> spp.). In conclusion, leaf <i>in situ similis</i> cultivation is an effective strategy to support the future application of culturomics of plant microbiota. This is an effort to access novel isolates that are more adapted and competitive in their natural environments, especially those subjected to abiotic stresses like those prevailing in arid/semi-arid zones, and, consequently, to support the application of agro-biotechnologies, among other technologies, to improving agriculture in such zones.