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Sniffing behavior of semi free‐ranging Barbary macaques (Macaca sylvanus)
No full textOlfaction is one of the evolutionarily oldest senses and plays a fundamental role in foraging and social interactions across mammals. In primates, the role of olfaction is now well recognized, but better investigated in strepsirrhine and platyrrhine primates than in catarrhines. We observed the sniffing behavior of semi-free ranging Barbary macaques, Macaca sylvanus, at Affenberg Salem, Germany, to assess how frequently macaques sniff and in which contexts, and how sniffing is affected by sex and age. Focal observations of 24 males and 24 females aged 1–25 years showed that Barbary macaques sniffed, on average, 5.24 times per hour, with more than 80% of sniffs directed at food. Irrespective of the context, younger individuals sniffed more often than older ones. Females’ sniffs were more often directed at food than male sniffs, while males sniffed more often than females in a social context. Sniffs at conspecifics occurred primarily in a sexual context, with 70% of social sniffs directed at female anogenital swellings performed by males. Of the observed 176 anogenital inspections, 51 involved sniffing of the swelling. Olfactory inspections were followed by copulation significantly less often than merely visual inspections, suggesting that anogenital odors may play a role in male mating decisions, but the role of olfaction in sexual interactions warrants further investigations. In sum, results show that Barbary macaques routinely use olfaction during feeding, but also in a socio-sexual context, corroborating the relevance of the olfactory sense in the lives of catarrhine primates
Prognostic role of radiomics-based body composition analysis for the 1-year survival for hepatocellular carcinoma patients
No full textParameters of body composition have prognostic potential in patients with oncologic diseases. The aim of the present study was to analyse the prognostic potential of radiomics-based parameters of the skeletal musculature and adipose tissues in patients with advanced hepatocellular carcinoma (HCC)
Predictive Algorithm for Surgery Recommendation in Thoracolumbar Burst Fractures Without Neurological Deficits
No full textArtificial intelligence (AI) remain an emerging field and have not previously been used to guide therapeutic decision making in thoracolumbar burst fractures. Building such models may reduce the variability in treatment recommendations. The goal of this study was to build a mathematical prediction rule based upon radiographic variables to guide treatment decisions
Prognostic Relevance of Globocardial Work Index in Patients with Moderate Aortic Valve Stenosis
No full textBackground: A reduced global myocardial work index (GWI) ≤ 1951 mmHg% is associated
with increased mortality in patients with severe aortic valve stenosis (AS). However, parameters
predicting the outcome in patients with moderate AS are limited. Therefore, the aim of this study was
to evaluate the prognostic value of the GWI in patients with moderate AS. Methods and Results: In
this prospective study, 103 patients with moderate AS (mean age 72 ± 10 years; male: 69%) underwent
standardized transthoracic echocardiography. The primary endpoint was survival without an aortic
valve replacement (AVR). After a median follow-up of 30 ± 5 months, 37 patients (36%) were referred
for an AVR. Survival without an AVR was 96% at 12 months and 80% at 30 months ( >1951 mmHg%)
versus 96% and 68% (≤1951 mmHg%). A GWI ≤ 1951 mmHg% did not predict the need for
an AVR (hazard ratio 1.31 (95% CI, 0.63–2.72), p = 0.49). Furthermore, there was no significant
correlation between the mean GWI (1644 ± 448 mmHg%) and mean aortic valve pressure gradient
(24.2 mmHg ± 6.2, p = 0.615) or effective aortic orifice area (1.24 cm2 ± 0.11, p = 0.678). There was no
difference between the AVR and non-AVR groups in the occurrence of clinical symptoms. Conclusion:
In contrast to patients with severe AS, a GWI ≤ 1951 mmHg% did not predict the need for an AVR.
Further research is needed to improve the risk stratification in patients with moderate AS
Simulation-Assisted Augmentation of Missing Wedge and Region-of-Interest Computed Tomography Data
No full textThis study reports a strategy to use sophisticated, realistic X-ray Computed Tomography
(CT) simulations to reduce Missing Wedge (MW) and Region-of-Interest (RoI) artifacts in FBP (Filtered
Back-Projection) reconstructions. A 3D model of the object is used to simulate the projections that
include the missing information inside the MW and outside the RoI. Such information augments
the experimental projections, thereby drastically improving the reconstruction results. An X-ray CT
dataset of a selected object is modified to mimic various degrees of RoI and MW problems. The
results are evaluated in comparison to a standard FBP reconstruction of the complete dataset. In all
cases, the reconstruction quality is significantly improved. Small inclusions present in the scanned
object are better localized and quantified. The proposed method has the potential to improve the
results of any CT reconstruction algorithm
That sounds awful! Does sound unpleasantness modulate the mismatch negativity and its habituation?
No full textThere are sounds that most people perceive as highly unpleasant, for instance, the sound of rubbing pieces of polystyrene together. Previous research showed larger physiological and neural responses for such aversive compared to neutral sounds. Hitherto, it remains unclear whether habituation, i.e., diminished responses to repeated stimulus presentation, which is typically reported for neutral sounds, occurs to the same extent for aversive stimuli. We measured the mismatch negativity (MMN) in response to rare occurrences of aversive or neutral deviant sounds within an auditory oddball sequence in 24 healthy participants, while they performed a demanding visual distractor task. Deviants occurred as single events (i.e., between two standards) or as double deviants (i.e., repeating the identical deviant sound in two consecutive trials). All deviants elicited a clear MMN, and amplitudes were larger for aversive than for neutral deviants (irrespective of their position within a deviant pair). This supports the claim of preattentive emotion evaluation during early auditory processing. In contrast to our expectations, MMN amplitudes did not show habituation, but increased in response to deviant repetition—similarly for aversive and neutral deviants. A more fine-grained analysis of individual MMN amplitudes in relation to individual arousal and valence ratings of each sound item revealed that stimulus-specific MMN amplitudes were best predicted by the interaction of deviant position and perceived arousal, but not by valence. Deviants with perceived higher arousal elicited larger MMN amplitudes only at the first deviant position, indicating that the MMN reflects preattentive processing of the emotional content of sounds
Temporal variability of observed and simulated gross primary productivity, modulated by vegetation state and hydrometeorological drivers
No full textThe gross primary production (GPP) of the terrestrial biosphere is a key source of variability in the global carbon cycle. It is modulated by hydrometeorological drivers (i.e. short-wave radiation, air temperature, vapour pressure deficit and soil moisture) and the vegetation state (i.e. canopy greenness, leaf area index) at instantaneous to interannual timescales. In this study, we set out to evaluate the ability of GPP models to capture this variability. Eleven models were considered, which rely purely on remote sensing data (RS-driven), meteorological data (meteo-driven, e.g. dynamic global vegetation models; DGVMs) or a combination of both (hybrid, e.g. light-use efficiency, LUE, models). They were evaluated using in situ observations at 61 eddy covariance sites, covering a broad range of herbaceous and forest biomes.
The results illustrated how the determinant of temporal variability shifts from meteorological variables at sub-seasonal timescales to biophysical variables at seasonal and interannual timescales. RS-driven models lacked the sensitivity to the dominant drivers at short timescales (i.e. short-wave radiation and vapour pressure deficit) and failed to capture the decoupling of photosynthesis and canopy greenness (e.g. in evergreen forests). Conversely, meteo-driven models accurately captured the variability across timescales, despite the challenges in the prognostic simulation of the vegetation state. The largest errors were found in water-limited sites, where the accuracy of the soil moisture dynamics determines the quality of the GPP estimates. In arid herbaceous sites, canopy greenness and photosynthesis were more tightly coupled, resulting in improved results with RS-driven models. Hybrid models capitalized on the combination of RS observations and meteorological information. LUE models were among the most accurate models to monitor GPP across all biomes, despite their simple architecture.
Overall, we conclude that the combination of meteorological drivers and remote sensing observations is required to yield an accurate reproduction of the spatio-temporal variability of GPP. To further advance the performance of DGVMs, improvements in the soil moisture dynamics and vegetation evolution are needed
Drowning and Nonfatal Drowning in Children and Adolescents: A Subsequent Retrospective Data Analysis
No full textFatal and nonfatal drowning are among the leading causes of death and lifelong severe neurological impairment among children and adolescents. This study aimed to complement research from Leipzig 1994–2008 to seek trends within risk factors, treatments, and outcomes throughout the last decade. We retrospectively investigated data of 47 inpatients aged 0–18 admitted to Leipzig University Department of Pediatrics who matched ICD-10 code T75.1 from 2008 to 2020 and compared them to a preceding study at the same institution. We also examined the prognostic value of parameters regarding the patients’ outcomes. There were three median incidents per annum. The median age was 2.75 years; 76% of incidents happened in males. An accumulation was seen during the summer months and weekends. Most drowning incidents occurred in private ponds or pools (48.9%). Thirty-nine children were discharged without resulting morbidity, four showed neurological impairment, and three died. Risk factors concerning age, sex, and incident characteristics were confirmed. Special supervision needs still apply to 1–3-year-old male children or children with pre-existing health conditions around private pools and ponds. Hospitalization duration shortened, and morbidity and lethality decreased since the previous study. There was structural improvement in primary care and medical documentation. Parameters suggesting good outcomes include a submersion time 3 points, spontaneous movement upon admission, remaining pupillary light response, the absence of cardiovascular arrest, body temperature ≥ 32 °C, pH > 7, blood glucose < 15 mmol/L, lactate < 14 mmol/L, base excess ≥ −15 mmol/L, and the absence of ARDS. Clear legislation can contribute to improved private home water safety. Further studies should include a broad in- and outpatient spectrum and standardized incident documentation presupposing Utstein-style reporting. Regular reinvestigation of consistent geographical regions facilitates process evaluations of drowning epidemiology and therapy evolution
Red Shift in the Absorption Spectrum of Phototropin LOV1 upon the Formation of a Semiquinone Radical: Reconstructing the Orbital Architecture
No full textFlavin mononucleotide (FMN) is a ubiquitous blue-light pigment due to its ability to drive one- and two-electron transfer reactions. In both light-oxygen-voltage (LOV) domains of phototropin from the green algae Chlamydomonas reinhardtii, FMN is noncovalently bound. In the LOV1 cysteine-to-serine mutant (C57S), light-induced electron transfer from a nearby tryptophan occurs, and a transient spin-correlated radical pair (SCRP) is formed. Within this photocycle, nuclear hyperpolarization is created by the solid-state photochemically induced dynamic nuclear polarization (photo-CIDNP) effect. In a side reaction, a stable protonated semiquinone radical (FMNH·) forms undergoing a significant bathochromic shift of the first electronic transition from 445 to 591 nm. The incorporation of phototropin LOV1-C57S into an amorphous trehalose matrix, stabilizing the radical, allows for application of various magnetic resonance experiments at ambient temperatures, which are combined with quantum-chemical calculations. As a result, the bathochromic shift of the first absorption band is explained by lifting the degeneracy of the molecular orbital energy levels for electrons with alpha and beta spins in FMNH· due to the additional electron
Ni-Alloyed Copper Iodide Thin Films: Microstructural Features and Functional Performance
No full textTo tailor electrical properties of often degenerate pristine CuI, Ni is introduced as
alloy constituent. Cosputtering in a reactive, but also in an inert atmosphere as
well as pulsed laser deposition (PLD), is used to grow Nix Cu 1x I thin films. The
Ni content within the alloy thin films is systematically varied for different growth
techniques and growth conditions. A solubility limit is evidenced by an additional
NiI 2ðH2 OÞ6 phase for Ni contents x ≥ 0.31, observed in X-Ray diffraction and
atomic force microscopy by a change in surface morphology. Furthermore,
metallic, nanoscaled nickel clusters, revealed by X-Ray photoelectron spectros-
copy and high-resolution transmission electron microscopy (HRTEM), underpin
a solubility limit of Ni in CuI. Although no reduction of charge carrier density is
observed with increasing Ni content, a dilute magnetic behavior of the thin films
is observed in vibrating sample magnetometry. Further, independent of the
deposition technique, unique multilayer features are observed in HRTEM
measurements for thin films of a cation composition of x ≈ 0.06. Opposite to
previous claims, no transition to n-type behavior was observed, which was also
confirmed by density functional theory calculations of the alloy system