The crossed-hands deficit in temporal order judgments occurs for present, future, and past hand postures

When people judge the temporal order (TOJ task) of two tactile stimuli at the two hands while their hands are crossed, performance is much worse than with uncrossed hands [1]. This crossed-hands deficit is widely considered to indicate interferences of external spatial coordinates with body-centered coordinates in the localization of touch [2]. Similar deficits have also been observed when people are only about to move their hands towards a crossed position [3]-[5], suggesting a predictive update of external spatial coordinates. Here, we extend the investigation of the dynamics of external coordinates during hand movement. Participants performed a TOJ task while they executed an uncrossing or a crossing movement, and during presentation of the TOJ stimuli the present posture of the hands was crossed, uncrossed or in-between. Present, future and past crossed-hands postures decreased performance in the TOJ task, suggesting that the update of external spatial coordinates of touch includes both predictive processes and processes that preserve the recent past. In addition, our data corroborate the flip model of crossed-hands deficits [1], and suggest that more pronounced deficits come along with higher time requirements to resolve interferences

Spatial modelling of sulphur deficiency in crops in Germany

Schwefelmangel führt bei landwirtschaftlichen Kulturen zu Ertrags- und Qualitätsminderung. Verringerte Schwefeldepositionen in Agrarflächen und gestiegene Produktivität der Kulturpflanzen sowie die hohe Dynamik des pflanzenverfügbaren Schwefels im Boden sind Hauptgründe für das Auftreten von Schwefelmangel. Prognosemodelle helfen, das Risiko von Schwefelmangel abzuschätzen, zu bewerten und das landwirtschaftliche Management darauf anzupassen. Ziel dieser Arbeit war es, das pot. Schwefelmangelrisiko für Deutschland zu modellieren. Dabei lag der Fokus auf der Ausarbeitung der räumlichen Heterogenitäten des Risikos innerhalb Deutschlands, ohne Berücksichtigt der anthropogenen Einträge. Es entstand die Möglichkeit das Schwefelmangelrisiko für Gebiete Deutschlands zu vergleichen und besonders sensible Bereiche hervorzuheben. Dazu wurden aus der Literatur bekannte Faktoren, die Schwefelmangel an Kulturpflanzen begünstigen, berücksichtigt und bewertet. Neben dem aktuellen Klima wurde auch auf ein Szenario einer möglichen Klimaänderung in der Zukunft eingegangen. Die Untersuchungen führten zu folgenden Ergebnissen: Durch die Klassifizierung der Austauschhäufigkeit des Bodenwassers unter Berücksichtigung der Grundwasserbeeinflussung kann davon ausgegangen werden, dass etwa 25% der landwirtschaftlichen Fläche eine sehr geringe pot. Sulfatauswaschung, 20% eine geringe, 33% eine moderate, 10% eine hohe und 12% eine sehr hohe Sulfatauswaschung aufweisen. Bei einem Szenario der prognostizierte Klimaänderung verstärkt sich das Risiko der Sulfatauswaschung. Die Berücksichtigung der atmosphärischen Deposition am Schwefelentzug ermöglicht eine relative Einschätzung zwischen dem pot.n Auswaschungsrisiko und den atmosphärischen Einträgen auf Kreisebene. Dabei zeigen sich deutliche Heterogenitäten des Schwefelmangelrisikos innerhalb Deutschlands. Es konnte aufgezeigt werden, dass die jährliche atmosphärische Deposition von Schwefel den Entzug durch die Pflanzen nicht decken kann. Durch das zukünftig erhöhte Sulfatauswaschungsrisiko wird das Schwefelmangelrisiko zunehmen und Schwefel als essentieller Pflanzennährstoff mehr Aufmerksamkeit benötigen.Sulphur deficiency decreases the yield of crops and influences the final yield quality. Spatial models enable to estimate the risk of sulphur deficiency on a national scale and help to adjust crop management. The objective of this study was to identify the risk of sulphur deficiency for different crops and show its spatial distributions. The spatial model was based on the major factors which favour the risk of sulphur deficiency. Hence the groundwater influence and the soil water balance were regarded as the major factors for the risk assessment of the potential sulphate leaching. The proportion of annual atmospheric sulphur deposition to the side and crop specific sulphur removals could also be calculated on a spatial scale and enabled the final assessment of the risk of sulphur deficiency. In addition to the current climate conditions it was possible to model the influence of a predicted climate change scenario. The research resulted in following results: The classification of the exchange frequency of the soil water under consideration of the groundwater shows that about 25% of agricultural areas are very low, 20% are low, 33% are moderately, 10% are high, and 12% are very high endangered for sulphate leaching. The predicted climate change will affect the soil water balance and the potential washout of sulphur and enhance the sulphate leaching. There are significant differences in the risk of sulphur deficiency within Germany. By taking the atmospheric sulphur deposition and the heterogeneous sulphur removals of different crops into account, a relative assessment of the sulphur deficiency risk could be enabled on a spatial scale. The deposition rates cannot meet the crop removals. Particularly with regard to the changing climate, the risk of sulphur deficiency will increase and sulphur as essential plant nutrient will need more attention to secure an optimal crop growth and development

Auswirkung eines Knockouts des Protein-Phosphatase-Inhibitor-1 auf den Verlauf der druckinduzierten Herzinsuffizienz in Mäusen

Aims Protein Phosphatase Inhibitor 1 (I-1) functions as an amplifier of the β-adrenergic cascade in cardiomyocytes. Once activated via PKA, I-1 specifically blocks PP-1-mediated dephosphorylation of phospholamban and the ryanodine receptor-1. In heart failure I-1 activity as well as its expression is significantly reduced. It is still unclear whether this adaptation is protective or detrimental. This work aims at examining the impact of I-1 depletion on the course of pressure-induced heart failure, more precisely on acute and long-term mortality, on cardiac morphology and function and on expression levels of hypertrophy markers. Results may help evaluating the benefit of putative I-1 inhibiting substances in the therapy of heart failure. Methods and Results 25 I-1KO and 28 WT mice (C57Bl/6J, age- and sex-matched) underwent transverse aortic constriction (TAC). Cardiac function was assessed via transthoracic echocardiography prior to the intervention and weekly afterwards. Additionally, mice were exposed to β-adrenergic stimulation by injection of dobutamine once prior to TAC and two times afterwards, each controlled by echocardiography. For male mice acute survival was significantly increased in WT compared to I-1KO, whereas the mortality of surviving animals did not differ during the investigation period. For female mice no difference was seen in acute mortality after TAC, but during heart failure progression I-1KO revealed a significantly better survival. Prior to TAC contractility in I-1KO after application of dobutamine was significantly lower than in WT. This effect was mainly induced by female mice. Overall female mice of both WT and I-1KO showed smaller increases in heart rate (HR) and stroke volume (SV) when stimulated. In contrast, following TAC neither line- nor sex-dependent differences were found according to β-adrenergic stimulation. The comparison of hypertrophy markers in control groups revealed clearly decreased levels for I-1KO compared to WT. Conclusion In pressure-induced heart failure, I-1 knockout alters cardiac contractility and modulates mortality in a phase- and sex-dependent way. The depletion is detrimental for male mice in the acute phase of cardiac stress, whereas it is protective for female mice during heart failure progression. The increased mortality in the acute phase might result from the loss of I-1 as an amplifier of β-adrenergic signaling as this leads to a restriction of contractile adaptation. The increased survival in heart failure progression might be caused by a reduced transmission of pathologically increased sympathetic activity on the SR due to the depletion of I-1. Additionally, hypertrophy marker analyses point to differences in expression levels even under non-pathological conditions.Ziel Der Proteinphosphatase-Inhibitor I-1 wirkt als ein Verstärker der β-adrenergen Kaskade in Kardiomyozyten. Nach PKA-abhängiger Phosphorylierung hemmt er spezifisch die Dephosphorylierung von PLB und RYR-2 durch die Proteinphosphatase-1. Im Rahmen einer Herzinsuffizienz sind sowohl Aktivität als auch Expression von I-1 deutlich reduziert. Hierbei ist unklar, ob dies eine protektive oder eine schädliche Adaption der β-adrenergen Kaskade darstellt. Diese Arbeit untersucht den Einfluss einer Depletion des I-1 (I-1KO) im Rahmen der druckinduzierten Herzinsuffizienz auf die akute bzw. auf die langfristige Mortalität, auf die kardiale Morphologie und Funktion sowie auf die Expression typischer Hypertrophiemarker. Hieraus sollen Erkenntnisse über den Nutzen der Verwendung putativ I-1 inhibierender Substanzen in der Behandlung der Herzinsuffizienz gewonnen werden. Methoden und Resultate 25 I-1KO- sowie 28 WT-Mäuse (C57Bl/6J, age and sex matched) erhielten eine Transverse Aortic Constriction (TAC). Die kardiale Funktion wurde einmalig vor der Intervention sowie danach wöchentlich mittels TTE untersucht. Zusätzlich wurden die Tiere einmalig vor TAC und zweimalig danach unter echokardiographischer Kontrolle mittels Dobutamin β-adrenerg stimuliert. Für die männlichen Tiere zeigte sich in den ersten Tagen nach TAC eine signifikant erhöhte Überlebensrate des WT gegenüber I-1KO. Die Mortalität der überlebenden männlichen Tiere unterschied sich hingegen nicht über den Versuchszeitraum. Für die weiblichen Tiere bestand kein Unterschied in der akuten Sterblichkeit nach TAC, während sich im Verlauf eine signifikant bessere Überlebensrate der weiblichen I-1KO gegenüber WT zeigte. Vor TAC wurde eine signifikant herabgesetzte Kontraktilität (FAS) des I-1KO unter Dobutamin festgestellt, der im Wesentlichen durch die weiblichen Tiere bewirkt wird. Insgesamt zeigten die weiblichen Tiere beider Linien unter β-adrenerger Stimulation eine geringere Zunahme von Herzfrequenz (HR) und Schlagvolumen (SV). Hingegen waren nach TAC keine linien- oder geschlechtsabhängigen Unterschiede unter Dobutamingabe feststellbar. Ein Vergleich der Hypertrophiemarker in der Kontrollgruppe zeigte für I-1KO ein deutlich vermindertes Niveau der Marker gegenüber WT. Ergebnis Der I-1-Knockout verändert die kardiale Kontraktilität und wirkt sowohl in phasen- als auch in geschlechtsabhängiger Weise auf die Mortalität infolge druckinduzierter Herzinsuffizienz. Er ist nachteilig für männliche Tiere in der akuten Phase kardialer Belastung, während er für weibliche Tiere im weiteren Verlauf protektive Wirkung entfaltet. Eine erhöhte Mortalität in der akuten Phase kann durch den Ausfall der Verstärkerfunktion des I-1 erklärt werden, da hiermit eine Einschränkung der akut notwendigen kontraktilen Adaptionsfähigkeit einhergeht. Ein Überlebensvorteil bei chronischer kardialer Belastung könnte darauf zurückzuführen sein, dass die pathologisch erhöhte sympathische Aktivierung der β-adrenergen Kaskade infolge der I-1-Depletion eine geringere Auswirkung auf die Zielstrukturen des aktivierten I-1 am Sarkoplasmatischen Retikulum hat. Darüber hinaus lassen die Analysen der Hypertrophiemarker eine veränderte Genexpression zwischen I-1KO und WT auch unter nicht-pathologischen Bedingungen vermuten

Correlation of passivity symptoms and dysfunctional visuomotor action monitoring in psychosis

Passivity experiences are hallmark symptoms of schizophrenia that can be characterized by the belief that one's thoughts or actions are controlled by an external agent. It has recently been suggested that these psychotic experiences result from defective monitoring of one's own actions, i.e. disturbed comparison of actions and perceived outcomes. In this study, we examined the function of the previously characterized action monitoring network of the inferior parietal lobule (IPL), medial (mPFC) and lateral prefrontal cortices in patients with different levels of passivity symptoms with an fMRI task. The visuomotor fMRI task demanded control of visually perceived object movements by alternating button presses with the left and the right index finger. In the monitoring condition of this task subjects stopped their actions whenever they detected visuomotor incongruence. fMRI and behavioural data from 15 patients were tested for correlation with passivity symptoms using standardized Scale for Assessment of Positive Symptoms (SAPS)- and AMDP- passivity symptom ratings. Both types of data were tested for differences between the patients group and 15 healthy controls. In the patient group we found the expected correlation of passivity symptoms and visuomotor monitoring performance. There was a significant positive correlation of passivity symptoms with increased latency of incongruence detection and a negative correlation of SAPS-passivity with the number of detected events. fMRI data revealed correlations of passivity symptoms with activation in bilateral IPL, primary motor and sensory cortices in the action monitoring condition. A correlation of passivity symptoms with the main experimental effect (actions with - actions without monitoring) was found in the posterior cingulate cortex (PCC) and in the left IPL. No group differences or group by task interactions were found within the visuomotor-action-monitoring network. Our results demonstrate the association between passivity symptoms and the dysfunction of visuomotor action monitoring and support the idea that psychotic passivity experiences result from dysfunctions of central action monitoring mechanisms: According to pre-existing concepts of parietal cortex function, IPL-hyperactivation may represent an increase in false detections of visuomotor incongruence while the correlation between passivity and the differential effect of monitoring on PCC-activation assumedly represents greater self-monitoring effort in passivity experience

Single-objective high-resolution confocal light sheet fluorescence microscopy for standard biological sample geometries

Three-dimensional fluorescence-based imaging of living cells and organisms requires the sample to be exposed to substantial excitation illumination energy, typically causing phototoxicity and photobleaching. Light sheet fluorescence microscopy dramatically reduces phototoxicity, yet most implementations are limited to objective lenses with low numerical aperture and particular sample geometries that are built for specific biological systems. To overcome these limitations, we developed a single-objective light sheet fluorescence system for biological imaging based on axial plane optical microscopy and digital confocal slit detection, using either Bessel or Gaussian beam shapes. Compared to spinning disk confocal microscopy, this system displays similar optical resolution, but a significantly reduced photobleaching at the same signal level. This single-objective light sheet technique is built as an add-on module for standard research microscopes and the technique is compatible with high-numerical aperture oil immersion objectives and standard samples mounted on coverslips. We demonstrate the performance of this technique by imaging three-dimensional dynamic processes, including bacterial biofilm dispersal, the response of biofilms to osmotic shocks, and macrophage phagocytosis of bacterial cells

Correlation of passivity symptoms and dysfunctional visuomotor action monitoring in psychosis

Passivity experiences are hallmark symptoms of schizophrenia that can be characterized by the belief that one's thoughts or actions are controlled by an external agent. It has recently been suggested that these psychotic experiences result from defective monitoring of one's own actions, i.e. disturbed comparison of actions and perceived outcomes. In this study, we examined the function of the previously characterized action monitoring network of the inferior parietal lobule (IPL), medial (mPFC) and lateral prefrontal cortices in patients with different levels of passivity symptoms with an fMRI task. The visuomotor fMRI task demanded control of visually perceived object movements by alternating button presses with the left and the right index finger. In the monitoring condition of this task subjects stopped their actions whenever they detected visuomotor incongruence. fMRI and behavioural data from 15 patients were tested for correlation with passivity symptoms using standardized Scale for Assessment of Positive Symptoms (SAPS)- and AMDP- passivity symptom ratings. Both types of data were tested for differences between the patients group and 15 healthy controls. In the patient group we found the expected correlation of passivity symptoms and visuomotor monitoring performance. There was a significant positive correlation of passivity symptoms with increased latency of incongruence detection and a negative correlation of SAPS-passivity with the number of detected events. fMRI data revealed correlations of passivity symptoms with activation in bilateral IPL, primary motor and sensory cortices in the action monitoring condition. A correlation of passivity symptoms with the main experimental effect (actions with – actions without monitoring) was found in the posterior cingulate cortex (PCC) and in the left IPL. No group differences or group by task interactions were found within the visuomotor-action-monitoring network. Our results demonstrate the association between passivity symptoms and the dysfunction of visuomotor action monitoring and support the idea that psychotic passivity experiences result from dysfunctions of central action monitoring mechanisms: According to pre-existing concepts of parietal cortex function, IPL-hyperactivation may represent an increase in false detections of visuomotor incongruence while the correlation between passivity and the differential effect of monitoring on PCC-activation assumedly represents greater self-monitoring effort in passivity experiences