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From 5.5 months of dual-band optical photometric monitoring at the 1 mmag level, BRITE-Constellation has revealed two simultaneous types of variability in the O4I(n)fp star ζ Puppis: one single periodic non-sinusoidal component superimposed on a stochastic component. The monoperiodic component is the 1.78-d signal previously detected by Coriolis/Solar Mass Ejection Imager, but this time along with a prominent first harmonic. The shape of this signal changes over time, a behaviour that is incompatible with stellar oscillations but consistent with rotational modulation arising from evolving bright surface inhomogeneities. By means of a constrained non-linear light-curve inversion algorithm, we mapped the locations of the bright surface spots and traced their evolution. Our simultaneous ground-based multisite spectroscopic monitoring of the star unveiled cyclical modulation of its He ii λ4686 wind emission line with the 1.78-d rotation period, showing signatures of corotating interaction regions that turn out to be driven by the bright photospheric spots observed by BRITE. Traces of wind clumps are also observed in the He ii λ4686 line and are correlated with the amplitudes of the stochastic component of the light variations probed by BRITE at the photosphere, suggesting that the BRITE observations additionally unveiled the photospheric drivers of wind clumps in ζ Pup and that the clumping phenomenon starts at the very base of the wind. The origins of both the bright surface inhomogeneities and the stochastic light variations remain unknown, but a subsurface convective zone might play an important role in the generation of these two types of photospheric variability.
Mimicking non-verbal emotional expressions and empathy development in simulated consultations
(2018)
Objective: To explore the feasibility of applying an experimental design to study the relationship between non-verbal emotions and empathy development in simulated consultations.
Method: In video-recorded simulated consultations, twenty clinicians were randomly allocated to either an experimental group (instructed to mimic non-verbal emotions of a simulated patient, SP) or a control group (no such instruction). Baseline empathy scores were obtained before consultation, relational empathy was rated by SP after consultation. Multilevel logistic regression modelled the probability of mimicry occurrence, controlling for baseline empathy and clinical experience. ANCOVA compared group differences on relational empathy and consultation smoothness.
Results: Instructed mimicry lasted longer than spontaneous mimicry. Mimicry was marginally related to improved relational empathy. SP felt being treated more like a whole person during consultations with spontaneous mimicry. Clinicians who displayed spontaneous mimicry felt consultations went more smoothly.
Conclusion: The experimental approach improved our understanding of how non-verbal emotional mimicry contributed to relational empathy development during consultations. Further work should ascertain the potential of instructed mimicry to enhance empathy development.
Practice implications: Understanding how non-verbal emotional mimicry impacts on patients’ perceived clinician empathy during consultations may inform training and intervention programme development.
Phytochemical investigation of the CH2Cl2/MeOH (1:1) extract of the roots of Lannea rivae (Chiov) Sacleux (Anacardiaceae) led to the isolation of a new alkenyl cyclohexenone derivative: (4R,6S)-4,6-dihydroxy-6-((Z)-nonadec-14′-en-1-yl)cyclohex-2-en-1-one (1), and a new alkenyl cyclohexanol derivative: (2S*,4R*,5S*)-2,4,5-trihydroxy-2-((Z)-nonadec-14′-en-1-yl)cyclohexanone (2) along with four known compounds, namely epicatechin gallate, taraxerol, taraxerone and β-sitosterol; while the stem bark afforded two known compounds, daucosterol and lupeol. Similar investigation of the roots of Lannea schweinfurthii (Engl.) Engl. led to the isolation of four known compounds: 3-((E)-nonadec-16′-enyl)phenol, 1-((E)-heptadec-14′-enyl)cyclohex-4-ene-1,3-diol, catechin, and 1-((E)-pentadec-12′-enyl)cyclohex-4-ene-1,3-diol. The structures of the isolated compounds were determined by NMR spectroscopy and mass spectrometry. The absolute configuration of compound 1 was established by quantum chemical ECD calculations. In an antibacterial activity assay using the microbroth kinetic method, compound 1 showed moderate activity against Escherichia coli while compound 2 exhibited moderate activity against Staphylococcus aureus. Compound 1 also showed moderate activity against E. coli using the disc diffusion method. The roots extract of L. rivae was notably cytotoxic against both the DU-145 prostate cancer cell line and the Vero mammalian cell line (CC50 = 5.24 and 5.20 μg/mL, respectively). Compound 1 was also strongly cytotoxic against the DU-145 cell line (CC50 = 0.55 μg/mL) but showed no observable cytotoxicity (CC50 > 100 μg/mL) against the Vero cell line. The roots extract of L. rivae and L. schweinfurthii, epicatechin gallate as well as compound 1 exhibited inhibition of carageenan-induced inflammation.
This article examines the reorganization of formal coordination structures in the Directorate-General for Fisheries and Maritime Affairs of the European Commission. While rational approaches in organization theory emphasize functional efficiency as an explanation for organizational design and coordination structures, the findings of this study indicate that the reorganization was not driven primarily for reasons of efficiency and to increase the coordination capacity of the organization. The study demonstrates that, even in a highly technical policy area such as fisheries management in the European Union, the (re-)design of formal organizational structures does not follow primarily a technical-instrumental rationale. Instead, the formal coordination structures have also been adapted to live up to changing expectations in the institutional environment, to modern management concepts in marine governance, and to ensure the legitimacy of the organization. However, although the empirical findings of this study substantiate the theoretical assumptions of an institutional perspective, institutional explanations alone are insufficient to comprehensively understand why organizational structures are reorganized and changed.
The first molecularly imprinted polymer (MIP) for the recognition of the copper-enzyme laccase was successfully prepared by electropolymerizing scopoletin in the presence of alkaline-inactivated enzyme. Laccase-MIP and the control polymer without laccase (nonimprinted polymer, NIP) were characterized by voltammetry using the redox marker ferricyanide. After electropolymerization, the signals for ferricyanide for both the MIP and the NIP were almost completely suppressed and increased after removal of the target from the polymer layer. Rebinding of both inactivated and active laccase decreased the ferricyanide peak currents to almost equal extent. The relative decrease of signal suppression approached saturation above 10 nM. Furthermore, the surface activity of rebound laccase toward the oxidation of catechol was investigated. The surface activity approached saturation above 10 nM, a value close to the value of the measurements with ferricyanide. Interaction of NIP with laccase brought about a six times smaller signal of catechol oxidation.
We provide an abstract definition and an explicit construction of the stack of non-Abelian Yang-Mills fields on globally hyperbolic Lorentzian manifolds. We also formulate a stacky version of the Yang-Mills Cauchy problem and show that its well-posedness is equivalent to a whole family of parametrized PDE problems. Our work is based on the homotopy theoretical approach to stacks proposed in Hollander (Isr. J. Math. 163:93-124, 2008), which we shall extend by further constructions that are relevant for our purposes. In particular, we will clarify the concretification of mapping stacks to classifying stacks such as BG (con).
High-velocity clouds (HVCs) are interstellar clouds of atomic hydrogen that do not follow normal Galactic rotation and have velocities of a several hundred kilometres per second. A considerable number of these clouds are falling down towards the Galactic disc. HVCs form large and massive complexes, so if they collide with the disc a great amount of energy would be released into the interstellar medium. The cloud-disc interaction produces two shocks: one propagates through the cloud and the other through the disc. The properties of these shocks depend mainly on the cloud velocity and the disc-cloud density ratio. In this work, we study the conditions necessary for these shocks to accelerate particles by diffusive shock acceleration and we study the non-thermal radiation that is produced. We analyse particle acceleration in both the cloud and disc shocks. Solving a time-dependent two-dimensional transport equation for both relativistic electrons and protons, we obtain particle distributions and non-thermal spectral energy distributions. In a shocked cloud, significant synchrotron radio emission is produced along with soft gamma rays. In the case of acceleration in the shocked disc, the non-thermal radiation is stronger; the gamma rays, of leptonic origin, might be detectable with current instruments. A large number of protons are injected into the Galactic interstellar medium, and locally exceed the cosmic ray background. We conclude that under adequate conditions the contribution from HVC-disc collisions to the galactic population of relativistic particles and the associated extended non-thermal radiation might be important.
The Timpa delle Murge ophiolite in the North Calabrian Unit is part of the Liguride Complex (southern Apennines). The study is concentrated on the gabbroic part of the ophiolite of the Pollino area. They preserve the high-grade ocean floor metamorphic and locally developed flaser textures under ocean floor conditions. The primary magmatic assemblages are clinopyroxene, plagioclase, and opaques. Brown hornblende is a late magmatic phase. Green hornblende, actinolite, albite, chlorite and epidote display metamorphic recrystallization under lower amphibolite facies conditions, followed by greenschist facies. The gabbros show subalkaline near to alkaline character with a tendency to a more calkalkaline trend. The normalization to primitive mantle and mid-ocean ridge basalt (N-MORB) compositions indicates a considerable depletion in Nb, P, Zr and Ti and an enrichment in Ba, Rb, K, Sr and Eu. This points to a mantle source, which is not compatible with a "normal" mid-ocean ridge situation. Rather, the gabbros are generated from a N-MORB-like melt with a strong crustal component, which was influenced by subduction related fluids and episodic melting during mid-ocean-ridge processes. Plausible geodynamic settings of the Timpa delle Murge gabbros are oceanic back-arc positions with embryonic MORB-activities. Similar slab contaminated magmatism is also known from the early stage of island arc formation in supra-subduction zone environments like the Izu-Bonin-Mariana island arc.
Functional dependencies (FDs) play an important role in maintaining data quality. They can be used to enforce data consistency and to guide repairs over a database. In this work, we investigate the problem of missing values and its impact on FD discovery. When using existing FD discovery algorithms, some genuine FDs could not be detected precisely due to missing values or some non-genuine FDs can be discovered even though they are caused by missing values with a certain NULL semantics. We define a notion of genuineness and propose algorithms to compute the genuineness score of a discovered FD. This can be used to identify the genuine FDs among the set of all valid dependencies that hold on the data. We evaluate the quality of our method over various real-world and semi-synthetic datasets with extensive experiments. The results show that our method performs well for relatively large FD sets and is able to accurately capture genuine FDs.
According to the Shallow Structure Hypothesis (SSH), second language (L2) speakers, unlike native speakers, build shallow syntactic representations during sentence processing. In order to test the SSH, this study investigated the processing of a syntactic movement in both native speakers of English and proficient late L2 speakers of English using pupillometry to measure processing cost. Of particular interest were constructions where movement resulted in an intermediate gap between clauses. Pupil diameter was recorded during auditory presentation of complex syntactic constructions. Two factors were manipulated: syntactic movement (such that some conditions contained movement while others did not), as well as syntactic movement type (either causing an intermediate gap or not). Grammaticality judgments revealed no differences between the two groups, suggesting both were capable of comprehending these constructions. Pupil change slope measurements revealed a potential sensitivity to intermediate gaps for only native speakers, however, both native and late L2 speakers showed similar facilitation during processing of the second gap site. Acoustic analysis revealed potential acoustic cues that may have facilitated the processing of these constructions. This suggests that, contrary to the predictions of the SSH, late L2 speakers are capable of constructing rich syntactic representations during the processing of intermediate gap constructions in spoken language.
Surface electromyographic (EMG) signal amplitude is typically used to compare the neural drive to muscles. We experimentally investigated this association by studying the motor unit (MU) behavior and action potentials in the vastus medialis (VM) and vastus lateralis (VL) muscles. Eighteen participants performed isometric knee extensions at four target torques [10. 30. 50, and 70% of the maximum torque (MVC)] while high-density EMG signals were recorded from the VM and VL. The absolute EMG amplitude was greater for VM than VL (P < 0.001), whereas the EMG amplitude normalized with respect to MVC was greater for VL than VM (P < 0.04). Because differences in EMG amplitude can be due to both differences in the neural drive and in the size of the MU action potentials, we indirectly inferred the neural drives received by the two muscles by estimating the synaptic inputs received by the corresponding motor neuron pools. For this purpose. we analyzed the increase in discharge rate from recruitment to target torque for motor units matched by recruitment threshold in the two muscles. This analysis indicated that the two muscles received similar levels of neural drive. Nonetheless, the size of the MU action potentials was greater for VM than VL (P < 0.001), and this difference explained most of the differences in EMG amplitude between the two muscles (similar to 63% of explained variance). These results indicate that EMG amplitude, even following normalization, does not reflect the neural drive to synergistic muscles. Moreover, absolute EMG amplitude is mainly explained by the size of MU action potentials. NEW & NOTEWORTHY Electromyographic (EMG) amplitude is widely used to compare indirectly the strength of neural drive received by synergistic muscles. However, there are no studies validating this approach with motor unit data. Here, we compared between-muscles differences in surface EMG amplitude and motor unit behavior. The results clarify the limitations of surface EMG to interpret differences in neural drive between muscles.
In this study, we developed an autodetection technique for the equatorial plasma depletions (EPDs) and their occurrence and depletion amplitudes based on in situ electron density measurements gathered by Swarm A satellite. For the first time, comparisons are made among the detected EPDs and their amplitudes with the loss of Global Positioning System (GPS) signal of receivers onboard Swarm A, and the Swarm Level-2 product, Ionospheric Bubble Index (IBI). It has been found that the highest rate of EPD occurrence takes place generally between 2200 and 0000 magnetic local time (MLT), in agreement with the IBI. However, the largest amplitudes of EPD are detected earlier at about 1900-2100 MLT. This coincides with the moment of higher background electron density and the largest occurrence of GPS signal loss. From a longitudinal perspective, the higher depletion amplitude is always witnessed in spatial bins with higher background electron density. At most longitudes, the occurrence rate of postmidnight EPDs is reduced compared to premidnight ones; while more postmidnight EPDs are observed at African longitudes. CHAMP observations confirm this point regardless of high or low solar activity condition. Further by comparing with previous studies and the plasma vertical drift velocity from ROCSAT-1, we suggest that while the F region vertical plasma drift plays a key role in dominating the occurrence of EPDs during premidnight hours, the postmidnight EPDs are the combined results from the continuing of former EPDs and newborn EPDs, especially during June solstice. And these newborn EPDs during postmidnight hours seem to be less related to the plasma vertical drift.
The present study aimed at identifying latent profiles of body image concerns in adolescents and young adults. Subsequently, associations between these profiles and potentially harmful behaviors are examined. Self-report data of 758 male and female adolescents, aged 14 to 22 years, were analyzed. Participants provided demographic and anthropometric data and completed surveys on weight/shape and muscularity concern as well as on disturbed eating behaviors and dysfunctional exercise. Latent profile analyses of weight/shape concern and muscularity concern were performed separately for each gender. The analyses indicated three-class solutions in men and women. In both genders, the inconspicuous class, characterized by small amounts of weight/shape and muscularity concerns, was the largest one (86% in men, 68% in women). Whereas 10% of the men and 23% of the women were assigned to the borderline class, 4% of the men and 8% of the women formed the conspicuous class (marked weight/shape and muscularity concerns). Between genders, the degrees of muscularity concern differed in the borderline and inconspicuous classes, while the degrees of weight/shape concern differed in the inconspicuous class only. The comparable degrees of weight/shape and muscularity concerns in men and women in the affected classes underline the relevance of both aspects in both genders. Classes could be distinguished by harmful behaviors, like restrained eating or emotional exercise, proving the clinical significance of body image concerns.
Morphological inhomogeneities and structural defects in organic semiconductors crucially determine the charge accumulation and lateral transport in organic thin-film transistors. Photoluminescence Electro-Modulation (PLEM) microscopy is a laser-scanning microscopy technique that relies on the modulation of the thin-film fluorescence in the presence of charge-carriers to image the spatial distribution of charges within the active organic semiconductor. Here, we present a lock-in scheme based on a scanning beam approach for increasing the PLEM microscopy resolution and contrast. The charge density in the device is modulated by a sinusoidal electrical signal, phase-locked to the scanning beam of the excitation laser. The lock-in detection scheme is achieved by acquiring a series of images with different phases between the beam scan and the electrical modulation. Application of high resolution PLEM to an organic transistor in accumulation mode demonstrates its potential to image local variations in the charge accumulation. A diffraction-limited precision of sub-300 nm and a signal to noise ratio of 21.4 dB could be achieved. Published by AIP Publishing.
With its exhortation “You shall also love the stranger (gēr), for you were strangers (gērîm) in the land of Egypt” (Deut 10:19), the book of Deuteronomy helps cultivate a healthy and appreciative sense of past hardship, current prosperity, progress, and relative privilege. In contemporary culture, where the term “privilege” has become an unfortunate source of contention, Deuteronomy might point a way for recognition of one’s relative privilege in regard to an Other as a basis for gratitude and responsibility. This essay argues that we have gained “privilege” after having been immigrants and strangers in a strange land. Privilege could become an empowering and challenging exercise of counting one’s blessings and considering how these could be used for the benefit of others, including strangers in our land.
We prove finiteness and diameter bounds for graphs having a positive Ricci-curvature bound in the Bakry–Émery sense. Our first result using only curvature and maximal vertex degree is sharp in the case of hypercubes. The second result depends on an additional dimension bound, but is independent of the vertex degree. In particular, the second result is the first Bonnet–Myers type theorem for unbounded graph Laplacians. Moreover, our results improve diameter bounds from Fathi and Shu (Bernoulli 24(1):672–698, 2018) and Horn et al. (J für die reine und angewandte Mathematik (Crelle’s J), 2017, https://doi.org/10.1515/crelle-2017-0038) and solve a conjecture from Cushing et al. (Bakry–Émery curvature functions of graphs, 2016).
Admixture is the hybridization between populations within one species. It can increase plant fitness and population viability by alleviating inbreeding depression and increasing genetic diversity. However, populations are often adapted to their local environments and admixture with distant populations could break down local adaptation by diluting the locally adapted genomes. Thus, admixed genotypes might be selected against and be outcompeted by locally adapted genotypes in the local environments. To investigate the costs and benefits of admixture, we compared the performance of admixed and within-population F1 and F2 generations of the European plant Lythrum salicaria in a reciprocal transplant experiment at three European field sites over a 2-year period. Despite strong differences between site and plant populations for most of the measured traits, including herbivory, we found limited evidence for local adaptation. The effects of admixture depended on experimental site and plant population, and were positive for some traits. Plant growth and fruit production of some populations increased in admixed offspring and this was strongest with larger parental distances. These effects were only detected in two of our three sites. Our results show that, in the absence of local adaptation, admixture may boost plant performance, and that this is particularly apparent in stressful environments. We suggest that admixture between foreign and local genotypes can potentially be considered in nature conservation to restore populations and/or increase population viability, especially in small inbred or maladapted populations.
Noninvasive near-infrared (NIR) light responsive therapy is a promising cancer treatment modality; however, some inherent drawbacks of conventional phototherapy heavily restrict its application in clinic. Rather than producing heat or reactive oxygen species in conventional NIR treatment, here a multifunctional yolk-shell nanoplatform is proposed that is able to generate microbubbles to destruct cancer cells upon NIR laser irradiation. Besides, the therapeutic effect is highly improved through the coalition of small interfering RNA (siRNA), which is codelivered by the nanoplatform. In vitro experiments demonstrate that siRNA significantly inhibits expression of protective proteins and reduces the tolerance of cancer cells to bubble-induced environmental damage. In this way, higher cytotoxicity is achieved by utilizing the yolk-shell nanoparticles than treated with the same nanoparticles missing siRNA under NIR laser irradiation. After surface modification with polyethylene glycol and transferrin, the yolk-shell nanoparticles can target tumors selectively, as demonstrated from the photoacoustic and ultrasonic imaging in vivo. The yolk-shell nanoplatform shows outstanding tumor regression with minimal side effects under NIR laser irradiation. Therefore, the multifunctional nanoparticles that combining bubble-induced mechanical effect with RNA interference are expected to be an effective NIR light responsive oncotherapy.
Vacuole integrity maintained by DUF300 proteins is required for brassinosteroid signaling regulation
(2018)
Brassinosteroid (BR) hormone signaling controls multiple processes during plant growth and development and is initiated at the plasma membrane through the receptor kinase BRASSINOSTEROID INSENSITIVE1 (BRI1) together with co-receptors such as BRI1-ASSOCIATED RECEPTOR KINASE1 (BAK1). BRI1 abundance is regulated by endosomal recycling and vacuolar targeting, but the role of vacuole-related proteins in BR receptor dynamics and BR responses remains elusive. Here, we show that the absence of two DUF300 domain-containing tonoplast proteins, LAZARUS1 (LAZ1) and LAZ1 HOMOLOG1 (LAZ1H1), causes vacuole morphology defects, growth inhibition, and constitutive activation of BR signaling. Intriguingly, tonoplast accumulation of BAK1 was substantially increased and appeared causally linked to enhanced BRI1 trafficking and degradation in laz1 laz1h1 plants. Since unrelated vacuole mutants exhibited normal BR responses, our findings indicate that DUF300 proteins play distinct roles in the regulation of BR signaling by maintaining vacuole integrity required to balance subcellular BAK1 pools and BR receptor distribution.
Negative interactions have been suggested as a major barrier for species arriving in a new habitat. More recently, positive interactions drew attention from community assembly theory and invasion science. The invasional meltdown hypothesis (IMH) introduced the idea that positive interactions among non-native species could facilitate one another’s invasion, even increasing their impact upon the native community. Many studies have addressed IMH, but with contrasting results, reflecting various types of evidence on a multitude of scales. Here we use the hierarchy-of-hypotheses (HoH) approach to differentiate key aspects of IMH, organizing and linking empirical studies to sub-hypotheses of IMH. We also assess the level of empirical support for each sub-hypothesis based on the evidence reported in the studies. We identified 150 studies addressing IMH. The majority of studies support IMH, but the evidence comes from studies with different aims and questions. Supporting studies at the community or ecosystem level are currently rare. Evidence is scarce for marine habitats and vertebrates. Few sub-hypotheses are questioned by more than 50% of the evaluated studies, indicating that non-native species do not affect each other’s survival, growth, reproduction, abundance, density or biomass in reciprocal A ↔ B interactions. With the HoH for IMH presented here, we can monitor progress in empirical tests and evidences of IMH. For instance, more tests at the community and ecosystem level are needed, as these are necessary to address the core of this hypothesis.