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Among the natural tetramic acids with a decalinoyl part, signermycin B is unique because it contains a cis‐decalin. In this paper, we demonstrate that the cis‐decalin section of signermycin B can be accessed by an anionic oxy‐Cope rearrangement. The substrate, a tricyclic dienol was prepared by an intramolecular Diels‐Alder reaction of a masked ortho‐benzoquinone, generated by oxidation of an α‐methoxyphenol in presence of cis‐2‐hexenol. After a superfluous bromine on the cycloadduct was removed, reaction of the tricyclic ketone with isopropenylmagnesium bromide led to the tricyclic trienol that underwent the oxy‐Cope rearrangement to a cis‐decalinone. While we could show, that introduction of the 4‐ethyl substituent (signermycin B numbering) is possible by enolate alkylation, the 4‐epi‐isomer was formed. [ABSTRACT FROM AUTHOR]

3-Methyl indanones are key synthetic building blocks for a variety of natural and useful synthetic compounds. Their synthesis is exceedingly difficult. Herein, we described a palladium (II) mediated intramolecular one-pot redox-relay cyclization of aromatic homoallylic alcohols to cyclic keto compounds. This catalytic system enabled direct conversion of homoallylic alcohols to corresponding indanones (3-methyl-1-indanones). Homoallylic alcohols were synthesized by reacting allyl magnesium bromide with corresponding aromatic aldehydes. The optimized reaction yielded up to 88% 3-methylindanones. Our findings enabled us to device a plausible mechanism for this one pot reaction. [ABSTRACT FROM AUTHOR]

Linguistic categories can impact visual perception. For instance, learning that two objects have different names can enhance their discriminability. Previous studies have identified a typical pattern of categorical perception, characterized by faster discrimination of stimuli from different categories, a neural mismatch response during early visual processing (100–200 ms), and effects restricted to the right visual field. However, it remains unclear whether language affects perception online or through long‐term changes to mental representations in memory. To address this, we tested the impact of newly learned object categories with and without memory consolidation during sleep. We replicated the canonical pattern of categorical perception for categories that underwent consolidation. Without consolidation, linguistic categories still influenced early visual processing but with distinct neural dynamics. Therefore, we found evidence of both transient and long‐term effects of language on perception and conclude that memory consolidation plays a crucial role in shaping how linguistic categories modulate perception. A one‐page Accessible Summary of this article in nontechnical language is freely available in the Supporting Information online and at https://oasis‐database.org. [ABSTRACT FROM AUTHOR]

Additive manufacturing enables the production of lattice structures, which have been proven to be a superior class of lightweight mechanical metamaterials whose specific stiffness can reach the theoretical limit of the upper Hashin–Shtrikman bound for isotropic cellular materials. To achieve isotropy, complex structures are required, which can be challenging in powder bed additive manufacturing, especially with regard to subsequent powder removal. The present study focuses on the Finite Element Method simulation of 2.5D anisotropic plate lattice metamaterials and the investigation of their lightweight potential. The intentional use of anisotropic structures allows the production of a cell architecture that is easily manufacturable via Laser Powder Bed Fusion (LPBF) while also enabling straightforward optimization for specific load cases. The work demonstrates that the considered anisotropic plate lattices exhibit high weight-specific stiffnesses, superior to those of honeycomb structures, and, simultaneously, a good de-powdering capability. A significant increase in stiffness and the associated surpassing of the upper Hashin–Shtrikman bound due to anisotropy is achievable by optimizing wall thicknesses depending on specific load cases. A stability analysis reveals that, in all lattice structures, plastic deformation is initiated before linear buckling occurs. An analysis of stress concentrations indicates that the introduction of radii at the plate intersections reduces stress peaks and simultaneously increases the weight-specific stiffnesses and thus the lightweight potential. Exemplary samples illustrate the feasibility of manufacturing the analyzed metamaterials within the LPBF process. [ABSTRACT FROM AUTHOR]

High-quality AI-generated portraits ("deepfakes") are becoming increasingly prevalent. Understanding the responses they evoke in perceivers is crucial in assessing their societal implications. Here we investigate the impact of the belief that depicted persons are real or deepfakes on psychological and neural measures of human face perception. Using EEG, we tracked participants' (N = 30) brain responses to real faces showing positive, neutral, and negative expressions, after being informed that they are either real or fake. Smiling faces marked as fake appeared less positive, as reflected in expression ratings, and induced slower evaluations. Whereas presumed real smiles elicited canonical emotion effects with differences relative to neutral faces in the P1 and N170 components (markers of early visual perception) and in the EPN component (indicative of reflexive emotional processing), presumed deepfake smiles showed none of these effects. Additionally, only smiles presumed as fake showed enhanced LPP activity compared to neutral faces, suggesting more effortful evaluation. Negative expressions induced typical emotion effects, whether considered real or fake. Our findings demonstrate a dampening effect on perceptual, emotional, and evaluative processing of presumed deepfake smiles, but not angry expressions, adding new specificity to the debate on the societal impact of AI-generated content. [ABSTRACT FROM AUTHOR]

High-quality AI-generated portraits ("deepfakes") are becoming increasingly prevalent. Understanding the responses they evoke in perceivers is crucial in assessing their societal implications. Here we investigate the impact of the belief that depicted persons are real or deepfakes on psychological and neural measures of human face perception. Using EEG, we tracked participants' (N = 30) brain responses to real faces showing positive, neutral, and negative expressions, after being informed that they are either real or fake. Smiling faces marked as fake appeared less positive, as reflected in expression ratings, and induced slower evaluations. Whereas presumed real smiles elicited canonical emotion effects with differences relative to neutral faces in the P1 and N170 components (markers of early visual perception) and in the EPN component (indicative of reflexive emotional processing), presumed deepfake smiles showed none of these effects. Additionally, only smiles presumed as fake showed enhanced LPP activity compared to neutral faces, suggesting more effortful evaluation. Negative expressions induced typical emotion effects, whether considered real or fake. Our findings demonstrate a dampening effect on perceptual, emotional, and evaluative processing of presumed deepfake smiles, but not angry expressions, adding new specificity to the debate on the societal impact of AI-generated content. [ABSTRACT FROM AUTHOR]

Gas transport in soils is usually assumed to be purely diffusive, although several studies have shown that non‐diffusive processes can significantly enhance soil gas transport. These processes include barometric air pressure changes, wind‐induced pressure pumping and static air pressure fields generated by wind interacting with obstacles. The associated pressure gradients in the soil can cause advective gas fluxes that are much larger than diffusive fluxes. However, the contributions of the respective transport processes are difficult to separate. We developed a large chamber system to simulate pressure fields and investigate their influence on soil gas transport. The chamber consists of four subspaces in which pressure is regulated by fans that blow air in or out of the chamber. With this setup, we conducted experiments with oscillating and static pressure fields. CO2 concentrations were measured along two soil profiles beneath the chamber. We found a significant relationship between static lateral pressure gradients and the change in the CO2 profiles (R2 = 0.53; p‐value <2e‐16). Even small pressure gradients between −1 and 1 Pa relative to ambient pressure resulted in an increase or decrease in CO2 concentrations of 8% on average in the upper soil, indicating advective flow of air in the pore space. Positive pressure gradients resulted in decreasing, negative pressure gradients in increasing CO2 concentrations. The concentration changes were probably caused by an advective flow field in the soil beneath the chamber generated by the pressure gradients. No effect of oscillating pressure fields was observed in this study. The results indicate that static lateral pressure gradients have a substantial impact on soil gas transport and therefore are an important driver of gas exchange between soil and atmosphere. Lateral pressure gradients in a comparable range can be induced under windy conditions when wind interacts with terrain features. They can also be caused by chambers used for flux measurements at high wind speed or by fans used for head‐space mixing within the chambers, which yields biased flux estimates. [ABSTRACT FROM AUTHOR]

We developed a route to rhodomyrtone analogs that feature different acyl groups at C7. Since electrophilic substitution reactions on the aryl part of the rhodomyrtone core led to C5 derivatives, the C5 position was blocked by a chlorine. Subsequent Duff type formylation followed by Grignard addition to the aldehyde group and oxidation gave various phenones. The benzyl protecting groups were removed by hydrogenation or boron tribromide. Some derivatives turned out to be quite active against multiple resistant Staphylococcus aureus strains and a rhodomyrtone resistant mutant (RomR). The chlorine at C5 seems to have a beneficial effect on the antibacterial activity. [ABSTRACT FROM AUTHOR]

The first regioselective syntheses of 1,2-thiaselenane-4-amine (TSA4) and 1,2-thiaselenane-5-amine (TSA5) are developed. Both are redox motifs with high value in chemical biology that until now were hindered by tedious synthesis. An aziridine intermediate and a kinetically controlled S-acylation were leveraged for regioselective chalcogen installations. Short, fast sequences were optimised with just one or two chromatographic steps that cheaply deliver these motifs on scale for high throughput inhibitor screening, and thus provide a robust methodology for assembling other selenenyl sulfides. [ABSTRACT FROM AUTHOR]

When two individuals share a task with a common goal, coordinating one's own and the other's actions is pivotal. Inhibition of one's own actions when it is the other's turn to act is assumed to play a crucial role in this process. For instance, in the joint Simon task, two individuals share a two-choice task such that one of them responds to one stimulus type and ignores the stimulus type to which the other responds. Because stimuli can either appear on one's own or on the other's side, stimulus location can conflict with stimulus identity, thus slowing response time. It has previously been shown that such conflict leads to a reduction of the detrimental effects of conflict on immediately upcoming trials both following own responses and even more so following the other's responses. This amplified trial-to-trial adjustment following the other's responses has been assumed to reflect the inhibition of own responses on the other's trials. The present study tested this hypothesis by comparing sequential trial-to-trial adjustments following correct responses and commission errors on which the inhibition of own responses has failed. As expected, adjustments were stronger following the other's correct responses than following own correct responses. Crucially, such amplification of sequential adjustment was not observed following own commission errors on the other's trials. This shows that amplification of sequential adjustments following the other's trials depend on successful inhibition of own responses on these trials and points to a crucial role of response inhibition for behavioral control in joint action. [ABSTRACT FROM AUTHOR]

The generation of the quaternary stereocenter at the C9 position of salvinorin A precursors by the Claisen rearrangement was investigated. The required allyl alcohol was prepared from a Wieland‐Miescher ketone using a known γ‐hydroxylation, reduction of the enone double bond, cyanohydrin formation, and elimination, yielding an unsaturated nitrile. A two‐step reduction led to the required allyl alcohol. The subsequent Johnson‐Claisen rearrangement provided a mixture of two diastereomeric 1,4‐unsaturated esters in a ratio of around 2.6 : 1. The major isomer could be converted to a key intermediate of the Hagiwara synthesis of salvinorin A. [ABSTRACT FROM AUTHOR]

Soils represent a major global source and sink of greenhouse gases (GHGs). Many studies of GHG fluxes between soil, plant and atmosphere rely on chamber measurements. Different chamber techniques have been developed over the last decades, each characterised by different requirements and limitations. In this manuscript, we focus on the non‐steady‐state technique which is widely used for manual measurements but also in automatic systems. Although the measurement method appears very simple, experience gained over the years shows that there are many details which have to be taken into account to obtain reliable measurement results. This manuscript aims to share lessons learnt and pass on experiences in order to assist the reader with possible questions or unexpected challenges, ranging from the planning of the design of studies and chambers to the practical handling of the chambers and the quality assurance of the gas and data analysis. This concise introduction refers to a more extensive Best Practice Guideline initiated by the Working Group Soil Gases (AG Bodengase) of the German Soil Science Society (Deutsche Bodenkundliche Gesellschaft). The intention was to collect and aggregate the expertise of different working groups in the research field. As a compendium, this Best Practice Guideline is intended to help both beginners and experts to meet the practical and theoretical challenges of measuring soil gas fluxes with non‐steady‐state chamber systems and to improve the quality of the individual flux measurements and thus entire GHG studies by reducing sources of uncertainty and error. [ABSTRACT FROM AUTHOR]

Humans are remarkably reliable in detecting errors in their behavior. Whereas error awareness has been assumed to emerge not until 200–400 ms after an error, the so‐called early error sensations refer to the subjective feeling of having detected an error even before the erroneous response was executed. Here, we collected electroencephalogram (EEG) to track how early error sensations are reflected in neural correlates of performance monitoring. Participants first had to perform a task, and then had to indicate whether an error has occurred and whether this error was detected before or after response execution. EEG results showed that early error sensations were associated with an earlier peak of the error‐related negativity (Ne/ERN), a component of error‐related brain activity that occurs briefly after the error response. This demonstrates that early error‐related activity influences metacognitive judgments on the time course of error awareness, and thus contributes to error awareness. Little is known about neural processes that contribute to how we become aware of self‐committed errors. Here, we show that humans frequently report error awareness even before response execution. This early error sensation was associated with an earlier peak in error‐related neural activity that has previously been assumed to precede error awareness. We propose that subjective timing of error awareness is aligned with the time course of early activity to synchronize actions with metacognitive consequences. [ABSTRACT FROM AUTHOR]

We present a strategy to the core structure of the alkaloid palhinine A passing through a 2,5-difunctionalized cyclohexenone. This enone was prepared by a domino Michael/aldol condensation sequence. An allylation reaction on the cyclohexenone followed by oxy-Cope rearrangement introduced an allyl group at C3. After the generation of an aldehyde function on the terminus of the C5 substituent, an intramolecular aldol reaction led to a bicyclo[2.2.2]octanone. The five-membered ring of the core structure could be established by an intramolecular nitrile oxide-alkene [3+2]-cycloaddition. Prior to this key transformation, the keto function was converted to an alkene and the allyl group to an oxime. [ABSTRACT FROM AUTHOR]

We investigated approaches to the xanthene part of schweinfurthin B. Starting from an exo‐methylene cyclohexanone, an organocuprate addition led to a cyclohexanone featuring a functionalized benzyl substituent in the 2‐position. Ring‐closing reactions to the tetrahydroxanthene core (formation of the central ring) were possible in moderate yield by attack of a phenolic oxygen function on the keto group. More effective was the cyclization to the xanthene core structure after conversion of the cyclohexanone to the exo‐methylene cyclohexane derivative and Lewis acid mediated addition of the phenolic OH to the double bond. In addition, we tried to form the xanthene ring system in a model study by cycloaddition reaction of a silyl enol ether with an ortho‐quinone methide. [ABSTRACT FROM AUTHOR]

Future emerging communication technologies are anticipated to fold into our surroundings, helping us get our noses off the smartphone screens and back into our environments. In doing so, they make us more (rather than less) present in the world around us. While 5G was supposed to be about the Internet of Everything, to be transformative 6G might be just about the opposite of Everything, that is, Nothing or, more technically, No Things. Building on the invisible-to-visible technology concept, this article explores how the full potential of multisensory extended reality (XR) experiences may be unleashed in Multiverse cross-reality environments. We exploit the convergence of artificial-intelligence-enhanced multi-access edge computing, intelligent mobile robots, and blockchain technologies to help realize the Internet of No Things as an important stepping stone toward ushering in the 6G post-smartphone era. In our experiments, we consider locally connected human-avatar/robot collectives and investigate our proposed extrasensory perception network, which integrates the three evolutionary mobile computing stages of ubiquitous, pervasive, and persuasive computing. As an illustrative example of advanced XR experiences, we study the delivery of sixth-sense perceptions that transverse the boundary between Multiverse realms in order to mimic the quantum realm. [ABSTRACT FROM AUTHOR]

The article reports on proposals from Salvadoran-Spanish philosopher Ignacio Ellacuría and Bishop of Rome Pope Francis for a new Global Civilisation. Topics include Ignacio Ellacuría had a prophetic presentiment of this change; he analyzed with clarity the crisis in the current global system, which he characterized as a civilisation of capital wealth; and Pope Francis, from the beginning of his pontificate, has shown his concern with the future of our planet and with a more just global order.

Streptosetin A belongs to the 3‐decalinoyltetramic acids. In contrast to most of other known natural products of this type, the decalin part features a β‐hydroxyketone subunit, making an intramolecular cycloaddition approach less suitable. We examined an approach where the decalin part would be fashioned by an intramolecular aldol addition. By using a Diels‐Alder reaction between the Rawal diene and a substituted methacrylate, a cyclohexanone was obtained. An organocuprate addition introduced the ethyl substituent before, the side chain was converted to an enal. However, contrary to our expectations, the aldol reaction led to the condensation product. Other routes to reach the key cyclohexanone were also investigated. [ABSTRACT FROM AUTHOR]

Novel 5G applications will require the processing of large amounts of computation-intensive, delay-sensitive tasks. Mobile devices, however, are subject to limited hardware resources (e.g., battery life, CPU, and storage) and therefore may fall short of satisfying the stringent latency requirements of complex tasks. To fill the gap between the increasing demands of computation-intensive, delay-sensitive tasks driven by emerging 5G applications and the availability of limited resources on smart mobile devices, we introduce our proposed architecture of multi-access computing (MEC) enabled Fiber–Wireless (FiWi) LTE enhanced HetNets, enabling the coexistence and cooperation between conventional (remote) cloud and MEC servers. After presenting our analytical framework to evaluate the energy-delay performance, we propose our distributed cooperative offloading strategy with the objective of minimizing the average response time for mobile users. [ABSTRACT FROM AUTHOR]

Contemporary resource constraint mobile devices face great challenges to execute computationally expensive tasks of low-latency Tactile Internet applications in a time-efficient manner. The so-called HART has emerged as a promising platform to address the burden of resource-limited mobile devices by allowing collaboration among humans, cloud agents, and robots for task execution. To facilitate a better task execution performance, dynamic task offloading onto suitable actors represents an important research problem, taking time-varying task, robot, and cloud agent properties into account. To tackle this open problem, this article first discusses characteristics, applications, and challenges of HART tasks. Next, this article investigates the problem of whether and where a HART task should be offloaded and presents a COTA strategy by taking task offloading gain and communication overhead into account. For HART-centric task offloading, this article leverages central cloud, mobile edge computing (MEC) servers, and multi-robot FiWi networks. Finally, numerical results are presented to examine the performance of the proposed COTA scheme over FiWi based Tactile Internet infrastructures. [ABSTRACT FROM AUTHOR]

Language is assumed to augment human cognition. But can language also affect basic mechanisms of perception, suggesting cognitive penetrability of perception? This idea is highly controversial: linguistic categorization may induce top-down effects on ongoing perceptual processing. Alternatively, such effects may not concern perception proper, but pre-perceptual shifts of attention or downstream processes, such as perceptual judgment. This study provides a critical test of these views by investigating categorical perception (CP) of novel objects in a balanced learning design, controlling for perceptual experience and low-level visual differences. To better understand which linguistic representations induce CP, we manipulated the type of information categories were based on: bare verbal labels, in-depth semantic knowledge, or the combined information from labels associated with semantic knowledge. We used event-related brain potentials (ERPs) derived from the EEG in a visual search task to localize CP effects at perceptual or pre/post-perceptual stages. The results replicated behavioral CP with facilitated visual search when target and distractors belonged to different linguistic categories. ERPs revealed CP effects in the P1 and N1 components, associated with early visual processing. Attentional selection, reflected in the N2, also was influenced by linguistic categories. The N2 and the N400, a measure of high-level semantic processing, were sensitive to the depth of semantic knowledge associated with objects. CP, however, did not differ between category types, suggesting that any linguistic categorization can lead to CP. The findings support cognitive penetrability of perception, with linguistic categories informing perceptual predictions down to the processing of low-level visual features. [ABSTRACT FROM AUTHOR]

The synthesis of a C1–C14 fragment of the macrolide antibiotic gulmirecin B through formation of the C7–C8 bond by addition of a vinyllithium intermediate to a C1–C7 aldehyde was investigated. This crucial coupling was successful with a vinyllithium reagent corresponding to a C8–C12 fragment. The C8–C12 vinyl bromide was prepared from l -malic acid. The C1–C7 aldehyde building block was synthesized from hex-5-enoic acid by using an Evans alkylation, a cross-metathesis, and an asymmetric dihydroxylation as key steps. [ABSTRACT FROM AUTHOR]

Highlights • The error-related pupil response was larger for more significant errors. • Single-trial pupil responses predicted better future performance for more significant errors. • The error-related negativity was larger for more significant errors. • Error-type specific autonomic arousal mechanisms promote post-error adjustments. Abstract Adjusting behavior following errors is essential for successful goal-directed performance. Error-related pupil dilation indicates increased autonomic arousal and has been shown to predict adaptive adjustments of post-error behavior. Because different types of errors may require different behavioral adjustments, we investigated whether this process is also sensitive to the evaluation of different types of errors. We used a four-choice flanker task where errors occur either by pressing a button associated with the distractors (flanker errors), or by pressing a button not associated with the stimulus at all (nonflanker errors). Flanker errors imply suboptimal selective attention to the target and are therefore of increased significance for successful performance. Pupil dilation was larger for flanker errors than nonflanker errors, and only pupil dilation on flanker errors predicted a decrease of error probability on the next trial. Moreover, the error-related negativity, an electrophysiological marker of early error monitoring in the medial frontal cortex, was larger on flanker errors anticipating the effect of error type on pupil dilation. These results show that error-related pupil dilation is sensitive to the type and significance of errors and correlates with adaptive behavioral adjustments accordingly. This suggests that mechanisms underlying error-related pupil dilation receive inputs from error evaluation mechanisms in the medial frontal cortex. [ABSTRACT FROM AUTHOR]

The optimization of human performance requires the continuous monitoring of behavioral conflicts. According to conflict monitoring theory, the dorsal anterior cingulate cortex registers response conflict which is reflected by two electrophysiological signatures, the N2 and the Ne/ERN. The theory assumes that, if a stimulus activates an incorrect response that competes with the correct response, pre-response conflict on correct trials (reflected by the N2) is enhanced but post-response conflict on error trials (reflected by the Ne/ERN) is reduced. Here, we asked whether response conflict depends on the number of competing incorrect responses activated by a stimulus, that is, whether the N2 is further enhanced and the Ne/ERN is further reduced if two incorrect responses are activated as compared to one. To this end, we used a modified flanker paradigm, in which the two flankers were associated either with the same incorrect response or with different incorrect responses. Our results indicate an increased N2 on correct trials and a reduced Ne/ERN on error trials in the latter as compared to the former condition. These results confirm central predictions of conflict monitoring theory and demonstrate that response conflict is directly related to the number of competing incorrect responses. • Activating more competing incorrect responses leads to a larger N2. • Activating more competing incorrect responses leads to smaller Ne/ERN. • Results provide support for conflict monitoring theory. [ABSTRACT FROM AUTHOR]

Can our native language influence what we consciously perceive? Although evidence that language modulates visual discrimination has been accumulating, little is known about the relation between language structure and consciousness. We employed electroencephalography and the attentional-blink paradigm, in which targets are often unnoticed. Native Greek speakers (N = 28), who distinguish categorically between light and dark shades of blue, showed boosted perception for this contrast compared with a verbally unmarked green contrast. Electrophysiological signatures of early visual processing predicted this behavioral advantage. German speakers (N = 29), who have only one category for light and dark shades of blue, showed no differences in perception between blue and green targets. The behavioral consequence of categorical perception was replicated with Russian speakers (N = 46), reproducing this novel finding. We conclude that linguistic enhancement of color contrasts provides targets with a head start in accessing visual consciousness. Our native language is thus one of the forces that determine what we consciously perceive. [ABSTRACT FROM AUTHOR]

We explored the possibility of attaching a side chain to a leiodermatolide fragment by forming the C18/C19 double bond via Julia/Kocienski olefination. This worked with a δ‐lactone surrogate, the meta‐anisole derivative 17 in reasonable yield to give the acyclic pentaene 32. However, due to problems during cleavage of the silyl ether at the 15‐OH, the corresponding macrolactone could not be obtained. Instead, it was possible to convert enal 31 by Tebbe olefination to pentaene 37. This compound could be converted to macrolactone 41 from where the side chain truncated leiodermatolide analogues 42 (9‐O‐carbamoyl) and 43 (7‐O‐carbamoyl) were obtained. Both isomers were moderately cytotoxic highlighting the importance of the side chain with the δ‐lactone. [ABSTRACT FROM AUTHOR]

The synthesis of seco acid 41 of the macrolactone part of 15- epi-exiguolide, containing a bis-pyran subunit and a trans double bond, is described. Key features of the synthetic strategy include a Feringa– Minnaard asymmetric organocuprate addition to unsaturated ester 17 to set the stereocenter at C15. The derived acid 8 (C9–C16 fragment) was ideally suited for combination with aldehyde 9 (C17–C21 fragment) via an aldol strategy leading to β-lactone 25 which upon thermal decarboxylation provided alkene 26. Chain extension led to propargylic alcohol 7. Treatment of 7 with a LAu+ catalyst promoted a Meyer–Schuster rearrangement to enone 30 that led to cis-tetrahydropyran 31 via intramolecular oxa-Michael reaction. The second pyran ring was prepared from alkoxy ketone 5 by reductive cyclization. The further steps toward macrolactone 43 were hampered by the epimeric mixture at C5. [ABSTRACT FROM AUTHOR]

Recently, edge computing has emerged as a promising computing paradigm to meet stringent quality-of-service requirements of an increasing number of latency-sensitive applications. The core principle of edge computing is to bring the capability of cloud computing in close proximity to mobile devices, sensors, actuators, connected things and end users, thereby supporting various types of services and applications at the network edge. In this article, we design capacity-centric FiWi broadband access networks enhanced with edge computing as well as resulting fiber backhaul sharing and computation offloading capabilities. More specifically, we introduce the concept of FiWi enhanced two-level edge computing at the access edge cloud and metro edge cloud. To guarantee low end-to-end latency, we propose a TDMA based polling scheme for resource management. Furthermore, given the vital importance of experimentally demonstrating the potential and practical limitations of edge computing, we develop an experimental testbed for edge computing across converged FiWi broadband access networks. The proof-ofconcept demonstration of the testbed is studied in terms of response time and response time efficiency of both edge clouds, including their respective energy consumption. [ABSTRACT FROM AUTHOR]

Errors in human behavior elicit a cascade of brain activity related to performance monitoring and error detection. Whereas the early error-related negativity (Ne/ERN) has been assumed to reflect a fast mismatch or prediction error signal in the medial frontal cortex, the later error positivity (Pe) is viewed as a correlate of conscious error processing. A still open question is whether these components represent two independent systems of error monitoring that rely on different types of information to detect an error. Here, we investigated the prediction that the Ne/ERN but not the Pe requires a representation of the correct response to emerge. To this end, we created a condition in which no information about the correct response was available while error detection was still possible. We hypothesized that a Pe, but no Ne/ERN should be obtained in this case. Participants had to classify targets but ignore flankers that were always associated with an incorrect response. Targets but not flankers were masked with varying target-masking intervals. Crucially, on some trials no target at all was presented, thus preventing the representation of a correct response and the emergence of an Ne/ERN. However, because flankers were easily visible and responses to the flankers were always incorrect, detection of these flanker errors was still possible. In line with predictions of a multiple-systems account, we observed a robust Pe in the absence of an Ne/ERN for these errors. Moreover, this Pe relied on the same neural activity as that on trials with a visible target, as revealed by multivariate pattern analysis. These findings demonstrate that the mechanisms reflected by the two components use different types of information to detect errors, providing evidence for independent systems of human error monitoring. [ABSTRACT FROM AUTHOR]

Investigations toward the synthesis of the 18-membered macrolactone biselyngbyolide B (2) from a C1-C13 and a C14-C23 fragment are described. As a key reaction in the synthesis of the C1-C13 fragment, we used an asymmetric propargylation of chiral vinylketene silyl N,O-acetal 12. Access to a C14-C23 fragment featuring a skipped diene and a sensitive allyl alcohol function was initially attempted via reductive fragmentation of a pyran template. However, this ring opening on iodide 32 with t-BuLi led to dienynol 33 with a 21Z double bond. With a silyl protecting group at 3-OH and by implementing an intramolecular Stille coupling for macrolactonization, the 21Z-isomer of biselyngbyolide B (47) was obtained. For preparation of a C14-C23 fragment with the 21E-configuration, a cross-coupling of vinylstannane 48 with 4-bromocrotonate (49) set the configuration of the two double bonds. Biselyngbyolide B (2) was then accessed by an intramolecular Heck coupling. In preliminary biological cytotoxicity assays, 2 turned out to be active, whereas the 21Z-isomer 47 was much less active. The 3-OMEM analogue 40 was devoid of activity. These results support the notion that the side chain with the correct configuration is relevant for binding to the Ca2+-ATPase and the biological activity. [ABSTRACT FROM AUTHOR]

Abstract: Pope Francis wants a reform of the church and he sees Archbishop Oscar Romero of El Salvador as a model bishop, one who smells like his sheep and who was fully committed to a poor church for the poor. Pope Francis and Archbishop Romero agree that the basis for church reform must be the gospel. As Jesus did not preach himself but the kingdom of God, the church must be at the service of the kingdom, she is the sacrament of the kingdom. The first addressees of the good news of the kingdom of God were the poor, so there is an intrinsic relationship between the church and the poor. Church reform means that the church becomes more like Jesus Christ serving the poor, the needy and the marginalized. There is an intrinsic relationship between church reform and the signs of the times. The Second Vatican Council established a new relationship between the church and the world. Of key importance for this are the signs of the times as signs of the presence and the plans of God in history. Archbishop Romero's deepest and most creative spiritual and theological insight is his association of the passion of the Salvadoran people with the suffering servant of God and the crucified Christ. He spoke of a crucified people. [ABSTRACT FROM AUTHOR]

Abstract: Quantifying and understanding fluxes of methane (CH4) and carbon dioxide (CO2) in natural soil–plant–atmosphere systems are crucial to predict global climate change. Wetland herbaceous species or tree species at waterlogged sites are known to emit large amounts of CH4. Upland forest soils are regarded as CH4 sinks and tree species like upland beech are not known to significantly emit CH4. Yet, data are scarce and this assumption needs to be tested. We combined measurements of soil–atmosphere and stem–atmosphere fluxes of CO2 and CH4, and soil gas profiles to assess the contribution of the different ecosystem compartments at two upland beech forest sites in Central Europe in a case study. Soil was a net CH4 sink at both sites, though emissions were detected consistently from beech stems at one site. Although stem emissions from beech stems were high compared to known fluxes from other upland tree species, they were substantially lower compared to the strong CH4 sink of the soil. Yet, we observed extraordinarily large CH4 emissions from one beech tree that was 140% of the CH4 sink of the soil. The soil gas profile at this tree indicated CH4 production at a soil depth > 0.3 m, despite the net uptake of CH4 consistently observed at the soil surface. Field soil assessment showed strong redoximorphic color patterns in the adjacent soil and supports this evaluation. We hypothesize that there is a transport link between the soil and stem via the root system representing a preferential transport mechanism for CH4 despite the fact that beech roots usually do not bear aerenchyma. The high mobility of gases requires a holistic view on the soil–plant–atmosphere system. Therefore, we recommend including field soil assessment and soil gas profiles measurements when investigating soil–atmosphere and stem–atmosphere fluxes to better understand the sources of gases and their transport mechanisms. [ABSTRACT FROM AUTHOR]

The ability to actively prepare for new tasks is crucial for achieving goal-directed behavior. The task-switching paradigm is frequently used to investigate this task-set reconfiguration. In the present study, we adopted a novel approach to identify a neural signature of reconfiguration in event-related potentials. Our method was to isolate neural correlates of reconfiguration failure and to use these correlates to reveal the time course of reconfiguration in task switches and task repetitions. We employed a task-switching paradigm in which two types of errors could be distinguished: task errors (the incorrect task was applied) and response errors (an incorrect response for the correct task was provided). Because differential activity between both error types distinguishes successful and failed reconfiguration, this activity could be used as a neural signature of the reconfiguration process. We found that, whereas reconfiguration takes place on task repetitions and task switches, it occurred earlier in the former than in the latter. Single-trial analysis revealed that the same activity predicted the amplitude of error-related brain activity, providing further support that this preparatory activity reflects reconfiguration. Our results implicate that reconfiguration is not switch-specific but that task switches and task repetitions differ with respect to the time course of reconfiguration. Furthermore, this study demonstrates that considering neural correlates of failure is a promising approach to link cognitive mechanisms to specific neural processes. [ABSTRACT FROM AUTHOR]

Naturally produced by microbial processes in soil, nitrous oxide (N2O) is an important greenhouse gas contributing to climate change. Accordingly, there is a need to accurately quantify the capability of forest ecosystems to exchange N2O with the atmosphere. While N2O emissions from soils have been well studied, trees have so far been overlooked in N2O inventories. Here, we show that stems of mature beech trees (Fagus sylvatica) may act as a substantial sink of N2O from the atmosphere under conditions of soils consuming N2O. Consistent consumption of N2O by all stems investigated (ranging between −2.4 and −3.8 µg m−2 h−1) is a novel finding in contrast to current studies presenting trees as N2O emitters. To understand these fluxes, N2O exchange of photoautotrophic organisms associated with beech bark (lichens, mosses and algae) was quantified under laboratory conditions. All these organisms were net N2O sinks at full rehydration and temperature of 25 °C. The consumption rates were comparable to stem consumption rates measured under field conditions. Cryptogamic stem covers could be a relevant sink of N2O in European beech forests. [ABSTRACT FROM AUTHOR]

Early error monitoring in the medial frontal cortex enables error detection and the evaluation of error significance, which helps prioritize adaptive control. This ability has been assumed to be independent from central capacity, a limited pool of resources assumed to be involved in cognitive control. The present study investigated whether error evaluation depends on central capacity by measuring the error-related negativity (Ne/ERN) in a flanker paradigm while working memory load was varied on two levels. We used a four-choice flanker paradigm in which participants had to classify targets while ignoring flankers. Errors could be due to responding either to the flankers (flanker errors) or to none of the stimulus elements (nonflanker errors). With low load, the Ne/ERN was larger for flanker errors than for nonflanker errors-an effect that has previously been interpreted as reflecting differential significance of these error types. With high load, no such effect of error type on the Ne/ERN was observable. Our findings suggest that working memory load does not impair the generation of an Ne/ERN per se but rather impairs the evaluation of error significance. They demonstrate that error monitoring is composed of capacity-dependent and capacity-independent mechanisms. [ABSTRACT FROM AUTHOR]

The polycyclic natural product lingzhiol [(±)-1] was synthesized from dimethoxytetralone 8 via cyclization of an intermediate benzylic radical, generated from spiroepoxide 14, onto an alkynyl substituent generating tetracyclic compound 13 with an exocyclic double bond. After oxidative cleavage of the double bond of 13 and reduction of the keto function of 23, the correct diastereomer, 12-syn, was converted to lingzhiol (1) via known steps. In a similar manner, lingzhiol analogue 39 was synthesized from 5-methoxy-1-tetralone (27). [ABSTRACT FROM AUTHOR]

Errors in speeded choice tasks can lead to post-error adjustments both on the behavioral and on the neural level. There is an ongoing debate whether such adjustments result from adaptive processes that serve to optimize performance or whether they reflect interference from error monitoring or attentional orientation. The present study aimed at identifying adaptive adjustments in a two-stage visual search task, in which participants had to select and subsequently identify a target stimulus presented to the left or right visual hemifield. Target selection and identification can be measured by two distinct event-related potentials, the N2pc and the SPCN. Using a decoder analysis based on multivariate pattern analysis, we were able to isolate the processing stages related to error sources and post-error adjustments. Whereas errors were linked to deviations in the N2pc and the SPCN, only for the N2pc we identified a post-error adjustment, which exhibits key features of source-specific adaptivity. While errors were associated with an increased N2pc, post-error adjustments consisted in an N2pc decrease. We interpret this as an adaptive adjustment of target selection to prevent errors due to disproportionate processing of the task-irrelevant target location. Our study thus provides evidence for adaptive post-error adjustments in visual search. [ABSTRACT FROM AUTHOR]

Multi-tenancy is one of the key features of cloud computing, which provides scalability and economic benefits to the end-users and service providers by sharing the same cloud platform and its underlying infrastructure with the isolation of shared network and compute resources. However, resource management in the context of multi-tenant cloud computing is becoming one of the most complex task due to the inherent heterogeneity and resource isolation. This paper proposes a novel cloud-based workflow scheduling (CWSA) policy for compute-intensive workflow applications in multi-tenant cloud computing environments, which helps minimize the overall workflow completion time, tardiness, cost of execution of the workflows, and utilize idle resources of cloud effectively. The proposed algorithm is compared with the state-of-the-art algorithms, i.e., First Come First Served (FCFS), EASY Backfilling, and Minimum Completion Time (MCT) scheduling policies to evaluate the performance. Further, a proof-of-concept experiment of real-world scientific workflow applications is performed to demonstrate the scalability of the CWSA, which verifies the effectiveness of the proposed solution. The simulation results show that the proposed scheduling policy improves the workflow performance and outperforms the aforementioned alternative scheduling policies under typical deployment scenarios. [ABSTRACT FROM PUBLISHER]

Detecting behavioral errors is critical for optimizing performance. Here, we tested whether error monitoring is enhanced in emotional task contexts, and whether this enhancement depends on processing internal affective states. Event-related potentials were recorded in individuals with low and high levels of alexithymia-that is, individuals with difficulties identifying and describing their feelings. We administered a face word Stroop paradigm (Egner, Etkin, Gale, & Hirsch, 2008) in which the task was to classify emotional faces either with respect to their expression (happy or fearful; emotional task set) or with respect to their gender (female or male; neutral task set). The error-related negativity, a marker of rapid error monitoring, was enhanced in individuals with low alexithymia when they adopted the emotional task set. By contrast, individuals with high alexithymia did not show such an enhancement. Moreover, in the high-alexithymia group, the difference in the error-related negativities between the emotional and neutral task sets correlated negatively with difficulties identifying their own feelings, as measured by the Toronto Alexithymia Scale. These results show that error-monitoring activity is stronger in emotional task contexts and that this enhancement depends on processing internal affective states. [ABSTRACT FROM AUTHOR]

The macrocyclic core (35) of the marine natural product leiodermatolide (1) was synthesized from two key fragments, vinyl iodide 23 (C1-C11 part) and vinyl stannane 31 (C12-C18 part). A Stille coupling led to conjugated Z,Z-diene 32. The derived seco acid 34 was cyclized using a Yamaguchi macrolactonization. Key steps in the assembly of vinyl iodide 23 were a Paterson aldol reaction, and a Kumada coupling on a triflate derivative to create the C4-C5 trisubstituted double bond. The two stereocenters in fragment 31 were established by a Marshall-Tamaru reaction. The longest linear sequence comprises 20 steps. [ABSTRACT FROM AUTHOR]

Cyclooctatetraene derivatives (COTR) with two carbocycles attached to the central ring have been used as dianionic ligands for the synthesis of double-decker complexes of the type [(COTR)2M]-. Two ligand derivatives were combined with diamagnetic Y3+ and with the five paramagnetic lanthanide ions from Tb3+ to Tm3+. The more complex substitution pattern in comparison to the parent ligand COT or the popular bis-trimethylsilyl derivative allows a sufficient number of signals to be obtained for a comprehensive paramagnetic NMR analysis. The anionic double-decker complexes gave well-resolved NMR spectra where almost all 1H and 13C NMR signals could be detected and assigned. With these data, it was possible to separate the two main contributions to the paramagnetic shift (pseudocontact and Fermi contact shifts, respectively) and to determine the magnetic anisotropy of the lanthanide ions in their ligand fields. We can easily obtain the sign and the magnitude of the anisotropy of the magnetic susceptibility, which is itself strongly related to the energy barrier for spin reversal in single-molecule magnets. Our results confirm that Bleaney factors are inadequate descriptors for magnetic anisotropy in these lanthanide complexes. [ABSTRACT FROM AUTHOR]

The advent of commercially available remote-presence robots may be the precursor of an age of technological convergence, where important tasks of our everyday life will be increasingly done by robots. A very low roundtrip latency in conjunction with ultra-high reliability and essentially guaranteed availability for control communications has the potential to move today?s mobile broadband experience into the new world of the Tactile Internet for a race with (rather than against) machines. To facilitate a better understanding of the Tactile Internet, this article first elaborates on the commonalities and subtle differences between the Tactile Internet and the Internet of Things and 5G vision. After briefly reviewing its anticipated impact on society and infrastructure requirements, we then provide an up-to-date survey of recent progress and enabling technologies proposed for the Tactile Internet. Given that scaling up research in the area of future wired and wireless access networks will be essential for the Tactile Internet, we pay particular attention to the latency and reliability performance gains of fiber-wireless (FiWi) enhanced LTE-Advanced heterogeneous networks and their role for emerging cloudlets, mobile-edge computing, and cloud robotics. Finally, we conclude by outlining remaining open challenges for the Tactile Internet. [ABSTRACT FROM AUTHOR]

Violations of outcome expectancies have been proposed to account for error-related brain activity in the medial prefrontal cortex. The present study investigated whether early error monitoring processes are sensitive only to the expectancy of errors, or whether these processes also evaluate the significance of errors. To this end, we considered the error-related negativity (Ne/ERN), an electrophysiological marker of early error monitoring, in a modified flanker task in which errors could occur because participants responded to the flankers instead of the target (flanker error) or because a response unrelated to the stimulus was given (nonflanker error). By manipulating the onset of the flankers relative to the target, we manipulated two variables: the probability (and thus the expectancy) of flanker errors and the proportion of significant attention errors among each error type. Contrary to the predictions of outcome expectancy accounts, we found that the Ne/ERN was larger for flanker errors than for nonflanker errors only in the condition in which flanker errors were particularly frequent. Consistent with the error significance account, however, Ne/ERN amplitude mirrored the estimated proportion of significant attention errors as estimated by multinomial modeling. These results provide support for the idea that early performance monitoring as reflected by the Ne/ERN involves an evaluation of error significance. [ABSTRACT FROM AUTHOR]

Two novel routes to the acylphloroglucinol rhodomyrtone ( 1 ) which has antibiotic properties are presented. In the first route an ortho -quinone methide, generated from dioxaborinine 23 , is reacted with syncarpic acid ( 10 ) leading to xanthenedione 25 . Cleavage of the methyl ether functions led to the known rhodomyrtone precursor 16 . In the second route the bis-ester derivative 28 of trihydroxybenzaldehyde 26 is condensed with syncarpic acid ( 10 ) to give tricyclic hemiacetal 29 . Acetalization and cuprate addition to the enone function led to bis-ester 32 which gave rhodomyrtone ( 1 ) by TiCl 4 -induced regioselective Fries rearrangement. [ABSTRACT FROM AUTHOR]

Azo compounds are efficient electron acceptors. Upon one‐electron reduction they generally isomerize forming the thermodynamically most stable radical anion. Herein we show that the size of the central ring in 1,2‐diazocines and diazonines has a ruling influence on the configuration of the one‐electron reduced species. Markedly, diazonines, which bear a central nine membered heterocycle, show light‐induced E/Z isomerization, but retain the configuration of the diazene N=N moiety upon one‐electron reduction. Accordingly, E/Z isomerization is not induced by reduction. [ABSTRACT FROM AUTHOR]

Accumulating evidence suggests that visual perception and, in particular, visual discrimination, can be influenced by verbal category boundaries. One issue that still awaits systematic investigation is the specific influence of semantic contents of verbal categories on categorical perception (CP). We tackled this issue with a learning paradigm in which initially unfamiliar, yet realistic objects were associated with either bare labels lacking explicit semantic content or labels that were accompanied by enriched semantic information about the specific meaning of the label. Two to three days after learning, the EEG was recorded while participants performed a lateralized oddball task. Newly acquired verbal category boundaries modulated low-level aspects of visual perception as early as 100–150 ms after stimulus onset, suggesting a genuine influence of language on perception. Importantly, this effect was not further influenced by enriched semantic category information, suggesting that bare labels and the associated minimal and predominantly perceptual information are sufficient for CP. Distinct effects of semantic knowledge independent of category boundaries were found subsequently, starting at about 200 ms, possibly reflecting selective attention to semantically meaningful visual features. [ABSTRACT FROM AUTHOR]

An experimental mechanistic study of the gold(I)-catalyzed hydroamination shows the formation of conformationally flexible auro-iminium salts Au-Im, which originate from the protonation of a vinyl gold species. Rotation around the CCAu bond is the reason for the loss of stereospecificity of protodeauration, which explains the stereochemical result of the Stradiotto reaction. The ambiguity about inner or outer sphere mechanism is thus resolved in favor of the outer sphere mechanism. [ABSTRACT FROM AUTHOR]