Ultrahigh field 27Al{1H} 2D correlation NMR experiments demonstrate that at least two framework Al(IV) sites with hydroxyl groups can exist in acidic zeolite catalysts in their dehydrated and ...catalytically active states. In addition to the known Al(IV) at the framework bridging acid site (BAS), a new site created by a second tetrahedral Al atom and its hydroxyl group protons in zeolite HZSM-5 is clearly resolved at 35.2 T field strengths, enabled by recently developed series-connected hybrid (SCH) magnet technology. Coupled with computational modeling, extensive 27Al MQMAS experiments at multiple field strengths, and 1H MAS NMR experiments, these data indicate that this second tetrahedrally coordinated Al site (denoted Al(IV)-2) experiences an increased chemical shift and unique quadrupolar parameters relative to the BAS in both dehydrated and hydrated states. These new experimental data, supported by computational and catalytic reaction work, indicate that the second site arises from partially bonded framework (SiO)4−n -Al(OH) n species that significantly increase catalyst reactivity in benzene hydride-transfer and n-hexane cracking reactions. Al(IV)-2 sites result either from framework crystallization defects or from incomplete postsynthetic hydrolysis of a framework Al, prior to the formation of extraframework Al. Populations of this second acidic proton site created by the Al(IV)-2 species are shown to be controlled via postsynthetic catalyst treatments, should be general to different catalyst structures, and significantly enhance catalyst reactivity in the cited probe reactions when they are present. The results herein communicate the highest magnetic field strength data on active zeolite catalyst structures to date and enable for the first time the detection of Al and H association on a dry HZSM-5 catalyst, i.e., under conditions representative of typical end-use processes.
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Definitions of Solitude in Everyday Life Weinstein, Netta; Hansen, Heather; Nguyen, Thuy-vy
Personality & social psychology bulletin,
12/2023, Volume:
49, Issue:
12
Journal Article
Peer reviewed
Open access
What does it mean to be in solitude? Researchers building this nascent field are learning much about the potential affordances of solitude, but lack an agreed-upon definition or set of definitions. ...Arriving at that meaning is crucial to forming a solid foundation for studies that use both naturalistic and laboratory designs to explore outcomes of solitude. This study identified themes from semi-structured interviews with adults aged 19 to 80 from diverse backgrounds. We concluded that solitude is a state in which the dominant relationship is with the self. If not physically alone, people in solitude are mentally distanced from others and away from active technology-mediated interactions. Complete solitude involves both physical separation and inner focus, but solitude is best defined through a taxonomy that recognizes physical separation and internal focus as independent, sufficient characteristics. An internal focus benefits from (but is not defined by) balancing solitude with social time, quiet, and choice.
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Possible routes for intra‐cluster bond formation (ICBF) in protonated serine dimers have been studied. We found no evidence of ICBF following low energy collision‐induced dissociation (in ...correspondence with previous works), however, we do observe clear evidence for ICBF following photon absorption in the 4.6–14 eV range. Moreover, the comparison of photon‐induced dissociation measurements of the protonated serine dimer to those of a protonated serine dipeptide provides evidence that ICBF, in this case, involves peptide bond formation (PBF). The experimental results are supported by ab initio molecular dynamics and exploration of several excited state potential energy surfaces, unraveling a pathway for PBF following photon absorption. The combination of experiments and theory provides insight into the PBF mechanisms in clusters of amino acids, and reveals the importance of electronic excited states reached upon UV/VUV light excitation.
While collision induced dissociation of protonated serine dimers leads only to cluster breakup, clear evidence that irradiation by Vacuum UV (PID) light leads to intra‐cluster bond formation is presented. Furthermore, comparison with the PID of serine dipeptides suggests that peptide bond formation is involved in the process.
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In this research, we showed that solitude generally has a deactivation effect on people’s affective experiences, decreasing both positive and negative high-arousal affects. In Study 1, we found that ...the deactivation effect occurred when people were alone, but not when they were with another person. Study 2 showed that this deactivation effect did not depend on whether or not the person was engaged in an activity such as reading when alone. In Study 3, high-arousal positive affect did not drop in a solitude condition in which participants specifically engaged in positive thinking or when they actively chose what to think about. Finally, in Study 4, we found that solitude could lead to relaxation and reduced stress when individuals actively chose to be alone. This research thus shed light on solitude effects in the past literature, and on people’s experiences when alone and the different factors that moderate these effects.
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Within the solitude literature, two discrete constructs reflect different perspectives on how time spent alone is motivated. Self-determined motivation for solitude reflects wanting time alone to ...find enjoyment and gain meaningful benefits from it, whereas preference for solitude concerns wanting time for oneself over others' company regardless of reasons for why time alone is wanted. We investigated two personality characteristics: introversion from Big-Five personality theory and dispositional autonomy from self-determination theory. In two diary studies university students completed personality measures and reported about their experiences with time spent alone over a period of seven days. Across both studies, contrary to popular belief that introverts spend time alone because they enjoy it, results showed no evidence that introversion is predictive of either preference or motivation for solitude. Dispositional autonomy-the tendency to regulate from a place of self-congruence, interest, and lack of pressure-consistently predicted self-determined motivation for solitude but was unrelated to preference for solitude. These findings provided evidence supporting the link between valuing time spent alone with individual differences in the capacity to self-regulate in choiceful and authentic way.
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Automatic cell type identification is essential to alleviate a key bottleneck in scRNA-seq data analysis. While most existing classification tools show good sensitivity and specificity, they often ...fail to adequately not-classify cells that are missing in the used reference. Additionally, many tools do not scale to the continuously increasing size of current scRNA-seq datasets. Therefore, additional tools are needed to solve these challenges.
scAnnotatR is a novel R package that provides a complete framework to classify cells in scRNA-seq datasets using pre-trained classifiers. It supports both Seurat and Bioconductor's SingleCellExperiment and is thereby compatible with the vast majority of R-based analysis workflows. scAnnotatR uses hierarchically organised SVMs to distinguish a specific cell type versus all others. It shows comparable or even superior accuracy, sensitivity and specificity compared to existing tools while being able to not-classify unknown cell types. Moreover, scAnnotatR is the only of the best performing tools able to process datasets containing more than 600,000 cells.
scAnnotatR is freely available on GitHub ( https://github.com/grisslab/scAnnotatR ) and through Bioconductor (from version 3.14). It is consistently among the best performing tools in terms of classification accuracy while scaling to the largest datasets.
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A simple metal-free method for the synthesis of quinazolinones from commercially available 2-nitrobenzyl alcohols and tetrahydroisoquinolines is developed. The reaction conditions were tolerant of an ...array of functionalities such as halogen, tertiary amine, protected alcohol, and ester groups. Under nearly identical conditions, quinazolinethiones were obtained in the presence of elemental sulfur and suitable mediators.
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This research explored arousal levels as a motivating factor for solitude-seeking. We hypothesized that solitude becomes more desirable when high-arousal emotions were heightened and individual ...differences in extraversion and neuroticism would moderate this pattern.
We tracked individuals' hourly experiences throughout a day. We assessed their high-arousal positive (e.g., excitement) and negative emotions (e.g., tension), whether they were alone or with others, and their preferred situation at the time of the signal. We gathered 4338 surveys from 362 participants, with 103 participants completing all hourly surveys.
Preference for and incidence of solitude changed throughout the day. Contrary to our hypotheses, lagged analyses did not indicate high-arousal emotions predicting reports of being alone an hour later. However, individuals were more likely to express a preference for solitude while experiencing high-arousal negative emotions, and less so while experiencing positive emotions. Younger individuals display stronger preference for solitude during experiences of high-arousal negative emotions. Extraversion and neuroticism did not moderate these patterns.
The results highlight the distinctive appeal of solitude as a space for young adults to deal with negative emotions. We discussed how these findings are connected to existing literature and implications for future research.
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Identification of species of the dinoflagellate genus Ostreopsis is difficult because several species have been poorly described, others misidentified in the literature, and the type species, ...O. siamensis, has not been described by contemporary taxonomic methods. In the present study, it is argued that Ostreopsis sp. 6 as described by previous authors is similar to the type species, and we offer an emended description of O. siamensis by LM, SEM, and molecular analyses of nuclear LSU and ITS rDNA based on material collected a few hundred kilometers from the type locality in the Gulf of Thailand and along the Vietnamese east coast. Ostreopsis siamensis is genetically different from the species reported as O. cf. siamensis in the literature and the latter should be described as a separate species. It is also concluded that with the poor knowledge of the morphological variability of many species of Ostreopsis, O. siamensis may not be distinguished from other similar‐sized species by its morphological features, and hence molecular data are needed for reliable identification. The species Ostreopsis lenticularis and Ostreopsis cf. ovata were also found and described.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
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