bluuebunny/crossref_metadata_2025 huggingface dataset:
CD9 Is Associated with Leukemia Inhibitory Factor-mediated Maintenance of Embryonic Stem Cells
Authors: Oka Masahiro , Tagoku Kenichi , Russell Thomas L. , Nakano Yuka , Hamazaki Takashi , Meyer Edwin M. , Yokota Takashi , Terada Naohiro
Published: July 2002

Mouse embryonic stem (ES) cells can proliferate indefinitely in an undifferentiated state in the presence of leukemia inhibitory factor (LIF), or differentiate into all three germ layers upon removal of this factor. To determine cellular factors associated with self-renewal of undifferentiated ES cells, we used polymerase chain reaction-assisted cDNA subtraction to screen genes that are expressed in undifferentiated ES cells and down-regulated after incubating these cells in a differentiation medium without LIF for 48 h. The mRNA expression of a tetraspanin transmembrane protein, CD9, was high in undifferentiated ES cells and decreased shortly after cell differentiation. An immunohistochemical analysis confirmed that plasma membrane-associated CD9 was expressed in undifferentiated ES cells but low in the differentiated cells. Addition of LIF to differentiating ES cells reinduced mRNA expression of CD9, and CD9 expression was accompanied with a reappearance of undifferentiated ES cells. Furthermore, activation of STAT3 induced the expression of CD9, indicating the LIF/STAT3 pathway is critical for maintaining CD9 expression. Finally, addition of anti-CD9 antibody blocked ES cell colony formation and reduced cell viability. These results indicate that CD9 may play a role in LIF-mediated maintenance of undifferentiated ES cells.
Automated genome sequence analysis and annotation.
Authors: Andrade M A , Brown N P , Leroy C , Hoersch S , de Daruvar A , Reich C , Franchini A , Tamames J , Valencia A , Ouzounis C , Sander C
Published: July 2002

MOTIVATION: Large-scale genome projects generate a rapidly increasing number of sequences, most of them biochemically uncharacterized. Research in bioinformatics contributes to the development of methods for the computational characterization of these sequences. However, the installation and application of these methods require experience and are time consuming. RESULTS: We present here an automatic system for preliminary functional annotation of protein sequences that has been applied to the analysis of sets of sequences from complete genomes, both to refine overall performance and to make new discoveries comparable to those made by human experts. The GeneQuiz system includes a Web-based browser that allows examination of the evidence leading to an automatic annotation and offers additional information, views of the results, and links to biological databases that complement the automatic analysis. System structure and operating principles concerning the use of multiple sequence databases, underlying sequence analysis tools, lexical analyses of database annotations and decision criteria for functional assignments are detailed. The system makes automatic quality assessments of results based on prior experience with the underlying sequence analysis tools; overall error rates in functional assignment are estimated at 2.5-5% for cases annotated with highest reliability ('clear' cases). Sources of over-interpretation of results are discussed with proposals for improvement. A conservative definition for reporting 'new findings' that takes account of database maturity is presented along with examples of possible kinds of discoveries (new function, family and superfamily) made by the system. System performance in relation to sequence database coverage, database dynamics and database search methods is analysed, demonstrating the inherent advantages of an integrated automatic approach using multiple databases and search methods applied in an objective and repeatable manner. AVAILABILITY: The GeneQuiz system is publicly available for analysis of protein sequences through a Web server at http://www.sander.ebi.ac. uk/gqsrv/submit
CpGProD: identifying CpG islands associated with transcription
start sites in large genomic mammalian sequences
Authors: Ponger Loı̈c , Mouchiroud Dominique
Published: July 2002

Results: CpGProD is an application for identifying mammalian promoter regions associated with CpG islands in large genomic sequences. Although it is strictly dedicated to this particular promoter class corresponding to ≈50% of the genes, CpGProD exhibits a higher sensitivity and specificity than other tools used for promoter prediction. Notably, CpGProD uses different parameters according to species (human, mouse) studied. Moreover, CpGProD predicts the promoter orientation on the DNA strand.

Availability: http://pbil.univ-lyon1.fr/software/cpgprod.html

Supplementary information: http://pbil.univ-lyon1.fr/software/cpgprod.html

Contact: ponger@biomserv.univ-lyon1.fr

* To whom correspondence should be addressed.
p8 is critical for tumour development induced by rasV12 mutated protein and E1A oncogene
Authors: Vasseur Sophie , Hoffmeister Albrecht , Garcia Stéphane , Bagnis Claude , Dagorn Jean‐Charles , Iovanna Juan Lucio
Published: July 2002

The p8 protein is involved in the cellular stress response of many tissues. Because p8 is overexpressed in many cancers, we investigated whether its expression was required for tumour development. Mouse embryo fibroblasts (MEFs) from p8+/+ and p8−/− animals were transformed with the pBabe‐rasV12/E1A retroviral vector, which expresses both the rasV12 mutated protein and the E1A oncogene. As expected, transformed p8+/+ MEFs could form colonies in soft agar. However, transformed p8−/− MEFs could not. In addition, subcutaneous or intraperitoneal injections of transformed p8+/+ MEFs always led to tumour formation in nude mice, but, again, no tumour was observed with transformed p8−/− MEFs. However, restoring p8 expression in transformed p8−/− MEFs before injection led to tumour formation. In the tumours, p8 expression was induced during tumour development. It was concluded that p8 expression in transformed MEFs is necessary for tumour formation, suggesting that the stress‐response mechanisms governed by p8 are required for tumour establishment.
PECAM‐1 shedding during apoptosis generates a membrane‐anchored truncated molecule with unique signaling characteristics
Authors: ILAN NETA , MOHSENIN AMIR , CHEUNG LAWRENCE , MADRI JOSEPH A.
Published: July 2002

Shedding of cell surface molecules, including growth factor receptors, provides a mechanism by which cells regulate signal transduction events. Here we show that platelet‐endothelial cell adhesion molecule (PECAM)‐1 is shed from the endothelial cell surface during apoptosis and accumulates in the culture medium as a ~100 kDa soluble protein. The cleavage mediating the shedding is matrix metalloproteinase (MMP) dependent, as GM6001, a broad‐spectrum MMP inhibitor, inhibits PECAM‐1 accumulation in the culture medium in a dose‐responsive manner. In addition to the 100 kDa soluble fragment, PECAM‐1 cleavage generates the formation of a truncated (Tr.) ~28 kDa molecule, composed of the transmembrane and the cytoplasmic PECAM‐1 domains. Transfections of the full‐length (Fl) and the Tr. PECAM‐1 gene constructs into endothelial and nonendothelial cells were performed. We found 1) significantly more γ‐catenin and SHP‐2 bound to the truncated than to the full‐length PECAM‐1;2) stable expression of the truncated PECAM‐1 in SW480 colon carcinoma cells resulted in a dramatic decrease in cell proliferation, whereas expression of comparable levels of the full‐length PECAM‐1 had no effect;3) the decrease observed in cell proliferation is due, in part, to an increase in programmed cell death (apoptosis) and correlated with continuous caspase 8 cleavage and p38/JNKphosphorylation. These results support the intimate involvement of PECAM‐1 in signal transduction cascades and also suggest that caspase substrates (e.g., PECAM‐1) may possess distinct and unique functions on cleavage.—Ilan, N., Mohsenin, A., Cheung, L., Madri, J. A. PECAM‐1 shedding during apoptosis generates a membrane‐anchored truncated molecule with unique signaling characteristics. FASEB J. 15, 362‐372 (2001)
Nuclear magnetic resonance monitoring of treatment and prediction of outcome in multiple sclerosis
Authors: Miller David H. , Thompson Alan J.
Published: July 2002

Magnetic resonance (MR) techniques provide an objective, sensitive and quantitative assessment of the evolving pathology in multiple sclerosis. There is an increasing definition of the pathological specificity of newer techniques, and more robust correlations with clinical evolution are emerging. As the pathophysiological basis of
in vivo
nuclear MR signal abnormalities is further elucidated, it is likely that the importance of MR as a tool to monitor new therapies will increase.
Symbiotic fungal associations in ‘lower’ land plants
Authors: Read D. J. , Duckett J. G. , Francis R. , Ligrone R. , Russell A.
Published: July 2002

An analysis of the current state of knowledge of symbiotic fungal associations in ‘lower’ plants is provided. Three fungal phyla, the Zygomycota, Ascomycota and Basidiomycota, are involved in forming these associations, each producing a distinctive suite of structural features in well–defined groups of ‘lower’ plants. Among the ‘lower’ plants only mosses andEquisetumappear to lack one or other of these types of association. The salient features of the symbioses produced by each fungal group are described and the relationships between these associations and those formed by the same or related fungi in ‘higher’ plants are discussed. Particular consideration is given to the question of the extent to which root–fungus associations in ‘lower’ plants are analogous to ‘mycorrhizas’ of ‘higher’ plants and the need for analysis of the functional attributes of these symbioses is stressed.

Zygomycetous fungi colonize a wide range of extant lower land plants (hornworts, many hepatics, lycopods, Ophioglossales, Psilotales and Gleicheniaceae), where they often produce structures analogous to those seen in the vesicular–arbuscular (VA) mycorrhizas of higher plants, which are formed by members of the order Glomales. A preponderance of associations of this kind is in accordance with palaeobotanical and molecular evidence indicating that glomalean fungi produced the archetypal symbioses with the first plants to emerge on to land.

It is shown, probably for the first time, that glomalean fungi forming typical VA mycorrhiza with a higher plant (Plantago lanceolata) can colonize a thalloid liverwort (Pellia epiphylla), producing arbuscules and vesicles in the hepatic. The extent to which these associations, which are structurally analogous to mycorrhizas, have similar functions remains to be evaluated.

Ascomycetous associations are found in a relatively small number of families of leafy liverworts. The structural features of the fungal colonization of rhizoids and underground axes of these plants are similar to those seen in mycorrhizal associations of ericaceous plants likeVaccinium. Cross inoculation experiments have confirmed that a typical mycorrhizal endophyte of ericaceous plants,Hymenoscyphus ericae, will form associations in liverworts which are structurally identical to those seen in nature. Again, the functional significance of these associations remains to be examined.

Some members of the Jungermanniales and Metzgeriales form associations with basidiomycetous fungi. These produce intracellular coils of hyphae, which are similar to the pelotons seen in orchid mycorrhizas, which also involve basidiomycetes. The fungal associates of the autotrophicAneuraand of its heterotrophic relativeCryptothallus mirabilishave been isolated. In the latter case it has been shown that the fungal symbiont is an ectomycorrhizal associate ofBetula, suggesting that the apparently obligate nature of the association between the hepatic andBetulain nature is based upon requirement for this particular heterotroph.
The T-box factor MLS-1 acts as a molecular switch during specification of nonstriated muscle in C. elegans
Authors: Kostas Stephen A. , Fire Andrew
Published: July 2002

We have isolated mutations in a gene mls-1 that is required for proper specification of nonstriated muscle fates inCaenorhabditis elegans. Loss of MLS-1 activity causes uterine muscle precursors to forego their normal fates, instead differentiating as vulval muscles. We have cloned mls-1 and shown that the product is a member of the T-box family of transcriptional regulators. MLS-1 acts as a cell fate determinant in that ectopic expression can transform other cell types to uterine muscle precursors. Uterine muscle patterning is executed by regulation of MLS-1 at several different levels. The mls-1 promoter is activated by the C. elegans orthologs of Twist and Daughterless, but is only active in a subset of the lineage where these two transcription factors are present. mls-1 activity also appears to be regulated by posttranscriptional processes, as expression occurs in both uterine and vulval muscle precursors.
Subcellular localization of the yeast proteome
Authors: Kumar Anuj , Agarwal Seema , Heyman John A. , Matson Sandra , Heidtman Matthew , Piccirillo Stacy , Umansky Lara , Drawid Amar , Jansen Ronald , Liu Yang , Cheung Kei-Hoi , Miller Perry , Gerstein Mark , Roeder G. Shirleen , Snyder Michael
Published: July 2002

Protein localization data are a valuable information resource helpful in elucidating eukaryotic protein function. Here, we report the first proteome-scale analysis of protein localization within any eukaryote. Using directed topoisomerase I-mediated cloning strategies and genome-wide transposon mutagenesis, we have epitope-tagged 60% of theSaccharomyces cerevisiaeproteome. By high-throughput immunolocalization of tagged gene products, we have determined the subcellular localization of 2744 yeast proteins. Extrapolating these data through a computational algorithm employing Bayesian formalism, we define the yeast localizome (the subcellular distribution of all 6100 yeast proteins). We estimate the yeast proteome to encompass ∼5100 soluble proteins and >1000 transmembrane proteins. Our results indicate that 47% of yeast proteins are cytoplasmic, 13% mitochondrial, 13% exocytic (including proteins of the endoplasmic reticulum and secretory vesicles), and 27% nuclear/nucleolar. A subset of nuclear proteins was further analyzed by immunolocalization using surface-spread preparations of meiotic chromosomes. Of these proteins, 38% were found associated with chromosomal DNA. As determined from phenotypic analyses of nuclear proteins, 34% are essential for spore viability—a percentage nearly twice as great as that observed for the proteome as a whole. In total, this study presents experimentally derived localization data for 955 proteins of previously unknown function: nearly half of all functionally uncharacterized proteins in yeast. To facilitate access to these data, we provide a searchable database featuring 2900 fluorescent micrographs athttp://ygac.med.yale.edu.
Measurements of low‐energy (d,n) reactions for BNCT
Authors: Colonna N. , Beaulieu L. , Phair L. , Wozniak G. J. , Moretto L. G. , Chu W. T. , Ludewigt B. A.
Published: July 2002

Neutron yields and energy spectra have been measured for various deuteron‐induced reactions at low energy. Neutrons of energy keV emitted in the N, and N reactions at MeV were detected at five angles by means of liquid scintillator detectors. While low‐energy neutrons were observed in all studied reactions, only N is characterized by a relatively large yield with spectral features potentially interesting for an accelerator‐based neutron source for BNCT.
A parametric error analysis of the backward integration method for reverberation time estimation
Authors: Morgan Dennis R.
Published: July 2002

Backward integration of a room impulse response has long been used in room acoustics for the estimation of reverberation time. However, the inevitable noise floor limits the minimum level of the measured impulse response, thereby leading to errors. This paper shows how the error is influenced by the selection of truncation time and evaluation range. A general guideline that emerges from this study is to truncate the measured impulse response at the knee where the main decay slope intersects the noise floor, then measure the slope of the backward integrated truncated impulse response down to a level about 5 dB above the noise floor.
Expression of emotional–motivational connotations with a one-word utterance
Authors: Leinonen Lea , Hiltunen Tapio , Linnankoski Ilkka , Laakso Maija-Liisa
Published: July 2002

The expression of “naming,” “commanding,” “angry,” “frightened,” “pleading,” “astonished,” “satisfied,” “admiring,” “scornful,” and “sad” was studied with the word [saara] spoken by 12 subjects. Using the same connotations, the 120 utterances were categorized by 73 listeners. Most samples were agreed on by 50%–99% of the judges. Most samples of “astonished,” “angry,” “frightened,” and “commanding” were judged as intended, while “pleading” was often confused with “sad,” and “content” with “admiring.” Acoustic differences between the categories were examined for F0, duration, and sound pressure; spectral features of [aa] were visualized with the self-organizing map of Kohonen. Most intraspeaker variation of mean F0, F0 range, sound pressure, and duration took place during the [aa] segment. Peak sound pressure, mean F0, and spectral energy distribution of [aa] differentiated among “commanding,” “angry,” “frightened,” “naming,” and “sad.” Specific intonations of the [aa] segment were encountered for “astonished,” “scornful,” and “pleading.” The best-conveyed “admiring” samples were distinguished from “content” by spectral cues for a breathy voice quality.
Pilot experiment for the acquisition of marine sediment properties via small scale tomography system
Authors: Rapids Brian , Nye Tom , Yamamoto Tokuo
Published: July 2002

A 3-D high resolution crosswell acoustic tomography system was designed and tested in a shallow water environment. This system makes use of a damped least-squared inversion technique and is used to construct compressional wave velocity images from measured travel time data. Use of singular value decomposition allowed checks of the linear inversion confirming the validity of the modeled environment. It is shown that when the ratio of width to depth of the cross section is about unity or smaller and the domain has not been overparametrized the inverted image model has sufficiently good figures of merit in resolution and variance to visualize small variations in the magnitude compressional velocity field.
Solar/heat-driven thermoacoustic engine
Authors: Chen Reh-lin , Garrett Steven L.
Published: July 2002

With its abundance and cleanliness, solar energy has been harnessed to generate power using various techniques. A thermoacoustic engine is described which was built, instrumented, and tested to demonstrate use of solar power to generate acoustic power. Sunlight is collected using a 3-ft-diam acrylic Fresnel lens and focused on one end of a ceramic ‘‘stack.’’ This engine has a total length of 40 cm and resonates at around 420 Hz. To permit testing on the abundant cloudy days in Pennsylvania, an electrical heater was also built and installed to provide a reliable thermal energy source for indoor measurements. Experimental results are in reasonable agreement with a DeltaE model. When running in solar mode, as a 1/4 wavelength open end resonator, the measured acoustic SPL can reach 120 dB easily at 1 m away from the open end on a clear day. The onset of sound generation can be achieved even with a 1-ft-diam Fresnel lens. While an impressive demonstration in terms of sound output, despite modest efficiency, real solar energy conversion will be improved with inert gas mixtures at higher pressures. [Work supported by ONR, lens provided by G. W. Swift.]
Gap detection as a measure of electrode interaction in cochlear implants
Authors: Hanekom Johan J. , Shannon Robert V.
Published: July 2002

Gap detection thresholds were measured as an indication of the amount of interaction between electrodes in a cochlear implant. The hypothesis in this study was as follows: when the two stimuli that bound the gap stimulate the same electrode, and thus the same neural population, the gap detection threshold will be short. As two stimuli are presented to two electrodes that are more widely separated, the amount of neural overlap of the two stimuli decreases, the stimuli sound more dissimilar, and the gap thresholds increase. Gap detection thresholds can thus be used to infer the amount of overlap in neural populations stimulated by two electrodes. Three users of the Nucleus cochlear implant participated in this study. Gap detection thresholds were measured as a function of the distance between the two electrode pairs and as a function of the spacing between the two electrodes of a bipolar pair (i.e., using different modes of stimulation). The results indicate that measuring gap detection thresholds may provide an estimate of the amount of electrode interaction. Gap detection thresholds were a function of the physical separation of the electrode pairs used for the two stimuli that bound the gap. Lower gap thresholds were observed when the two electrode pairs were closely spaced, and gap thresholds increased as the separation increased, resulting in a “psychophysical tuning curve” as a function of electrode separation. The sharpness of tuning varied across subjects, and for the three subjects in this study, the tuning was generally sharper for the subjects with better speech recognition. The data also indicate that increasing the separation between active and reference electrodes has limited effect on spatial selectivity (or tuning) as measured perceptually.
Powder diffraction data of Ba0.5Sr0.5TiO(C2O4)2·5H2O
Authors: Vanhoyland G. , Hoste S. , Van Bael M. K. , Mullens J. , Van Poucke L. C.
Published: July 2002

Ba0.5Sr0.5TiO(C2O4)2·5H2O, which is used as a precursor for Ba0.5Sr0.5TiO3 (BST), has been characterized by X-ray powder diffraction. In accordance with the known structure of BaTiO(C2O4)2·yH2O, the crystal system was found to be monoclinic with unit cell parameters: a=1.3965(1) nm, b=1.3811(2) nm, c=1.3306(2) nm, and β=92.15(1)°. The space group is P21/n, ρ=2.292(2) g cm−3, and Z=8.
Hearing Loss and Dementia Prevalence in Older Adults in the US
Authors: Huang Alison R. , Jiang Kening , Lin Frank R. , Deal Jennifer A. , Reed Nicholas S.
Published: January 2023

This study assesses the association of audiometric hearing loss and hearing aid use with dementia among community-dwelling older US Medicare beneficiaries.
Belief in COVID‐19 misinformation: Hopeful claims are rated as truer
Authors: Stone Alexandria R. , Marsh Elizabeth J.
Published: January 2023

Misinformation surrounding COVID‐19 spread rapidly and widely, posing a significant threat to public health. Here, we examined whether some types of misinformation are more believable than others, to the extent that they offer people hope in uncertain times. An initial group of subjects rated a series of COVID‐19 misinformation statements for whether each made them feel more or less hopeful (if true). Based on these ratings, we selected two sets of misinformation that differed in their average rated hopefulness; the two sets did not differ in word length or reading ease. In two studies, people rated their belief in each statement. Results from both studies revealed that people rated the more hopeful misinformation (e.g., COVID cures and prevention methods) as truer than less hopeful misinformation (e.g., transmission vectors). These findings are consistent with a motivated reasoning account of misinformation acceptance.
Birth Outcomes and Rehospitalizations Among Pregnant Women With Rheumatoid Arthritis and Systemic Lupus Erythematosus and Their Offspring
Authors: Singh Namrata , Sabo Julianna , Crane Deborah A. , Doody David R. , Schiff Melissa A. , Mueller Beth A.
Published: January 2023

Objective

To compare obstetric/birth outcomes and rehospitalization among women with and without rheumatoid arthritis (RA) or systemic lupus erythematosus (SLE) and their infants.

Methods

This population‐based retrospective cohort study identified women with RA (n = 1,223) and SLE (n = 1,354) and unexposed women with singleton births 1987–2014 in Washington State in linked vital hospital discharge records. Outcomes, including cause‐specific hospitalizations <2 years postpartum, were compared by estimating adjusted relative risks (RRs) and cause‐specific rehospitalization hazard ratios (HRs) with 95% confidence intervals (95% CIs).

Results

We observed increased risks of several adverse outcomes; RRs were often greatest for SLE. Women with RA/SLE more often required rehospitalization, most notably at <6 months postpartum (RA: 4% versus 2%; RR 2.22 [95% CI 1.62–3.04]; SLE: 6% versus 2%; RR 2.78 [95% CI 2.15–3.59]). Maternal postpartum rehospitalization was greatest for musculoskeletal conditions (RA: HR 19.1 [95% CI 13.6–26.8]; SLE: HR 29.8 [95% CI 22.1–40.1]). Infants of women with SLE more often had malformations (9% versus 6%; RR 1.46 [95% CI 1.21–1.75]), and increased mortality at <2 years (RR 2.11 [95% CI 1.21–3.67]). Infants of women with SLE also experienced more frequent rehospitalizations in their first year of life.

Conclusion

Women with RA or SLE and their infants experienced adverse outcomes, particularly infants of women with SLE. Maternal/infant rehospitalization was more common; most marked in the early months postpartum. Close follow‐up during these time periods is crucial to minimize adverse outcomes.
Live Cell Lineage Tracing of Dormant Cancer Cells
Authors: Kim Hyuna , Wirasaputra Anna , Mohammadi Farnaz , Kundu Aritra Nath , Esteves Jennifer A. E. , Heiser Laura M. , Meyer Aaron S. , Peyton Shelly R.
Published: January 2023

Breast cancer is a leading cause of global cancer‐related deaths, and metastasis is the overwhelming culprit of poor patient prognosis. The most nefarious aspect of metastasis is dormancy, a prolonged period between primary tumor resection and relapse. Current therapies are insufficient at killing dormant cells; thus, they can remain quiescent in the body for decades until eventually undergoing a phenotypic switch, resulting in metastases that are more adaptable and drug resistant. Unfortunately, dormancy has few in vitro models, largely because lab‐derived cell lines are highly proliferative. Existing models address tumor dormancy, not cellular dormancy, because tracking individual cells is technically challenging. To combat this problem, a live cell lineage approach to find and track individual dormant cells, distinguishing them from proliferative and dying cells over multiple days, is adapted. This approach is applied across a range of different in vitro microenvironments. This approach reveals that the proportion of cells that exhibit long‐term quiescence is regulated by both cell intrinsic and extrinsic factors, with the most dormant cells found in 3D collagen gels. This paper envisions that this approach will prove useful to biologists and bioengineers in the dormancy community to identify, quantify, and study dormant tumor cells.
Transition Metal‐Catalyzed Dearomative Vinylation of Electron Rich Benzenes, Naphthalenes and Indoles with Alkynes
Authors: Yang Yongjie , Jiang Kai , Zeng Guohui , Yin Biaolin
Published: January 2023

Dearomatization reactions are among the most efficient chemical processes, combining atom economy, stereospecificity and the ability to generate molecular complexity in a single step. Dearomative vinylation reactions provide a synthetic connection between readily available, simple aromatic starting materials and more unsaturated alkynes. The last decade has witnessed a steady increase in the development of transition metal‐catalyzed dearomative vinylation methods of electron rich aromatic compounds with alkynes, providing new synthetic approaches to high‐value building blocks and natural products. This review aims to serve as a comprehensive reference for work in transition metal‐catalyzed dearomative vinylation reactions of electron rich aromatic compounds with alkynes.

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The effect of skin color variation on 25(OH)D concentration in Polish children
Authors: Iliescu Florin Mircea , Pruszkowska‐Przybylska Paulina , Sitek Aneta , Żądzińska Elżbieta
Published: January 2023

Objectives

Skin color is a classic example of a visible human trait that varies widely among and between human populations; it has evolved finely balancing photoprotection and 25(OH)D (vitamin D) synthesis as opposing selection forces. While the health effects of vitamin D deficiency in Northern European populations are profound, we are yet to accurately characterize the evolutionary relationship between vitamin D requirements and skin color diversity.

Materials and Methods

This study explored this relation among a cohort of 170 children from central Poland considering season of measurement and socioeconomic status (SES). Alongside completed questionnaires, saliva was collected and the level of 25(OH)D was assessed using an enzyme‐linked immunosorbent assay kit; furthermore, a Dermaspectrometer was used to measure skin color by recording the Melanin Index (MI).

Results

First, 25(OH)D concentration or skin color variation are not significantly different between boys and girls; second, 25(OH)D concentration is lower in late autumn than in spring, while skin color (MI) is darker in autumn; crucially, we found significant association between MI and 25(OH)D concentration: higher MI is significantly associated with lower 25(OH)D levels only in boys measured in autumn, and not in spring.

Conclusions

These results shed light on the factors affecting 25(OH)D concentration and MI variation in a cohort of Polish children: they offer an evolutionary perspective on the potential role of vitamin D as a driver of skin color diversity while informing a key public health debate.
Selective Separation of Lithium, Magnesium and Calcium using 4‐Phosphoryl Pyrazolones as pH‐Regulated Receptors
Authors: Zhang Jianfeng , Tanjedrew Narisara , Wenzel Marco , Royla Philipp , Du Hao , Kiatisevi Supavadee , Lindoy Leonard F. , Weigand Jan J.
Published: January 2023

Ensuring continuous and sustainable lithium supply requires the development of highly efficient separation processes such as LLE (liquid‐liquid extraction) for both primary sources and certain waste streams. In this work, 4‐phosphoryl pyrazolones are used in an efficient pH‐controlled stepwise separation of Li+ from Ca2+, Mg2+, Na+ and K+. The factors affecting LLE process, such as the substitution pattern of the extractant, diluent/water distribution, co‐ligand, pH, and speciation of the metal complexes involved, were systematically investigated. The maximum extraction efficiency of Li+ at pH 6.0 was 94 % when Mg2+ and Ca2+ were previously separated at pH<5.0, proving that the separation of these ions is possible by simply modulating the pH of the aqueous phase. Our study points a way to separation of lithium from acid brine or from spent lithium ion battery leaching solutions, which supports the future supply of lithium in a more environmentally friendly and sustainable manner.
Supramolecular Engineering of Cathode Materials for Aqueous Zinc‐ion Energy Storage Devices: Novel Benzothiadiazole Functionalized Two‐Dimensional Olefin‐Linked COFs
Authors: Peng Haijun , Huang Senhe , Montes‐García Verónica , Pakulski Dawid , Guo Haipeng , Richard Fanny , Zhuang Xiaodong , Samorì Paolo , Ciesielski Artur
Published: January 2023

Two‐dimensional covalent organic frameworks (COFs) have emerged as promising materials for energy storage applications exhibiting enhanced electrochemical performance. While most of the reported organic cathode materials for zinc‐ion batteries use carbonyl groups as electrochemically‐active sites, their high hydrophilicity in aqueous electrolytes represents a critical drawback. Herein, we report a novel and structurally robust olefin‐linked COF‐TMT‐BT synthesized via the aldol condensation between 2,4,6‐trimethyl‐1,3,5‐triazine (TMT) and 4,4′‐(benzothiadiazole‐4,7‐diyl)dibenzaldehyde (BT), where benzothiadiazole units are explored as novel electrochemically‐active groups. Our COF‐TMT‐BT exhibits an outstanding Zn2+storage capability, delivering a state‐of‐the‐art capacity of 283.5 mAh g−1at 0.1 A g−1. Computational and experimental analyses reveal that the charge‐storage mechanism in COF‐TMT‐BT electrodes is based on the supramolecularly engineered and reversible Zn2+coordination by the benzothiadiazole units.
Discovery of Potent and Exquisitely Selective Inhibitors of Kinase CK1 with Tunable Isoform Selectivity
Authors: Němec Václav , Khirsariya Prashant , Janovská Pavlína , Moyano Paula Martín , Maier Lukáš , Procházková Petra , Kebková Pavlína , Gybel' Tomáš , Berger Benedict‐Tilman , Chaikuad Apirat , Reinecke Maria , Kuster Bernhard , Knapp Stefan , Bryja Vítězslav , Paruch Kamil
Published: January 2023

Casein kinases 1 (CK1) are key signaling molecules that have emerged recently as attractive therapeutic targets in particular for the treatment of hematological malignancies. Herein, we report the identification of a new class of potent and highly selective inhibitors of CK1α, δ and ϵ. Based on their optimal in vitro and in vivo profiles and their exclusive selectivity, MU1250, MU1500 and MU1742 were selected as quality chemical probes for those CK1 isoforms. At proper concentrations, MU1250 and MU1500 allow for specific targeting of CK1δ or dual inhibition of CK1δ/ϵ in cells. The compound MU1742 also efficiently inhibits CK1α and, to our knowledge, represents the first potent and highly selective inhibitor of this enzyme. In addition, we demonstrate that the central 1H‐pyrrolo[2,3‐b]pyridine‐imidazole pharmacophore can be used as the basis of highly selective inhibitors of other therapeutically relevant protein kinases, e.g. p38α, as exemplified by the compound MU1299.
Highly Enantioselective Construction of Multifunctional Silicon‐Stereogenic Silacycles by Asymmetric Enamine Catalysis
Authors: Zhang Xue‐Xin , Gao Yang , Zhang Yan‐Xue , Zhou Jian , Yu Jin‐Sheng
Published: January 2023

We report the first highly enantioselective construction of silicon‐stereocenters by asymmetric enamine catalysis. An unprecedented desymmetric intramolecular aldolization of prochiral siladials was thus developed for the facile access of multifunctional silicon‐stereogenic silacycles in high to excellent enantioselectivity. With an enal moiety, these adducts could be readily elaborated for the diverse synthesis of silicon‐stereogenic compounds, and for late‐stage modification.
Rational Design of Covalent Organic Frameworks as Gas Diffusion Layers for Multi‐atmosphere Lithium‐Air Batteries
Authors: Li Xing , Zhang Kun , Li Zhen , Yan Youguo , Yuan Yijia , Ma Li , Xie Keyu , Ping Loh Kian
Published: January 2023

Non‐aqueous Li‐air batteries, despite their high energy density and low cost, have not been deployed practically due to their instability in ambient air, where moisture causes parasitic reactions and shortens their life drastically. Here, we demonstrate the rational design of nanoporous covalent organic frameworks (COFs) as effective gas diffusion layers (GDLs) to address this constraint. The COF GDLs, with a tailor‐made pore size of ≈1.4 nm and superhydrophobicity, can limit the intrusion of organic electrolytes and moisture into the gas diffusion channels, enabling high capacity, fast kinetics, and excellent stability of the Li‐air batteries. Moreover, we achieve multi‐atmosphere Li‐air batteries, which can stably cycle under open ambient air (relative humidity up to 95 %) and even in various atmospheres with looping oxygen, humid air, and carbon dioxide. The design principles of our COF GDLs can be universally applied in energy storage and electrochemical systems using organic electrolytes.
Springtail‐inspired Light‐driven Soft Jumping Robots Based on Liquid Crystal Elastomers with Monolithic Three‐leaf Panel Fold Structure
Authors: Hu Jun , Nie Zhenzhou , Wang Meng , Liu Zhiyang , Huang Shuai , Yang Hong
Published: January 2023

Jump is an important form of motion that enables animals to escape from predators, increase their range of activities, and better adapt to the environment. Inspired by springtails, we describe a light‐driven soft jumping robot based on a double‐folded liquid crystal elastomer (LCE) ribbon actuator with a monolithic three‐leaf panel fold structure. This robot can achieve remarkable jumping height, jumping distance, and maximum take‐off velocity, of up to 87 body length (BL), 65 BL, and 930 BL s−1, respectively, under near‐infrared light irradiation. Further, it is possible to control the height, distance, and direction of jump by changing the size and crease angle of the double‐folded LCE ribbon actuators. These robots can efficiently jump over obstacles and can jump continuously, even in complex environments. Our simple design strategy improves the performance of jumping actuators and we expect it to have a wide‐ranging impact on the strength, continuity, and adaptability of future soft robots.
Generation of FeIV=O and its Contribution to Fenton‐Like Reactions on a Single‐Atom Iron−N−C Catalyst
Authors: Cheng Cheng , Ren Wei , Miao Fei , Chen Xuantong , Chen Xiaoxiao , Zhang Hui
Published: January 2023

Generating FeIV=O on single‐atom catalysts by Fenton‐like reaction has been established for water treatment; however, the FeIV=O generation pathway and oxidation behavior remain obscure. Employing an Fe−N−C catalyst with a typical Fe−N4moiety to activate peroxymonosulfate (PMS), we demonstrate that generating FeIV=O is mediated by an Fe−N−C−PMS* complex—a well‐recognized nonradical species for induction of electron‐transfer oxidation—and we determined that adjacent Fe sites with a specific Fe1−Fe1distance are required. After the Fe atoms with an Fe1‐Fe1distance <4 Å are PMS‐saturated, Fe−N−C−PMS* formed on Fe sites with an Fe1‐Fe1distance of 4–5 Å can coordinate with the adjacent FeII−N4, forming an inter‐complex with enhanced charge transfer to produce FeIV=O. FeIV=O enables the Fenton‐like system to efficiently oxidize various pollutants in a substrate‐specific, pH‐tolerant, and sustainable manner, where its prominent contribution manifests for pollutants with higher one‐electron oxidation potential.
Peri‐operative management of a patient with an ectodermal dysplasia (Rapp–Hodgkin) syndrome
Authors: Marialva J. , Lopes L. , Moura F. , Cardoso H. , Cruz L.
Published: January 2023

We present the case of a 41‐year‐old man with Rapp–Hodgkin syndrome who underwent nasal septum deviation surgery under general anaesthesia. This syndrome is rare, with approximately 70 cases reported worldwide. It is one of a group of ectodermal dysplasia syndromes and results from the aberrant development of ectoderm during fetal development. Some of the clinical features may affect anaesthetic management. The most important considerations are potentially difficult airway management, the need for meticulous temperature control, and the importance of skin protection. This case was uneventful, but as there are few case reports on the management of patients with ectodermal dysplasia syndromes undergoing anaesthesia this report contributes useful knowledge. The pathogenesis and clinical features of Rapp–Hodgkin syndrome and the anaesthetic management for this patient are described.
Finite‐time event‐triggered control for a class of cascade switched affine nonlinear systems
Authors: Hu Hongsheng , Huang Shipei
Published: January 2023

This paper is concerned with the finite‐time boundedness (FTB) problem of a class of cascade switched affine nonlinear systems. In order to avoid unnecessary waste of network communication and Zeno behavior, a dynamical event‐triggered scheme is proposed, which is more general than some existing event‐triggered schemes with a common parameter matrix. By using the average dwell time method and multiple Lyapunov function technologies, sufficient conditions for the existence of controller gains are first proposed such that the closed‐loop system is finite‐time bounded with a finite‐time disturbance attenuation performance. It is also proved that the Zeno phenomenon is excluded. Finally, a numerical example is given to illustrate the feasibility and effectiveness of the proposed method.
Prep your campus for the opportunity to offer Pell Grants to incarcerated students
Authors: Sutton Halley
Published: January 2023

The U.S. Department of Education announced it will reinstate Pell Grant eligibility for incarcerated students, starting with the 2023–2024 academic year, reversing a 1994 decision that barred incarcerated people from accessing Pell funds. That decision came with the passage of the Free Application for Federal Student Aid Simplification Act and will go into effect July 1, 2023. Findings by the Prison Policy Institute found that restoring Pell Grant access could make approximately 463,000 people eligible for free college courses.
Therapists' experiences of “internet exposure” in the therapeutic relationship: An interpretative phenomenological analysis
Authors: Baraniuk Stacey , Lodge Rosemary
Published: January 2023

Background

As social media continues to grow in popularity, many people have become accustomed to publishing information about themselves and others on the web. In this context, it is arguably harder than ever for therapists to keep their personal and professional lives separate. There is little research to help practitioners navigate this.

Aims

This research aimed at investigating the effect on the therapist and the therapeutic relationship in cases where clients obtained personal information about their therapist online and subsequently disclosed that information during a session.

Methodology

Semistructured interviews were conducted with six participants and analysed using interpretative phenomenological analysis (IPA). Participants were interviewed twice, with the second interview taking place 8 weeks after the first. Participants were qualified mental health professionals who had experience of a client disclosing personal information about them that had been obtained online.

Findings

Four superordinate themes emerged: (1) tension in peacetime, (2) breach of defences, (3) weapons and (4) the aftermath: renegotiation with client and self. These represent the struggle experienced by participants and follow the journey from pre to postdisclosure. The analysis identified feelings of vulnerability and shame, which made it difficult to navigate the therapeutic relationship.

Conclusion

The findings suggest that the experience can positively impact the therapeutic relationship, despite challenges. Nonetheless, fear continues to cloud this topic, prompting an avoidance among therapists, supervisors, training organisations and professional bodies. The implications of this study are not concerned with preventing the encounter but rather with preparing for the eventuality.
Synthetic Multienzyme Assemblies for Natural Product Biosynthesis
Authors: Liu Min , Wang Yue , Jiang Hao , Han Yongxu , Xia Jiang
Published: January 2023

In nature, enzymes that catalyze sequential reactions are often assembled as clusters or complexes. The formation of multienzyme complexes, or metabolons, brings the enzyme active sites into proximity to promote intermediate transfer, decrease intermediate leakage, and streamline the metabolic flux towards the desired products. We and others have developed synthetic versions of metabolons through various strategies to enhance the catalytic rates for synthesizing valuable chemicals inside microbes. Synthetic multienzyme complexes range from static enzyme nanostructures to dynamic enzyme coacervates. Enzyme complexation optimizes the metabolic fluxes inside microbes, increases the product titer, and supplies the field with high‐yield microbe strains that are amenable to large‐scale fermentation. Enzyme complexes constructed inside microbial cells can be separated as independent entities and catalyze biosynthetic reactions ex vivo; such a feature gains these complexes another name, “synthetic organelles” – new subcellular entities with independent structures and functions. Still, the field is seeking new strategies to better balance dynamicity and confinement and to achieve finer control of local compartmentalization in the cells, as the natural multienzyme complexes do. Industrial applications of synthetic multienzyme complexes for the large‐scale production of valuable chemicals are yet to be realized. This review focuses on synthetic multienzyme complexes that are constructed and function inside microbial cells.
Suicide left ventricle following protamine: A case report
Authors: Erdem Saliha , An Sin Yeong , McAlister Courtney A. , Basra Sukhdeep S.
Published: January 2023

A patient with severe aortic stenosis and left ventricular hypertrophy underwent a transcatheter aortic valve replacement. The patient's blood pressure significantly dropped after protamine administration. A diagnosis of suicide left ventricle post‐valve replacement was made. The diagnosis and management of the protamine reaction are detailed. This case highlights the need to slowly infuse protamine sulfate and monitor for adverse events.
Effect of the Discharging Flap on Particle Separation in a Cyclone
Authors: Misiulia Dzmitry , Nedumaran Praveen Kumar , Antonyuk Sergiy
Published: January 2023

The flow field, pressure drop, and separation efficiency of an industrial cyclone separator were computationally investigated using the Reynolds stress model simulations. The effects of the flapper valve on the static pressure drop, cut size, and slope of the grade efficiency curve were revealed. For that, the cyclone was simulated in three operation regimes, when the flapper valve is open, closed, and without the flapper valve. The results showed that a flapper valve increases the cyclone cut size by 3.4 % when it is in the position “closed” and by 11.4 % when it is in the position “open”. The slope of the grade efficiency curve increases when a valve is switched to the position “open” but the static pressure drop increases by 4.8 % when a flapper valve is in the position “closed”.
Liquefaction of Waste Rendering Fat Using Iron‐Containing Catalysts
Authors: Babor Martin , Tišler Zdeněk , Matějíčková Radka , Peroutková Kateřina , Hidalgo Herrador José Miguel
Published: January 2023

Waste rendering fat (WRF) is a solid residuum from rendering plants. WRF is inedible, even for animals, a mixture of lipids with a high content of (mono‐, di‐, tri‐) glycerol esters and free fatty acids. This study focuses on catalytic liquefaction and deoxygenation of WRF with four different iron‐based catalysts, namely, commercial Fe2O3 and three laboratory‐prepared alkali‐activated zeolite foams different in the iron precursor used for impregnation. Three various reaction times were tested. Laboratory‐prepared catalysts enabled a better yield of organic liquid than commercial ones. All catalysts had a positive efficiency of deoxygenation at all reaction times. The combination of Fe(II) and Fe(III) during the catalyst preparation had a beneficial effect.
Highly Selective Monomethylation of Amines with CO2/H2 via Ag/Al2O3 as a Catalyst
Authors: Long Yan , He Jie , Zhang Hang , Chen Yingkang , Liu Kang , Fu Junwei , Li Hongmei , Zhu Li , Lin Zhang , Stefancu Andrei , Cortes Emiliano , Zhu Mingshan , Liu Min
Published: January 2023

The selective synthesis of monomethylated amines with CO2 is particularly challenging because the formation of tertiary amines is thermodynamically more favorable. Herein, a new strategy for the controllable synthesis of N‐monomethylated amines from primary amines and CO2/H2 is explored. First‐principle calculations reveal that the dissociation of H2 via an heterolytic route reduces the reactivity of methylated amines and thus inhibit successive methylation. In situ DRIFTS proves the process of formation and decomposition of ammonium salt by secondary amine reversible binding with H+ on the Ag/Al2O3 catalyst, thereby reducing its reactivity. Meanwhile, the energy barrier for the rate‐determining step of monomethylation was much lower than that of overmethylation (0.34 eV vs. 0.58 eV) means amines monomethylation in preference to successive methylation. Under optimal reaction conditions, a variety of amines were converted to the corresponding monomethylated amines in good to excellent yields, and more than 90 % yield of product was obtained.