bluuebunny/crossref_metadata_2025 huggingface dataset:
The cosmic rate of pair-instability supernovae
Authors: Gabrielli Francesco , Lapi Andrea , Boco Lumen , Ugolini Cristiano , Costa Guglielmo , Sgalletta Cecilia , Shepherd Kendall , Di Carlo Ugo N , Bressan Alessandro , Limongi Marco , Spera Mario
Published: September 2024

Pair-instability supernovae (PISNe) have crucial implications for many astrophysical topics, including the search for very massive stars, the black hole mass spectrum, and galaxy chemical enrichment. To this end, we need to understand where PISNe are across cosmic time, and what are their favourable galactic environments. We present a new determination of the PISN rate as a function of redshift, obtained by combining up-to-date stellar evolution tracks from the parsec and franec codes, with an up-to-date semi-empirical determination of the star formation rate and metallicity evolution of star-forming galaxies throughout cosmic history. We find the PISN rate to exhibit a huge dependence on the model assumptions, including the criterion to identify stars unstable to pair production, and the upper limit of the stellar initial mass function. Remarkably, the interplay between the maximum metallicity at which stars explode as PISNe, and the dispersion of the galaxy metallicity distribution, dominates the uncertainties, causing a ∼ seven-orders-of-magnitude PISN rate range. Furthermore, we show a comparison with the core-collapse supernova rate, and study the properties of the favourable PISN host galaxies. According to our results, the main contribution to the PISN rate comes from metallicities between $\sim 10^{-3}$ and $10^{-2}$, against the common assumption that views very low metallicity, Population III stars as exclusive or dominant PISN progenitors. The strong dependencies we find offer the opportunity to constrain stellar and galaxy evolution models based on possible future (or the lack of) PISN observations.
Different regulation of stellar metallicities between star-forming and quiescent galaxies – insights into galaxy quenching
Authors: Baker William M , Maiolino Roberto , Bluck Asa F L , Belfiore Francesco , Curti Mirko , D’Eugenio Francesco , Piotrowska Joanna M , Tacchella Sandro , Trussler James A A
Published: September 2024

One of the most important questions in astrophysics is what causes galaxies to stop forming stars. Previous studies have shown a tight link between quiescence and black hole mass. Other studies have revealed that quiescence is also associated with ‘starvation’, the halting of gas inflows, which results in the remaining gas being used up by star formation and in rapid chemical enrichment. In this work, we find the missing link between these two findings. Using a large sample of galaxies, we uncover the intrinsic dependences of the stellar metallicity on galaxy properties. In the case of star-forming galaxies, stellar metallicity is primarily driven by stellar mass. However, for passive galaxies, the stellar metallicity is primarily driven by the stellar velocity dispersion. The latter is known to be tightly correlated with black hole mass. This result can be seen as connecting previous studies, where the integrated effect of black hole feedback (i.e. black hole mass, traced by the velocity dispersion) prevents gas inflows, starving the galaxy, which is seen by the rapid increase in the stellar metallicity, and leading to the galaxy becoming passive.
SPIRou monitoring of the protostar V347 Aur: binarity, magnetic fields, pulsed dynamo, and accretion
Authors: Donati J -F , Cristofari P I , Carmona A , Grankin K
Published: September 2024

We present in this paper an analysis of near-infrared observations of the 0.3-${\rm M}_{\odot }$ protostar V347 Aurigae (V347 Aur) collected with the SPIRou high-resolution spectropolarimeter and velocimeter at the 3.6-m Canada-France-Hawaii Telescope from 2019 October to 2023 April. From a set of 79 unpolarized and circularly polarized spectra of V347 Aur to which we applied Least-Squares Deconvolution (LSD), we derived radial velocities and longitudinal fields, along with their temporal variations over our monitoring campaign of 1258 d. Our data show that V347 Aur is an eccentric binary system with an orbital period of $154.6\pm 0.7$ d, experiencing strong-to-extreme accretion events near periastron. The companion is a $29.0\pm 1.6$${\rm M}_{{2\!\!_{\mathbf +}}}$ brown dwarf, a rare member of the brown dwarf desert of close companions around M dwarfs. We detect weak longitudinal fields ($\lt $100 G) at the surface of V347 Aur, significantly weaker than those of more evolved prototypical T Tauri stars. These fields show small-amplitude rotational modulation, indicating a mainly axisymmetric parent large-scale magnetic topology, and larger fluctuations at half the orbital period, suggesting that what we dub a ‘pulsed dynamo’ triggered by orbital motion and pulsed accretion operates in V347 Aur. Applying Zeeman–Doppler imaging to our circularly polarized LSD profiles, we find that the large-scale field of V347 Aur is mainly toroidal for most of our observations, with the toroidal component switching sign near periastron and apoastron. The weak large-scale dipole ($\simeq 30$ G) is not able to disrupt the disc beyond 1.3 $R_{\star }$ even at the lowest accretion rates, implying longitudinally distributed (rather than localized) accretion at the surface of the protostar.
HD 21520 b: a warm sub-Neptune transiting a bright G dwarf
Authors: Nies Molly , Mireles Ismael , Bouchy François , Dragomir Diana , Nicholson Belinda A , Eisner Nora L , Sousa Sergio G , Collins Karen A , Howell Steve B , Ziegler Carl , Hellier Coel , Addison Brett , Ballard Sarah , Bowler Brendan P , Briceño César , Clark Catherine A , Conti Dennis M , Dumusque Xavier , Edwards Billy , Gnilka Crystal L , Hobson Melissa , Horner Jonathan , Kane Stephen R , Kielkopf John , Lavie Baptiste , Law Nicholas , Lendl Monika , Littlefield Colin , Liu Huigen , Mann Andrew W , Mengel Matthew W , Oddo Dominic , Okumura Jack , Palle Enric , Plavchan Peter , Psaridi Angelica , Santos Nuno C , Schwarz Richard P , Shporer Avi , Wittenmyer Robert A , Wright Duncan J , Zhang Hui , Watanabe David , Medina Jennifer V , Villaseñor Joel , Ting Eric B , Christiansen Jessie L , Winn Joshua N , Stassun Keivan G , Seager S , Latham David W , Ricker George R
Published: September 2024

We report the discovery and validation of HD 21520 b, a transiting planet found with Transiting Exoplanet Survey Satellite and orbiting a bright G dwarf (V = 9.2, $T_{\rm eff} = 5871 \pm 62$ K, $R_{\star } = 1.04\pm 0.02\, {\rm R}_{\odot }$). HD 21520 b was originally alerted as a system (TOI-4320) consisting of two planet candidates with periods of 703.6 and 46.4 d. However, our analysis supports instead a single-planet system with an orbital period of $25.1292\pm 0.0001$ d and radius of $2.70 \pm 0.09\, {\rm R}_{{\oplus }}$. Three full transits in sectors 4, 30, and 31 match this period and have transit depths and durations in agreement with each other, as does a partial transit in sector 3. We also observe transits using CHEOPS and LCOGT. SOAR and Gemini high-resolution imaging do not indicate the presence of any nearby companions, and Minerva-Australis and CORALIE radial velocities rule out an on-target spectroscopic binary. Additionally, we use ESPRESSO radial velocities to obtain a tentative mass measurement of $7.9^{+3.2}_{-3.0}\, {\rm M}_{{\oplus }}$, with a 3$\sigma$ upper limit of 17.7 ${\rm M}_{{\oplus }}$. Due to the bright nature of its host and likely significant gas envelope of the planet, HD 21520b is a promising candidate for further mass measurements and for atmospheric characterization.
The circular velocity and halo mass functions of galaxies in the nearby Universe
Authors: Ristea Andrei , Cortese Luca , Groves Brent , Fraser-McKelvie A , Obreschkow Danail , Glazebrook Karl
Published: September 2024

The circular velocity function (CVF) of galaxies is a fundamental test of the Lambda cold dark matter ($\Lambda$CDM) paradigm as it traces the variation of galaxy number densities with circular velocity ($v_{\rm {circ}}$), a proxy for dynamical mass. Previous observational studies of the CVF have either been based on H i-rich galaxies, or encompassed low-number statistics and probed narrow ranges in $v_{\rm {circ}}$. We present a benchmark computation of the CVF between $100\,{\text{and}}\,350\ \rm {km\ s^{-1}}$ using a sample of 3527 nearby Universe galaxies, representative for stellar masses between $10^{9.2}\,{\text{and}}\,10^{11.9} \rm {{\rm M}_{\odot }}$. We find significantly larger number densities above 150 $\rm {km\ s^{-1}}$ compared to results from H i surveys, pertaining to the morphological diversity of our sample. Leveraging the fact that circular velocities are tracing the gravitational potential of haloes, we compute the halo mass function (HMF), covering $\sim$1 dex of previously unprobed halo masses ($10^{11.7}{\!-\!}10^{12.7} \rm {{\rm M}_{\odot }}$). The HMF for our sample, representative of the galaxy population with $M_{200}\geqslant 10^{11.35} \rm {{\rm M}_{\odot }}$, shows that spiral morphologies contribute 67 per cent of the matter density in the nearby Universe, while early types account for the rest. We combine our HMF data with literature measurements based on H i kinematics and group/cluster velocity dispersions. We constrain the functional form of the HMF between $10^{10.5}-10^{15.5} \rm {{\rm M}_{\odot }}$, finding a good agreement with $\Lambda$CDM predictions. The halo mass range probed encompasses 72$\substack{+5 -6}$ per cent ($\Omega _{\rm {M,10.5-15.5}} = 0.227 \pm 0.018$) of the matter density in the nearby Universe; 31$\substack{+5 -6}$ per cent is accounted for by haloes below $10^{12.7}\rm {{\rm M}_{\odot }}$ occupied by a single galaxy.
Insight into brain metallothioneins from bidirectional Zn2+ signaling in synaptic dynamics
Authors: Takeda Atsushi , Tamano Haruna
Published: September 2024

The basal levels as the labile Zn2+ pools in the extracellular and intracellular compartments are in the range of ∼10 nM and ∼100 pM, respectively. The influx of extracellular Zn2+ is used for memory via cognitive activity and is regulated for synaptic plasticity, a cellular mechanism of memory. When Zn2+ influx into neurons excessively occurs, however, it becomes a critical trigger for cognitive decline and neurodegeneration, resulting in acute and chronic pathogenesis. Aging, a biological process, generally accelerates vulnerability to neurodegenerative disorders such as Alzheimer's disease (AD) and Parkinson's disease (PD). The basal level of extracellular Zn2+ is age relatedly increased in the rat hippocampus, and the influx of extracellular Zn2+ contributes to accelerating vulnerability to the AD and PD pathogenesis in experimental animals with aging. Metallothioneins (MTs) are Zn2+-binding proteins for cellular Zn2+ homeostasis and involved in not only supplying functional Zn2+ required for cognitive activity, but also capturing excess (toxic) Zn2+ involved in cognitive decline and neurodegeneration. Therefore, it is estimated that regulation of MT synthesis is involved in both neuronal activity and neuroprotection. The present report provides recent knowledge regarding the protective/preventive potential of MT synthesis against not only normal aging but also the AD and PD pathogenesis in experimental animals, focused on MT function in bidirectional Zn2+ signaling in synaptic dynamics.
Unraveling bacterial adaptation strategies in the microbiome shaped by the chemical environment of the plant rhizosphere
Authors: Appidi Manasa R. , Bible Amber N. , Abraham Paul E. , Jawdy Sara S. , Hettich Robert L. , Morrell-Falvey Jennifer L.
Published: September 2024

The rhizosphere is a dynamic environment where rhizodeposits that include primary and secondary metabolites and mucilage serve as nutrient sources for soil microorganisms, attracting them towards plant roots. However, understanding how these microbes specifically respond to plant root chemical signals has been hindered by the challenges of disentangling physical and chemical interactions between the microbes and plant roots. To address this, we implemented an innovative filter-based experimental setup on plant roots that creates a physical barrier while facilitating the exchange of chemical signals. The proteomic analysis of ten Populus root-associated bacterial strains grown in the presence or absence of a plant in either individual or mixed community conditions provided detailed insights into the functional responses of these strains to the root chemical environment. Additionally, this approach allowed us to discern the impact of root exudates on overall community dynamics. In particular, metaproteomic analyses revealed that each of these ten microbial members respond uniquely to the presence of the plant, with Bacillus and Pantoea exhibiting the most dramatic favorable impact. Proteomic examination revealed the details of metabolism fine-tuning, including processes such as chemotaxis and ABC transporter proteins. This study demonstrates the application of a filter-based experimental set up to study microbial responses to plant chemicals and sheds light on adaptation strategies employed by various bacterial strains for survival in the rhizosphere.
Innovative (and Safe) Techniques With Supraglottic Airways
Authors: Herrera Katherine , Tufail Bilal , Osborn Irene
Published: September 2024

Supraglottic airways have been utilized as an alternative to facemask ventilation and endotracheal intubation and thus have been essential to airway management since their introduction in the late 1980s. This chapter describes basic considerations in their use and an update on current clinical practice, with an emphasis on safe management. The devices have evolved to meet today's clinical airway challenges, and they provide benefits for patients and practitioners.
Pedicle Screw Placement with Augmented Reality Versus Robotic-Assisted Surgery
Authors: Altorfer Franziska C.S. , Kelly Michael J. , Avrumova Fedan , Burkhard Marco D. , Zhu Jiaqi , Abel Frederik , Cammisa Frank P. , Sama Andrew , Farshad Mazda , Lebl Darren R.
Published: September 2024

Study Design.

This was a single-center prospective clinical and radiographic analysis of pedicle screw instrumentation with Robotic-assisted navigation (RAN) and augmented reality (AR).

Objective.

This study aimed to compare the accuracy of lumbosacral pedicle screw placement with RAN versus AR.

Summary of Background Data.

RAN and AR have demonstrated superior accuracy in lumbar pedicle screw placement compared to conventional free-hand techniques. RAN and AR techniques both tout specific advantages over their counterparts, but to date, no study has directly compared the two technologies regarding pedicle screw accuracy.

Patients and Methods.

Patients who underwent RAN or head-mounted AR navigated lumbosacral (L1–S1) pedicle screw placement for degenerative conditions were included. Screw accuracy was assessed by two independent reviewers on intraoperative 3D fluoroscopic scans using the Gertzbein and Robbins scale. A generalized linear mixed model was applied to evaluate the relationship between the screw placement technique and accuracy.

Results.

212 patients undergoing lumbosacral instrumentation with a total of 1,211 pedicle screws placed using RAN (n=108; screws= 827) or AR (n=104; screws= 384). Overall, Grade A was achieved in 92.6% of screws. No significant difference was found between RAN and AR screw placement regarding the incidence of accurate (Grade-A and -B screws; RAN n=824; 99.6% and AR n=379, 98.7%) versus inaccurate screws (Grade-C and -D screws; RAN n=3, 0.4% and AR n=5, 1.3%). When comparing “optimal” Grade-A screws (RAN n= 787, 95.2%, AR n=345, 89.8%) versus all other screws (B, C, and D), significantly higher accuracy was achieved using RAN (P=0.001).

Conclusion.

RAN and AR both achieved high accuracy in lumbosacral pedicle screw placement, proving reliable for this procedure. However, RAN resulted in significantly more Grade-A screw placements than AR.
Mitochondrial genetic variations in leukemia: a comprehensive overview
Authors: Zhang Ao , Liu Wenbing , Qiu Shaowei
Published: September 2024

Leukemias are a group of heterogeneous hematological malignancies driven by diverse genetic variations, and the advent of genomic sequencing technologies facilitates the investigation of genetic abnormalities in leukemia. However, these sequencing-based studies mainly focus on nuclear DNAs. Increasing evidence indicates that mitochondrial dysfunction is an important mechanism of leukemia pathogenesis, which is closely related to the mitochondrial genome variations. Here, we provide an overview of current research progress concerning mitochondrial genetic variations in leukemia, encompassing gene mutations and copy number variations. We also summarize currently accessible mitochondrial DNA (mtDNA) sequencing methods. Notably, somatic mtDNA mutations may serve as natural genetic barcodes for lineage tracing and longitudinal assessment of clonal dynamics. Collectively, these findings enhance our understanding of leukemia pathogenesis and foster the identification of novel therapeutic targets and interventions.
Association of Supranormal Left Ventricular Function With Major Adverse Cardiovascular Events: A Systematic Review of Literature
Authors: Rahim Abdul , Riaz Gondal Muhammad Umer , Ali Farman , Ullah Asif , Burki Atta ul Haq , Kumar Danesh , Vishal Hari , Iqbal Arham , Malik Jahanzeb
Published: September 2024

This systematic review aims to assess the prognostic implications of supranormal left ventricular ejection fraction (snLVEF) in cardiovascular disease, particularly heart failure (HF), and explore its association with major adverse cardiovascular events (MACE). A comprehensive search of electronic databases was conducted to identify relevant studies examining the relationship between snLVEF and cardiovascular outcomes. Studies utilizing various imaging modalities, including echocardiography, cardiac positron emission tomography, computed tomography, and cardiac magnetic resonance imaging, were included. Data extraction and quality assessment were performed according to predefined criteria. The review identified several studies investigating the association between snLVEF and cardiovascular outcomes. Findings revealed an increased risk of MACE, including HF hospitalization and stroke, in patients with snLVEF, particularly in women. Coronary microvascular dysfunction and autonomic dysregulation were proposed mechanisms underlying these associations. However, conflicting results were observed when focusing exclusively on snLVEF, with some studies reporting similar outcomes between snLVEF and other HF subgroups. snLVEF (>65%) appears to be associated with an elevated risk of MACE, particularly in women, suggesting a U-shaped mortality curve. However, the prognostic implications may vary among HF patients, necessitating further research to elucidate the specific contributions of HF phenotypes and comorbidities. These findings underscore the importance of tailored risk assessment and management strategies for patients with snLVEF, particularly in the context of HF.
Dose Estimation Utility in a Population Pharmacokinetic Analysis of Inhaled Δ9-Tetrahydrocannabinol Cannabis Market Products in Occasional and Daily Users
Authors: Henthorn Thomas K. , Wang George S. , Dooley Greg , Brooks-Russell Ashley , Wrobel Julia , Limbacher Sarah , Kosnett Michael
Published: September 2024

Background:

Unusually high variability in blood Δ9-tetrahydrocannabinol (THC) concentrations have been observed in subjects inhaling similar cannabis products over similar time periods when consumption is ad libitum. This makes simple gravimetric dose estimation a poor predictor of THC exposure. Population pharmacokinetic analyses of blood THC concentration versus time data are routinely used to estimate pharmacokinetic parameters. The aim of this study was to estimate the inhaled dose of THC in occasional and daily users of high potency market cannabis.

Methods:

Blood THC concentrations were measured for 135 minutes from 29 participants who either smoked high concentration flower or inhaled concentrates ad libitum during a 15-minute session. Frequent blood samples were obtained over the following 135 minutes.

Results:

The estimated central and rapidly equilibrating volumes of distribution of a 3-compartment model were 19.9 ± 1.2 and 51.6 ± 4.7 L whereas the intercompartmental clearances were 1.65 ± 0.14 and 1.75 ± 0.10 L/min, respectively. Covariate-adjusted analysis revealed that the estimated inhaled THC dose was considerably less among occasional users compared with daily users.

Conclusions:

Three-compartment pharmacokinetics of THC did not differ among the 3 user groups, and the early phase (first 135 minutes postinception of inhalation) kinetics were similar to those previously described after smoking low potency cannabis products. Therefore, inhaled THC dose can be estimated from pharmacokinetic data and covariate-driven adjustments can be used to estimate THC doses, based on the participant cannabis usage pattern (occasional versus daily), improving the accuracy of THC exposure estimates compared with those derived from weighed THC content alone.
Macrophage metabolism impacts metabolic dysfunction-associated steatotic liver disease and its progression
Authors: Yang Ming , Liu Shuai , Sui Yuxiang , Zhang Chunye
Published: September 2024

Metabolic dysfunction-associated steatotic liver disease (MASLD), with a progressive form of metabolic dysfunction-associated steatohepatitis (MASH), is the leading chronic liver disease worldwide, which can progress to advanced liver disease and hepatocellular carcinoma. MASLD is tightly associated with metabolic disorders such as obesity, insulin resistance, and type 2 diabetes. Macrophages, as an innate immune component and a linker of adaptive immune response, play important roles in the pathogenesis and treatment of MASLD or MASH. Metabolic reprogramming can regulate macrophage activation and polarization to inhibit MASLD or MASH progression to advanced liver disease. Here, we summarize the underlying mechanisms of how different metabolites such as amino acids, glucose, and fatty acids can regulate macrophage function and phenotype, the factors that regulate macrophage metabolism, and potential treatment options to regulate macrophage function in MASLD or MASH, as well as other associated metabolic disorders.
“Craniometric and Volumetric Analyses of Normocephalic and Scaphocephalic Patients with Nonsyndromic Single-Suture Sagittal Craniosynostosis”
Authors: Velazquez Alexander , Lebhar Michael S. , Yang Johnny , McCandless Martin , Pitre David , Shiflett Mason , Weaver Kristen , Nichols Todd , Hoppe Ian C. , Humphries Laura S.
Published: September 2024

Purpose:

Non-syndromic single-suture sagittal craniosynostosis presentation spans scaphocephalic and normocephalic head shapes. Herein, we studied craniometric differences between scaphocephalic and normocephalic patients with sagittal synostosis.

Methods:

Head CT scans of 20 scaphocephalic and 20 normocephalic sagittal synostosis patients and their age- and sex-matched controls were analyzed, including cranial base angles, distances-from-midline, and intracranial volumes.

Results:

Cranial index was significantly decreased in index groups compared to controls (p<0.001, respectively). Right external acoustic meatus angle (EAMA) was significantly larger in scaphocephalic (p<0.001) and left EAMA was significantly smaller in normocephalic patients (p=0.002) when compared with controls. Midline angular analysis showed that bifrontal angle was significantly smaller amongst scaphocephalic patients versus controls (p=0.026). Cranial base distances-from-midline were longer to the right and left internal acoustic meatus and shorter to the euryon-to-zygomaticofrontal suture for both groups of cases than their controls (p<0.05). Scaphocephalic patients had a larger anterior cranial volume ratio (18% vs 13%, p<0.001) and normocephalic patients had a larger posterior volume ratio (42% vs 33%, p<0.001) than controls. Scaphocephalic patients had larger anterior volume ratios than normocephalic patients (1.66 vs 1.16, p=0.025, but smaller posterior compartment volume ratios (0.90 vs 1.53, p<0.001).

Conclusion:

There are rightward asymmetries of the linear and angle cranial base measurements in both index groups. Intracranial volume distribution lies anteriorly in scaphocephalic patients but posteriorly in normocephalic patients. These data show craniometric evidence that although normocephalic and scaphocephalic patients share the diagnosis of “sagittal synostosis,” they are morphometrically different than each other and controls.
Kondoa tianchiensis f.a., sp. nov., an anamorphic yeast species isolated from plant leaves
Authors: Cai Dan-Yang , Liu Shan , Hui Feng-Li
Published: September 2024

Two yeast strains, NYNU 236122 and NYNU 236180, were isolated from plant leaves collected in Tianchi Mountain, Henan Province, central China. Molecular phylogenetic analyses revealed the closest relatives of the strains are three described Kondoa species, Kondoa chamaenerii, Kondoa miscanthi, and Kondoa subrosea. Genetically, the isolated strains differed from the type strains of their three related species by 2–11(0.2–1.8%) base substitutions in the D1/D2 domain, 16–40 (2.6–5.6%) base mismatches in the internal transcribed spacer region, and more than 10.1% base substitutions in the partial RPB2 gene. Furthermore, the two strains differ physiologically from their closest related species, K. chamaenerii, in their ability to assimilate dl-lactate, nitrite, and l-lysine and their inability to assimilate nitrate. Additionally, they differ from K. miscanthi and K. subrosea in their ability to assimilate inulin, d-gluconate, and l-lysine. The species name of Kondoa tianchiensis f.a., sp. nov. is proposed with holotype CICC 33616T (Mycobank MB 853544).
Queuosine salvage in Bartonella henselae Houston 1: a unique evolutionary path
Authors: Quaiyum Samia , Yuan Yifeng , Sun Guangxin , Ratnayake R. M. Madhushi N. , Hutinet Geoffrey , Dedon Peter C. , Minnick Michael F. , de Crécy-Lagard Valérie
Published: September 2024

Graphical Abstract

The substrate specificity of bacterial TGT and Q precursor transporter protein shifts from preQ1 to the queuine base in intracellular human pathogens such as Chlamydia trachomatis, driven by adaptation to the intracellular environment. The facultative intracellular pathogen Bartonella henselae exhibits a rare dual-substrate specificity for these Q salvage enzymes that represents an evolutionary transition state.
Integrator complex subunit 12 knockout overcomes a transcriptional block to HIV latency reversal
Authors: Gray Carley N. , Ashokkumar Manickam , Janssens Derek H. , Kirchherr Jennifer , Allard Brigitte , Hsieh Emily , Hafer Terry L. , Archin Nancie M. , Browne Edward P. , Emerman Michael
Published: September 2024

The latent HIV reservoir is a major barrier to HIV cure. Combining latency reversal agents (LRAs) with differing mechanisms of action such as AZD5582, a non-canonical NF-kB activator, and I-BET151, a bromodomain inhibitor is appealing towards inducing HIV-1 reactivation. However, even this LRA combination needs improvement as it is inefficient at activating proviruses in cells from people living with HIV (PLWH). We performed a CRISPR screen in conjunction with AZD5582 & I-BET151 and identified a member of the Integrator complex as a target to improve this LRA combination, specifically Integrator complex subunit 12 (INTS12). Integrator functions as a genome-wide attenuator of transcription that acts on elongation through its RNA cleavage and phosphatase modules. Knockout of INTS12 improved latency reactivation at the transcriptional level and is more specific to the HIV-1 provirus than AZD5582 & I-BET151 treatment alone. We found that INTS12 is present on chromatin at the promoter of HIV and therefore its effect on HIV may be direct. Additionally, we observed more RNAPII in the gene body of HIV only with the combination of INTS12 knockout with AZD5582 & I-BET151, indicating that INTS12 induces a transcriptional elongation block to viral reactivation. Moreover, knockout of INTS12 increased HIV-1 reactivation in CD4 T cells from virally suppressed PLWHex vivo, and we detected viral RNA in the supernatant from CD4 T cells of all three virally suppressed PLWH tested upon INTS12 knockout suggesting that INTS12 prevents full-length HIV RNA production in primary T cells. Finally, we found that INTS12 more generally limits the efficacy of a variety of LRAs with different mechanisms of action.
A Bayesian framework for inferring dynamic intercellular interactions from time-series single-cell data
Authors: Park Cameron , Mani Shouvik , Beltran-Velez Nicolas , Maurer Katie , Huang Teddy , Li Shuqiang , Gohil Satyen , Livak Kenneth J. , Knowles David A. , Wu Catherine J. , Azizi Elham
Published: September 2024

Characterizing cell–cell communication and tracking its variability over time are crucial for understanding the coordination of biological processes mediating normal development, disease progression, and responses to perturbations such as therapies. Existing tools fail to capture time-dependent intercellular interactions and primarily rely on databases compiled from limited contexts. We introduce DIISCO, a Bayesian framework designed to characterize the temporal dynamics of cellular interactions using single-cell RNA-sequencing data from multiple time points. Our method utilizes structured Gaussian process regression to unveil time-resolved interactions among diverse cell types according to their coevolution and incorporates prior knowledge of receptor–ligand complexes. We show the interpretability of DIISCO in simulated data and new data collected from T cells cocultured with lymphoma cells, demonstrating its potential to uncover dynamic cell–cell cross talk.
Bootstrap of the defect
1/2
BPS Wilson lines in
N=4
Chern-Simons-matter theories
Authors: Pozzi Riccardo Giordana , Trancanelli Diego
Published: September 2024

We compute correlation functions of local operator insertions on the 1/2 Bogomol’nyi-Prasad-Sommerfield Wilson lines of N=4 Chern-Simons-matter theories in three dimensions. We study the algebra preserved by the defect conformal field theory supported on the line, identify the superdisplacement multiplet, and discuss some of its weak-coupling realizations. By employing a superspace description, we present the four-point functions of the superdisplacement and show how they are determined by functions of cross ratios. Within an analytic bootstrap approach, we derive these functions at leading and next-to-leading order at strong coupling, obtaining a result in agreement with appropriate orbifolds of the ABJM case considered in Bianchi [Analytic bootstrap and Witten diagrams for the ABJM Wilson line as defect CFT1, ].

Published by the American Physical Society
2024
Low-dose electron microscopy imaging for beam-sensitive metal–organic frameworks
Authors: Liang Yuhang , Zhou Yi
Published: September 2024

Metal–organic frameworks (MOFs) have garnered significant attention in recent years owing to their exceptional properties. Understanding the intricate relationship between the structure of a material and its properties is crucial for guiding the synthesis and application of these materials. (Scanning) Transmission electron microscopy (S)TEM imaging stands out as a powerful tool for structural characterization at the nanoscale, capable of detailing both periodic and aperiodic local structures. However, the high electron-beam sensitivity of MOFs presents substantial challenges in their structural characterization using (S)TEM. This paper summarizes the latest advancements in low-dose high-resolution (S)TEM imaging technology and its application in MOF material characterization. It covers aspects such as framework structure, defects, and surface and interface analysis, along with the distribution of guest molecules within MOFs. This review also discusses emerging technologies like electron ptychography and outlines several prospective research directions in this field.
Tracing the evolution of a parallel-engaged architectural pedagogy of care in South Africa
Authors: Felix Sandra Lourenço
Published: September 2024

Purpose

Tracing the development of a parallel-engaged pedagogy of care that extended and adapted the critical and transformative pedagogies of Freire, De Sousa Santos and hooks to the South African context. The development of this transformative pedagogy addresses the local conditions of an architectural design studio at a postcolonial, post-Apartheid and post “Fees must Fall” protests South African university. This pedagogy used practice-based design research to build a more conscious, critical and careful design practice in both students and educators.

Design/methodology/approach

The pedagogy was developed through participatory action research, over five years, from 2019 to 2023 including two years of the COVID-19 pandemic. Parallel and active engagement of students and educators within a nurturing and caring environment evolved from year to year, through a conscious and critical reflection on the process. Student surveys, reflective essays and focus groups unearth the impact of the parallel-engaged pedagogy of care.

Findings

The parallel-engaged pedagogy of care was shown to support and scaffold students becoming more conscious, critical and careful in their design practices validating diverse lived experiences as generative for design and important for social justice and transformative equity.

Research limitations/implications

The parallel-engaged pedagogy of care is part of a global shift to more transformative pedagogies that address student diversity and decoloniality.

Originality/value

Through dismantling traditional hierarchical teaching modes, the pedagogy is more student-led, agile and adaptable. Through centring and demonstrating care in the pedagogy, students are encouraged to develop both self-care and care in their design practice. This is especially critical in the South African context where the cultural capital of the institution, with its roots in colonial and Apartheid education differs from that of the majority of students of colour.
Is it really natural? How minimalist food packaging influences consumers’ perception of product naturalness
Authors: Saintives Camille , Meral Hélène
Published: September 2024

Purpose

Although prior research has shown the influence of the degree of simplicity (versus complexity) in packaging design on consumer’s product and brand perceptions, no research to date has analyzed the effect of minimalist packaging on perceived product naturalness. This research thus aims to investigate the underlying mechanisms explaining how a minimalist food packaging design may lead consumers to perceive a product as more natural.

Design/methodology/approach

The paper is based on two pre-tests and two experiments (N = 152 and N = 220) focusing on food products. Serial–parallel mediations are performed to test the effect of minimalist packaging design on perceived product naturalness.

Findings

In a food consumption context, we demonstrate and replicate the positive impact of minimalism on perceived product uniqueness, which then positively influences both production mode and perceived taste, which, in turn, increases perceived product naturalness.

Originality/value

The findings provide new insights into the influence of food packaging design on consumers’ product perception. This paper offers a deeper understanding of the relationship between minimalist food packaging design and product naturalness by highlighting the mediating roles of perceived uniqueness, production mode and perceived taste.
Impact of green self-managed teams on firm’s performance: a moderating serial mediation model from an emerging market
Authors: Kundu Subhash C. , Chahar Purnima
Published: September 2024

Purpose

Based on the Social Exchange Theory (SET), the paper attempts to extend the research on the relationship between green self-managed teams and firm performance by exploring the serial mediation of extra-role green behavior and environmental performance. Furthermore, via moderated mediation, the study inspected the differences in relationships among these variables for manufacturing and service organizations.

Design/methodology/approach

Data of 407 respondents from 122 manufacturing and service organizations (having green self-managed teams) operating in India were collected using purposive sampling. Various statistical techniques like confirmatory factor analysis (CFA), correlations, multiple regressions and bootstrapping were employed.

Findings

The results indicated that extra-role green behavior and environmental performance served as serial mediators. Additionally, the nature of the organizations significantly moderated several indirect relationships, with one pathway found to be insignificant.

Research limitations/implications

The study may be limited by the fact that the data were collected at a single moment in time rather than using a longitudinal design.

Practical implications

The study guides service organizations to attract environmentally conscious employees by promoting green self-managed teams and manufacturing organizations to enrich their operations and service delivery through such teams.

Originality/value

The study uniquely examines how green self-managed teams addressing environmental issues contribute to improved firm performance through mutual exchanges. It also advances existing literature by conducting a comparative analysis across manufacturing and service organizations in an emerging Indian market.
The performance monitoring system for a hydrostatic turntable: an improved intelligent algorithm based on the IPSO-NN model
Authors: Zhao Yongsheng , Luo Jiaqing , Li Ying , Zhang Caixia , Ma Honglie
Published: September 2024

Purpose

The combination of improved PSO (IPSO) algorithm and artificial neural network (ANN) model for intelligent monitoring of the bearing performance of the hydrostatic turntable.

Design/methodology/approach

This paper proposes an artificial neural network model based on IPSO algorithm for intelligent monitoring of hydrostatic turntables.

Findings

The theoretical model proposed in this paper improves the accuracy of the working performance of the static pressure turntable and provides a new direction for intelligent monitoring of the static pressure turntable. Therefore, the theoretical research in this paper is novel.

Originality/value

Theoretical novelties: an ANN model based on the IPSO algorithm is designed to monitor the load-bearing performance of a static pressure turntable intelligently; this study show that the convergence accuracy and convergence speed of the IPSO-NN model have been improved by 52.55% and 10%, respectively, compared to traditional training models; and the proposed model could be used to solve the multidimensional nonlinear problem in the intelligent monitoring of hydrostatic turntables.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-03-2024-0081/
Competitiveness of the South African citrus fruit industry in the global market and its macroeconomic determinants
Authors: Seleka Tebogo Bruce , Obi Ajuruchukwu , Motsatsi Johane Moilwa
Published: September 2024

Purpose

To assess South Africa’s (SA’s) citrus export competitiveness in the global market and identify its macroeconomic drivers.

Design/methodology/approach

The Normalized Revealed Comparative Advantage (NRCA) index is employed to measure export competitiveness. An ARDL-EC model is then estimated to identify the macroeconomic determinants of SA’s citrus export competitiveness.

Findings

SA’s citrus export competitiveness declined before the mid-1990s and rose thereafter. On balance, the country improved from the fourth to the second most competitive citrus exporter. A long-run relationship was established between the NRCA scores and the real exchange rate and real GDP per capita growth rate. The export price exerted a positive short-run influence on citrus export competitiveness. The rise in SA’s citrus export competitiveness since the mid-1990s was mainly driven by the rising citrus export price and real exchange rate depreciation.

Research limitations/implications

Future research could explore the determinants of SA’s export competitiveness using panel gravity models of bilateral trade flows to isolate the impact of macroeconomic variables and trade restricting/enhancing policies of importing countries.

Originality/value

The article employs the NRCA index, which can measure comparative advantage across space and over time. It is the first to econometrically estimate the macroeconomic determinants of citrus export competitiveness in SA. Application of the ARDL-EC framework yields both short- and long-run effects of macroeconomic variables on export competitiveness.
Blockchain implementation for food safety in supply chain: A review
Authors: Sri Vigna Hema V. , Manickavasagan Annamalai
Published: September 2024

Food safety has emerged as the topmost priority in the current fast‐paced food industry era. According to the World Health Organization, around 600 million people, approximately 1 in 10 individuals worldwide, experience illness due to contaminated food consumption, resulting in nearly 0.42 million fatalities annually. The recent development in software and hardware sectors has created opportunities to improve the safety concerns in the food supply chain. The objective of this review is to explain the fundamentals of blockchain and its integration into the supply chain of various food commodities to enhance food safety. This paper presents the analysis of 31 conceptual works, 10 implementation works, 39 case studies, and other investigations in blockchain‐based food supply chain from a total of 80 published papers. In this paper, the significance of adapting conceptual ideas into practical applications for effectively tracing food commodities throughout the supply chain has been discussed. This paper also describes the transformative role of blockchain platforms in the food industry, providing a decentralized and transparent ledger to access real‐time and immutable records of a product's journey. In addition, both the positive impacts and challenges associated with implementing blockchain technology in the food supply chain have been evaluated. In summary, the blockchain‐based food supply chains offer greater transparency, traceability, and trust, ultimately resulting in higher standards of food safety and quality.
Competing ambitions regarding the global governance of artificial intelligence: China, the US, and the EU
Authors: Mokry Sabine , Gurol Julia
Published: September 2024

As artificial intelligence (AI) technologies are developed and used across borders and have the potential to transform societies worldwide, global regulation thereof becomes necessary. However, key differences exist in how the leading players in the field, China, the United States, and the EU, view these technologies and approach their regulation. This article traces their respective ambitions on the global governance of AI technologies. It asks how the three each envision the latter as well as their role therein. Drawing on frame analysis, we find that while concrete ideas for coordinating regulation attempts seem to be of secondary importance, all three actors feel the need to position themselves within the new race for leadership on AI regulation. This results in a flurry of suggested proposals on how AI should be regulated internationally. Only recently have the actors started to reflect on why global regulation is necessary and to highlight the respective benefits of their proposal. Amidst current geopolitical tensions, the global regulation of AI has become an instrument of global power ambitions. Such competition bears huge risks for the further fragmentation of the global institutional architecture as well as for deepening tensions between China, the US, and the EU.
Vaginoscopy to investigate vaginal bleeding and discharge in prepubertal girls
Authors: Short Asha , Sit Andrea , Gerstl Brigitte , Mallinder Hayley , Deans Rebecca
Published: September 2024

Study Objective

To investigate the aetiology of vaginal bleeding and discharge in prepubescent girls, and the utility of vaginoscopy for making a diagnosis.

Design

Retrospective observational study over 14 years.

Setting

Two major tertiary referral paediatric hospitals in Sydney, Australia.

Participants

All prepubescent girls (n = 104) who presented with vaginal bleeding and/or discharge and subsequently underwent a vaginoscopy. A total of 120 procedures were performed.

Main Outcome Measures

Surgical findings at vaginoscopy; number needed to investigate (NNI) to establish a diagnosis and to exclude malignancy.

Results

There were 52/120 (43.3%) vaginoscopies which provided a positive diagnosis, including 36/86 (41.8%) performed for bleeding and 16/34 (47.0%) for vaginal discharge. In the vaginal bleeding group, the causes found were a foreign body in 11/86 (12.7%), vulvovaginitis in 6/86 (6.9%), benign Mullerian papilloma in 5/86 (5.8%), trauma in 4/86 (4.6%), and malignant tumours in 2/86 (2.3%). To establish a diagnosis in girls presenting with vaginal bleeding, the NNI was 2.4; to detect a malignancy the NNI was 43.0. In girls presenting with vaginal discharge, vulvovaginitis was noted intraoperatively in 7/34 (20.6%) and a foreign body was found in 7/34 (20.6%). No malignant tumours were identified in the vaginal discharge group. To establish a diagnosis in girls presenting with vaginal discharge, the NNI was 2.1.

Conclusions

Vaginoscopy is an important diagnostic tool in the setting of vaginal bleeding in prepubescent girls, allowing the ability to confirm a diagnosis, and importantly, to exclude malignancy.
Pharmacokinetics of vancomycin in sputum of intubated patients: Optimized intravenous delivery vs. inhaled therapy
Authors: Palmer Lucy B. , Monteforte Melinda , Smaldone Gerald C.
Published: September 2024

Aims

Intubated patients with methicillin‐resistant Staphylococcus aureus pneumonia, fail optimized treatment with intravenous (IV) vancomycin (serum trough 15–20 μg/mL) in 38–79% of cases. Airway blood flow is diminished compared to alveoli and we hypothesized that vancomycin concentrations achieved in airway secretions are suboptimal and nonbactericidal. Targeted therapy by inhalation may overcome this deficit.

Methods

Airway pharmacokinetics of optimized IV and inhaled vancomycin in infected clinically stable prolonged mechanically ventilated patients were measured. First, IV vancomycin was given until optimized concentrations were achieved (15–20 μg/mL), and, at the same time point, sputum vancomycin concentrations were measured. Then, sputum concentrations were re‐assessed after 4 treatments of inhaled vancomycin (120 mg/2 mL) via a previously characterized nebulizing system that deposited 18 ± 2 mg in the lungs. Vancomycin post‐distribution phase serum peak and trough concentrations were also obtained. Serum albumin was measured to assess binding to vancomycin.

Results

Mean serum trough concentration was 18.4 ± 6.5 μg/mL. Sputum concentrations were affected by serum albumin. Only patients with severe hypoalbuminaemia had penetration of drug leading to therapeutic (15.7–17 μg/mL) sputum concentrations. Following inhaled vancomycin, sputum concentrations increased significantly to 199 ± 37.0 μg/mL (P = .002) exceeding minimum inhibitory concentration by 2 orders of magnitude.

Conclusion

Despite optimized serum concentrations, patients with albumin near normal had suboptimal concentrations of vancomycin in their sputum. Inhaled therapy may be clinically important for successful treatment of ventilator‐associated methicillin‐resistant Staphylococcus aureus infection. Further studies of inhaled therapy are needed to define their role as adjunctive therapy in ventilator‐associated pneumonia and as single therapy in tracheobronchitis.