bluuebunny/crossref_metadata_2025 huggingface dataset:
Hyperactive Ras disrupts cell size control and a key step in cell cycle entry in budding yeast
Authors: DeWitt Jerry T , Chinwuba Jennifer C , Kellogg Douglas R
Published: August 2023

Severe defects in cell size are a nearly universal feature of cancer cells. However, the underlying causes are unknown. A previous study suggested that a hyperactive mutant of yeast Ras (ras2G19V) that is analogous to the human Ras oncogene causes cell size defects, which could provide clues to how oncogenes influence cell size. However, the mechanisms by which ras2G19V influences cell size are unknown. Here, we found that ras2G19V inhibits a critical step in cell cycle entry, in which an early G1 phase cyclin induces transcription of late G1 phase cyclins. Thus, ras2G19V drives overexpression of the early G1 phase cyclin Cln3, yet Cln3 fails to induce normal transcription of late G1 phase cyclins, leading to delayed cell cycle entry and increased cell size. ras2G19V influences transcription of late G1 phase cyclins via a poorly understood step in which Cln3 inactivates the Whi5 transcriptional repressor. Previous studies found that yeast Ras relays signals via protein kinase A (PKA); however, ras2G19V appears to influence late G1 phase cyclin expression via novel PKA-independent signaling mechanisms. Together, the data define new mechanisms by which hyperactive Ras influences cell cycle entry and cell size in yeast. Hyperactive Ras also influences expression of G1 phase cyclins in mammalian cells, but the mechanisms remain unclear. Further analysis of Ras signaling in yeast could lead to discovery of new mechanisms by which Ras family members control expression of G1 phase cyclins.
Unclean Cooking Fuel Use and Health Outcomes in Older Adults: Potential Mechanisms, Public Health Implications, and Future Directions
Authors: Smith Lee , López Sánchez Guillermo F , Soysal Pinar , Tully Mark A , Koyanagi Ai
Published: August 2023

Background

Unclean cooking fuels (ie, polluting fuels including kerosene/paraffin, and solid fuels) are a major contributor to diseases and mortality, specifically in low- and middle-income countries.

Methods

This review aimed to identify potential mechanisms, public health implications, and future directions of unclean cooking fuel use and health outcomes in older adults.

Results

There is an expanding body of literature to demonstrate associations between unclean cooking fuel use and multiple mental and physical health outcomes in older adults. Two key mechanisms likely driving such associations include inflammation and oxidative stress.

Conclusions

Considering that inflammation and oxidative stress have been implicated in multiple other health conditions (eg, arthritis and osteoporosis) in addition to those investigated to date on this topic it would be prudent to continue investigation of unclean cooking fuel use and with yet to be studied health outcomes. Moreover, future research is indeed now required to identify pathways to eliminating unclean cooking fuel globally to better the health of an aging global population and to support the implementation of Sustainable Development Goal 7.
Single-Cell Mapping of Large and Small Arteries During Hypertensive Aging
Authors: Cheng Jun , Wu Hong , Xie Cheng , He Yangyan , Mou Rong , Zhang Hongkun , Yang Yan , Xu Qingbo
Published: August 2023

Vascular aging is directly related to several major diseases including clinical primary hypertension. Conversely, elevated blood pressure itself accelerates vascular senescence. However, the interaction between vascular aging and hypertension has not been characterized during hypertensive aging. To depict the interconnectedness of complex mechanisms between hypertension and aging, we performed single-cell RNA sequencing of aorta, femoral and mesentery arteries, respectively, from male Wistar Kyoto rats and male spontaneously hypertensive rats aging 16 or 72 weeks. We integrated 12 data sets to map the blood vessels of senile hypertension from 3 perspective: vascular aging, hypertension, and vascular type. We found that aging and hypertension independently exerted a significant impact on the alteration of cellular composition and artery remodeling, even greater when superimposed. Consistently, smooth muscle cells (SMCs) underwent phenotypic switching from contractile toward synthetic, apoptotic, and senescent SMCs with aging/hypertension. Furthermore, we identified 3 subclusters of Spp1high, encoding protein osteopontin (OPN), synthetic SMCs, Spp1high matrix activated fibroblasts, and Spp1high scar-associated macrophage involved in hypertensive aging. Spp1high scar-associated macrophage enriched for reactive oxygen species metabolic process and cell migration-associated function. Cell–cell communication analysis revealed Spp1-Cd44 receptor pairing was markedly aggravated in the hypertensive aging condition. Importantly, the concentration of serum OPN significantly potentiated in aged hypertensive patients compared with the normal group. Thus, we provide a comprehensive cell atlas to systematically resolve the cellular diversity and dynamic cellular communication changes of the vessel wall during hypertensive aging, identifying a protein marker OPN as a potential regulator of vascular remodeling during hypertensive aging.
Spatial and network mapping of comorbidity with trachoma and visual-impairing NCDs in a pastoralist community in Kenya: implications for SDGs and UHC
Authors: Chweya R N , Onyango C A , Saigilu S , Mwangi C , Gachohi J M
Published: August 2023

Background

We explore the spatial distribution of comorbidity with trachoma and potentially visual-impairing non-communicable diseases (NCDs) and their risk factors among Kenyan pastoralists.

Methods

Using a cross-sectional study design, we recruited and clinically examined 262 study participants for NCDs (hypertension or diabetes) and trachoma using the World Health Organization grading system. Network models estimated interactions and risks linked with trachoma and NCDs while the Poisson point process determined their spatial distribution.

Results

Of the 262 participants, 140 (53%) had trachoma, with >71% of these cases identified among females and those >60 y of age. A total of 36 trachoma cases co-occurred with hypertension (26%) and diabetes (0.01%). NCDs were frequent among those with recurring trachoma (21%) and trachomatous trichiasis (14.3%). Trachoma and NCDs clustered together in <1 km distances (R=0.18, p=0.02). In network analysis, age was strongly associated with trachoma and NCDs. Trachoma was linked with geographic location while diabetes was linked with water source distances. Education level became the central risk factor.

Conclusions

We demonstrate a twin trachoma–NCD burden that is higher among elderly pastoralists in southern Kenya. Attenuating adverse population-level visual impairment, including integrating the trachoma SAFE strategy with NCD comprehensive care, amplifies the benefits from economies of scale, accelerating realization of Sustainable Development Goal 3 and universal health coverage in hard-to-reach areas.
P01 The Australian experience of adapting and implementing ‘To Dip or Not to Dip’ in residential aged care facilities
Authors: Lim Lyn-li , Wroth Melanie , Williams Kathleen , Breen Juanita
Published: August 2023

Objectives

‘To Dip or Not to Dip’ (TDONTD) is a behavioural intervention focused on reducing inappropriate antibiotic prescribing for urinary tract infections (UTI) by changing urine dipstick testing practice. It was adapted by the Aged Care Quality and Safety Commission from a successful initiative in England’s care homes. We describe TDONTD adaptation and evaluation of TDONTD to support improvement in UTI management in Australian residential aged care facilities.

Methods

Data were collected in 12 facilities, from November 2021 to July 2022. Baseline and 3 month interviews were conducted with nurse and pharmacist champions implementing TDONTD and antibiotic prescribing audits.

Results

Australia’s most widely accepted national guideline for assessment of residents with suspected UTI discourages urine testing in asymptomatic persons, however, is not explicit on when to (or not) perform dipstick testing in residents who do not meet minimum criteria for UTI. We adapted key resources including case-based education, clinical pathway for assessing residents for suspected UTI and antibiotic audit tool to incorporate national guideline recommendations around dipstick testing. Surveys with nurse champions of urine dipstick practice showed improved practice in the facilities related to reduced testing for asymptomatic bacteriuria (ASB) and increased use of formal protocol to guide dipstick testing practice and UTI diagnosis. Qualitative interviews with champions identified: (i) increased knowledge around ASB, clinical signs and symptoms of suspected UTI; (ii) increased confidence in not relying on dipstick testing to diagnose suspected UTI; (iii) TDONTD challenged and changed nurse perceptions of how residents present with UTI; (iv) pressure from external healthcare professional providers and family to perform dipstick testing was common; and (v) TDONTD was a feasible intervention in Australian RACF setting. Oral antibiotic prescribing for all indications, including UTI, improved with the intervention as did prescribing appropriateness for UTI treatment but not prophylaxis (Table 1). Table 1.Oral antibiotic prescriptions for UTI at baseline, 3 months and 6 monthsOral antibiotic prescriptionsBaseline (%), 1074 residents3 months (%), 1054 residents6 months (%), 634 residentsFor all indications7.95.25.1For UTI32.61.6By appropriateness (indication and duration) For UTI treatment2758100 For UTI prophylaxis61814

Conclusions

We found that TDONTD supported improved clinical management of residents with suspected UTI in an Australian aged care setting. Knowledge, skills and environmental context and resources contributed towards practice change. External healthcare professional providers and family were barriers to change suggesting that education around dipstick testing should be expanded to broader community and hospital healthcare settings in Australia.
Diagnostic concordance among nursing clinical decision support system users: a pilot study
Authors: dos Santos Diogo Regina Célia , Silva Butcher Rita de Cassia Gengo e , Peres Heloísa Helena Ciqueto
Published: August 2023

Objective

To analyze the nursing diagnostic concordance among users of a clinical decision support system (CDSS), The Electronic Documentation System of the Nursing Process of the University of São Paulo (PROCEnf-USP®), structured according to the Nanda International, Nursing Intervention Classification and Nursing Outcome Classification (NNN) Taxonomy.

Materials and Methods

This pilot, exploratory-descriptive study was conducted from September 2017 to January 2018. Participants were nurses, nurse residents, and nursing undergraduates. Two previously validated written clinical case studies provided participants with comprehensive initial assessment clinical data to be registered in PROCEnf-USP®. After having registered the clinical data in PROCEnf-USP®, participants could either select diagnostic hypotheses offered by the system or add diagnoses not suggested by the system. A list of nursing diagnoses documented by the participants was extracted from the system. The concordance was analyzed by Light’s Kappa (K).

Results

The research study included 37 participants, which were 14 nurses, 10 nurse residents, and 13 nursing undergraduates. Of the 43 documented nursing diagnoses, there was poor concordance (K = 0.224) for the diagnosis “Ineffective airway clearance” (00031), moderate (K = 0.591) for “Chronic pain” (00133), and elevated (K = 0.655) for “Risk for unstable blood glucose level” (00179). The other nursing diagnoses had poor or no concordance.

Discussion

Clinical reasoning skills are essential for the meaningful use of the CDSS.

Conclusions

There was concordance for only 3 nursing diagnoses related to biological needs. The low level of concordance might be related to the clinical judgment skills of the participants, the written cases, and the sample size.
Interference of the novel designer benzodiazepine 4ʹ-chloro deschloroalprazolam with alprazolam analysis in toxicology and seized drug DUID casework
Authors: Reber Jami D , Rodgers Corissa , Ayala Jessica L , Miller James , Stout Peter , Lee Dayong
Published: August 2023

In recent years, the emergence of the novel designer benzodiazepine 4ʹ-chloro deschloroalprazolam has presented a new challenge for forensic laboratories by interfering with the identification and quantitation of alprazolam. As an isomer of alprazolam, 4ʹ-chloro deschloroalprazolam has similar physicochemical properties and can be misidentified in casework samples as alprazolam without a specific method to differentiate the two analytes. Starting in late 2021, the Houston Forensic Science Center (HFSC) received toxicological and seized drug evidence indicating the presence of 4ʹ-chloro deschloroalprazolam. An interference study was performed to supplement the laboratory’s validated benzodiazepines method for toxicological samples to differentiate alprazolam from 4ʹ-chloro deschloroalprazolam. This study showed that while the isomers could not be chromatographically resolved using the current method, they could be differentiated based on their retention times relative to the internal standard, alprazolam-d5. Based on these findings, the HFSC toxicology laboratory reports test results as “unsuitable for analysis due to an interference” if a suspected alprazolam peak elutes before the alprazolam-d5 peak, even if all identification and quantification criteria (e.g., retention time) were acceptable. Additionally, the seized drug and toxicology laboratories re-evaluated previously analyzed alprazolam-positive casework to determine if suspected 4ʹ-chloro deschloroalprazolam had been misidentified as alprazolam. This report presents three cases: one case with toxicological evidence indicating the presence of both 4ʹ-chloro deschloroalprazolam and alprazolam, and two cases with both seized drug material and toxicology evidence indicating the presence of 4ʹchloro deschloroalprazolam with no detected alprazolam.
Comparative toxicology of syringe exchange and postmortem blood samples in the District of Columbia: Trends and affinity analysis
Authors: Turley Ben , Evans Alexandra , Benzio Katharine
Published: August 2023

This cross-sectional analysis aimed to understand the similarities and differences between drugs detected in syringes collected from syringe service providers in the District of Columbia and fatal overdose deaths captured by the State Unintentional Drug Overdose Reporting System. Substance exposures for these fatal and non-fatal drug use outcomes have not been previously compared. Substance distributions were examined and a paired significance test was used to compare changes over time. Affinity analysis was employed to reveal substance co-occurrences. Between September 2020 and September 2022, 1,118 postmortem blood samples (PBSs) and 3,646 syringes exchange samples (SESs) were processed, with fatal overdoses increasing 24.1%. Polysubstance use was more commonly found in postmortem blood (82.5%) than in syringe samples (48.6%). Of samples containing opioids, 94.8% of blood samples and 86.3% of syringes contained fentanyl, fentanyl analogs or fentanyl precursors/metabolites. PBSs had double the frequency of co-occurring stimulants and opioids (43.9%) as SESs (21.8%). Major changes in occurrence frequency over time were found for opioid and stimulant exposure in both groups, especially in the increased occurrence of fluorofentanyl (>400%), methamphetamine (>90%) and xylazine (>60%), while the incidence of fentanyl, heroin and metabolite morphine declined. These results indicate that while fatal use and syringe exchange populations have distinct substance exposures, which may contribute to differences in mortality rate, their substance distributions have similar change magnitudes. This study highlights the utility of using multiple data sources to provide a comprehensive description of drug use patterns and discusses the limitations in reporting data from each source.
Urban ash management and emerald ash borer (Coleoptera: Buprestidae): facts, myths, and an operational synthesis
Authors: Sadof Clifford S , McCullough Deborah G , Ginzel Matthew D
Published: August 2023

Survival of North American species of ash (Oleaceae: Fraxinus spp. L.) is threatened by emerald ash borer (EAB), Agrilus planipennis (Fairmaire), a phloem-feeding beetle that destroys the vascular system of its host. In forested sites where ash is a dominant overstory species, mortality caused by EAB can substantially alter conditions, with potentially cascading effects on ecosystems. In urban forests, ash trees were often abundant and provided an array of ecosystem services because of their rapid growth, capacity to withstand stressful urban conditions and prior to EAB, low pest load. Annualized costs of managing EAB on urban ash trees over the next 30 yr in the United States has been estimated to approach $1.8 billion. Numerous cost-benefit analyses have demonstrated that it is more cost effective to retain mature ash trees with systemic insecticides than to replace these trees in urban areas. Effective protection of urban ash trees depends on deployment of systemic insecticides before EAB injury disrupts the vascular system that transports insecticide to the canopy. Given the ongoing spread of EAB, timely management is critical for protecting urban ash canopies. Over the last 2 decades, we have encountered persistent myths that have hindered the adoption of protective measures to preserve urban ash in communities recently infested by EAB. Here we review these myths and counter them with research-based evidence that supports and justifies an ash management program. Finally, we use the 5 basic tenets of IPM to outline an approach for managing EAB in urban forests.
The analysis of fecal calprotectin as a diagnostic marker for anastomotic leakage after rectal cancer surgery: a pilot study
Authors: Hiraki Masatsugu , Tanaka Toshiya , Sato Hirofumi , Miyake Shuusuke , Kubo Hiroshi , Shinkai Yukio , Sadashima Eiji , Kitahara Kenji
Published: July 2023

A prospective pilot study was conducted on 11 patients with rectal cancer to investigate fecal calprotectin (FC) as a diagnostic tool for detecting anastomotic leakage (AL) after low anterior resection. Among the 11 patients, 1 patient (9.1%) experienced AL (Clavien-Dindo Grade IIIa). During the post-operative course until post-operative day (POD) 5, the white blood cell count of the patient with AL was within the normal range. The C-reactive protein level in the AL and non-AL groups showed a similar time course. On the other hand, the FC level in patient with AL dramatically increased on POD5, while the FC level of the non-AL group remained relatively stable. There was no significant correlation between the preoperative FC level and the tumor circumference rate, tumor size, depth of invasion or stage. This pilot study showed the possibility of FC as a useful diagnostic tool for the detection of AL after low anterior resection for rectal cancer.
A MeerKAT-meets-LOFAR study of Abell 1413: a moderately disturbed non-cool-core cluster hosting a ~500 kpc ‘mini’-halo
Authors: Riseley C J , Biava N , Lusetti G , Bonafede A , Bonnassieux E , Botteon A , Loi F , Brunetti G , Cassano R , Osinga E , Rajpurohit K , Röttgering H J A , Shimwell T , Timmerman R , van Weeren R J
Published: August 2023

Many relaxed cool-core clusters host diffuse radio emission on scales of hundreds of kiloparsecs: mini-haloes. However, the mechanism responsible for generating them, as well as their connection with central active galactic nuclei, is elusive and many questions related to their physical properties and origins remain unanswered. This paper presents new radio observations of the galaxy cluster Abell 1413 performed with MeerKAT (L-band; 872 to 1712 MHz) and LOFAR HBA (120 to 168 MHz) as part of a statistical and homogeneous census of mini-haloes. Abell 1413 is unique among mini-halo clusters as it is a moderately disturbed non-cool-core cluster. Our study reveals an asymmetric mini-halo up to 584 kpc in size at 1283 MHz, twice as large as first reported at similar frequencies. The spectral index is flatter than previously reported, with an integrated value of α = −1.01 ± 0.06, shows significant spatial variation, and a tentative radial steepening. We studied the point-to-point X-ray/radio surface brightness correlation to investigate the thermal/non-thermal connection: our results show a strong connection between these components, with a superlinear slope of $b = 1.63^{+0.10}_{-0.10}$ at 1283 MHz and $b = 1.20^{+0.13}_{-0.11}$ at 145 MHz. We also explore the X-ray surface brightness/radio spectral index correlation, finding a slope of $b = 0.59^{+0.11}_{-0.11}$. Both investigations support the evidence of spectral steepening. Finally, in the context of understanding the particle acceleration mechanism, we present a simple theoretical model which demonstrates that hybrid scenarios – secondary electrons (re-)accelerated by turbulence – reproduce a superlinear correlation slope.
High-resolution VLBI astrometry of pulsar scintillation screens with the θ - θ transform
Authors: Baker Daniel , Brisken Walter , van Kerkwijk Marten H , van Lieshout Rik , Pen Ue-Li
Published: August 2023

The recent development of $\theta - \theta$ techniques in pulsar scintillometry has opened the door for new high-resolution imaging techniques of the scattering medium. By solving the phase retrieval problem and recovering the wavefield from a pulsar dynamic spectrum, the Doppler shift, time delay, and phase offset of individual images can be determined. However, the results of phase retrieval from a single dish are only known up to a constant phase rotation, which introduces extra parameters when doing astrometry using very long baseline interferometry. We present an extension to previous $\theta - \theta$ methods using the interferometric visibilities between multiple stations to calibrate the wavefields. When applied to existing data for PSR B0834+06, we measure the effective screen distance and lens orientation with five times greater precision than was possible in previous work.
Dynamical friction and feedback on galactic bars in the general fast–slow regime
Authors: Chiba Rimpei
Published: August 2023

Current theories of dynamical friction on galactic bars are based either on linear perturbation theory, which is valid only in the fast limit where the bar changes its pattern speed rapidly, or on adiabatic theory, which is applicable only in the slow limit where the bar’s pattern speed is near-constant. In this paper, we study dynamical friction on galactic bars spinning down at an arbitrary speed, seamlessly connecting the fast and slow limits. We treat the bar–halo interaction as a restricted N-body problem and solve the collisionless Boltzmann equation using the fast-angle-averaged Hamiltonian. The phase-space distribution and density wakes predicted by our averaged model are in excellent agreement with full 3D simulations. In the slow regime where resonant trapping occurs, we show that, in addition to the frictional torque, angular momentum is transferred directly due to the migration of the trapped phase-space: trapped orbits comoving with the resonance typically gain angular momentum, while untrapped orbits leaping over the trapped island lose angular momentum. Due to the negative gradient in the distribution function, gainers typically outnumber the losers, resulting in a net negative torque on the perturber. Part of this torque due to the untrapped orbits was already identified by Tremaine and Weinberg, who named the phenomenon dynamical feedback. Here, we derive the complete formula for dynamical feedback, accounting for both trapped and untrapped orbits. Using our revised formula, we show that dynamical feedback can account for up to 30 per cent of the total torque on the Milky Way’s bar.
The exploration of the soft X-ray excess in FSRQ 4C+21.35 during the 2014 X-ray flare
Authors: Zhao Keqin , Yin Hongxing , Hu Shaoming , Huang Shifeng , Qiao Erlin , Cheng Huaqing , Chen Xu , Xu Jingran
Published: August 2023

We report the soft X-ray excess feature and an opposite tendency between the optical/UV and X-ray bands during the flare that occurred in 2014 in flat-spectrum radio quasar (FSRQ) 4C+21.35 with the observations by Swift-XRT and Swift-UVOT. These unusual phenomena are rarely reported in FSRQs. The flare was covered from the optical to the X-ray while no prominent activity in the γ-ray was observed, which could be an indication of weaker jet activity during the flare. We carry out the spectral energy distribution ranging from the optical to X-ray based on four models which are the warm corona model (Model-1), the relativistic reflection model (Model-2), the corona with the jet model (Model-3), and the relativistic reflection with the jet model (Model-4). We find some extreme variation of the parameters in Model-2 and Model-4 and they are unable to explain the correlations between the optical/UV and X-ray bands. Model-1 and Model-3 can obtain reasonable parameters and provide an explanation for the observed opposite tendency between the optical/UV and X-ray bands. However, considering the weak jet activity during the X-ray flare, Model-1 is much preferred for describing the soft X-ray excess, hard X-ray emission, as well as the opposite tendency between the optical/UV and X-rays. Based on Model-1, it is suggested that the flare in 2014 is probably due to the variation of the geometry of the corona, which is expected to be more strictly tested with further observations in the future.
Towards a reliable prediction of the infrared spectra of cosmic fullerenes and their derivatives in the JWST era
Authors: Xu Jianzhi , Li Aigen , Li Xiaohu , Hou Gao-Lei
Published: August 2023

Fullerenes, including C60, C70, and C60+, are widespread in space through their characteristic infrared vibrational features (C60+ also reveals its presence in the interstellar medium through its electronic transitions) and offer great insights into carbon chemistry and stellar evolution. The potential existence of fullerene-related species in space has long been speculated and recently put forward by a set of laboratory experiments of C60+, C60H+, C60O+, C60OH+, C70H+, and [C60-Metal]+ complexes. The advent of the JWST provides a unique opportunity to search for these fullerene-related species in space. To facilitate JWST search, analysis, and interpretation, accurate knowledge of their vibrational properties is essential. Here, we compile a VibFullerene database and conduct a systematic theoretical study on those species. We derive a set of range-specific scaling factors for vibrational frequencies to account for the deficiency of density functional theory calculations in predicting accurate frequencies. Scaling factors with low root-mean-square and median errors for the frequencies are obtained, and their performance is evaluated, from which the best-performing methods are recommended for calculating the infrared spectra of fullerene derivatives that balance the accuracy and the computational cost. Finally, the recommended vibrational frequencies and intensities of fullerene derivatives are presented for future JWST detection.
The evolution of relative frequencies of ONe and CO SNe Ia
Authors: Bogomazov A I , Tutukov A V
Published: August 2023

In this population synthesis work, we study a variety of possible origin channels of supernovae type Ia (SNe Ia). Among them mergers of carbon–oxygen (CO) and oxygen–neon (ONe) white dwarfs (WDs) under the influence of gravitational waves are considered as the primary channel of SNe Ia formation. We estimated frequencies of mergers of WDs with different chemical compositions and distributions of masses of merging WDs. We computed the dependence of the ratio of merger frequencies of ONe and CO WDs as primaries in corresponding binaries on time. The scatter of masses of considered sources (up to the factor 1.5–2) of SNe Ia is important and should be carefully studied with other sophisticated methods from theoretical point of view. Our ‘game of parameters’ potentially explains the increased dimming of SNe Ia in the redshift range z ≈ 0.5–1 by the changes in the ratio of ONe and CO WDs, i.e. to describe the observed accelerated expansion of the Universe in terms of the evolution of properties of SNe Ia instead of cosmological explanations. This example shows the extreme importance of theoretical studies of problems concerning SNe Ia, because evolutionary scenario and parameter games in nature potentially lead to confusions in their empirical standardization and, therefore, they can influence on cosmological conclusions.
MIGHTEE-H i: the MH i – M* relation over the last billion years
Authors: Pan Hengxing , Jarvis Matt J , Santos Mario G , Maddox Natasha , Frank Bradley S , Ponomareva Anastasia A , Prandoni Isabella , Kurapati Sushma , Baes Maarten , Piña Pavel E Mancera , Rodighiero Giulia , Meyer Martin J , Davé Romeel , Sharma Gauri , Rajohnson Sambatriniaina H A , Adams Nathan J , Bowler Rebecca A A , Sinigaglia Francesco , van der Hulst Thijs , Hatfield Peter W , Sekhar Srikrishna , Collier Jordan D
Published: August 2023

We study the $M_{\rm H\, {\small {I}}}-M_{\star }$ relation over the last billion years using the MIGHTEE-H i sample. We first model the upper envelope of the $M_{\rm H\, {\small {I}}}-M_{\star }$ relation with a Bayesian technique applied to a total number of 249 H i-selected galaxies, without binning the data sets, while taking account of the intrinsic scatter. We fit the envelope with both linear and non-linear models, and find that the non-linear model is preferred over the linear one with a measured transition stellar mass of log10(M⋆/M⊙) = 9.15 ± 0.87, beyond which the slope flattens. This finding supports the view that the lack of H i gas is ultimately responsible for the decreasing star formation rate observed in the massive main-sequence galaxies. For spirals alone, which are biased towards the massive galaxies in our sample, the slope beyond the transition mass is shallower than for the full sample, indicative of distinct gas processes ongoing for the spirals/high-mass galaxies from other types with lower stellar masses. We then create mock catalogues for the MIGHTEE-H i detections and non-detections with two main galaxy populations of late- and early-type galaxies to measure the underlying $M_{\rm H\, {\small {I}}}-M_{\star }$ relation. We find that the turnover in this relation persists whether considering the two galaxy populations as a whole or separately. We note that an underlying linear relation could mimic this turnover in the observed scaling relation, but a model with a turnover is strongly preferred. Measurements on the logarithmic average of H i masses against the stellar mass are provided as a benchmark for future studies.
Nucleosynthesis in outflows of compact objects and detection prospects of associated kilonovae
Authors: Ekanger Nick , Bhattacharya Mukul , Horiuchi Shunsaku
Published: August 2023

We perform a comparative analysis of nucleosynthesis yields from binary neutron star (BNS) mergers, black hole-neutron star (BHNS) mergers, and core-collapse supernovae (CCSNe) with the goal of determining which are the most dominant sources of r-process enrichment observed in stars. We find that BNS and BHNS binaries may eject similar mass distributions of robust r-process nuclei post-merger (up to third peak and actinides, A ∼ 200−240), after accounting for the volumetric event rates. Magnetorotational (MR) CCSNe likely undergo a weak r-process (up to A ∼ 140) and contribute to the production of light element primary process (LEPP) nuclei, whereas typical thermal, neutrino-driven CCSNe only synthesize up to first r-process peak nuclei (A ∼ 80−90). We also find that the upper limit to the rate of MR CCSNe is $\lesssim 1~{{\ \rm per\ cent}}$ the rate of typical thermal CCSNe; if the rate was higher, then weak r-process nuclei would be overproduced. Although the largest uncertainty is from the volumetric event rate, the prospects are encouraging for confirming these rates in the next few years with upcoming surveys. Using a simple model to estimate the resulting kilonova light curve from mergers and our set of fiducial merger parameters, we predict that ∼7 BNS and ∼2 BHNS events will be detectable per year by the Vera C. Rubin Observatory (LSST), with prior gravitational wave (GW) triggers.
Mapping gravity in stellar nurseries – establishing the effectiveness of 2D acceleration maps
Authors: He Zhen-Zhen , Li Guang-Xing , Burkert Andreas
Published: August 2023

Gravity is the driving force of star formation. Although gravity is caused by the presence of matter, its role in complex regions is still unsettled. One effective way to study the pattern of gravity is to compute the accretion it exerts on the gas by providing gravitational acceleration maps. A practical way to study acceleration is by computing it using 2D surface density maps, yet whether these maps are accurate remains uncertain. Using numerical simulations, we confirm that the accuracy of the acceleration maps a2D(x, y) computed from 2D surface density are good representations for the mean acceleration weighted by mass. Due to the underestimations of the distances from projected maps, the magnitudes of accelerations will be overestimated $|\mathbf {a}_{\rm 2D}(x,y)| \approx 2.3 \pm 1.8 \,\, |\mathbf {a}_{\rm 3D}^{\rm proj}(x,y)|$, where $\mathbf {a}_{\rm 3D}^{\rm proj}(x,y)$ is mass-weighted projected gravitational acceleration, yet a2D(x, y) and $\mathbf {a}_{\rm 3D}^{\rm proj}(x,y)$ stay aligned within 20°. Significant deviations only occur in regions where multiple structures are present along the line of sight. The acceleration maps estimated from surface density provide good descriptions of the projection of 3D acceleration fields. We expect this technique useful in establishing the link between cloud morphology and star formation, and in understanding the link between gravity and other processes such as the magnetic field. A version of the code for calculating surface density gravitational potential is available at https://github.com/zhenzhen-research/phi_2d.
The clustering properties of high-redshift passive galaxies
Authors: Magliocchetti M , Santini P , Merlin E , Pentericci L
Published: August 2023

We investigate the clustering properties of 3 < z < 5 candidate passive galaxies from the Merlin et al. (2019) sample residing in the GOODS-North (35 sources) and GOODS-South (33 sources) fields. Within the large uncertainties due to the paucity of sources we do not detect clustering signal in GOODS-North, while this is present in GOODS-South, highlighting the importance of the effects of cosmic variance. The estimated correlation length in GOODS-South is $r_0=12^{+4}_{-5}$ Mpc, while the estimated minimum mass for a halo capable to host one of such high-redshift quenched galaxies is log10(Mmin/M⊙) = 13.0 ± 0.3, once also the constraints from their space density are taken into account. Both values are compatible with the results from GOODS-North. Putting the above findings in a cosmological context, these suggest no evolution of the dark matter content of the hosts of passive galaxies during the past 12.5 Gyr, i.e. during more than 90 per cent of the age of the Universe. We discuss possible scenarios for the observed trend.
The innermost jet in the hidden ultra-luminous X-ray source Cygnus X-3
Authors: Yang Jun , García Federico , del Palacio Santiago , Spencer Ralph , Paragi Zsolt , Castro Segura Noel , Gong Biping , Cao Hongmin , Chen Wen
Published: August 2023

Cygnus X-3 is a high-mass X-ray binary with a compact object accreting matter from a Wolf–Rayet donor star. Recently, it has been revealed by the Imaging X-ray Polarimetry Explorer (IXPE) as a hidden Galactic ultra-luminous X-ray (ULX) source with a luminosity above the Eddington limit, along the direction of a narrow (opening angle $\lesssim 32^{\circ }$) funnel. In between the IXPE observations, we observed Cyg X-3 with the European very long baseline interferometry (VLBI) Network at 22 GHz and the NICER X-ray instrument. To probe possible relations between the X-ray funnel and the potential radio jet from the ULX, we analysed the simultaneous multiwavelength data. Our high-resolution VLBI image reveals an elongated structure with a position angle of −3.2 ± 0.4 °, accurately perpendicular to the direction of the linear X-ray polarization. Because Cyg X-3 was in the radio quiescent state on 2022 November 10, we identify the mas-scale structure as the innermost radio jet. The finding indicates that the radio jet propagates along and within the funnel. Moreover, the jet is marginally resolved in the transverse direction. This possibly results from the strong stellar winds and the rapid orbital motion of the binary system.
Chemical transformations of arsenic in the rhizosphere–root interface of Pityrogramma calomelanos and Pteris vittata
Authors: Corzo Remigio Amelia , Harris Hugh H , Paterson David J , Edraki Mansour , van der Ent Antony
Published: August 2023

Pityrogramma calomelanos and Pteris vittata are cosmopolitan fern species that are the strongest known arsenic (As) hyperaccumulators, with potential to be used in the remediation of arsenic-contaminated mine tailings. However, it is currently unknown what chemical processes lead to uptake of As in the roots. This information is critical to identify As-contaminated soils that can be phytoremediated, or to improve the phytoremediation process. Therefore, this study identified the in situ distribution of As in the root interface leading to uptake in P. calomelanos and P. vittata, using a combination of synchrotron micro-X-ray fluorescence spectroscopy and X-ray absorption near-edge structure imaging to reveal chemical transformations of arsenic in the rhizosphere–root interface of these ferns. The dominant form of As in soils was As(V), even in As(III)-dosed soils, and the major form in P. calomelanos roots was As(III), while it was As(V) in P. vittata roots. Arsenic was cycled from roots growing in As-rich soil to roots growing in control soil. This study combined novel analytical approaches to elucidate the As cycling in the rhizosphere and roots enabling insights for further application in phytotechnologies to remediated As-polluted soils.
Assessment of natural radioactivity levels in soil samples from Dejen district, Ethiopia
Authors: Cherie Gizachew Z , Deressu Tilahun T
Published: August 2023

Gamma ray spectrometry was used to determine the activity concentrations of naturally occurring radionuclides in 12 soil samples collected at random from Dejen district, Ethiopia. In agricultural soils, the calculated mean activity concentrations of 226Ra, 232Th and 40K were 33.44 ± 2.01, 66.02 ± 4.54 and 214.16 ± 8.90 Bq kg−1, respectively, and in virgin soils, they were 38.05 ± 2.48, 61.78 ± 4.76 and 240.32 ± 10.79 Bq kg−1, respectively. The findings were discussed and compared to other studies’ findings. The mean values of absorbed dose rate, annual effective dose rate and radium equivalent activity in agricultural land soils are 67.24 nGyh−1, 0.083 mSvy−1 and 144.57 Bq kg−1, and in virgin land soils are 67.53 nGyh−1, 0.082 mSvy−1 and 144.90 Bq kg−1, respectively. These findings were discussed and compared to the internationally recommended value. As a result, it is possible to conclude that the soil samples are safe for residents and those involved in agricultural activities.
Amygdala resting-state functional connectivity alterations in patients with chronic insomnia disorder: correlation with electroencephalography beta power during sleep
Authors: Kweon Woojin , Lee Kyung Hwa , Choi Sang Ho , Shin Jiyoon , Seo Mincheol , Jeon Jeong Eun , Lee Ha Young , Park Chowon , Kim Sun-Young , Kim Jong Won , Chang Jun Hyuk , Lee Yu Jin
Published: August 2023

Study Objectives

This study investigated alterations in resting-state functional connectivity (RSFC) and hyperarousal biomarkers in patients with chronic insomnia disorder (CID), compared with good sleepers (GS). We also examined the relationships between altered RSFC and hyperarousal biomarkers.

Methods

Fifty patients with CID and 52 GS completed self-reporting questionnaires, and then underwent polysomnography and resting-state functional magnetic resonance imaging. We analyzed RSFC in the amygdala (AMG) and anterior insula (aINS), which are core regions of the salience network that are likely to be involved in hyperarousal. We also analyzed electroencephalography (EEG) relative beta power and heart rate variability (HRV) parameters (e.g. low and high frequency) during sleep. We then tested between-group differences in the RSFC and hyperarousal biomarkers; we examined correlations of RSFC with EEG beta power and HRV.

Results

Compared with GS, patients with CID showed more negative RSFC between the right amygdala (R.AMG) and left supramarginal gyrus (L.SMG), but less positive RSFC between the left aINS and bilateral lateral prefrontal cortex. The R.AMG–L.SMG RSFC was negatively correlated with EEG beta power in central regions (C3: r = −0.336, p = 0.012; C4: r = −0.314, p = 0.024).

Conclusions

Decreased RSFC between the R.AMG and L.SMG in patients with insomnia may reflect the difficulty in cortical top-down regulation of the AMG, indicating daytime hyperarousal. Individuals who experience hyperarousal during the daytime may also exhibit cortical hyperarousal during sleep, as indicated by increased EEG beta power.
The effects of closed-loop auditory stimulation on sleep oscillatory dynamics in relation to motor procedural memory consolidation
Authors: Baxter Bryan S , Mylonas Dimitrios , Kwok Kristi S , Talbot Christine E , Patel Rudra , Zhu Lin , Vangel Mark , Stickgold Robert , Manoach Dara S
Published: August 2023

Study Objectives

Healthy aging and many disorders show reduced sleep-dependent memory consolidation and corresponding alterations in non-rapid eye movement sleep oscillations. Yet sleep physiology remains a relatively neglected target for improving memory. We evaluated the effects of closed-loop auditory stimulation during sleep (CLASS) on slow oscillations (SOs), sleep spindles, and their coupling, all in relation to motor procedural memory consolidation.

Methods

Twenty healthy young adults had two afternoon naps: one with auditory stimulation during SO upstates and another with no stimulation. Twelve returned for a third nap with stimulation at variable times in relation to SO upstates. In all sessions, participants trained on the motor sequence task prior to napping and were tested afterward.

Results

Relative to epochs with no stimulation, upstate stimuli disrupted sleep and evoked SOs, spindles, and SO-coupled spindles. Stimuli that successfully evoked oscillations were delivered closer to the peak of the SO upstate and when spindle power was lower than stimuli that failed to evoke oscillations. Across conditions, participants showed similar significant post-nap performance improvement that correlated with the density of SO-coupled spindles.

Conclusions

Despite its strong effects on sleep physiology, CLASS failed to enhance motor procedural memory. Our findings suggest methods to overcome this failure, including better sound calibration to preserve sleep continuity and the use of real-time predictive algorithms to more precisely target SO upstates and to avoid disrupting endogenous SO-coupled spindles and their mnemonic function. They motivate continued development of CLASS as an intervention to manipulate sleep oscillatory dynamics and improve memory.
The causal associations of altered inflammatory proteins with sleep duration, insomnia and daytime sleepiness
Authors: Zhang Yuan , Zhao Wangcheng , Liu Kun , Chen Ziliang , Fei Quanming , Ahmad Namra , Yi Minhan
Published: August 2023

Study Objectives

Growing evidence linked inflammation with sleep. This study aimed to evaluate the associations and causal effects of sleep traits including insomnia, excessive daytime sleepiness (EDS), and sleep duration (short: <7 h; normal: 7–9 h; long: ≥9 h), with levels of C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-α), and interleukins.

Methods

Standard procedures of quantitative analysis were applied to estimate the expression differences for each protein in compared groups. Then, a two-sample Mendelian randomization (MR) analysis was performed to explore their causal relationships with published genome-wide association study summary statistics. The inverse-variance weighted was used as the primary method, followed by several complementary approaches as sensitivity analyses.

Results

A total of 44 publications with 51 879 participants were included in the quantitative analysis. Our results showed that the levels of CRP, interleukin-1β (IL-1β), IL-6, and TNF-α were higher from 0.36 to 0.58 (after standardization) in insomnia compared with controls, while there was no significant difference between participants with EDS and controls. Besides, there was a U/J-shaped expression of CRP and IL-6 with sleep durations. In MR analysis, the primary results demonstrated the causal effects of CRP on sleep duration (estimate: 0.017; 95% confidence intervals [CI], [0.003, 0.031]) and short sleep duration (estimate: −0.006; 95% CI, [−0.011, −0.001]). Also, IL-6 was found to be associated with long sleep duration (estimate: 0.006; 95% CI, [0.000, 0.013]). These results were consistent in sensitivity analyses.

Conclusions

There are high inflammatory profiles in insomnia and extremes of sleep duration. Meanwhile, elevated CRP and IL-6 have causal effects on longer sleep duration. Further studies can focus on related upstream and downstream mechanisms.
Plasma neurofilament light chain as a potential biomarker of neurodegeneration in murine brain
Authors: Sano Tomoya , Masuda Yasushi , Yasuno Hironobu , Shinozawa Tadahiro , Watanabe Takeshi
Published: August 2023

Reliable fluid biomarkers for evaluating neurotoxicity have yet to be established. However, recent studies have reported neurofilament light chain as a fluid biomarker of several neurodegenerative disorders. In this study, we investigated changes in the cerebrospinal fluid and plasma levels of neurofilament light chain in mice treated with trimethyltin as a neurotoxicant. Trimethyltin diluted with saline was administered by intraperitoneal injection to mice at dose levels of 0 (vehicle control), 1.0, and 2.6 mg/kg body weight (dosage volume: 10 mL/kg). At 3 or 7 days after administration, animals were euthanized by exsanguination under 2–3% isoflurane inhalation anesthesia. Increased neurofilament light chain levels in both the cerebrospinal fluid and plasma were observed in animals from the trimethyltin 2.6 mg/kg body weight group, which indicated the brain lesions including neuronal cell death. Animals from the trimethyltin 1.0 mg/kg body weight group exhibited changes neither in neurofilament light chain levels in the cerebrospinal fluid and plasma nor in the histopathology of the brain at any time point. These data indicate that plasma neurofilament light chain can serve as a useful peripheral biomarker for detecting brain lesions such as neuronal necrosis in mice.