bluuebunny/crossref_metadata_2025 huggingface dataset:
Adaptation of von Karman Institute for Fluid Dynamics’ Isentropic Compression Tube Facility for High-Speed Low-Pressure Turbines Testing
Authors: Torre Antonino Federico Maria , Merli Filippo , Valle Lorenzo Da , Patinios Marios , Lavagnoli Sergio , Ludovic Pintat
Published: November 2023

This paper presents the commissioning of a newly designed High-Speed Low-Pressure Turbine (LPT) stage, operating at transonic exit Mach numbers and low Reynolds numbers, typical of modern geared turbofan (GTF) applications. The work falls within the scope of the Clean Sky 2 project SPLEEN (Secondary and Leakage Flow Effects in High-speed Low-pressure Turbines), which consists of an extensive experimental characterization of LPTs for GTFs. Geometries and measurements will constitute a valuable open-access database for the validation of simulation methods and data analysis tools. At first, the characteristics of the research turbine are illustrated. The LPT stage is designed with an equal number of stationary vanes and shrouded rotor blades. The upstream and downstream hub cavities are purged and feature engine-realistic rim seals. The nominal operating condition of the stage is reported, along with a set of off-design conditions, obtained by varying rotor speed and purge mass flows. The second part of the paper describes the substantial revamping of the CT3 large-scale compression tube at Von Karman Institute for Fluid Dynamics, traditionally employed for high-pressure turbine testing, now adapted to host a high-speed LPT stage. The third section is an overview of the time-averaged and fast-response instrumentation. The test article is heavily instrumented, to maximize the amount of acquired data, while minimizing the number of blowdown tests. The dataset for each operating conditions includes aerothermal measurements in the annulus flow, in the hub cavities and in the shroud labyrinth seal. In addition, this section presents the design of an in-house traversing system for continuous probe traversing during the test. Finally, the outcome of the commissioning phase is discussed, with particular emphasis on the operating conditions stability, as well as on the inlet and cavity injection uniformity. The commissioning of a traversing system for continuous probe traversing during the short-duration test is also discussed.
Germanium surface cleaning and ALD of a protective boron nitride overlayer
Authors: Omolere Olatomide B. , Adesope Qasim , Alhowity Samar , Agbara Tochi L. , Kelber Jeffry A.
Published: November 2023

Germanium exhibits superior hole and electron mobility compared with silicon, making it a promising candidate for replacement of silicon in certain future CMOS applications. In such applications, achieving atomically clean Ge surfaces and the subsequent deposition of ultrathin passivation barriers without interfacial reaction are critical. In this study, we present in situ x-ray photoelectron spectroscopy (XPS) investigations of hydrocarbon removal from the Ge surface utilizing atomic oxygen at room temperature, as well as removal of hydrocarbons and of germanium oxide (GeO2) through atomic hydrogen treatment at 350 °C. Subsequently, atomic layer deposition (ALD) was used to create a protective layer of hexagonal boron nitride (h-BN) with an average thickness of 3 monolayers (ML). Tris(dimethylamino)borane and ammonia precursors were utilized at 450 °C for the deposition process. Intermittent in situ XPS analysis during ALD confirmed h-BN growth, stoichiometry, and the absence of interfacial reaction with Ge. XPS analysis after subsequent exposure of the Ge film with a h-BN overlayer of ∼9 Å average thickness to 7.2 × 104 l of atomic O (O3P) at room temperature yielded no evidence of Ge oxidation, with only the surface layer of the h-BN film exhibiting oxidation. These results present a practical and scalable route toward the preparation of clean Ge surfaces and subsequent deposition of protective, nanothin h-BN barriers for subsequent processing.
Modeling and interpretation of bistatic bottom reverberation in deep water near seamounts
Authors: Guo Yue , Duan Rui , Zhang Hao , Yang Kunde , Liu Tianhe , Gong Guangyu
Published: November 2023

The received reverberation signal can be beamformed by utilizing a vertical array, generating a vertical-angle time record (VATR) that enables analysis of spatiotemporal distribution characteristics. Due to the influence of multipath propagation effects, deep-sea reverberation exhibits highly complex characteristics, especially in a seabed with significant depth variation. In a recent bistatic reverberation experiment with a vertical array receiver, peculiar bright stripes were observed in the VATR. These stripes are the result of scattering caused by large-scale bottom structures and are closely associated with seamounts. To accurately model and interpret these stripes, a bistatic reverberation model is initially established to reproduce the VATR. This model enables us to numerically simulate the spatiotemporal distribution of reverberation in the VATR, offering a qualitative explanation for these stripes. However, the model alone is incapable of predicting the specific stripe structure associated with a particular seamount. To address this limitation, an equation system is introduced to calculate the stripe parameters based on the seamount parameters. By analyzing and deducing the dependency of the stripes on the seamount, conclusions were drawn using the equation system. Ultimately, the presented model and equation system successfully reproduce and comprehensively explain the observed abnormal stripes from the experiment.
Optimal audio beam pattern synthesis for an enhanced parametric array loudspeaker
Authors: Zhu Yunxi , Ma Wenyao , Kuang Zheng , Wu Ming , Yang Jun
Published: November 2023

A parametric array loudspeaker (PAL) generates highly directional audible sound in air with a small aperture size compared to a conventional loudspeaker. But in indoor applications, the long propagation distance of a PAL causes reflections, which disturbs the reproduction of narrow audio beams. Moreover, sound distortion appears along the off-axis direction due to the frequency dependence of the beam width. This study proposed an optimal audio beam pattern synthesis for a PAL-based convex optimization, which can design the audio beam of a PAL with an optimal solution. The proposed method overcame the mentioned limitations by applying it to a length-limited PAL for audio spot control and a multichannel PAL array for a constant beam width audio beam. In a length-limited PAL, the proposed method restricts the audio spot to a smaller region and weakens the sound leakage along the off-axis direction. Whereas in a multichannel PAL array, the proposed method also achieves a constant beam width near the radiator axis. Simulations and experiments verify the effectiveness of the proposed method, which will enhance the performance of a PAL in scenarios where control of the audio beam is required.
A tool kit of highly selective and sensitive genetically encoded neuropeptide sensors
Authors: Wang Huan , Qian Tongrui , Zhao Yulin , Zhuo Yizhou , Wu Chunling , Osakada Takuya , Chen Peng , Chen Zijun , Ren Huixia , Yan Yuqi , Geng Lan , Fu Shengwei , Mei Long , Li Guochuan , Wu Ling , Jiang Yiwen , Qian Weiran , Zhang Li , Peng Wanling , Xu Min , Hu Ji , Jiang Man , Chen Liangyi , Tang Chao , Zhu Yingjie , Lin Dayu , Zhou Jiang-Ning , Li Yulong
Published: November 2023

Neuropeptides are key signaling molecules in the endocrine and nervous systems that regulate many critical physiological processes. Understanding the functions of neuropeptides in vivo requires the ability to monitor their dynamics with high specificity, sensitivity, and spatiotemporal resolution. However, this has been hindered by the lack of direct, sensitive, and noninvasive tools. We developed a series of GRAB (G protein–coupled receptor activation‒based) sensors for detecting somatostatin (SST), corticotropin-releasing factor (CRF), cholecystokinin (CCK), neuropeptide Y (NPY), neurotensin (NTS), and vasoactive intestinal peptide (VIP). These fluorescent sensors, which enable detection of specific neuropeptide binding at nanomolar concentrations, establish a robust tool kit for studying the release, function, and regulation of neuropeptides under both physiological and pathophysiological conditions.
Nickel-catalyzed ester carbonylation promoted by imidazole-derived carbenes and salts
Authors: Yoo Changho , Bhattacharya Shrabanti , See Xin Yi , Cunningham Drew W. , Acosta-Calle Sebastian , Perri Steven T. , West Nathan M. , Mason Dawn C. , Meade Chris D. , Osborne Christopher W. , Turner Phillip W. , Kilgore Randall W. , King Jeff , Cowden Jeffrey H. , Grajeda Javier M. , Miller Alexander J. M.
Published: November 2023

Millions of tons of acetyl derivatives such as acetic acid and acetic anhydride are produced each year. These building blocks of chemical industry are elaborated into esters, amides, and eventually polymer materials, pharmaceuticals, and other consumer products. Most acetyls are produced industrially using homogeneous precious metal catalysts, principally rhodium and iridium complexes. We report here that abundant nickel can be paired with imidazole-derived carbenes or the corresponding salts to catalyze methyl ester carbonylation with turnover frequency (TOF) exceeding 150 hour
–1
and turnover number (TON) exceeding 1600, benchmarks that invite comparisons to state-of-the-art rhodium-based systems and considerably surpass known triphenylphosphine-based nickel catalysts, which operate with TOF ~7 hour
–1
and TON ~100 under the same conditions.
Design principles of 3D epigenetic memory systems
Authors: Owen Jeremy A. , Osmanović Dino , Mirny Leonid
Published: November 2023

Cells remember their identities, in part, by using epigenetic marks—chemical modifications placed along the genome. How can mark patterns remain stable over cell generations despite their constant erosion by replication and other processes? We developed a theoretical model that reveals that three-dimensional (3D) genome organization can stabilize epigenetic memory as long as (i) there is a large density difference between chromatin compartments, (ii) modifying “reader-writer” enzymes spread marks in three dimensions, and (iii) the enzymes are limited in abundance relative to their histone substrates. Analogous to an associative memory that encodes memory in neuronal connectivity, mark patterns are encoded in a 3D network of chromosomal contacts. Our model provides a unified account of diverse observations and reveals a key role of 3D genome organization in epigenetic memory.
Solid waste, a lever for decarbonization
Authors: Webber Michael E. , Glazer Yael R.
Published: November 2023

Reducing methane emissions from solid waste is already technically possible
C. R. Rao (1920–2023)
Authors: Banks David , Clarke Jennifer L.
Published: November 2023

Pioneering statistician and father of information geometry
Lessons from sleep in the deep
Authors: Kendall-Bar Jessica
Published: November 2023

Records of seal sleep at sea reveal extreme sleep duration flexibility
In Science Journals
Authors: Smith H. Jesse , Ray L. Bryan , Yeston Jake S. , Norton Melissa L. , Clauset Aaron , Szuromi Phil , Stajic Jelena , Alderton Gemma , Jiang Di , Stern Peter , Grocholski Brent , Lavine Marc S. , Vignieri Sacha , Wong Wei , Olingy Claire
Published: November 2023

Highlights from the
Science
family of journals
Carbon-free fuels could have a climatic dark side
Authors: Bourzac Katherine
Published: November 2023

As nations push for green hydrogen and ammonia, researchers warn of side effects
Optimizing dosing of the cycloserine pro-drug terizidone in children with rifampicin-resistant tuberculosis
Authors: van der Laan Louvina E. , Garcia-Prats Anthony J. , McIlleron Helen , Abdelwahab Mahmoud T. , Winckler Jana L. , Draper Heather R. , Wiesner Lubbe , Schaaf H. Simon , Hesseling Anneke C. , Denti Paolo
Published: November 2023

There are no pharmacokinetic data in children on terizidone, a pro-drug of cycloserine and a World Health Organization (WHO)-recommended group B drug for rifampicin-resistant tuberculosis (RR-TB) treatment. We collected pharmacokinetic data in children <15 years routinely receiving 15–20 mg/kg of daily terizidone for RR-TB treatment. We developed a population pharmacokinetic model of cycloserine assuming a 2-to-1 molecular ratio between terizidone and cycloserine. We included 107 children with median (interquartile range) age and weight of 3.33 (1.55, 5.07) years and 13.0 (10.1, 17.0) kg, respectively. The pharmacokinetics of cycloserine was described with a one-compartment model with first-order elimination and parallel transit compartment absorption. Allometric scaling using fat-free mass best accounted for the effect of body size, and clearance displayed maturation with age. The clearance in a typical 13 kg child was estimated at 0.474 L/h. The mean absorption transit time when capsules were opened and administered as powder was significantly faster compared to when capsules were swallowed whole (10.1 vs 72.6 min) but with no effect on bioavailability. Lower bioavailability (−16%) was observed in children with weight-for-age z-score below -2. Compared to adults given 500 mg daily terizidone, 2022 WHO-recommended pediatric doses result in lower exposures in weight bands 3–10 kg and 36–46 kg. We developed a population pharmacokinetic model in children for cycloserine dosed as terizidone and characterized the effects of body size, age, formulation manipulation, and underweight-for-age. With current terizidone dosing, pediatric cycloserine exposures are lower than adult values for several weight groups. New optimized dosing is suggested for prospective evaluation.
Unraveling the mechanism of ceftaroline-induced allosteric regulation in penicillin-binding protein 2a: insights for novel antibiotic development against methicillin-resistant
Staphylococcus aureus
Authors: Jiao Fangfang , Bao Yiqiong , Li Mengrong , Zhang Yan , Zhang Feng , Wang Pinkai , Tao Jun , Tong Henry H. Y. , Guo Jingjing
Published: November 2023

Methicillin-resistant
Staphylococcus aureus
(MRSA) acquires high-level resistance against β-lactam antibiotics by expressing penicillin-binding protein 2a (PBP2a). PBP2a is a cell wall-synthesizing protein whose closed active site exhibits a reduced binding affinity toward β-lactam antibiotics. Ceftaroline (CFT), a fifth-generation cephalosporin, can effectively inhibit the PBP2a activity by binding to an allosteric site to trigger the active site opening, allowing a second CFT to access the active site. However, the essential mechanism behind the allosteric behavior of PBP2a remains unclear. Herein, computational simulations are employed to elucidate how CFT allosterically regulates the conformation and dynamics of the active site of PBP2a. While CFT stabilizes the allosteric domain surrounding it, it simultaneously enhances the dynamics of the catalytic domain. Specifically, the study successfully captured the opening process of the active pocket in the allosteric CFT-bound systems and discovered that CFT alters the potential signal-propagating pathways from the allosteric site to the active site. These findings reveal the implied mechanism of the CFT-mediated allostery in PBP2a and provide new insights into dual-site drug design or combination therapy against MRSA targeting PBP2a.
Subcutaneous infusion of high-dose benzathine penicillin G is safe, tolerable, and suitable for less-frequent dosing for rheumatic heart disease secondary prophylaxis: a phase 1 open-label population pharmacokinetic study
Authors: Kado Joseph , Salman Sam , Hla Thel K. , Enkel Stephanie , Henderson Robert , Hand Robert M. , Hort Adam , Page-Sharp Madhu , Batty Kevin , Moore Brioni R. , Bennett Julie , Anderson Anneka , Carapetis Jonathan , Manning Laurens
Published: November 2023

Since 1955, the recommended strategy for rheumatic heart disease (RHD) secondary prophylaxis has been benzathine penicillin G [BPG; 1.2 MU (900 mg)] injections administered intramuscularly every 4 weeks. Due to dosing frequency, pain, and programmatic challenges, adherence is suboptimal. It has previously been demonstrated that BPG delivered subcutaneously at a standard dose is safe and tolerable and has favorable pharmacokinetics, setting the scene for improved regimens with less frequent administration. The safety, tolerability, and pharmacokinetics of subcutaneous infusions of high-dose BPG were assessed in 24 healthy adult volunteers assigned to receive either 3.6, 7.2, or 10.8 MU (three, six, and nine times the standard dose, respectively) as a single subcutaneous infusion. The delivery of the BPG to the subcutaneous tissue was confirmed with ultrasonography. Safety assessments, pain scores, and penicillin concentrations were measured for 16 weeks post-dose. Subcutaneous infusion of penicillin (SCIP) was generally well tolerated with all participants experiencing transient, mild infusion-site reactions. Prolonged elevated penicillin concentrations were described using a combined zero-order (44 days) and first-order (
t
1/2
= 12 days) absorption pharmacokinetic model. In simulations, time above the conventionally accepted target concentration of 20 ng/mL (0.02 µg/mL) was 57 days for 10.8 MU delivered by subcutaneous infusion every 13 weeks compared with 9 days of every 4-weekly dosing interval for the standard 1.2 MU intramuscular dose (i.e., 63% and 32% of the dosing interval, respectively). High-dose SCIP (BPG) is safe, has acceptable tolerability, and may be suitable for up to 3 monthly dosing intervals for secondary prophylaxis of RHD.
With a pinch of salt: metagenomic insights into Namib Desert salt pan microbial mats and halites reveal functionally adapted and competitive communities
Authors: Martínez-Alvarez Laura , Ramond Jean-Baptiste , Vikram Surendra , León-Sobrino Carlos , Maggs-Kölling Gillian , Cowan Don A.
Published: November 2023

Salt pans or playas, which are saline-rich springs surrounded by halite evaporates in arid environments, have played an essential role in landscape erosion during the formation of the Namib Desert and are numerous in its central region. In this study, we used shotgun metagenomics to investigate the phylogenetic and functional capacities of the microbial communities from two salt pans (namely, Eisefeld and Hosabes) located in central Namib Desert, located in Southwest Africa. We studied the source and sink sediment mat communities of the saline streams, as well as those from two halites (crystallized structures on the stream margins). The microbial assemblages and potential functions were distinct in both niches. Independently from their localization (Eisfeld vs Hosabes and source vs sink), the sediment mat communities were dominated by members of the
Alpha-
and
Gamma-proteobacteria
classes, while halites were Archaea dominated and also contained high abundances of the extremely halophilic bacterium
Salinibacter
sp. (phylum
Bacteroidota
). Photoheterotrophy and chemoheterotrophy were the principal lifestyles in both niches, with halite communities having a reduced diversity of metabolic pathways. Intense microbial-virus interactions in both niches were implied by the widespread detection of CRISPR-Cas defense systems. We identified a putatively novel clade of type II CRISPR-Cas systems, as well as novel candidate viral lineages of the class Caudoviricetes and of Halobacteriales
-
infecting haloviruses. Putative gene transfer agent-like sequences within the
Alphaproteobacteria
were identified in the sediment mat communities. These horizontal gene transfer elements have the potential to drive genome plasticity and evolution of the
Alphaproteobacteria
in the Namib Desert salt pan microbiomes.

IMPORTANCE

The hyperarid Namib Desert is one of the oldest deserts on Earth. It contains multiple clusters of playas which are saline-rich springs surrounded by halite evaporites. Playas are of great ecological importance, and their indigenous (poly)extremophilic microorganisms are potentially involved in the precipitation of minerals such as carbonates and sulfates and have been of great biotechnological importance. While there has been a considerable amount of microbial ecology research performed on various Namib Desert edaphic microbiomes, little is known about the microbial communities inhabiting its multiple playas. In this work, we provide a comprehensive taxonomic and functional potential characterization of the microbial, including viral, communities of sediment mats and halites from two distant salt pans of the Namib Desert, contributing toward a better understanding of the ecology of this biome.
The potential for development of clinically relevant microbial resistance to rifaximin-α: a narrative review
Authors: DuPont Herbert L.
Published: November 2023

Rifaximin-α is a gut-targeted antibiotic indicated for numerous gastrointestinal and liver diseases. Its multifaceted mechanism of action goes beyond direct antimicrobial effects, including alterations in bacterial virulence, cytoprotective effects on host epithelial cells, improvement of impaired intestinal permeability, and reduction of proinflammatory cytokine expression via activation of the pregnane X receptor. Rifaximin-α is virtually non-absorbed, with low systemic drug levels contributing to its excellent safety profile. While there are high concentrations of drug in the colon, low water solubility leads to low colonic drug bioavailability, protecting the gut microbiome. Rifaximin-α appears to be more active in the bile-rich small bowel. Its important biologic effects are largely at sub-inhibitory concentration. Although
in vitro
testing of clinical isolates from rifaximin recipients has revealed rifaximin-resistant strains in some studies, the risk of emergent rifaximin-α resistance appears to be lower than for many other antibiotics. Rifaximin-α has been used for many years for traveler’s diarrhea with no apparent increase in resistance levels in causative pathogens. Further, rifaximin-α retains its efficacy after long-term and recurrent usage in chronic gastrointestinal disorders. There are numerous reasons why the risk of microbial resistance to rifaximin-α may be lower than that for other agents, including low intestinal bioavailability in the aqueous colon, the mechanisms of action of rifaximin-α not requiring inhibitory concentrations of drug, and the low risk of cross transmission of rifaximin-α resistance between bacterial species. Reported emergence of vancomycin-resistant
Enterococcus
in liver-disease patients maintained on rifaximin needs to be actively studied. Further studies are required to assess the possible correlation between
in vitro
resistance and rifaximin-α efficacy.
Transcription activator-like effectors from endosymbiotic bacteria control the reproduction of their fungal host
Authors: Richter Ingrid , Uzum Zerrin , Wein Philipp , Molloy Evelyn M. , Moebius Nadine , Stinear Timothy P. , Pidot Sacha J. , Hertweck Christian
Published: November 2023

The phytopathogenic fungus
Rhizopus microsporus
harbors a bacterial endosymbiont (
Mycetohabitans rhizoxinica
) that produces a crucial virulence factor responsible for the characteristic symptoms of rice seedling blight. The persistence of this unique microbial alliance is ensured by evasion of fungal defense mechanisms by the resident endosymbionts and their strict control of fungal reproduction. A functional bacterial Type 3 secretion system (T3SS) is essential for the establishment of the symbiosis. Yet, the nature of the effector(s) secreted through the T3SS, and their effects on fungal physiology, has remained elusive. Using bioinformatic analysis, we identified genes encoding potential T3SS effectors, namely an alanine-tryptophan-arginine triad (AWR) peptide and a set of transcription activator-like (TAL) effectors, in the genomes of eight endofungal
Mycetohabitans
strains. Co-culture experiments demonstrated that the sporulating phenotype of apo-symbiotic
R. microsporus
is unaffected upon reinfection with
M. rhizoxinica
Δ
awr
compared to with wild-type
M. rhizoxinica
. In contrast, the ability of apo-symbiotic
R. microsporus
to produce mature sporangiophores when reinfected with
M. rhizoxinica
strains deficient in individual MTALs (
M. rhizoxinica
Δ
mtal1
,
M. rhizoxinica
Δ
mtal2
, and
M. rhizoxinica
Δ
mtal3
) is significantly reduced.
Trans
-complementation experiments showed restoration of fungal sporulation, thus confirming that TAL effectors produced by
M. rhizoxinica
(MTAL1, MTAL2, and MTAL3) are needed for fungal sporulation. Using fluorescence microscopy, we show that AWR- and MTAL-deficient
M. rhizoxinica
strains successfully colonize apo-symbiotic
R. microsporus
, revealing the importance of bacterial MTALs in establishing a stable symbiosis after fungal colonization. Our findings attribute a new function to members of the MTAL family of T3SS-associated effectors and provide deeper insights into host control by prokaryotic symbionts.

IMPORTANCE

Interactions between fungi and bacteria are critically important in ecology, medicine, and biotechnology. In this study, we shed light on factors that promote the persistence of a toxin-producing, phytopathogenic
Rhizopus-Mycetohabitans
symbiosis that causes severe crop losses in Asia. We present an unprecedented case where bacterially produced transcription activator-like (TAL) effectors are key to maintaining a stable endosymbiosis. In their absence, fungal sporulation is abrogated, leading to collapse of the phytopathogenic alliance. The
Mycetohabitans
TAL (MTAL)-mediated mechanism of host control illustrates a unique role of bacterial effector molecules that has broader implications, potentially serving as a model to understand how prokaryotic symbionts interact with their eukaryotic hosts.
Metabolic interactions affect the biomass of synthetic bacterial biofilm communities
Authors: Sun Xinli , Xie Jiyu , Zheng Daoyue , Xia Riyan , Wang Wei , Xun Weibing , Huang Qiwei , Zhang Ruifu , Kovács Ákos T. , Xu Zhihui , Shen Qirong
Published: November 2023

Microbes typically reside in communities containing multiple species, whose interactions have considerable impacts on the robustness and functionality of such communities. To manage microbial communities, it is essential to understand the factors driving their assemblage and maintenance. Even though the community composition could be easily assessed, interspecies interactions during community establishment remain poorly understood. Here, we combined co-occurrence network analysis with quantitative PCR to examine the importance of each species within synthetic communities (SynComs) of pellicle biofilms. Genome-scale metabolic models and
in vitro
experiments indicated that the biomass of SynComs was primarily affected by keystone species that are acting either as metabolic facilitators or as competitors. Our study sets an example of how to construct a SynCom and investigate interspecies interactions.

IMPORTANCE

Co-occurrence network analysis is an effective tool for predicting complex networks of microbial interactions in the natural environment. Using isolates from a rhizosphere, we constructed multi-species biofilm communities and investigated co-occurrence patterns between microbial species in genome-scale metabolic models and in vitro experiments. According to our results, metabolic exchanges and resource competition may partially explain the co-occurrence network analysis results found in synthetic bacterial biofilm communities.
Altered rumen microbiome and correlations of the metabolome in heat-stressed dairy cows at different growth stages
Authors: Feng Lei , Zhang Yu , Liu Wei , Du Dewei , Jiang Wenbo , Wang Zihua , Li Ning , Hu Zhiyong
Published: November 2023

Heat stress is one of the major stressors affecting dairy cow production, which causes great losses in animal husbandry production and economic development. This study combined 16S rDNA sequencing, metagenomic sequencing, and metabolomic analysis to investigate the effects of heat stress on the rumen microbiome and metabolism of cows. To achieve this, 10 cows each of growing heifers, heifers, and lactating cows were selected for sample collection in April and August (a total of 60 cows). Ruminal fluid was collected, filtered through gauze, and immediately transferred to liquid nitrogen prior to metagenomic, 16S rDNA sequencing, and metabolomic analyses. Heat stress increased the abundance of pathogenic bacteria, such as
Treponema_2
,
Sphingobacterium
, and
Streptococcus
, in cattle at all growth stages, with the structure and composition of rumen microbial communities being the most affected by heat stress in growing heifers and the least affected by heat stress in lactating cows. Heat stress led to a significant decrease in carbohydrate metabolic function in growing heifers and heifers, whereas microbial function was the most stable in lactating cows, suggesting that changes in microbial function are not only more conserved than microbial composition but are also affected by age. Heat stress led to significant enrichment of fatty acyl metabolites in growing heifers, heifers, and lactating cows, and the heat stress indicator species
Bacillus
,
Lactococcus
,
Streptococcus
, and
Enterococcus
were significantly associated with fatty acyl compounds in growing heifers and heifers. Therefore, heat stress alters the metabolic status of cows by modulating fatty acid biosynthesis, the PPAR signaling pathway, and arachidonic acid metabolism through the regulation of long-chain fatty acids and other biomarkers in cows at three growth stages.

IMPORTANCE

Heat stress is one of the main causes of economic losses in the dairy industry worldwide; however, the mechanisms associated with the metabolic and microbial changes in heat stress remain unclear. Here, we characterized both the changes in metabolites, rumen microbial communities, and their functional potential indices derived from rumen fluid and serum samples from cows at different growth stages and under different climates. This study highlights that the rumen microbe may be involved in the regulation of lipid metabolism by modulating the fatty acyl metabolites. Under heat stress, the changes in the metabolic status of growing heifers, heifers, and lactating cows were closely related to arachidonic acid metabolism, fatty acid biosynthesis, and energy metabolism. Moreover, this study provides new markers for further research to understand the effects of heat stress on the physiological metabolism of Holstein cows and the time-dependent changes associated with growth stages.
Supplemental Material: Upper crustal seismic velocity structure of the Hayward fault zone, San Francisco Bay, California, USA: Results from the 2016 East Bay Seismic Experiment (EBSI-16)
Authors: Strayer Luther , et al.
Published: November 2023

Starting velocity models, Vp and Vs ray densities, and checkerboard resolution tests.
Outcome data from 15 years of cystic fibrosis newborn screening in a large UK region
Authors: Driscoll Sarah Jane , Heinz Katie , Goddard Philippa , Desai Maya , Gilchrist Francis J
Published: November 2023

Background

The West Midlands Newborn Bloodspot Screening Laboratory is one of 16 in the UK and serves two tertiary paediatric cystic fibrosis (CF) centres (Staffordshire Children’s Hospital at Royal Stoke and Birmingham Children’s Hospital). CF newborn bloodspot screening (NBS) in this region started in November 2006 prior to the UK national roll-out in 2007. It uses an immunoreactive trypsinogen (IRT)/DNA/IRT protocol. We report the outcomes from 15 years of CF screening.

Methods

The West Midlands CF NBS outcomes from 1 November 2006 to 31 October 2021 were reviewed. Clinical data were also obtained for babies referred to the CF centres as ‘CF suspected’.

Results

1 075 161 babies were screened, with 402 referred as ‘CF suspected’ and 205 identified as CF carriers. Of the ‘CF suspected’ babies, 268 were diagnosed with CF, 33 with CF screen positive, inconclusive diagnosis (CFSPID) and 17 as a CF carrier. Any CF-related diagnosis was excluded in 67. Outcome data were not available for 17, of whom 14 had died. Eighteen children with a negative CF NBS have subsequently been diagnosed with CF, 10 had meconium ileus and 8 were true ‘affected not detected’, presenting with respiratory symptoms or failure to thrive. This gives the West Midlands a CF birth prevalence of 1 in 4012 live births and the NBS protocol a sensitivity of 97.1% and a positive predictive value of 66.7%.

Conclusions

This large regional data set has excellent case ascertainment and demonstrates successful performance of the CF NBS protocol, with low numbers identified as CFSPID or CF carriers.
Assessing the performance of ChatGPT in bioethics: a large language model’s moral compass in medicine
Authors: Chen Jamie , Cadiente Angelo , Kasselman Lora J , Pilkington Bryan
Published: November 2023

Chat Generative Pre-Trained Transformer (ChatGPT) has been a growing point of interest in medical education yet has not been assessed in the field of bioethics. This study evaluated the accuracy of ChatGPT-3.5 (April 2023 version) in answering text-based, multiple choice bioethics questions at the level of US third-year and fourth-year medical students. A total of 114 bioethical questions were identified from the widely utilised question banks UWorld and AMBOSS. Accuracy, bioethical categories, difficulty levels, specialty data, error analysis and character count were analysed. We found that ChatGPT had an accuracy of 59.6%, with greater accuracy in topics surrounding death and patient–physician relationships and performed poorly on questions pertaining to informed consent. Of all the specialties, it performed best in paediatrics. Yet, certain specialties and bioethical categories were under-represented. Among the errors made, it tended towards content errors and application errors. There were no significant associations between character count and accuracy. Nevertheless, this investigation contributes to the ongoing dialogue on artificial intelligence’s (AI) role in healthcare and medical education, advocating for further research to fully understand AI systems’ capabilities and constraints in the nuanced field of medical bioethics.
Intrathecal cervical analgesia for cancer pain: a 12-year follow-up study in a comprehensive cancer center
Authors: Dupoiron Denis , Bienfait Florent , Carvajal Gabriel , Seegers Valerie , Douillard Thomas , Jubier-Hamon Sabrina , Delorme Thierry , Julienne Arthur , Pluchon Yves Marie , Ribault Nicolas , Nader Edmond , Lebrec Nathalie
Published: November 2023

Background

Intrathecal analgesia plays a key role for patients suffering refractory cancer pain. Nevertheless, intrathecal drug delivery systems (IDDS), requiring a cervical catheter tip implantation, have been poorly described in medical literature.

Aims

A monocentric retrospective follow-up study was designed to evaluate results of cervical IDDS for cancer pain.

Patients and methods

From January 2010 to December 2022, all intrathecal-treated patients were prescribed a combined intrathecal analgesics regimen through a catheter placed in the cervical vertebral canal. Post-implant assessment of pain was determined using a numeric rating scale (NRS). Patients were followed via day-hospital visits and telephone calls at least monthly. Pain scores were compared using the Wilcoxon’s signed rank test.

Results

Ninety-eight patients were included in this study; all received intrathecal treatments. Implanted patients suffered from severe pain (mean presurgical maximum numerical rating score 8.02±0.24 despite a mean 562.56±127.72 mg of oral morphine equivalent daily dose). Mean survival time after intrathecal treatment start was 208.48±67 days. Intrathecal drug delivery systems provided pain relief compared with initial pain score with a significant statistical difference after 1 week, 1 month, 2 and 3 months (p<0.01). A 50% reduction in initial pain level was achieved in 93% of cases during the first week of intrathecal implant.

Conclusions

Results suggest that long-term intrathecal treatment using a multidrug regimen for cancer-related pain through cervical intrathecal catheters was suitable and safe in our study population. We demonstrated a clinically and statistically significant pain reduction in patients using mainly a percutaneous lumbar approach.
Thermodynamics of deformed AdS-Schwarzschild black hole
Authors: Khosravipoor Mohammad Reza , Farhoudi Mehrdad
Published: November 2023

By implementing the gravitational decoupling method, we find the deformed AdS-Schwarzschild black hole solution when there is also an additional gravitational source, which obeys the weak energy condition. We also deliberately choose its energy density to be a certain monotonic function consistent with the constraints. In the method, there is a positive parameter that can adjust the strength of the effects of the geometric deformations on the background geometry, which we refer to as a deformation parameter. The condition of having an event horizon limits the value of the deformation parameter to an upper bound. After deriving various thermodynamic quantities as a function of the event horizon radius, we mostly focus on the effects of the deformation parameter on the horizon structure, the thermodynamics of the solution and the temperature of the Hawking–Page phase transition. The results show that with the increase of the deformation parameter: the minimum horizon radius required for a black hole to have local thermodynamic equilibrium and the minimum temperature below which there is no black hole decrease, and the horizon radius of the phase transition and the temperature of the first-order Hawking–Page phase transition increase. Furthermore, when the deformation parameter vanishes, the obtained thermodynamic behavior of the black hole is consistent with that stated in the literature.
A regular black hole as the final state of evolution of a singular black hole
Authors: Hu Han-Wen , Lan Chen , Miao Yan-Gang
Published: November 2023

We propose a novel black hole model in which singular and regular black holes are combined as a whole and more precisely singular and regular black holes are regarded as different states of parameter evolution. We refer to them as singular and regular states, respectively. Furthermore, the regular state is depicted by the final state of parameter evolution in the model. We also present the sources that can generate such a black hole spacetime in the framework of F(R) gravity. This theory of modified gravity is adopted because it offers a possible resolution to a tough issue in the thermodynamics of regular black holes, namely the discrepancy between the thermal entropy and Wald entropy. The dynamics and thermodynamics of the novel black hole model are also discussed when a singular state evolves into a regular state during the change of charge or horizon radius from its initial value to its extreme value.
Minimal length scale correction in the noise of gravitons
Authors: Sen Soham , Gangopadhyay Sunandan
Published: November 2023

In this paper we have considered a quantized and linearly polarized gravitational wave interacting with a gravitational wave detector (interferometer detector) in the generalized uncertainty principle (GUP) framework. Following the analysis in Phys. Rev. Lett. 127:081602 (2021), we consider a quantized gravitational wave interacting with a gravitational wave detector (LIGO/VIRGO etc.) using a path integral approach. Although the incoming gravitational wave was quantized, no Planck-scale quantization effects were considered for the detector in earlier literatures. In our work, we consider a modified Heisenberg uncertainty relation with a quadratic order correction in the momentum variable between the two phase space coordinates of the detector. Using a path integral approach, we have obtained a stochastic equation involving the separation between two point-like objects. It is observed that random fluctuations (noises) and the correction terms due to the generalized uncertainty relation plays a crucial role in dictating such trajectories. Finally, we observe that the solution to the stochastic equation leads to time dependent standard deviation due to the GUP insertion, and for a primordial gravitational wave (where the initial state is a squeezed state) both the noise effect and the GUP effects exponentially enhance which may be possible to detect in future generation of gravitational wave detectors. We have also given a plot of the dimensionless standard deviation with time depicting that the GUP effect will carry a distinct signature which may be detectable in the future space based gravitational wave observatories.
Gravitational lensing effects of black hole with conformally coupled scalar hair
Authors: Qi Qi , Meng Yuan , Wang Xi-Jing , Kuang Xiao-Mei
Published: November 2023

In this paper, we investigate the gravitational lensing effects in the weak and strong field limits of a static black hole with conformally coupled scalar field. In the weak field limit, with the use of Gauss–Bonnet theorem we calculate the deflection angle of the light. It is found that comparing to Schwarzschild and Reissner–Nordstr$$\ddot{\text {o}}$$

o
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m (RN) black holes in general relativity, the weak deflection angle can be enhanced/suppressed by the scalar hair. In the strong field limit, we first compute the light deflection angle via calculating the lensing coefficients, all of which increase as the values of electric and scalar charges increase. Then we evaluate the lensing observables in strong field regime by supposing the hairy black hole as the candidate of M87* and SgrA* supermassive black holes, respectively. We find that the scalar hair has significant influences on various observables. In particular, the lensing observables of the charged black hole with positive scalar hair and RN black hole have degeneracy, which will be broken by the case with negative scalar hair. Our theoretical findings imply that it is feasible to employ the gravitational lensing effects as a probe of Einstein–Maxwell theory with negative scalar field differentiating from general relativity, once the future astrophysical observation is precise enough.
A Novel Artificial Social Cognitive Agent Model for Teaching the Concepts
Authors: Gupta Yogesh , Prajapati Atul Prakash
Published: November 2023

Nowadays, extracting the most suitable information becomes a very challenging problem as accumulation of data over Internet is exponentially increasing. This raises the need of such systems which can process data meaningfully, have capability of understanding the user’s questions, and can provide the most relevant information. The existing systems are not capable of giving precise results. The performance of such systems can be improved using Natural Language Processing (NLP) and Cognitive Computing System. Therefore, an artificial cognitive agent is proposed in this paper using NLP, which can take decisions in real-life using social cognition. These agents are expert in their respective domains. Moreover, social behavioural aspects and the constraints of proposed cognitive agent are also modelled in this work. The performance of the proposed agent is evaluated on the concepts of Electric Motor domain in terms of various parameters. The results depict that the proposed artificial cognitive agent obtains satisfactory results.
Integrating Production Scheduling and Vehicle Routing Decisions at the Operational Decision Level: A Review and Discussion Extension
Authors: Elsaeed Ashraf , Ashour Mostafa , Elshaer Raafat
Published: November 2023

As a method of reducing costs and enhancing service quality, companies integrate production and distribution scheduling to improve performance. Thirty-two articles published between 2017 and 2022 are classified based on a review methodology as a continuation of a literature review of the integrated production and distribution scheduling problems at the operational level that was published in 2016. The characteristics of mathematical models and the solution algorithms used are discussed in order to identify gaps and determine future research directions. Through the review, it was found that some real-life characteristics still need further study. Future research may need to consider uncertainty, stochastic elements and evaluating different heuristics and metaheuristics in different production environments. Finally, additional research is necessary to determine under what conditions integration is most effective.
Well and ill-posedness of free boundary problems to relativistic Euler equations
Authors: Geng Yongcai
Published: November 2023

In this paper, via the regularity of sonic speed, we are concerned with the well and ill-posedness problems of the relativistic Euler equations with free boundary. First, we deduce the physical vacuum condition of relativistic Euler equations, which means that the sonic speed [Formula: see text] behaves like a half power of distance to the vacuum boundary [Formula: see text], satisfying [Formula: see text], it belongs to H[Formula: see text]lder continuous. Then, for [Formula: see text], this case means that the sonic speed belongs to [Formula: see text] smooth across the vacuum boundary, it is proved from both Lagrangian and Eulerian coordinates points of view. Finally, for the cases [Formula: see text] and [Formula: see text], the boundary behaviors are verified ill-posed by the unbounded acceleration of the fluid near the vacuum boundary. In this paper, the uniform bounds of velocity [Formula: see text] with respect to [Formula: see text] and the upper bounds for the square of sonic speed [Formula: see text] are very important in the proof of no matter whether well or ill-posedness because this will enable us to avoid many difficulties in the mathematical structure of relativistic fluids especially near the vacuum boundary. It is our innovation that distinguishes from non-relativistic Euler equations [J. Jang and N. Masmoudi, Well and ill-posedness for compressible Euler equations with vacuum, J. Math. Phys. 53 (2012) 1–11].
A two-component nonlinear variational wave system
Authors: Aursand Peder , Nordli Anders
Published: November 2023

We derive a novel two-component generalization of the nonlinear variational wave equation as a model for the director field of a nematic liquid crystal with a variable order parameter. The equation admits classical solutions locally in time. We prove that a special semilinear case is globally well-posed. We show that a particular long time asymptotic expansion around a constant state in a moving frame satisfies the two-component Hunter–Saxton system.
On the chemical characteristics of fullerenes as modelled by R index
Authors: Aldemir Mehmet Şerif , Ediz Süleyman
Published: November 2023

A fundamental allotrope of carbon that has drawn significant interest in the fields of nanoscience, nanotechnology, condensed matter physics and chemistry, biological physics, materials science and technology, mechanical and electrical sciences, biomedical engineering, and most recently, medical nanotechnology, and nanoneuroscience. Fullerenes are another important allotrope of carbon in addition to graphite, diamond, and nanotubes. The use of molecular topological indices is crucial for bridging the gap between theoretical and practical aspects of chemical characteristics. In recent years, topological indices have been used to investigate the chemical and physical characteristics of fullerenes. This paper uses the [Formula: see text] molecular topological index to present topological modeling of the binding energies, heats of formation, shape resonances, and Ramsauer-Townsend minima of fullerenes.