bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification and characterization of the functional tetrameric UDP-glucose pyrophosphorylase from
Klebsiella pneumoniae
Authors: Ramón Roth Isabel , Kats Pavel , Fiebig Timm , Routier Françoise , Fedorov Roman , Dirr Larissa , Führing Jana I.
Published: December 2024

In all kingdoms of life, the enzyme uridine diphosphate-glucose pyrophosphorylase (UGP) occupies a central role in metabolism, as its reaction product uridine diphosphate-glucose (UDP-Glc) is involved in various crucial cellular processes. Pathogens, including fungi, parasites, and bacteria, depend on UGP for the synthesis of virulence factors; in particular, various bacterial species utilize UDP-Glc and its derivatives for the synthesis of lipopolysaccharides, capsular polysaccharides, and biofilm exopolysaccharides. UGPs have, therefore, gained attention as anti-bacterial drug target candidates, prompting us to study their structure-function relationships to provide a basis for the rational development of specific inhibitors. UGP function is tied to its oligomeric state, and the majority of bacterial homologs have been described as tetramers encoded by the
galU
gene. Uniquely, enterobacterial species harbor a second gene,
galF
, encoding a protein with high homology to UGP, whose function is somewhat controversial. Here, we show that the
galF
gene of the opportunistic pathogen
Klebsiella pneumoniae
encodes a dimeric protein that has lost UGP activity, likely due to a combination of active site mutations and an inability to tetramerize, whereas the functional
K. pneumoniae
UGP, encoded by
galU
, is an active tetramer. Our AlphaFold-assisted structure-function relationship studies underline that tetramerization is essential for bacterial UGP function and is facilitated by a common mechanism utilizing conserved key residues. Targeting the respective molecular interfaces, which are absent in human UGP, could provide a means of selectively inhibiting the bacterial virulence factor UGP and potentially rendering pathogenic species avirulent.

IMPORTANCE

The enzyme uridine diphosphate-glucose pyrophosphorylase (UGP) is important for the virulence of bacterial pathogens and, therefore, a potential drug target. In this study, we identify the gene encoding the functional UGP in
Klebsiella pneumoniae
, a bacterium notoriously causing severe antibiotic-resistant infections in humans, and reveal structural and functional features that may aid in the development of new antibiotics.
Temperate phage-antibiotic synergy is widespread—extending to
Pseudomonas
—but varies by phage, host strain, and antibiotic pairing
Authors: Fatima Rabia , Hynes Alexander P.
Published: December 2024

Bacteriophages (phages) are bacterial-specific viruses that can be used alone or with antibiotics to reduce bacterial load. Most phages are unsuitable for therapy because they are “temperate” and can integrate into the host genome, forming a lysogen that is protected from subsequent phage infections. However, integrated phages can be awakened by stressors such as antibiotics. Supported by this interaction, here we explore the potential use of combined temperate phage and antibiotic against the multi-drug-resistant pathogen,
Pseudomonas aeruginosa
. In all, thirty-nine temperate phages were isolated from clinical strains, and a subset was screened for synergy with six antibiotics (ciprofloxacin, levofloxacin, meropenem, piperacillin, tobramycin, and polymyxin B), using checkerboard assays. Interestingly, our screen identified phages that can synergize with each antibiotic, despite their widely differing targets; however, these are highly phage-antibiotic and phage-host pairing specific. Screening across multiple clinical strains reveals that temperate phages can reduce the antibiotic minimum inhibitory concentration up to 32-fold, even in a resistant isolate, functionally re-sensitizing the bacterium to the antibiotic. Meropenem and tobramycin did not reduce the frequency of lysogens, suggesting a mechanism of action independent of the temperate nature of the phages. By contrast, ciprofloxacin and piperacillin were able to reduce the frequency of lysogeny, the former by inducing phages—as previously reported in
E. coli
. Curiously, synergy with piperacillin reduced lysogen survivors, but not by inducing the phages, suggesting an alternative mechanism for biasing the phage lysis-lysogeny equilibrium. Overall, our findings indicate that temperate phages can act as adjuvants in clinically relevant pathogens, even in the presence of antibiotic resistance, thereby drastically expanding their therapeutic potential.

IMPORTANCE

The recent discovery that otherwise therapeutically unusable temperate phages can potentiate the activity of antibiotics, resulting in a potent synergy, has only been tested in
E. coli
, and with a single model phage. Here, working with clinical isolates of
Pseudomonas
and phages from these isolates, we highlight the broad applicability of this synergy—across a variety of mechanisms but also highlight the limitations of predicting the phage, host, and antibiotic combinations that will synergize.
Genome characterization of a simian foamy virus from a human bitten by an African green monkey
Authors: Shankar Anupama , Smith James M. , Switzer William M.
Published: December 2024

We obtained the near-complete simian foamy virus (SFV) genome from an infected human bitten by an African green monkey (
Chlorocebus aethiops;
SFVcae_hu501). The genome is 13,062 nucleotides long with the classical SFV genome structure. Phylogenetically, SFVcae_hu501 clustered closely with SFV from
Ch. aethiops
(SFVagm_LK3).
When HSFs bring the heat—mapping the transcriptional circuitries of HSF-type regulators in
Candida albicans
Authors: Znaidi Sadri
Published: December 2024

Heat shock factor (HSF)-type regulators are stress-responsive transcription factors widely distributed among eukaryotes, including fungi. They carry a four-stranded winged helix-turn-helix DNA-binding domain considered as the signature domain for HSFs. The genome of the opportunistic yeast
Candida albicans
encodes four HSF members, namely, Sfl1, Sfl2, Skn7, and the essential regulator, Hsf1.
C. albicans
HSFs do not only respond to heat shock and/or temperature variation but also to CO
2
levels, oxidative stress, and quorum sensing, acting this way as central decision makers. In this minireview, I follow on the heels of my mSphere of Influence commentary (2020) to provide an overview of the repertoire of HSF regulators in
Saccharomyces cerevisiae
and
C. albicans
and describe how their genetic perturbation in
C. albicans
, coupled with genome-wide expression and location analyses, allow to map their transcriptional circuitry. I highlight how they can regulate, in common, a crucial developmental program: filamentous growth.
Perforin-2 is dispensable for host defense against
Aspergillus fumigatus
and
Candida albicans
Authors: Aufiero Mariano A. , Hung Li-Yin , Herbert De'Broski R. , Hohl Tobias M.
Published: December 2024

Myeloid phagocytes are essential for antifungal immunity against pulmonary
Aspergillus fumigatus
and systemic
Candida albicans
infections. However, the molecular mechanisms underlying fungal clearance by phagocytes remain incompletely understood. In this study, we investigated the role of Perforin-2 (
Mpeg1
) in antifungal immunity. We found that
Mpeg1
−/−
mice generated on a mixed C57BL/6J-DBA/2 background exhibited enhanced survival, reduced lung fungal burden, and greater neutrophil fungal killing activity compared to wild-type C57BL/6J (B6) mice, suggesting that Perforin-2 may impair antifungal immune responses. However, when we compared
Mpeg1
−/−
mice with co-housed
Mpeg
+/+
littermate controls, these differences were no longer observed, indicating that initial findings were likely influenced by differences in the murine genetic background or the microbiota composition. Furthermore, Perforin-2 was dispensable for antifungal immunity during
C. albicans
bloodstream infection. These results suggest that Perforin-2 is not essential for host defense against fungal infections in otherwise immune-competent mice.

IMPORTANCE

Humans encounter fungal pathogens daily and rely on innate immune cells to clear
Aspergillus fumigatus
, the leading cause of mold pneumonia worldwide, and
Candida albicans
, the most common cause of fungal bloodstream infections. The World Health Organization has classified
A. fumigatus
and
C. albicans
as critical priority fungal pathogens due to the emergence of drug resistance and the increasing number of susceptible individuals across the globe. The mechanisms by which innate immune cells clear these fungal pathogens remain incompletely defined. In this study, we examined the role of a pore-forming protein called Perforin-2 in host defense against these fungal pathogens, in part because Perforin-2 has been implicated in antibacterial host defense. Our findings reveal that Perforin-2 is dispensable for antifungal immunity against respiratory
A. fumigatus
and systemic
C. albicans
infections in mice, suggesting that the antimicrobial activity of Perforin-2 does not extend to these two fungal pathogens.
Bisphenol S impairs oocyte quality by inducing gut microbiota dysbiosis
Authors: Zhang Jiaming , Yu Xiaoxia , Li Weidong , Jiang Yunjing , Zhang Liangran , Wang Shunxin
Published: December 2024

A good quality egg is essential for a successful pregnancy and early embryo development. Oocyte development is vulnerable to environmental exposures. Bisphenol S (BPS) is widely used as a replacement for its analog bisphenol A, but the reproductive toxicity of BPS has been of great concern. In this study, we showed that BPS exposure induces dysbiosis of the gut microbiota, which further leads to intestinal permeability and inflammation, and ultimately impairs oocyte quality. More importantly, we found that alginate oligosaccharide reshapes the gut microbiota to improve gut homeostasis, thereby preventing the deleterious effects of BPS on the gut and oocytes. Overall, this study not only demonstrates that BPS exposure impairs the intestine and oocytes by inducing dysbiosis of the gut microbiota but also develops a preventive strategy.

IMPORTANCE

Oocyte development is vulnerable to stimulation by intrinsic and extrinsic factors, particularly many environmental pollutants and chemicals in daily life. The reproductive toxicity of bisphenol S has been of great concern, although it is widely used as a safe substitute for its analog bisphenol A. However, it is not known how bisphenol S impairs oocyte quality. This work presents the exciting finding that bisphenol S induces gut microbiota dysbiosis, which further leads to increased intestinal permeability and inflammation and ultimately damages oocytes. More importantly, we show that alginate oligosaccharide improves gut homeostasis by reshaping the gut microbiota, therefore preventing the bisphenol S-induced gut microbiota dysbiosis and gut and oocyte damage. These findings present a major advance in the understanding of bisphenol S toxicity to oocytes and also provide a preventive strategy.
Geology and genesis of the world-class wollastonite deposit at Shizhushan in South China and implications for exploration
Authors: Yang Yanshen , Yang Zhiming , Pan Xiaofei , Li Xin , Hou Zengqian , Liu Baoshun
Published: December 2024

Wollastonite is an important calc-silicate mineral that has been widely used in industrial manufacturing. However, massive accumulations of wollastonite are not common in nature. In this study, we investigated the geology and genesis of the world’s largest wollastonite deposit (69.55 million tonnes [Mt] of wollastonite) at Shizhushan in the Mengshan district, South China. The wollastonite orebodies in the Shizhushan deposit are hosted by chert-bearing limestones within the Permian Makou Formation formed during the contact metamorphic stage, which is largely dependent on the distance between the Late Triassic magma and strata. Garnet and calcite veinlets, which crosscut the wollastonite orebodies, yielded well-constrained U-Pb ages of 225.3 ± 2.4 Ma (mean square weighted deviation [MSWD] = 0.9; n = 51) and 224.9 ± 2.6 Ma (MSWD = 1.1; n = 45), respectively. These determined ages are coeval with previously published ages of the medium-grained porphyritic biotite granite and fine-grained porphyritic granite (ca. 226 Ma), implying that the emplacement of Late Triassic granites into the chert-bearing limestone led to the formation of the Shizhushan wollastonite deposit. We compiled geological features of wollastonite deposits worldwide and used thermodynamic and thermal diffusion modeling to constrain the key factors controlling the formation of giant wollastonite deposits. These compiled geological features, as well as our thermodynamic and thermal diffusion modeling results collectively unveil that (1) chert-bearing limestone or interbedding of limestone and siliceous rocks (i.e., with minimal dolomite content), (2) enough fluid infiltration, and (3) a sufficient supply of thermal energy from deep-seated plutons (2−4 kbar), are three critical factors controlling the formation of giant wollastonite deposits.
Ordovician backarc setting in the Tongbai orogen, central China: Geochronological and geochemical constraints from the Erlangping metabasites
Authors: Zhang Feifei , Cawood Peter A. , Dong Yunpeng , Wang Mingxia , Yue Yuangang , Han Wei , Gao Hongsen , Xin Chenghui
Published: December 2024

Uncertainty as to the tectonic setting of the Erlangping Group in the Tongbai orogen of central China has hindered reconstruction of the early Paleozoic arc-trench system, and limited the associated understanding of the evolution of the northern branch of the Proto-Tethys Ocean. We present new petrologic, geochronological, elemental, and Sr-Nd-Pb-Hf isotopic data for the Erlangping metabasites from the Tongbai orogen. The results indicate that the Erlangping metabasites formed between 478 Ma and 460 Ma. They are tholeiitic in composition with SiO2 = 47.44−57.31 wt%, Al2O3 = 14.15−19.71 wt%, and MgO = 3.44−11.03 wt%, geochemically subdivided into mid-ocean-ridge basalt (MORB)−like metabasites and high-MgO (>6.0 wt%) and low-MgO (<6.0 wt%) arc-like metabasites. High-MgO arc-like metabasites have lower TiO2, FeOt, Al2O3, Nb/La (mostly <0.20), and εNd(t) values (−0.9 to +3.2) relative to those of low-MgO arc-like rocks. However, low-MgO and high-MgO arc-like rocks have similar positive zircon in situ εHf values and whole-rock Pb isotopic compositions (with 206Pb/204Pb = 17.19−18.74, 207Pb/204Pb = 15.52−15.77, and 208Pb/204Pb = 36.51−38.89), suggestive of the input of recycled sediment-derived components in the depleted mantle. In comparison with the arc-like metabasites, the MORB-like metabasites have higher εNd(t) values (+5.5 to +7.4), and originated from a depleted mantle source newly modified by slab-released fluid. The synthesis of all available data has suggested that the Erlangping Group in the Tongbai orogen developed in a continental backarc basin setting. The Qinling-Tongbai orogen was formed through the northward subduction of the Shangdan Ocean during the Late Ordovician to Early Silurian and is a part of the Proto-Tethys northern branch.
Reattachment of a posteriorly dislocated graft in Descemet’s stripping automated endothelial keratoplasty
Authors: Tarini Shilpa , Panchal Bhavik
Published: December 2024

A man in his early 70s underwent Descemet’s stripping automated endothelial keratoplasty (DSAEK) for endothelial decompensation. During surgery, the DSAEK lenticule dislocated into the vitreous cavity due to the patient’s aphakia and aniridia from a complex cataract operation. After 26 hours, the graft was retrieved, a scleral fixated intraocular lens was implanted and the same dislocated donor lenticule was reattached. Identifying graft orientation was aided by lenticule curvature, Descemet’s membrane folds, stromal striations and gentian violet markings. A 6-month follow-up revealed functional endothelial cells and improved visual acuity. This case elaborates a technique to retrieve a posteriorly dislocated lenticule ensuring minimal damage to the endothelium, details tips for identifying the correct orientation of the lenticule after retrieval and describes graft survival chances after reattachment of the same dislocated lenticule.
Diagnosis and management dilemma in leiomyoma of the anterior vaginal wall
Authors: Kode Prathyusha , Maurya Dilip Kumar , Radhakrishnan Sujithra Devi , Keepanasseril Anish
Published: December 2024

Vaginal leiomyomas, rare benign tumours arising from the vaginal wall, present a diagnostic challenge due to their varied clinical manifestations. We report the case of a woman in her mid-40s who sought medical attention for heavy menstrual bleeding and abdominal pain. Initial examinations revealed a palpable mass within the vaginal canal, prompting further investigation with imaging modalities that confirmed a solid lesion suggestive of leiomyoma. A Tru-Cut biopsy was performed to rule out malignancy, after which surgical excision was carried out. Subsequent histopathological analysis confirmed the diagnosis. The case underscores the importance of considering leiomyomas in the differential diagnosis of vaginal masses and highlights the successful management through appropriate surgical strategies with excellent postoperative outcomes.
Kimura’s disease: a mysterious orbital mass
Authors: Yadav Niraj Kumar , Mishra Nibha , Mehrotra Bandana , Kaur Apjit
Published: December 2024

A male patient in his 20s presented with right lower eyelid swelling and occasional eye ache that was first noticed 3 years ago. Ocular examination revealed a palpable orbital mass, proptosis and restriction of right eye movement. The best-corrected visual acuity in the right eye was 6/24. Fundus examination revealed optic disc hyperemia with a blurred disc margin. Rest ocular examination of both eyes was within normal limits. Haematological examination revealed raised TLC, ESR and eosinophilia. MRI showed a relatively well-defined isointense to hypointense lesion showing heterogeneously post-contrast enhancement involving the belly of the inferior rectus muscle of the right eye. FNAC and histopathology confirmed a diagnosis of Kimura’s disease. Oral leflunomide 10 mg/day and prednisolone 40 mg was advised. The swelling started to decrease within 2 weeks of treatment. At 2 months follow-up, the swelling and mass resolved completely and the patient was asymptomatic.
Plasmablastic myeloma with a history of diffuse large B-cell lymphoma
Authors: Lee Rachel Sooyon , Lohano Sunaina , Safdar Muhammad
Published: December 2024

Plasmablastic myeloma is a rare subtype of multiple myeloma, accounting for 5–10% of all cases, associated with poorer survival rates than typical multiple myeloma. This case report presents a man with plasmablastic myeloma with a previous history of diffuse large B-cell lymphoma which was in remission. He presented with paraplegia due to spinal cord compression and severe weakness. Investigations revealed abnormal immunoglobulin levels, hypercalcaemia and 80–90% bone marrow infiltration by plasmablasts. MRI revealed multiple spinal metastases and an incidental 6.1 cm abdominal aortic aneurysm. Treatment given involved radiotherapy, three rounds of chemotherapy and physiotherapy. The patient showed improvement after radiotherapy, though some spinal lesions still remained. Key challenges included differentiating plasmablastic myeloma from plasmablastic lymphoma due to the history of diffuse large B-cell lymphoma as well as balancing treatment risks from concurrent health issues.
Dexterity assessment of hospital workers: prospective comparative study
Authors: Joseph Tobin , Brown Oliver I , Khalid Sara , Giannoudi Marilena , Sagar Rebecca C , Bunola-Hadfield Elena , Chapman Stephen J , A Slater Thomas , Straw Sam , Drozd Michael
Published: December 2024

Objectives

To compare the manual dexterity and composure under pressure of people in different hospital staff roles using a buzz wire game.

Design

Prospective, observational, comparative study (Tremor study).

Setting

Leeds Teaching Hospitals NHS Trust, Leeds, UK, during a three week period in 2024.

Participants

254 hospital staff members comprising of 60 physicians, 64 surgeons, 69 nurses, and 61 non-clinical staff.

Main outcome measures

Successful completion of the buzz wire game within five minutes and occurrence of swearing and audible noises of frustration.

Results

Of the 254 hospital staff that participated, surgeons had significantly higher success rates in completing the buzz wire game within five minutes (84%, n=54) compared with physicians (57%, n=34), nurses (54%, n=37), and non-clinical staff (51%, n=31) (P<0.001). Time-to-event analysis showed that surgeons were quicker to successfully complete the game, independent of age and gender. Surgeons exhibited the highest rate of swearing during the game (50%, n=32), followed by nurses (30%, n=21), physicians (25%, n=60), and non-clinical staff (23%, n=14) (P=0.004). Non-clinical staff showed the highest use of frustration noises (75%), followed by nurses (68%), surgeons (58%), and physicians (52%) (P=0.03).

Conclusions

Surgeons showed greater dexterity, but higher levels of swearing compared with other hospital staff roles, while nurses and non-clinical staff showed the highest rates of audible noises of frustration. The study highlights the diverse skill sets across hospital staff roles. Implementation of a surgical swear jar initiative should be considered for future fundraising events.
The evolution of grouting pressure and ground deformation induced by synchronous grouting during shield tunneling in soft soil: an investigation based on scaled model test and CEL simulation
Authors: Liu Fengzhou , Chen Wei , Liu Chao , Yang Yubing , Wang Jing , Liu Yi
Published: December 2024

Synchronous grouting is critical for controlling ground deformation during the shield tunneling process in soft soil. The grout filling and spreading mechanism inside the tail-void remains unclear, primarily due to the challenges of observing grout behavior behind the lining in practice and replicating its movement in numerical simulations. This study conducted a scaled model test with a cover–diameter ratio of 1.0, considering varying grouting volume ratios (GVR). A finite element model using the coupled Eulerian–Lagrangian method was established to simulate the grout filling and spreading process. The evolution of ground surface settlement, grouting pressure (GP), vertical displacement, and soil stress around the tunnel were investigated. Results indicated that in soft soil, the grout–mortar initially fills the tail-void before compression. The GPs at the tunnel shoulder and invert were higher than at the crown and waist. Increased GVR caused soil upheaval at the tunnel crown and shoulders and settlement at the invert and spring-line. However, the vertical displacement at the tunnel waist remained unaffected by the variation in GVR. Slight soil stress at the tunnel waist was observed, suggesting a dominant grouting mode of void-filling at the waist.
Tolerance mechanisms and molecular epidemiology of reduced susceptibility to chlorhexidine digluconate in different species of the Acinetobacter baumannii complex
Authors: Chen Liqiong , Liu Shixing , Huang Na , Xu Chunquan , Zhou Cui , Wang Lingbo , Zheng Xiangkuo , Zhou Tieli , Yu Pingting
Published: December 2024

The objective of this study was to compare chlorhexidine digluconate and other antibiotics susceptibility of four species of the Acinetobacter baumannii complex, and further investigate the chlorhexidine digluconate (CHG) tolerance mechanisms and molecular epidemic characteristics. Of 889 A. baumannii complex isolates, A. baumannii, A. nosocomialis, A. pittii, and A. seifertii accounted for 84.2%, 10.9%, 3.4%, and 1.5%. Acinetobacter baumannii was generally resistant to all tested antibiotics, while other three species were commonly more susceptible; 92.1% (313/340) CHG-tolerant A. baumannii, 19.6% (19/97) CHG-tolerant A. nosocomialis, 3.3% (1/30) CHG-tolerant A. pittii, and 15.4% (2/13) CHG-tolerant A. seifertii were identified. Furthermore, compared to A. baumannii ATCC 19606, upregulated expression was found in qacEΔ1, fabI, and efflux pump encoding genes in CHG-tolerant A. baumannii, but the expression level of oprD was reduced. Additionally, only the expression level of fabI was increased in the CHG-tolerant A. nosocomialis, and the expression level of adeG was increased in the CHG-tolerant A. pittii and A. seifertii. Furthermore, CHG-tolerant A. baumannii may have a relatively high clonal correlation, the predominant sequence type of which was ST208 (90%, 36/40). It is rather necessary to identify specific species members among the A. baumannii complex for clinical treatment options and antibiotics resistance monitoring.
Balancing conflicting goals in ungulate management and forestry in the light of climate change in hemiboreal and boreal forests: insights from Europe and Northern America
Authors: Neumann Wiebke , Hjältén Joakim , De Jager Nathan R. , Girona Miguel Montoro , Hof Anouschka R.
Published: December 2024

Forests produce a vast diversity of ecosystem services. To safeguard management goals such as timber production, forest management needs to consider risks for damage caused by different agents, such as ungulates. The selective foraging behaviour of ungulates can limit forest regeneration, generating conflicts with forestry objectives and challenging both forest and ungulate management. In hemiboreal and boreal forests, both timber production and ungulate numbers have increased considerably during the past 50 years. Climate change will affect forestry and ungulates, possibly generating novel ungulate–forest interactions (e.g., changed forest systems, new herbivore assemblages). To support a framework for future management of ungulate–forest systems in hemiboreal and boreal forests in Europe and North America in the light of climate change, we provide an overview of the literature on current management strategies that seek to balance the conflict between timber production and maintaining ungulate densities at a level that satisfies various stakeholder groups. Derived from current literature, we suggest that future mitigations enhancing forest resilience and simultaneously reducing browsing damage should include the following overarching strategies: (1) Both ungulate and forest management require a large-scale and context-specific planning to ensure a suitable forage landscape for ungulates diluting browsing pressure on economic valuable trees. This might be particularly needed in places where much of the forest is privately owned. (2) Anthropogenic ungulate–forest systems require continuous regulation of ungulate numbers (i.e., by predation, hunting, or a combination of both) to enable “windows of opportunities” for forest regeneration and to counteract positive feedback loops of forage-enriching activities for ungulates by forestry. (3) Given increasing system complexity, adaptive ecosystem-based management plans for ungulates should consider multispecies approaches to match management with other interests in multifunctional forest landscapes. Given the large diversity across northern temperate and boreal ungulate–forest systems (e.g., centralized versus de-centralized management, access to land, game meat trade, ecological and social complexity), there are differences in preconditions across the Northern hemisphere to balance timber production and ungulate densities.
Thermodynamical topology with multiple defect curves for dyonic AdS black holes
Authors: Chen Zi-Qing , Wei Shao-Wen
Published: December 2024

Dyonic black holes with quasitopological electromagnetism exhibit an intriguing phase diagram with two separated first-order coexistence curves. In this paper, we aim to uncover its influence on the black hole thermodynamical topology. At first, we investigate the phase transition and phase diagram of the dyonic black holes. Comparing with previous study that there is no black hole phase transition region for a middle pressure, we find this region can narrow or disappear by fine tuning the coupling parameter. Instead, two first-order phase transitions can be observed. Importantly, we uncover that such novel phase diagram shall lead to a multiple defect curve phenomenon in black hole topology where each dyonic black hole is treated as one defect in the thermodynamical parameter space. By examining the topology, it is shown that there could be one, three, or five black hole states for given pressure and temperature. For each case, the topological number is calculated. Our results show that the topological number always takes value of

$$+1$$

+
1

, keeping unchanged even when the multiple defect curves appear. Therefore, our study provides an important ingredient on understanding the black hole thermodynamical topology.
Analyzing the speed of sound in neutron star with machine learning
Authors: Chatterjee Sagnik , Sudhakaran Harsha , Mallick Ritam
Published: December 2024

Matter properties at the intermediate densities are still unknown to us. In this work, we use a neural network approach to study matter at intermediate densities to analyze the variation of the speed of sound and the measure of trace anomaly considering astrophysical constraints of mass–radius measurement of 18 neutron stars. Our numerical results show that there is a sharp rise in the speed of sound just beyond the saturation energy density. It attains a peak around 3–4 times the saturation energy density and, after that, decreases. This hints towards the appearance of new degrees of freedom and smooth transition from hadronic matter in massive stars. The trace anomaly is maximum at low density (surface of the stars) and decreases as we reach high density. It approaches zero and can even be slightly negative at the centre of massive stars. It has a negative trough beyond the maximal central densities of neutron stars. The change in sign of the trace anomaly hints towards a near-conformal matter at the centre of neutron stars, which may not necessarily be conformal quark matter.
Modular data of non-semisimple modular categories
Authors: Chang Liang , Kolt Quinn T. , Wang Zhenghan , Zhang Qing
Published: December 2024

We investigate non-semisimple modular categories with an eye towards a structure theory, low-rank classification and applications to low dimensional topology and topological physics. We aim to extend the well-understood theory of semisimple modular categories to the non-semisimple case by using representations of factorizable ribbon Hopf algebras as a case study. We focus on the Cohen–Westreich modular data, which is obtained from the Lyubashenko–Majid modular representation restricted to the Higman ideal of a factorizable ribbon Hopf algebra. The Cohen–Westreich [Formula: see text]-matrix diagonalizes the mixed fusion rules and reduces to the usual [Formula: see text]-matrix for semisimple modular categories. The paper includes detailed studies on small quantum groups [Formula: see text] and the Drinfeld doubles of Nichols Hopf algebras, especially the [Formula: see text]-representation on their centers, Cohen–Westreich modular data, and the congruence kernel theorem’s validity.
Dark energy from a gas of thin tubes of a massless scalar field
Authors: Lelyakov A. P. , Lelyakov S. A.
Published: December 2024

In this work, we investigated the influence on the evolution of gas of thin tubes of a massless scalar field, in particular, on its ability to accelerated expansion, of such characteristics of thin tubes forming gas as thickness (core radius), the moment of their formation and spatial shape. The study showed that the formation of thin tubes of a scalar field that form gas becomes possible only some time after the singular state of the Universe. At the same time, the thinner the tubes form a gas, and the later in the process of evolution they were formed, the faster such a gas can achieve the equation of state [Formula: see text].
Uniqueness for local–nonlocal elliptic equations
Authors: Biagi Stefano , Meglioli Giulia , Punzo Fabio
Published: December 2024

We study mixed local and nonlocal elliptic equation with a variable coefficient [Formula: see text]. Under suitable assumptions on the behavior at infinity of [Formula: see text], we obtain uniqueness of solutions belonging to certain weighted Lebesgue spaces, with a weight depending on the coefficient [Formula: see text]. The hypothesis on [Formula: see text] is optimal; indeed, when it fails we get nonuniqueness of solutions. We also investigate the parabolic counterpart of such equation.
Analysis of Vibration Suppression Effect of Parallel Combined Damping NES System on Nonsmooth System
Authors: Qi Xingke , Zhang Jianchao , Wang Jun
Published: December 2024

In this paper, the dynamics modeling and vibration suppression analysis of a nonsmooth system with coupled parallel combined damping NES system is carried out. First, the mechanical and mathematical models of the system are established, and the functional expressions of the nonsmooth terms are given. Second, the damping effect of the parallel combined damping NES under impulsive excitation is analyzed, and the damping effect of the parallel connection under different excitation intensities is analyzed by using the comparison of time response and energy change, as well as the influence of the NES parameters on the vibration suppression situation of the system. Finally, the vibration-damping effect exerted by the parallel combined damping NES under random excitation is analyzed, and the influence of the NES parameters is analyzed on the basis of the probability densities of displacement and energy. The results of the study show that the parallel connection provides better damping performance than a single connection, both under impulsive excitation and under random excitation, and that the optimal value of the system mass ratio is not 0.1 under this connection; it is also found that, under both forms of excitation, the parameter values of the NES are not taken to be larger, the better the damping effect suffered by the main system, but that there exists an appropriate range of values. This study is an important theoretical guide for the engineering application of multi-degree-of-freedom NES.
Experimental and Simulation Studies on Deflection-to-Span Ratio Limit of the 25m Simply-Supported Girder for Urban Maglev Transit
Authors: Peng Yeye , Gong Junhu , Zhao Chunfa , Feng Yang , Li Weiqiang , He Feng
Published: December 2024

Four commercial urban maglev lines have already been put into operation, demonstrating the safety, comfort, environmental sustainability, and low maintenance of this innovative rail transit system. To further promote and apply this technology, reducing line construction costs has now become a priority. The deflection-to-span ratio limit of the girder plays a significant role in determining the construction cost of commercial lines. According to Chinese standards, the vertical deflection-to-span ratio limit for simply supported girders under maglev train loads is set at 1/3800 to prevent strong coupling vibrations between the maglev train and the girder, which could lead to levitation failure (i.e. the collision between the electromagnet and the rail). However, the current deflection-to-span ratio used in commercial lines is smaller, contributing to the high construction costs of commercial lines. To investigate whether the deflection-to-span ratio can be reduced, a 25[Formula: see text]m span variable-stiffness steel girder was designed and manufactured, with the deflection-to-span ratio range between 1/2000 and 1/4500. A coupled dynamic model of the maglev train-controllable electromagnetic force-variable stiffness girder was then established. Tests were conducted to analyze the dynamic responses of a single-car maglev train traveling over the variable stiffness girder at speeds of 20–60[Formula: see text]km/h, with the results being used to validate the numerical model. The coupled dynamic simulation analysis was also performed for the three-car maglev train traveling at speeds ranging from 20[Formula: see text]km/h to 100[Formula: see text]km/h. By focusing on levitation gap fluctuations and ride quality, the study discussed an optimal deflection-to-span ratio for the 25[Formula: see text]m span girder. Simulation results indicate that, regardless of the deflection-to-span ratio of the girder, the vertical accelerations of both the levitation bogie and the F-shaped rail initially decrease with increasing speed, then gradually increase. However, the vertical accelerations of both the carbody and the girder increase consistently with speed. As the deflection-to-span ratio decreases, the dynamic response of the coupling system gradually decreases. The deflection-to-span ratio of 1/2970 is optimal, ensuring both the safe and smooth operation of the maglev train while significantly reducing construction costs.
Extracting Biomedical Signals from High Noise Environments
Authors: Kuljić Bojan , Odry Peter
Published: December 2024

Modern measurement systems must have the ability to perform measurements in high-level noise environments. The field with a particularly high content of noise is biomedicine. The traditional approach to solving this problem is to inject very high energy signals in order to minimize the impact of noise on the measurement (Magnetic resonance imaging, X-rays). Unfortunately, this means that these systems are very large, expensive, difficult to maintain and often contain toxic materials. This paper presents research aimed at finding a non-invasive method that uses low-intensity signals that are completely harmless to humans, and at the same time allows extracting the measured signal from a highly noised environment. Noise suppression was achieved with a lock-in amplifier.
Strong metric dimension of clean graphs of commutative rings
Authors: Mathil Praveen , Kumar Jitender
Published: December 2024

Let [Formula: see text] be a ring with unity. The clean graph [Formula: see text] of a ring [Formula: see text] is the simple undirected graph whose vertices are of the form [Formula: see text], where [Formula: see text] is an idempotent element and [Formula: see text] is a unit of the ring [Formula: see text], and two vertices [Formula: see text], [Formula: see text] of [Formula: see text] are adjacent if and only if [Formula: see text] or [Formula: see text]. In this paper, for a commutative ring [Formula: see text], first we obtain the strong resolving graph of [Formula: see text] and its independence number. Using them, we determine the strong metric dimension of the clean graph of an arbitrary commutative ring. As an application, we compute the strong metric dimension of [Formula: see text], where [Formula: see text] is a commutative Artinian ring.
ANALYSIS OF RUMOR PROPAGATION DYNAMICS IN COMPLEX NETWORKS
Authors: YAN GUANGHUI , TANG JIE , PEI HUAYAN , CHANG WENWEN
Published: December 2024

Considering that rumors propagation is affected by many factors in real life, based on the SIRS infectious disease model in complex networks, an extended ISRI rumor propagation model is proposed by using the probability function to define the influence mechanisms such as trust mechanism, and suspicion mechanism. First, dynamic equations are established for homogeneous and heterogeneous networks, and the rumor and rumor-free equilibrium points in the two networks are analyzed, respectively. Then, the basic reproduction number [Formula: see text] is obtained by using the next generation matrix and derivative calculation methods. Next, the lyapunov function is constructed to discuss the local stability and global stability of the equilibrium point, and the influence of different parameters on the basic reproduction number [Formula: see text]. In addition, we selected ER network and BA network and found that population flow has a significant impact on the speed and scale of rumor propagation. At the same time, the trust mechanism can improve the propagation speed and scale, while the skepticism mechanism can inhibit the propagation speed, and it is more obvious in the BA network. The interaction between these mechanisms further affects the propagation characteristics of rumors in the network.
On m-clean index of ring
Authors: Das S. , Kar S.
Published: December 2024

A ring [Formula: see text] is called [Formula: see text]-clean if each element of [Formula: see text] can be expressed as the sum of a unit and an [Formula: see text]-potent in [Formula: see text]. We introduce the concept of the [Formula: see text]-clean index associated with a ring [Formula: see text]. For any element [Formula: see text], we define [Formula: see text], where [Formula: see text] denotes the set of units of [Formula: see text]. Then the [Formula: see text]-clean index of the ring [Formula: see text] is defined as [Formula: see text] and it is denoted by [Formula: see text]-[Formula: see text]-[Formula: see text]. In this paper, we study some properties of this index and characterize the ring of [Formula: see text]-clean index [Formula: see text]. We show that the rings with the [Formula: see text]-clean index 1 are precisely the rings whose [Formula: see text]-clean index is [Formula: see text] and each [Formula: see text]-potent is idempotent. We establish some connections between [Formula: see text]-clean index of the ring [Formula: see text] and the underlying rings [Formula: see text] and [Formula: see text]-module [Formula: see text]. We also determine the [Formula: see text]-clean index of the trivial extension [Formula: see text] and the [Formula: see text]-clean index of the ideal extension [Formula: see text] with some associated conditions. Finally, we discuss the amalgamated structure of ring in connection to the [Formula: see text]-clean index.
Vanadium pentoxide-coated smart windows for passive radiative cooling applications
Authors: Uma Sathyakam P. , Gupta Dhruv , Bhaumik Rishabh , Vijayaraghavan R. , Mishra Ajay Kumar
Published: December 2024

Passive radiative cooling (PRC)-based smart windows are emerging as a potential solution for reducing the energy needs of buildings, both homes and offices alike. While a lot of research has occurred in this regard, vanadium oxide-based materials are studied very recently. We carry out a finite element method-based simulation study to understand the behavior of using vanadium pentoxide (V2O5) as a coating on glass windows. The proposed design can help in saving energy by emitting cooler rays inside the building when direct sun rays fall on the coated glass surface, thereby reducing internal room temperatures. It is also a solution to global warming, as the emissions from ACs will reduce due to the lower inside temperature of buildings thereby reducing demand on power usage. We found that the ambient temperature ([Formula: see text]) inside buildings can be reduced by up to [Formula: see text] when the outer temperature is [Formula: see text]. Also, the surface radiosity of V2O5 windows is twice that of glass windows and increases with the outer temperature. Lastly, we compare the performance of V2O5 with that of VO2 and find that they have similar characteristics of radiant exitance, surface radiosity and surface emissivity of long-wave infrared (LWIR) rays thus making V2O5 as a possible candidate for PRC which is low cost and affordable to many people.
Electrospun Ba(Ti0.80 Zr0.20)O3-0.5(Ba0.70Ca0.30)TiO3-CoFe2O4 multiferroic hybrid nanofiber for the localized piezocatalytic degradation of organic pollutants
Authors: Cheng Junfu , Yang Han , Fu Bi , Lu Ruie , Yang Yaodong , Chen Zhanxu , He Yingji , Dai Jianfeng , Wang Yaping
Published: December 2024

Multiferroic Ba(Ti[Formula: see text]Zr[Formula: see text])O3-0.5(Ba[Formula: see text]Ca[Formula: see text])TiO3 (BCTZ)@CoFe2O4 (CFO) hybrid nanofibers (NFs) were fabricated by a sol–gel electrospinning. The perovskite structure of ferroelectric BCTZ and the spinel structure of ferromagnetic CFO coexist and are homogeneously distributed, and their interface along the perovskite [110] zone axis was directly observed. The indirect magnetoelectric (ME) coupling effect was observed from the magnetization versus temperature (M–T) curves, demonstrating a distinct singularity on the dM/dT curve near the ferroelectric Curie temperature ([Formula: see text][Formula: see text]) of 387 K. The piezocatalytic rate of BCTZ@CFO multiferroic hybrid NF (2.6 × 10[Formula: see text]min[Formula: see text]) is higher than NP (1.9 × 10[Formula: see text]min[Formula: see text]) because the piezoelectricity of the one-dimensional (1D) multiferroic NF is higher than that of NPs, beneficial for the mechanical vibration-induced localized built-in electric fields for piezocatalysis under ultrasound.
Path planning and real-time optimization of robotic arm 3D printing
Authors: Wang Yaxin , Zhao Chun , Liu Wenzheng , Li Shun
Published: December 2024

In the era of Industry 4.0, 3D printing has shown significant outcomes. To address the challenges of large-format complex material printing and forming, such as spatial constraints and excessive support structures in traditional 3D printing, the integration of industrial robots with 3D printing technology is proposed. However, robotic 3D printing introduces challenges in path planning and real-time optimization. This paper presents a methodology for path planning and real-time optimization of robotic arms on a 3D printing platform. The approach involves adjusting the printing path by modifying the nozzle printing posture and implementing obstacle avoidance algorithms. The study uses geometric and algebraic methods to optimize the robotic arm trajectory to improve the precision of reaching print points, reduce the printing cycle, and minimize material wastage. To verify the feasibility of this method, a case study in 3D printing is conducted to examine the practical application of motion planning for robotic arms based on digital twin technology.
Heterogeneous Regularization for Fast Rendering Using Deep Spike Neural Network
Authors: Constantin Joseph , Constantin Ibtissam , Dornaika Fadi , Hoang Vinh Truong
Published: December 2024

A Deep Spiking Neural Network (DSNN) with Heterogeneous Regularization learning technique is proposed to build a more biologically plausible approach that evaluates the amount of noise and finds a stopping criterion for fast realistic illumination. Our contribution is to introduce a model that improves the label propagation of DSNN and is more efficient on neuromorphic hardware than a corresponding Artificial Neural Network. More specifically, we develop a biological neural model with a heterogeneous regularization technique that works similarly to a human brain and can detect noise using deep spikes without relying on mathematical metrics to extract noise features. The objective function of the proposed DSNN consists of a supervised term and an unsupervised term. The supervised term enforces the matching term between the predicted labels and the known labels. The unsupervised term enforces the smoothness of the predicted labels of the entire data samples. By learning a DSNN with the proposed objective function, we are able to develop a more powerful learning algorithm. Experiments were conducted using scenes with Global Illumination and various image distortions. The proposed model was also compared with the human visual system and other state-of-the-art models. The results show better performance and advantages in terms of efficiency, an increasingly biologically plausible network, and ease of implementation in Neuromorphic Hardware.