bluuebunny/crossref_metadata_2025 huggingface dataset:
Bilateral widefield calcium imaging reveals circuit asymmetries and lateralized functional activation of the mouse auditory cortex
Authors: Calhoun Georgia , Chen Chih-Ting , Kanold Patrick O.
Published: July 2023

Coordinated functioning of the two cortical hemispheres is crucial for perception. The human auditory cortex (ACx) shows functional lateralization with the left hemisphere specialized for processing speech, whereas the right analyzes spectral content. In mice, virgin females demonstrate a left-hemisphere response bias to pup vocalizations that strengthens with motherhood. However, how this lateralized function is established is unclear. We developed a widefield imaging microscope to simultaneously image both hemispheres of mice to bilaterally monitor functional responses. We found that global ACx topography is symmetrical and stereotyped. In both male and virgin female mice, the secondary auditory cortex (A2) in the left hemisphere shows larger responses than right to high-frequency tones and adult vocalizations; however, only virgin female mice show a left-hemisphere bias in A2 in response to adult pain calls. These results indicate hemispheric bias with both sex-independent and -dependent aspects. Analyzing cross-hemispheric functional correlations showed that asymmetries exist in the strength of correlations between DM-AAF and A2-AAF, while other ACx areas showed smaller differences. We found that A2 showed lower cross-hemisphere correlation than other cortical areas, consistent with the lateralized functional activation of A2. Cross-hemispheric activity correlations are lower in deaf, otoferlin knockout (OTOF
−/−
) mice, indicating that the development of functional cross-hemispheric connections is experience dependent. Together, our results reveal that ACx is topographically symmetric at the macroscopic scale but that higher-order A2 shows sex-dependent and independent lateralized responses due to asymmetric intercortical functional connections. Moreover, our results suggest that sensory experience is required to establish functional cross-hemispheric connectivity.
Geometrical control of interface patterning underlies active matter invasion
Authors: Xu Haoran , Nejad Mehrana R. , Yeomans Julia M. , Wu Yilin
Published: July 2023

Interaction between active materials and the boundaries of geometrical confinement is key to many emergent phenomena in active systems. For living active matter consisting of animal cells or motile bacteria, the confinement boundary is often a deformable interface, and it has been unclear how activity-induced interface dynamics might lead to morphogenesis and pattern formation. Here, we studied the evolution of bacterial active matter confined by a deformable boundary. We found that an ordered morphological pattern emerged at the interface characterized by periodically spaced interfacial protrusions; behind the interfacial protrusions, bacterial swimmers self-organized into multicellular clusters displaying +1/2 nematic defects. Subsequently, a hierarchical sequence of transitions from interfacial protrusions to creeping branches allowed the bacterial active drop to rapidly invade surrounding space with a striking self-similar branch pattern. We found that this interface patterning is geometrically controlled by the local curvature of the interface, a phenomenon we denote as collective curvature sensing. Using a continuum active model, we revealed that the collective curvature sensing arises from enhanced active stresses near high-curvature regions, with the active length scale setting the characteristic distance between the interfacial protrusions. Our findings reveal a protrusion-to-branch transition as a unique mode of active matter invasion and suggest a strategy to engineer pattern formation of active materials.
In vivo versus in silico assessment of potentially pathogenic missense variants in human reproductive genes
Authors: Ding Xinbao , Singh Priti , Schimenti Kerry , Tran Tina N. , Fragoza Robert , Hardy Jimmaline , Orwig Kyle E. , Olszewska Marta , Kurpisz Maciej K. , Yatsenko Alexander N. , Conrad Donald F. , Yu Haiyuan , Schimenti John C.
Published: July 2023

Infertility is a heterogeneous condition, with genetic causes thought to underlie a substantial fraction of cases. Genome sequencing is becoming increasingly important for genetic diagnosis of diseases including idiopathic infertility; however, most rare or minor alleles identified in patients are variants of uncertain significance (VUS). Interpreting the functional impacts of VUS is challenging but profoundly important for clinical management and genetic counseling. To determine the consequences of these variants in key fertility genes, we functionally evaluated 11 missense variants in the genes
ANKRD31, BRDT
,
DMC1, EXO1
,
FKBP6, MCM9
,
M1AP, MEI1, MSH4
and
SEPT12
by generating genome-edited mouse models. Nine variants were classified as deleterious by most functional prediction algorithms, and two disrupted a protein–protein interaction (PPI) in the yeast two hybrid (Y2H) assay. Though these genes are essential for normal meiosis or spermiogenesis in mice, only one variant, observed in the
MCM9
gene of a male infertility patient, compromised fertility or gametogenesis in the mouse models. To explore the disconnect between predictions and outcomes, we compared pathogenicity calls of missense variants made by ten widely used algorithms to 1) those annotated in ClinVar and 2) those evaluated in mice. All the algorithms performed poorly in terms of predicting the effects of human missense variants modeled in mice. These studies emphasize caution in the genetic diagnoses of infertile patients based primarily on pathogenicity prediction algorithms and emphasize the need for alternative and efficient in vitro or in vivo functional validation models for more effective and accurate VUS description to either pathogenic or benign categories.
Intramolecular structural heterogeneity altered by long-range contacts in an intrinsically disordered protein
Authors: Koren Gil , Meir Sagi , Holschuh Lennard , Mertens Haydyn D. T. , Ehm Tamara , Yahalom Nadav , Golombek Adina , Schwartz Tal , Svergun Dmitri I. , Saleh Omar A. , Dzubiella Joachim , Beck Roy
Published: July 2023

Short-range interactions and long-range contacts drive the 3D folding of structured proteins. The proteins’ structure has a direct impact on their biological function. However, nearly 40% of the eukaryotes proteome is composed of intrinsically disordered proteins (IDPs) and protein regions that fluctuate between ensembles of numerous conformations. Therefore, to understand their biological function, it is critical to depict how the structural ensemble statistics correlate to the IDPs’ amino acid sequence. Here, using small-angle X-ray scattering and time-resolved Förster resonance energy transfer (trFRET), we study the intramolecular structural heterogeneity of the neurofilament low intrinsically disordered tail domain (NFLt). Using theoretical results of polymer physics, we find that the Flory scaling exponent of NFLt subsegments correlates linearly with their net charge, ranging from statistics of ideal to self-avoiding chains. Surprisingly, measuring the same segments in the context of the whole NFLt protein, we find that regardless of the peptide sequence, the segments’ structural statistics are more expanded than when measured independently. Our findings show that while polymer physics can, to some level, relate the IDP’s sequence to its ensemble conformations, long-range contacts between distant amino acids play a crucial role in determining intramolecular structures. This emphasizes the necessity of advanced polymer theories to fully describe IDPs ensembles with the hope that it will allow us to model their biological function.
Cytoskeleton remodeling mediated by circRNA-YBX1 phase separation suppresses the metastasis of liver cancer
Authors: Liu Boqiang , Shen Hao , He Jing , Jin Binghan , Tian Yuanshi , Li Weiqi , Hou Lidan , Zhao Weijun , Nan Junjie , Zhao Jia , Shen Jiliang , Yu Hong , Wang Yifan , Shan Ge , Shi Liang , Cai Xiujun
Published: July 2023

Metastasis, especially intrahepatic, is a major challenge for hepatocellular carcinoma (HCC) treatment. Cytoskeleton remodeling has been identified as a vital process mediating intrahepatic spreading. Previously, we reported that HCC tumor adhesion and invasion were modulated by circular RNA (circRNA), which has emerged as an important regulator of various cellular processes and has been implicated in cancer progression. Here, we uncovered a nuclear circRNA, circASH2, which is preferentially lost in HCC tissues and inhibits HCC metastasis by altering tumor cytoskeleton structure. Tropomyosin 4 (TPM4), a critical binding protein of actin, turned out to be the major target of circASH2 and was posttranscriptionally suppressed. Such regulation is based on messenger RNA (mRNA)/precursormRNA splicing and degradation process. Furthermore, liquid–liquid phase separation of nuclear Y-box binding protein 1 (YBX1) enhanced by circASH2 augments TPM4 transcripts decay. Together, our data have revealed a tumor-suppressive circRNA and, more importantly, uncovered a fine regulation mechanism for HCC progression.
Chloramines as an important photochemical source of chlorine atoms in the urban atmosphere
Authors: Wang Chen , Liggio John , Wentzell Jeremy J. B. , Jorga Spiro , Folkerson Andrew , Abbatt Jonathan P. D.
Published: July 2023

Monochloramine, dichloramine and trichloramine (NH
2
Cl, NHCl
2
, NCl
3
) are measured in the ambient atmosphere, in downtown Toronto in summer (median 39, 15 and 2.8 ppt) and winter (median 11, 7.3 and 0.7 ppt). NCl
3
and NHCl
2
were also measured in summer (median 1.3 and 14 ppt) from a suburban Toronto location. Measurements at two locations demonstrate prevalence of chloramines in an urban atmosphere. At both sites, NCl
3
exhibits a strong diel pattern with maximum values during the night, and photolytic loss with sunrise. At the downtown site, a strong positive correlation between NH
2
Cl and NHCl
2
in the summer night indicates a common source, with daily average peak mixing ratios approaching 500 and 250 ppt, respectively. As a previously unidentified source of chlorine (Cl) atoms, we demonstrate that NCl
3
photolysis contributes 49 to 82% of the total local summertime Cl production rate at different times during the day with an average noontime peak of 3.8 × 10
5
atoms/cm
3
/s, with smaller contributions from ClNO
2
and Cl
2
. Photolysis of NH
2
Cl and NHCl
2
may augment this Cl production rate. Our measurements also demonstrate a daytime enhancement of chloroacetone in both the summer and winter, demonstrating the importance of Cl photochemistry. The results suggest that chloramines are an important source of Cl atoms in urban areas, with potential impacts on the abundance of organic compounds, ozone, nitrogen oxides, and particulate matter. Future studies should explore the vertical gradients of chloramines and their contribution to Cl production throughout the boundary layer.
Pelvic shape change in adult Japanese macaques and implications for childbirth at old age
Authors: Morimoto Naoki , Kawada Mikaze , Tomizawa Yuma , Kaneko Akihisa , Nishimura Takeshi
Published: July 2023

Pelvic morphology exhibits a particular sexual dimorphism in humans, which reflects obstetrical constraints due to the tight fit between neonates and mothers. Huseynov et al. [
Proc. Natl. Acad. Sci. U.S.A.
113
, 5227–5232 (2016)] showed that in humans, pelvic sexual dimorphism is greatest around the age of highest fertility, and it becomes less marked in association with menopause in females. They proposed that this reflects changes of obstetrical versus locomotor functional demands in females. It remains unknown whether such developmental adjustment of the pelvic morphology is unique to humans. Macaques exhibit human-like cephalopelvic proportions, but they lack menopause and usually maintain fertility throughout adulthood. Here, we track pelvic development in Japanese macaques from neonate to advanced ages using computed tomography-based data. We show that female pelvic morphology changes throughout adult life, reaching the obstetrically most favorable shape at advanced ages rather than around primiparity. We hypothesize that pelvic morphology in Japanese macaques is developmentally adjusted to childbirth at advanced ages, where obstetrical risks are potentially higher than at younger ages. Our data contribute to the growing evidence that the female primate pelvis changes its morphology during the whole lifespan, possibly adjusting for changing functional demands during adulthood.
Quantum criticality enabled by intertwined degrees of freedom
Authors: Liu Chia-Chuan , Paschen Silke , Si Qimiao
Published: July 2023

Strange metals appear in a wide range of correlated materials. Electronic localization–delocalization and the expected loss of quasiparticles characterize beyond-Landau metallic quantum critical points and the associated strange metals. Typical settings involve local spins. Systems that contain entwined degrees of freedom offer new platforms to realize unusual forms of quantum criticality. Here, we study the fate of an SU(4) spin–orbital Kondo state in a multipolar Bose–Fermi Kondo model, which provides an effective description of a multipolar Kondo lattice, using a renormalization-group method. We show that at zero temperature, a generic trajectory in the model’s parameter space contains two quantum critical points, which are associated with the destruction of Kondo entanglement in the orbital and spin channels, respectively. Our asymptotically exact results reveal an overall phase diagram, provide the theoretical basis to understand puzzling recent experiments of a multipolar heavy fermion metal, and point to a means of designing different forms of quantum criticality and strange metallicity in a variety of strongly correlated systems.
Regulating cathode surface hydroxyl chemistry enables superior potassium storage
Authors: Fu Qingfeng , Peng Chi , Zhou Wang , Zhang Xiangni , Yang Keke , Chen Lanzi , Mo Ying , Wu Jian-Fang , Gao Peng , Fan Changling , Xu Chaohe , Wang Zhaohui , Liu Jilei
Published: July 2023

Potassium vanadium fluorophosphate (KVPO
4
F) is regarded as a promising cathode candidate for potassium-ion batteries due to its high working voltage and satisfactory theoretical capacity. However, the usage of electrochemically inactive binders and redundant current collectors typically results in inferior electrochemical performance and low energy density, thus implying the important role of rational electrode structure design. Herein, we have reported a scalable and cost-effective synthesis of a cellulose-derived KVPO
4
F self-supporting electrode, which features a special surface hydroxyl chemistry, three-dimensional porous and conductive framework, as well as super flexible and stable architecture. The cellulose not only serves as a flexible substrate, a pore-forming agent, and a versatile binder for KVPO
4
F/conductive carbon but also enhances the K-ion migration ability. Benefiting from the special hydroxyl chemistry-induced storage mechanism and electrode structural stability, the flexible freestanding KVPO
4
F cathode exhibits high-rate performance (53.0% capacity retention with current densities increased 50-fold, from 0.2 C to 10 C) and impressive cycling stability (capacity retention up to 74.9% can be achieved over 1,000 cycles at a rate of 5 C). Such electrode design and surface engineering strategies, along with a deeper understanding of potassium storage mechanisms, provide invaluable guidance for better electrode design to boost the performance of potassium-ion energy storage systems.
Contact between water vapor and silicate surface causes abiotic formation of reactive oxygen species in an anoxic atmosphere
Authors: Xia Yu , Li Juan , Zhang Yuanzheng , Yin Yongguang , Chen Bolei , Liang Yong , Jiang Guibin , Zare Richard N.
Published: July 2023

Spontaneous generation of reactive oxygen species (ROS) in aqueous microdroplets or at a water vapor–silicate interface is a new source of redox chemistry. However, such generation occurs with difficulty in liquid water having a large ionic strength. We report that ROS is spontaneously produced when water vapor contacts hydrogen-bonded hydroxyl groups on a silicate surface. The evolution of hydrogen-bonded species such as hydroxyl groups was investigated by using two-dimensional, time-resolved FT-IR spectroscopy. The participation of water vapor in ROS generation is confirmed by investigating the reaction of D
2
O vapor and hydroxyl groups on a silicate surface. We propose a reaction pathway for ROS generation based on the change of the hydrogen-bonding network and corresponding electron transfer onto the silicate surface in the water vapor–solid contact process. Our observations suggest that ROS production from water vapor–silicate contact electrification could have contributed to oxidation during the Archean Eon before the Great Oxidation Event.
Structural insights into redox signal transduction mechanisms in the control of nitrogen fixation by the NifLA system
Authors: Boyer Nathaniel R. , Tokmina-Lukaszewska Monika , Bueno Batista Marcelo , Mus Florence , Dixon Ray , Bothner Brian , Peters John W.
Published: July 2023

NifL is a conformationally dynamic flavoprotein responsible for regulating the activity of the σ54-dependent activator NifA to control the transcription of nitrogen fixation (nif) genes in response to intracellular oxygen, cellular energy, or nitrogen availability. The NifL-NifA two-component system is the master regulatory system for nitrogen fixation. NifL serves as a sensory protein, undergoing signal-dependent conformational changes that modulate its interaction with NifA, forming the NifL–NifA complex, which inhibits NifA activity in conditions unsuitable for nitrogen fixation. While NifL-NifA regulation is well understood, these conformationally flexible proteins have eluded previous attempts at structure determination. In work described here, we advance a structural model of the NifL dimer supported by a combination of scattering techniques and mass spectrometry (MS)-coupled structural analyses that report on the average structure in solution. Using a combination of small angle X-ray scattering-derived electron density maps and MS-coupled surface labeling, we investigate the conformational dynamics responsible for NifL oxygen and energy responses. Our results reveal conformational differences in the structure of NifL under reduced and oxidized conditions that provide the basis for a model for modulating NifLA complex formation in the regulation of nitrogen fixation in response to oxygen in the model diazotroph,Azotobacter vinelandii.
An interchangeable prion-like domain is required for Ty1 retrotransposition
Authors: Beckwith Sean L. , Nomberg Emily J. , Newman Abigail C. , Taylor Jeannette V. , Guerrero-Ferreira Ricardo C. , Garfinkel David J.
Published: July 2023

Retrotransposons and retroviruses shape genome evolution and can negatively impact genome function.
Saccharomyces cerevisiae
and its close relatives harbor several families of LTR-retrotransposons, the most abundant being Ty1 in several laboratory strains. The cytosolic foci that nucleate Ty1 virus-like particle (VLP) assembly are not well understood. These foci, termed retrosomes or T-bodies, contain Ty1 Gag and likely Gag-Pol and the Ty1 mRNA destined for reverse transcription. Here, we report an intrinsically disordered N-terminal
pr
ion-
l
ike
d
omain (PrLD) within Gag that is required for transposition. This domain contains amino acid composition similar to known yeast prions and is sufficient to nucleate prionogenesis in an established cell-based prion reporter system. Deleting the Ty1 PrLD results in dramatic VLP assembly and retrotransposition defects but does not affect Gag protein level. Ty1 Gag chimeras in which the PrLD is replaced with other sequences, including yeast and mammalian prionogenic domains, display a range of retrotransposition phenotypes from wild type to null. We examine these chimeras throughout the Ty1 replication cycle and find that some support retrosome formation, VLP assembly, and retrotransposition, including the yeast Sup35 prion and the mouse PrP prion. Our interchangeable Ty1 system provides a useful, genetically tractable in vivo platform for studying PrLDs, complete with a suite of robust and sensitive assays. Our work also invites study into the prevalence of PrLDs in additional mobile elements.
IL-7R licenses a population of epigenetically poised memory CD8
+
T cells with superior antitumor efficacy that are critical for melanoma memory
Authors: Micevic Goran , Daniels Andrew , Flem-Karlsen Karine , Park Koonam , Talty Ronan , McGeary Meaghan , Mirza Haris , Blackburn Holly N. , Sefik Esen , Cheung Julie F. , Hornick Noah I. , Aizenbud Lilach , Joshi Nikhil S. , Kluger Harriet , Iwasaki Akiko , Bosenberg Marcus W. , Flavell Richard A.
Published: July 2023

Recurrence of advanced melanoma after therapy is a major risk factor for reduced survival, and treatment options are limited. Antitumor immune memory plays a critical role in preventing melanoma recurrence and memory T cells could be a potent cell-based therapy, but the identity, and functional properties of the required immune cells are incompletely understood. Here, we show that an IL-7R
hi
tumor-specific CD8
+
population is critical for antitumor memory and can be epigenetically augmented to drive powerful antitumor immune responses. Using a model of functional antimelanoma memory, we found that high IL-7R expression selectively marks a CD8
+
population in lymphoid organs that plays critical roles in maintaining tumor remission after immunotherapy or surgical resection. This population has intrinsic cytotoxic activity, lacks markers of exhaustion and has superior antitumor efficacy. IL-7Rhi cells have a functionally poised epigenetic landscape regulated by DNA methylation, which can be augmented by hypomethylating agents to confer improved survival and complete melanoma clearance in naive mice. Importantly, greater than 95% of tumor-specific T cells in draining lymph nodes after therapy express high levels of IL-7R. This overlap between IL-7R
hi
and antigen-specific T cells allows for enrichment of a potent functional CD8
+
population without determining antigen-specificity, which we demonstrate in a melanoma model without a known antigen. We identify that IL-7R expression in human melanoma is an independent prognostic factor of improved survival. These findings advance our basic understanding of antitumor memory and suggest a cell-based therapy using high IL-7R expression to enrich for a lymph node population with superior antitumor activity that can be augmented by hypomethylating agents.
SkyPole—A method for locating the north celestial pole from skylight polarization patterns
Authors: Kronland-Martinet Thomas , Poughon Léo , Pasquinelli Marcel , Duché David , Serres Julien R. , Viollet Stéphane
Published: July 2023

True north can be determined on Earth by three means: magnetic compasses, stars, and via the global navigation satellite systems (GNSS), each of which has its own drawbacks. GNSS are sensitive to jamming and spoofing, magnetic compasses are vulnerable to magnetic interferences, and the stars can be used only at night with a clear sky. As an alternative to these methods, nature-inspired navigational cues are of particular interest. Celestial polarization, which is used by insects such as
Cataglyphis
ants, can provide useful directional cues. Migrating birds calibrate their magnetic compasses by observing the celestial rotation at night. By combining these cues, we have developed a bioinspired optical method for finding the celestial pole during the daytime. This method, which we have named SkyPole, is based on the rotation of the skylight polarization pattern. A polarimetric camera was used to measure the degree of skylight polarization rotating with the Sun. Image difference processes were then applied to the time-varying measurements in order to determine the north celestial pole’s position and thus the observer’s latitude and bearing with respect to the true north.
DPPA5A suppresses the mutagenic TLS and MMEJ pathways by modulating the cryptic splicing of
Rev1
and
Polq
in mouse embryonic stem cells
Authors: Jiang Fangjie , Wang Lin , Dong Yuping , Nie Wenhui , Zhou Hu , Gao Jing , Zheng Ping
Published: July 2023

Genetic alterations are often acquired during prolonged propagation of pluripotent stem cells (PSCs). This ruins the stem cell quality and hampers their full applications. Understanding how PSCs maintain genomic integrity would provide the clues to overcome the hurdle. It has been known that embryonic stem cells (ESCs) utilize high-fidelity pathways to ensure genomic stability, but the underlying mechanisms remain largely elusive. Here, we show that many DNA damage response and repair genes display differential alternative splicing in mouse ESCs compared to differentiated cells. Particularly,
Rev1
and
Polq
, two key genes for mutagenic translesion DNA synthesis (TLS) and microhomology-mediated end joining (MMEJ) repair pathways, respectively, display a significantly higher rate of cryptic exon (CE) inclusion in ESCs. The frequent CE inclusion disrupts the normal protein expressions of REV1 and POLθ, thereby suppressing the mutagenic TLS and MMEJ. Further, we identify an ESC-specific RNA binding protein DPPA5A which stimulates the CE inclusion in
Rev1
and
Polq
. Depletion of DPPA5A in mouse ESCs decreased the CE inclusion of
Rev1
and
Polq
, induced the protein expression, and stimulated the TLS and MMEJ activity. Enforced expression of DPPA5A in NIH3T3 cells displayed reverse effects. Mechanistically, we found that DPPA5A directly regulated CE splicing of
Rev1
. DPPA5A associates with U2 small nuclear ribonucleoprotein of the spliceosome and binds to the GA-rich motif in the CE of
Rev1
to promote CE inclusion. Thus, our study uncovers a mechanism to suppress mutagenic TLS and MMEJ pathways in ESCs.
Honey bees switch mechanisms to drink deep nectar efficiently
Authors: Wei Jiangkun , Rico-Guevara Alejandro , Nicolson Susan W. , Brau Fabian , Damman Pascal , Gorb Stanislav N. , Wu Zhigang , Wu Jianing
Published: July 2023

The feeding mechanisms of animals constrain the spectrum of resources that they can exploit profitably. For floral nectar eaters, both corolla depth and nectar properties have marked influence on foraging choices. We report the multiple strategies used by honey bees to efficiently extract nectar at the range of sugar concentrations and corolla depths they face in nature. Honey bees can collect nectar by dipping their hairy tongues or capillary loading when lapping it, or they can attach the tongue to the wall of long corollas and directly suck the nectar along the tongue sides. The honey bee feeding apparatus is unveiled as a multifunctional tool that can switch between lapping and sucking nectar according to the instantaneous ingesting efficiency, which is determined by the interplay of nectar–mouth distance and sugar concentration. These versatile feeding mechanisms allow honey bees to extract nectar efficiently from a wider range of floral resources than previously appreciated and endow them with remarkable adaptability to diverse foraging environments.
Archean phosphorus recycling facilitated by ultraviolet radiation
Authors: Farr Orion , Hao Jihua , Liu Winnie , Fehon Nolan , Reinfelder John R. , Yee Nathan , Falkowski Paul G.
Published: July 2023

Of the six elements incorporated into the major polymers of life, phosphorus is the least abundant on a global scale [E. Anders, M. Ebihara,
Geochim. Cosmochim. Acta
46, 2363–2380 (1982)] and has been described as the “ultimate limiting nutrient” [T. Tyrrell,
Nature
400, 525–531 (1999)]. In the modern ocean, the supply of dissolved phosphorus is predominantly sustained by the oxidative remineralization/recycling of organic phosphorus in seawater. However, in the Archean Eon (4 to 2.5 Ga), surface waters were anoxic and reducing. Here, we conducted photochemical experiments to test whether photodegradation of ubiquitous dissolved organic phosphorus could facilitate phosphorus recycling under the simulated Archean conditions. Our results strongly suggest that organic phosphorus compounds, which were produced by marine biota (e.g., adenosine monophosphate and phosphatidylserine) or delivered by meteorites (e.g., methyl phosphonate) can undergo rapid photodegradation and release inorganic phosphate into solution under anoxic conditions. Our experimental results and theoretical calculations indicate that photodegradation of organic phosphorus could have been a significant source of bioavailable phosphorus in the early ocean and would have fueled primary production during the Archean eon.
Discourses and practices of the ‘New Normal’
Authors: Krzyżanowski Michał , Wodak Ruth , Bradby Hannah , Gardell Mattias , Kallis Aristotle , Krzyżanowska Natalia , Mudde Cas , Rydgren Jens
Published: July 2023

This position paper argues for an interdisciplinary agenda relating crises to on-going processes of normalization of anti- and post-democratic action. We call for exploring theoretically and empirically the ‘new normal’ logic introduced into public imagination on the back of various crises, including the recent ‘Refugee Crisis’ in Europe, COVID-19 pandemic, or the still ongoing Russian invasion of Ukraine. Gathering researchers of populism, extremism, discrimination, and other formats of anti- and post-democratic action, we propose investigating how, why, and under which conditions, discourses and practices underlying normalization processes re-emerge to challenge the liberal democratic order. We argue exploring the multiple variants of ‘the new normal’ related to crises, historically and more recently. We are interested in how and why these open pathways for politics of exclusion, inequality, xenophobia and other patterns of anti- and post-democratic action while deepening polarization and radicalization of society as well as propelling far-right politics and ideologies.
Plasma-sprayed Al2O3-TiB2-SiC ternary composite coatings and its wear behaviour based on SiC content
Authors: Mirhosseini Seyed Hossein , Mosallaee Masoud , Razavi Mansour , Fotouhi Mohammad
Published: July 2023

This paper aims to study the effect of adding different SiC content on the wear performance of Al2O3-TiB2-SiC ternary composite coatings produced by the air plasma spraying process. The study used SHS powders as primary materials, consisting of H3BO3, Al, and TiO2, and 5, 10, and 15 Vol.% SiC. The microstructure and wear specifications of the coatings were characterised using FESEM, microhardness, and pin-on-disk methods. The results showed that the addition of SiC led to higher hardness and lower wear track width and rate compared to Al2O3-TiB2 composite coatings. The best wear behaviour was observed in Al2O3-TiB2-10%SiC and 15 wt% SiC composite coatings. The main wear mechanisms were found to be brittle fracture, delamination and adhesive for all samples.
Multi-photon annihilation in the negatively charged positronium ion
Authors: Frolov Alexei M
Published: July 2023

The total energy and other bound state properties of the ground (bound) 11
S-state in the Ps− (or e
−
e
+
e
−) ion are determined to very high accuracy. Our best variational energy for the ground state in this ion equals E=-0.26200507023298010777040225 a. u. , which is the lowest variational energy ever obtained for this ion. By using our highly wave functions we evaluated (to very high accuracy) a large number of different expectation values (or properties) of the Ps− ion which have never been considered in earlier studies. This includes a number of

〈

r

ij

k

〉

expectation values (where 5 ≤ k ≤ 11), all independent quasi-singular

〈

r

ij

r

jk

r

ij

3

〉

and singular

〈

1

r

ij

3

〉

expectation values, etc. Our highly accurate expectation values of the electron-positron delta-function of the Ps− ion are used to evaluate (to very high accuracy) the rates of two-, three-, four- and five-photon annihilation. The numerical values of these rates provide the highly accurate and complete solution of the multi-photon annihilation in the negatively charged positronium ion.
Ab-initio simulations of Rb2CuMCl6 (M = Sb, Bi) for photovoltaics and thermoelectric device applications
Authors: Khan M Aslam , Niaz Shanawer , Noor N A , Mumtaz Sohail , Mahmood Asif
Published: July 2023

Due to their extraordinarily flexible optoelectronic properties, the research on non-toxic double-perovskite halides has recently become very attractive. We use density functional theory to analyze the optical, electronic, and thermoelectric characteristics of copper-based double-perovskite halides, Rb2CuMCl6 (M = Sb, Bi). The band structures obtained with the Tran-Blaha altered Becke-Johnson potential demonstrate that altering the cations from Sb to Bi results in bandgap adjustments from infrared to visible (i.e. 1.0–1.2 eV) energy. Because of replacing Sb with Bi, the optical absorption exhibits utmost absorption within the ultraviolet region, whereas the absorption edge is shifted from infrared to the visible light region. Furthermore, the transport parameters are compatible with other estimated thermoelectric parameters. The fact that Rb2CuSbCl6 has a higher Seebeck coefficient indicates that a narrower band gap is appropriate for thermoelectric applications compared with Rb2CuBiCl6. In general, the Rb2CuMCl6 (M = Sb, Bi) is suitable for Sun-absorption devices and energy conversion, according to this computational thermoelectric and optical study.
A virtual flow meter downstream of various elbow configurations
Authors: Weissenbrunner A , Ekat A , Straka M , Schmelter S
Published: July 2023

When flow meters are installed in disturbed flow conditions caused by pipe configurations such as junctions or elbows, significant measurement errors can occur. With existing knowledge of the flow conditions, those errors can be corrected using suitable calibration factors. This paper presents a surrogate model based on computational fluid dynamics simulation results that can predict velocity profiles downstream of single and double elbows in- and out-of-plane. The simulated flow profiles are decomposed into a fully-developed and a disturbed part, which allows changing the Reynolds number and roughness of the pipe wall without performing additional simulations. Furthermore, proper orthogonal decomposition and interpolation using piecewise linear splines enables the real-time evaluation of the model for a wide range of curvature radii and distances between the elbows. By incorporating a measurement principle, calibration factors for different flow meter designs can be predicted. The model is validated on the example of an ultrasonic flow meter by comparison with measurement data obtained from a clamp-on flow meter.
Numerical studies on aerodynamic performance of NACA 0018 profile in fundamental and research application of the aerospace industry
Authors: Apostol E I , Ţîţu A M
Published: July 2023

For a good functioning of the activities carried out within research institutions both at managerial level and for fulfilling the technical requirements, we aim to determine the aerodynamic characteristics of the standard profiles used in the aerospace field by testing in the subsonic tunnel. We also intend to conduct a study based on numerous experimental tests performed in wind tunnels that can be compared to the actual scale of the aircraft for structural integrity and improving its performance. The purpose of this paper is to evaluate the dynamics of fluid separation, lift and drag. This allows us to further improve the profiles so that it is essential to improve the efficiency and performance of an aircraft in terms of improving lift and reducing drag. In the present research, numerical and experimental studies are performed on a finite geometry of the NACA0018 wing at different angles of attack and Reynolds numbers. This paper aims to improve the performance, accuracy and quality of testing, increase the competitiveness of similar installations on the world market, ensure the national research and development capacity of new products in the aeronautical and defense industry.
The mathematics approaches in the analysis of mathematics syllabuses similarities among Japanese and Bosnia and Herzegovina universities
Authors: Milijevic M , Preradovic Kulovac D
Published: July 2023

The goal of our research is improvement of mathematics curriculum and popularization of mathematics among students of economics in developing countries. We analyze and compare curricula of pure mathematics courses that are taught to university students of faculties of economics in Japan and in Bosnia and Herzegovina. Data set contains math syllabuses in 2021/22 school year from six public universities in Bosnia and Herzegovina and seven from Japan. The text corpus was pre-processed and then the Term Frequency – Inverse Document Frequency algorithm, and Sentence Transformed Multi QA model were applied to build word vectors, find the similarity among Japanese and Bosnia and Herzegovina mathematics syllabuses using cosine similarity approach, and to find the key competences of these two countries mathematics syllabuses using the word cloud. Our results show the following similarity between the curricula: 60.7 percent using TF-IDF and 80.3 percent using Multi QA model. The key competences in the Japanese mathematics course are narrow and focused, in contrast to Bosnia and Herzegovina’s.
Computer aided design of low voltage electrical installations
Authors: Predus M F , Muscai C M , Popescu C , Hatiegan C
Published: July 2023

The paper proposes a method of calculation and rapid sizing of power circuits of electrical panels using a program made in-house. The proposed application has a friendly and very intuitive graphical interface, being easy to use due to the intelligent way of making the selection and data entry. This application emerged in response to the real need for fast and accurate sizing of low voltage electrical switchboards used in industry. The real help is provided by the mechanism that allows frequent and rapid modification of the technical solution to adapt to the ever-changing requirements dictated by the stages in the development of electrical projects.The operation of the program is based on the existence of an internal database materialized using several data tables containing various types of electrical consumers, switching and protection equipment and a series of standardized power cables from which they are automatically selected. The selection is made based on sizing and verification calculations with the help of intelligent selection methods so that only the equipment that matches the data provided by the user are selected ensuring an additional verification of the various omissions that may occur.The application is useful for designing of a new installation or for the verification of existing ones, allowing the rapid and even real-time observation of the influence of the various changes made to the project.
PyDigitizer – A Python module for digitizing 2D curves
Authors: Nedelcu D , Latinovic T , Sikman L
Published: July 2023

The paper presents a PyDigitizer application designed to extract numerical coordinates of existing curves from image format. The application is created in the Python programming language and offers the possibility of manual extraction of curve coordinates, intersection of curves with user-specified abscissa or ordinate, generation of polynomial regression equations of curves. All generated information (coordinates, intersection points, regression curves) can be exported to Microsoft Excel. Also, point coordinates of Excel curves can be loaded into PyDigitizer to obtain polynomial regression curves or intersections.
Romania in the energy transition, for small prosumers - post pandemic and the Ukraine war
Authors: Blaj M A , Deaconu S I
Published: July 2023

Prior to the COVID 19 pandemic, Romania demonstrated enormous progress in the context of sustainable electricity production from renewable sources. Mainly motivated by easy access to the electricity exchange for these new producers and the appetite of the younger generation for clean energy. However, outside all development and improvements on the production side, and added new production capacity, the distribution and quality of the electricity supplied to end customers kept deteriorating. Small consumers, both private and industrial, must bear all the disturbances caused by the ageing distribution installations. For such situations, the solution came in the form of micro-grids and expansion of new electricity generation capabilities at local level, more adapted to consumers. This paper follows up on two previously introduced practical examples with such solutions, with new advantages and disadvantages, from, both, a technological and commercial perspective.
Tribological aspects of nano-particle fluid based cooling and lubrication in milling process
Authors: Sredanovic B , Globocki-Lakic G , Dugic P , Borkovic A
Published: July 2023

The introduction of different additives into the cooling and lubrication systems in the metal cutting process, contributed to improving the machining process sustainability. Different types of additives can help to reduce friction, reduce wear of contact surfaces, improve heat dissipation from the cutting zone, etc. With the development of nanotechnology, great focus has been placed on the investigation and using of nano-particles, nano-additives and nanofluids in industry. In this paper, the effects of using the nano-particle based cooling and lubrication fluid are investigated. There are performed comparison effects of standard cooling and lubrication fluids versus nanofluids based cooling and lubrication on cutting process performance. Molybdenum disulphide particles are used as nano-particles, which dispersed in a standard cooling and lubrication fluid. As workpiece was used alloyed tool steel. Milling process performance indicators was analysed based on Taguchi experimental plan, for different cooling and lubrication condition and process parameters. Cutting forces component in three perpendicular axes, and machined surface parameters were measured. Experimental analysis has shown that the use of nano-particles, which mixed in a standard cooling and lubrication fluid, significantly contributes to the reduction of cutting forces, friction coefficients, more efficient cutting and generation of machined surfaces.
Measurement of thermal conductivity of the cortical bone: experimental studies and comparative analysis
Authors: Zawadzki P , Patalas A , Labudzki R , Talar R
Published: July 2023

Thermal conductivity is an ambiguous material property of bone tissue that directly impacts the surgical procedure and the patient’s convalescence (thermal necrosis). The study aimed to determine the thermal coefficient experimentally and compare the results with previous results. The comparative method was used with the reference material, PMMA, with a coefficient value of 0.167 W*(mK)−1 to measure the thermal conductivity. Thanks to the obtained results, the thermal diffusivity coefficient was also determined. The results allowed to choose the coefficient of thermal conductivity at the level: 0.26-0.34 W*(mK)−1 and thermal diffusivity: 0.103-0.135 mm2*s−1. The confrontation of the results established their compliance with the latest research. The thermal conductivity coefficient varies depending on the condition of the tissue (dry or fresh) and its porosity. Due to its anisotropic structure, bone tissue can change its thermal properties depending on its location (body or head). Further extensive experimental evaluation of these properties is required.
The dependance of breakage energy on the grain size for selected biomaterials
Authors: Kruszelnicka W
Published: July 2023

The aim of this research is to expand the knowledge on the description of the grains breakage energy. In effect of the research a model to describe the rice and corn grains breakage energy in dependance of size was developed. This was achieved by linking the level of grinding energy with the properties of the material (particle size) and the loading conditions. The selected grains (rice and corn) were subjected to loads (compression and cutting) on a testing machine. Based on the force-displacement curves, the relationship between the energy necessary to cause a breakage and particle size was described. The results show, that the energy needed for grain shearing changes with the particle size according to the power law, similarly to brittle materials. Through proposed modeling approach, it will be possible to reduce undesirable grain damage as well as improve the operation and design of processing machines in terms of their energy consumption and efficiency.
Radiographic film waste management and recovery
Authors: Ardelean E , Ardelean M , Galfi C , Socalici A , Josan A
Published: July 2023

Health facilities in Romania generate hundreds of thousands of tons of medical waste (hazardous and non-hazardous) annually. It is therefore necessary to apply a rigorous management of this waste, in compliance with applicable regulations, especially in the case of waste with a high potential for harmfulness. In the context of the global PANDEMIC of COVID 19, the amount of radiographic films generated has increased, using the classic variant when the moderns investigative devices was no longer available. The legislation requires hospitals and clinics to follow certain rules regarding the management of X-rays films. These are considered private information and must be managed according to the legislation, but silver and other chemicals in the film are toxic to the environment when are disposed uncontrolled. Recycling companies prefer to recover silver from effluents used to obtain classical radiography, recovery that is done by electrolysis and does not require large investments.

The paper presents a relatively simple technology of recycling the radiographic films starting from laboratory studies, by leaching them in sodium hydroxide solution and the implications from the point of view of managing such activities.
Structural design of architectural 3D printing equipment
Authors: Wu Liang , Wu Changzhong , Tian Jiaxin
Published: July 2023

Referring to the development status of building 3D printing equipment at home and abroad, this paper compares various schemes, and designs and analyzes the performance parameters of the mechanical system and various mechanisms of building 3D printing equipment. The detailed design scheme of each component is present and provides a reference for the development of 3D printing equipment for large buildings in the future.
The Bearing Capacity of Composite Insulated Cross Arm Tower under Typhoon Load
Authors: Zhu Binrong , Zhang Hongjie , Sun Qigang , He Chunhui , Xing Haijun
Published: July 2023

Typhoon meteorological disasters occur frequently, which seriously threaten the safe and stable operation of old transmission lines. The old transmission towers can be retrofitted with composite insulated cross arms to solve the problems of low capacity of wind protection design and insufficient distance between conductor and ground. The paper analyzes the wind load and bearing capacity of composite insulated cross-arm towers under the action of a typhoon through theoretical calculation and finite element analysis and puts forward the calculation method of wind load under the action of a typhoon, and it is revealed that typhoon has less influence on the force of composite cross arm and greater influence on the deformation of the composite cross-arm. Finally, the bearing capacity of a composite insulated cross-arm tower under typhoon load is proposed.