bluuebunny/crossref_metadata_2025 huggingface dataset:
Association between adiponectin single nucleotide polymorphisms and the risk of diabetic polyneuropathy
Authors: Bakr Noha M. , Hashim Noha A. , Ibrahim Nevin F. , Saadawy Sara F.
Published: January 2025

Genetic factors play a significant role in the occurrence and clinical course of diabetic peripheral neuropathy (DPN). This research aimed to search the influence of adiponectin single nucleotide polymorphisms (SNPs) on the risk of developing and the severity of DPN in Egyptian patients. Adiponectin SNPs were genotype in 360 participants comprising diabetic sufferers with and without peripheral neuropathy and healthy volunteers via the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) approach. Regarding the + 45 T/G SNP, the TG/ and GG genotypes and the G allele were linked to an rised risk of DPN by comparing the DPN group with both the control and diabetic patients without peripheral neuropathy (DWPN) groups, and when comparing the DWPN group with the control group. Concerning + 276 G/T SNP, the GT genotype and T allele were linked to a declined risk of occuring DPN when comparing the DPN group with both other groups. Patients with DPN had greater frequencies of the GA genotype of the − 11,391 G/A SNP than individuals in the control group, while patients with DPN had greater frequencies of the AA genotype than patients in the DWPN group. Regarding clinic-pathological features, a meaningful rise in the mean values of fasting blood glucose (FBG), duration of the disease, and Toronto Clinical Neuropathy Severity Score (TCSS) were noted in the + 45 GG genotype and G allele carriers. Contrariwise, the + 276 TT genotype carriers had lower mean values for the same clinic-pathological features. For the T allele carriers, the same results were observed in case of duration of the disease and TCSS value. Our results concluded that adiponectin + 45 T/G SNP could be a risk factor considering DPN and the severity of the disease. The − 11391G/A SNP might be associated with DPN. In addition, + 276 G/T SNP could be a protective factor regarding DPN and the severity of the disease.
Psychological differences in food addiction and binge eating in a general Polish population
Authors: Różycka Jagoda , Nowacki Ari , Łukowska Marta , Sokołowska Maryla , Zielińska Joanna , Duszkiewicz Roksana , Stojek Monika M.
Published: January 2025

The aim of the study was to identify the prevalence of food addiction (FA) and binge eating (BE) in a general Polish population, to explore the differences between these constructs, and to examine psychological differences among FA, BE, and FA + BE groups. 2123 participants completed the questionnaires: Yale Food Addiction Scale 2.0, Binge Eating Scale, The PTSD Checklist for DSM-5, Life Events Checklist, Adverse Childhood Experiences, Short UPPS-P scale (impulsive traits), Dutch Eating Behavior Questionnaire and Depression, Anxiety and Stress Scale − 21 items. 492 participants reported clinically significant symptoms of FA, BE, or both. Spearman’s correlations, Mann-Whitney U tests, and Kruskal-Wallis tests were performed to examine the relationships between variables. The present study showed that FA and BE symptoms are common in the adult sample. The FA, BE and FA + BE groups had higher scores than the control group for all variables included in the study. The FA + BE group presented a significantly higher level of behavioral and emotional symptoms, followed by the FA and the BE group with less severity of symptoms. This study supports the hypothesis of food addiction as a similar construct to BE. FA is a broader concept than BE, but individuals experiencing both indicated the greatest functional difficulties.
Differences in risk factor profiles for peripheral artery disease compared to coronary, cerebral and carotid artery
Authors: Acosta Stefan , Du Yufeng , Borné Yan , Gottsäter Anders
Published: January 2025

The aim of this study was to evaluate the greatest drivers for development of lower extremity peripheral artery disease (PAD) in relation to coronary, precerebral, or cerebral artery disease This prospective study (Malmö Diet and Cancer study) included 26,681 participants. The diagnosis of incident PAD, coronary artery disease (CoAD), atherothrombotic ischemic stroke (IS) free from atrial fibrillation or flutter, and carotid artery disease (CaAD) was validated. A modified Lunn-McNeil competing risk analysis was performed to compare the Hazard Ratio (HR) strength of PAD in relation to CoAD, IS, or CaAD. The estimated population attributable risk fractions (PAF) for each atherosclerotic manifestation were estimated by first fit an age and sex adjusted Cox proportional hazard regression, and then estimate the PAF using the Direct method. Male sex, age, and hypertension were risk factors for development of all atherosclerotic manifestations. Current smoking accounted for 45.6% (95% CI 41.1–47.2), 16.1%, 14.0%, and 23.3% of the risk for development of PAD, CoAD, IS, and CaAD, respectively. Hypertension was more associated with development of PAD than CoAD (p = 0.009). Smoking and diabetes mellitus were positively associated with all four manifestations, but these associations were significantly stronger for PAD than the other three manifestations. Smoking and diabetes mellitus had a larger impact on incident PAD than incident coronary, cerebral or precerebral artery manifestations. Since the lower extremity arteries are the easiest to access and examine, they may be considered as the first arterial bed to examine in patients at increased risk for atherosclerotic manifestations.
Impact of ionomers on porous Fe-N-C catalysts for alkaline oxygen reduction in gas diffusion electrodes
Authors: Zhu Jinjie , Pedersen Angus , Kellner Simon , Hunter Robert D. , Barrio Jesús
Published: January 2025

Alkaline exchange membrane fuel cells (AEMFCs) offer a promising alternative to the traditional fossil fuel due to their ability to use inexpensive platinum group metal (PGM)-free catalysts, which could potentially replace Platinum-based catalysts. Iron coordinated in nitrogen-doped carbon (Fe-N-C) single atom electrocatalysts offer the best Pt-free ORR activities. However, most research focuses on material development in alkaline conditions, with limited attention on catalyst layer fabrication. Here, we demonstrate how the oxygen reduction reaction (ORR) performance of a porous Fe-N-C catalyst is affected by the choice of three different commercial ionomers and the ionomer-to-catalyst ratio (I/C). A Mg-templated Fe-N-C is employed as a catalyst owing to the electrochemical accessibility of the Fe sites, and the impact of ionomer properties and coverage were studied and correlated with the electrochemical performance in a gas-diffusion electrode (GDE). The catalyst layer with Nafion at I/C = 2.8 displayed the best activity at high current densities (0.737 ± 0.01 VRHE iR-free at 1 A cm⁻²) owing to a more homogeneous catalyst layer, while Sustainion displayed a higher performance in the kinetic region at the same I/C. These findings provide insights into the impact of catalyst layer optimization to achieve optimal performance in Fe-N-C based AEMFCs.
A single-crystal 3D Zn-tetrathiolate connected metal–organic framework
Authors: Li Jian-Rong , Hu Jieying , Jiang Long , He Yonghe , Liao Wei-Ming , Yang Xianghua , Chung Lai-Hon , He Jun
Published: January 2025

Masked hexakis(thio)triphenylene, HVaTT (boy wearing a mask), deprotects (dropping off the mask) and chelates Zn(ii) ions (boy grasping the Zn(ii) ball) to form a single-crystal 3-fold interpenetrating Zn-tetrathiolate framework (HTT-Zn).
Insights into the mechanism of electrochemical chloride oxidation in ethanol from X-ray photoelectron spectroscopy, quiescent solution voltammetry, and rotating ring-disk electrodes
Authors: Van Daele Ryan D. , Li Siqi , Morrissey Katherine H. , Bartlett Bart M.
Published: January 2025

A combination of XPS analysis and RRDE experiments supports chloride adsorption with electron transfer as chloride is oxidized in ethanol solvent to form ethyl hypochlorite.
A DFT mechanistic study on nickel-catalyzed arylation of amino alcohols with aryl electrophiles: insights into the origins of chemoselectivity
Authors: Shan Chao , Zhang Zhiqiang , You Junyan , Li Ranran , Ma Xuexiang
Published: January 2025

DFT calculations fully rationalize the mechanistic details and origins of chemoselectivity for nickel-catalyzed arylation of amino alcohols with aryl electrophiles.
Membrane potential fluctuations and water asymmetry on plasma cell and model lipid membranes: origins, implications and properties
Authors: Li Zhi , Swiderska Iwona , Dalifoski Lena , Lee Seonwoo , Correa-Rojas Nelson Alonso , Roesel David , Eremchev Maksim , Flór Mischa , Tarun Orly , Marchioro Arianna , Roke Sylvie
Published: January 2025

Membrane potential fluctuations have previously been detected by second harmonic (SH) water imaging on neuronal cells and model lipid bilayer membranes. We report that such fluctuations are also visible when...
Hinokitiol potentiates antimicrobial activity of bismuth drugs: a combination therapy for overcoming antimicrobial resistance
Authors: Ip Tiffany Ka-Yan , Wang Yuchuan , Wang Suyu , Pu Keyuan , Wang Runming , Han Bingjie , Gao Peng , Xie Yanxuan , Kao Richard Y. , Ho Pak-Leung , Li Hongyan , Sun Hongzhe
Published: January 2025

This study reveals the synergy of hinokitiol and bismuth drugs against antibiotic-resistant bacteria. Their combination enhances antimicrobial efficacy, showing broad-spectrum activity and promising potential to combat antimicrobial resistance.
Photoactivation of the cGAS-STING pathway and pyroptosis by an endoplasmic reticulum-targeting ruthenium(ii) complex for cancer immunotherapy
Authors: Liang Bin-Fa , Jiang Shan , Zhi Yun-Shi , Pan Zheng-Yin , Su Xiu-Qing , Gong Qin , He Zhen-Dan , Yao Da-Hong , He Liang , Li Chen-Yang
Published: January 2025

A cholic acid-modified ruthenium(ii) (Ru1) photosensitizer was synthesized. Ru1 induced pyroptosis and sequentially engaged the downstream proteins p-TBK1 and p-IRF3 within the STING pathway, thus promoting the elicitation of tumor immune responses.
Advances in organic room-temperature phosphorescence: design strategies, photophysical mechanisms, and emerging applications
Authors: Yang Yujie , Li Qianqian , Li Zhen
Published: January 2025

Organic room-temperature phosphorescence can be facilitated according to rational design principles that promote intersystem crossing and decrease non-radiative decay in aggregated states, demonstrating versatile applications across multiple fields.
A facile synthesis of CF3-containing iminoisobenzofurans via copper-catalyzed oxygen trifluoromethylation–cyclization of o-vinyl-N-alkylamide
Authors: Gao Shuo , Zhou Qiwang , Liu Zilin , Xie Shengxing , Yang Di , Zhang Kaiyuan , Zhang Zhenhua
Published: January 2025

A copper-catalyzed oxygen trifluoromethylation of o-vinyl-N-alkylamide using Togni reagent as the trifluoromethyl precursor is demonstrated for the efficient synthesis of trifluoromethyl-containing iminoisobenzofurans.
Fabrication and characterization of an Al2O3/OPSZ/Al2O3 barrier film on a PEN substrate via PEALD and spray-spin coating techniques
Authors: Sun Xiaojie , Feng Wei
Published: January 2025

The introduction of an organic layer (OPSZ) is advantageous for promoting the properties of a multilayer film, such as water vapor barrier performance.
Structural glycobiology – from enzymes to organelles
Authors: Mycroft-West Courtney J. , Leanca Miron A. , Wu Liang
Published: January 2025

Biological carbohydrate polymers represent some of the most complex molecules in life, enabling their participation in a huge range of physiological functions. The complexity of biological carbohydrates arises from an extensive enzymatic repertoire involved in their construction, deconstruction and modification. Over the past decades, structural studies of carbohydrate processing enzymes have driven major insights into their mechanisms, supporting associated applications across medicine and biotechnology. Despite these successes, our understanding of how multienzyme networks function to create complex polysaccharides is still limited. Emerging techniques such as super-resolution microscopy and cryo-electron tomography are now enabling the investigation of native biological systems at near molecular resolutions. Here, we review insights from classical in vitro studies of carbohydrate processing, alongside recent in situ studies of glycosylation-related processes. While considerable technical challenges remain, the integration of molecular mechanisms with true biological context promises to transform our understanding of carbohydrate regulation, shining light upon the processes driving functional complexity in these essential biomolecules.
Dust characterization of protoplanetary disks: A guide to multi-wavelength analyses and accurate dust mass measurements
Authors: Viscardi Elena , Macías Enrique , Zagaria Francesco , Sierra Anibal , Jiang Haochang , Yoshida Tomohiro , Curone Pietro
Published: January 2025

Multi-wavelength dust continuum observations of protoplanetary disks are essential for accurately measuring two key ingredients of planet formation theories: dust mass and grain size. Unfortunately, they are also extremely time-expensive. Our aim is to investigate the most economic way of performing this analysis by identifying the optimal combination of multi-band observations and angular resolution that provides accurate results. We benchmarked the dust characterization analysis on multi-wavelength observations of a compact disk model with shallow rings, and an extended double-ringed disk model. We tested three different combinations of bands (in the 0.45 mm to 7.46 mm range) to see how optically thick and thin observations aid in the reconstruction of the dust properties for different morphologies and in three different dust mass regimes. We also tested different spatial resolutions (0.05"; 0.1"; 0.2"). Dust properties are robustly measured in a multi-band analysis if optically thin observations are included. For typical disks, this requires wavelengths longer than 3 mm. Instead, from fully optically thick observations alone the dust properties cannot be robustly constrained. A high resolution (< 0.03"-0.05") is fundamental in order to resolve the changes in dust content of substructures. However, lower-resolution results still provide an accurate measurement of the total dust mass and of the level of grain growth of rings. Additionally, we propose a new approach that successfully combines lower- and higher-resolution observations in the multi-wavelength analysis without losing spatial information. We also tested enhancing the resolution of each radial intensity profile individually with a flux reconstruction tool ( Frank ), but we note the presence of artifacts. Finally, we discuss the total dust mass that we derived from the SED analyses and compare it with the traditional method of deriving dust masses from millimeter fluxes. Accurate dust mass measurements from the SED analysis can be derived by including optically thin tracers. On the other hand, single-wavelength flux-based masses are always underestimated. For the 0.87 mm flux, the underestimation can be more than one order of magnitude.
Knowledge and behavior: a study on adoption of best management practices among Sri Lankan shrimp farmers
Authors: Abeykoon Nirukshika D. F. , Kono Hiroichi , Kato Keisuke , Sajiki Takahiro , Athambawa Jiffry
Published: January 2025

Shrimp farming in Sri Lanka is economically advantageous but faces challenges like disease outbreaks and environmental issues. The government has introduced Best Management Practices (BMPs) to ensure sustainability. This study aimed to assess BMP knowledge and adoption among Sri Lankan shrimp farmers while identifying socio-demographic and behavioral factors influencing them, which have not been previously assessed. Data were gathered from 131 shrimp farmers in Puttalam district in Sri Lanka through a questionnaire survey and analyzed using descriptive statistics and ordered logistic regressions. The results showed that 26% of farmers had poor BMP knowledge, while 37% each had fair and good knowledge. Regarding adoption, 2% exhibited poor, 89% fair, and 9% good BMP adoption. According to the ordered logistic regression results, BMP training (p < 0.01), education (p < 0.05), and workforce (p < 0.05) significantly affect the knowledge level of BMPs. In contrast, age (p < 0.05), experience (p < 0.05), income share (p < 0.1), and risk preference (p < 0.1) significantly affect the adoption of BMPs. It is recommended to provide more BMP training to shrimp farmers, to improve their knowledge. Moreover, considering socioeconomic and behavioral factors is crucial when designing policies and interventions to promote BMP adoption.
Fabrication and Dissolution of Americium Plutonium Oxide Fuels
Authors: de Visser – Týnová Eva , Bruin Jessica , Oud Frank
Published: January 2025

As a part of the research on Gen IV oxide fuels the effect of the minor actinides (americium) on the dissolution behaviour of plutonium oxide has been studied. Two compositions of americium plutonium oxide pellets have been fabricated by powder metallurgy in a glovebox specially designed for work with americium. These fresh pellets have been dissolved in hot nitric acid and hot nitric acid with hydrofluoric acid. After a dissolution of 300 minutes, very limited dissolution of just few percent of the starting material was determined, where the dissolution rate of plutonium oxide is about 100 times lower comparing to americium oxide.
Actinide Oxide Dissolution in Tributyl Phosphate
Authors: Gogolski Jarrod , Goetzman Chelsea , Mills Matthew , Nguyen Vinh , Rudisill Tracy , Lascola Robert
Published: January 2025

An alternative to dissolving used nuclear fuel (UNF) in an acidic solution during reprocessing is direct dissolution in an organic solution, which would eliminate an aqueous dissolution step, decrease the amount of nitrate needed, and reduce the facility size. The flowsheet for this potentially less expensive alternative is first to voloxidize the UNF to remove fission product gases and form an oxide. After voloxidation, the UNF is then dissolved in an organic solution containing an extractant mixed with an aliphatic diluent and pre-equilibrated with nitric acid. The organic solution then goes through a solvent extraction process to recover the uranium and/or other desired radionuclides. This work qualitatively studied the dissolution of actinide oxides (UO2, NpO2, and PuO2) in tributyl phosphate using UV-Vis-NIR absorbance spectroscopy to ascertain dissolution behavior. Initial studies included material that is otherwise difficult to dissolve in only nitric acid, specifically CeO2, that is sometimes used as a dissolution surrogate for PuO2. This work confirmed that CeO2, NpO2, and PuO2 are difficult to dissolve in 30 vol% TBP-dodecane pre-equilibrated with 10 M HNO3 and will readily dissolve when co-precipitated with U (i.e., the mixed oxides U-Ce, U-Np, and U-Pu), surrogates for voloxidized nuclear fuel.
Garde ton sang-froid ! Comment inhiber la production post-mortem de GHB endogène ?
Authors: Hadhoum Sarah , Baranger Élisa , Ausseil Mathilde , Kahn Maëva , Costedoat Caroline , Verna Émeline
Published: January 2025

Dans le cadre de l’UE « Méthodologie et travail en mode projet » proposé par le Master humanités médicales de la faculté sciences médicales et paramédicales de l’université Aix-Marseille, les étudiants de Master 1 ont été confrontés aux exigences de l’écriture scientifique.

Le Master est construit autour de la pluridisciplinarité et de l’interdisciplinarité, ce qui en fait sa force et son originalité. L’homme est repositionné dans un cadre diachronique et synchronique dans son environnement biologique, écologique, culturel au centre des problématiques de santé publique. Le défi des étudiants a été de choisir des thèmes de science en apportant la coloration sciences humaines et sociales (SHS) qui caractérise leur formation.

Ces nouvelles représentent l’association synergique des SHS et du monde de la santé en mettant en avant certains enjeux sociétaux actuels et futurs tels que les addictions de différentes natures (comportementales ou biologiques), les problématiques éthiques et déontologiques (recherche biomédicale), les épidémies et les maladies du passé (peste, typhus, anémie, etc.) pour répondre aux enjeux de santé publique actuels.
Feline Shoulder Arthrodesis Using 3D-printed Patient-specific Guides
Authors: Motta Claudio , Condon Anna Maria , Owen Mark Andrew , Craig Andrew , Ridge Patrick Alan , Perez Maria Carolina Perez , Oxley William Henry George
Published: January 2025

Objectives This case series aims to explore the application of 3D-printed patient-specific guides (PSG) in feline shoulder arthrodesis, addressing the scarcity of literature on this procedure in cats. The primary objectives include assessing the feasibility, accuracy, and outcomes of the procedure in four feline cases.

Methods The study employed a retrospective analysis of cases involving feline shoulder arthrodesis performed using PSG. Surgical planning utilized CAD-based techniques, and 3D-printed guides were created for precise osteotomies and implant placement. Follow-ups included radiographic assessments, re-examinations, and owner-reported outcomes.

Results Four feline cases with distinct shoulder issues were successfully treated using PSG. Postoperative management, radiographic evaluations, and long-term follow-ups revealed positive outcomes in terms of limb function and patient activity. The study demonstrates the potential of PSG in achieving accurate humeroscapular alignment in feline shoulder arthrodesis.

Clinical Significance This case series highlights the clinical significance of PSG in enhancing the precision of humeroscapular alignment during feline shoulder arthrodesis. The positive outcomes observed in various shoulder pathologies suggest that this technique could contribute to improved surgical outcomes.
Crisis of nitrogen nucleate boiling at high centrifugal acceleration fields
Authors: Zhukov V. E. , Klimov S. V. , Lutset M. O.
Published: January 2025

Discrepancies between experiment and the hydrodynamic theory of boiling crisis are discussed. Two exact solutions of the model problems are presented. It is shown that the additive model [B. I. Verkin, Yu. A. Kirichenko, and K. V. Rusanov, Heat Transfer during Boiling in Mass Force Fields of Various Intensities [in Russian], Naukova Dumka, Kiev (1988)] accounts for the phenomena observed.
Thermally-hydraulic flux instability analysis of low-temperature helium in a heated channel
Authors: Labuntsov D. A. , Mirzoyan P. A.
Published: January 2025

Analytical results of thermally-hydraulic flux instability of low-temperature helium in a heated channel are given in this report. The effect of pressure fluctuation power in the channel, friction law nonautomodality in the flux, and flux choking at the output valve are taken into consideration.
He II flow crisis in porous media
Authors: Shaposhnikov V. A. , Zotov N. V. , Grafov A. P.
Published: January 2025

The results of an experimental investigation of He II flow crisis in porous media are introduced. It is shown that one must know the structural characteristics of the porous media in order to predict the critical velocities of the He II superfluid component. Analysis of the effect of He II viscosity on flow through a porous medium shows that it is necessary to allow for the channel size dependence of the He II viscosity. The latter dependence and its usability limits are given.
Problems of superconductor coolant heat transfer
Authors: Lutset M. O.
Published: January 2025

A method of calculating nonstationary heat transfer is formulated based on the peculiarities concerning the dynamics of transition states of a superconductor with current. Examples of the method application are presented.
Numerical modeling of thermoinduced flows in the cooling channel of cryogenic systems
Authors: Babich V. I. , Pavlov Yu. M. , Churbanov V. V.
Published: January 2025

This paper deals with the computation of transient two-phase flows in the channels of cryogenic systems. The homogeneous equilibrium model was used for the description of the transient two-phase flow. The system of governing equations was solved on the basis of the explicit grid-characteristic differential scheme of the first order of accuracy. The program was tested by a comparison of the results of the computation with the analytical solution. An example of the computation is presented.
Program complex for thermomechanical design of cryostats on a personal computer
Authors: Zhitomirskii I. S. , Fenchenko V. N.
Published: January 2025

A program complex for thermomechanical design of cryostats based on a unique data representation of the designed construction is considered in this article. In this case, the optimal choice of the construction parameters can be made at the design calculation stage, and a calculation taking into account all interrelated factors which affect the construction is realized at the stage of mechanical, thermomechanical, and hydrodynamic check calculations. The complex operates on the basis of a developed menu using graphic methods. A hierarchical structure, represented by an oriented contour-free connected graph, is used to describe the construction effectively.
Composite superconductors coated with copper oxide to intensify heat transfer
Authors: Andrianov V. V. , Baev V. P. , Ipatov Yu. P. , Malyshenko S. P. , Muchnik R. G. , Rychagov A. V. , Sytnikov V. E. , Tomenko N. Ya.
Published: January 2025

A thin porous coating was used to increase the level of cryostatic stability of composite superconductors. Experimental investigations of the heat transfer to liquid helium and the physical properties of the porous coated superconductors were carried out. The optimal parameters of the porous coating were found.
Effect of tube diameter and duct cross-section shape on heat transfer during flow boiling of cryogenic fluids. Part 2: Nucleate boiling region
Authors: Baumann P. , Steiner D.
Published: January 2025

The experimental results for nucleate boiling of cryogenic and other fluids in vertical tubes show a significant influence of the tube diameter on the heat transfer coefficient. In addition, the wetting behavior of the duct must be known for horizontal tubes with circular and noncircular cross section. This is a complicated function of the cross section shape, the flow parameters, and the conditions of constant heat flux or constant wall temperature.
Stability experiment on the KfK poloidal field coil cable
Authors: Schmidt C. , Tateishi H.
Published: January 2025

A superconducting cable, developed for operation in poloidal field coils, was subjected to a stability test in fast changing magnetic fields. The test arrangement consists of a hairpin shaped closed loop of the cable, in which the transport current is induced. A pulse field is supplied to the sample by a capacitor discharge into a dipole magnet. The cooling conditions can be varied between liquid helium in a closed volume and supercritical helium. The results are discussed in terms of a stability model, which was successful in describing the stability of the basic strand. This model compares the energy input into the conductor during the field pulse with the transient heat removal capability of the coolant.
Effect of superfluid turbulence on nonstationary transcritical heat transport in He II
Authors: von Schwerdtner M. , Stamm G. , Fiszdon W.
Published: January 2025

The processes in He II initiated by a short but strong heat pulse are investigated experimentally in a rectangular channel of 2.6 × 2.6 cm2 cross section. The mechanism of heat transfer, based on internal convection, is strongly affected by the presence of superfluid vortex lines. When the input heat flux exceeds a certain limit, the counterflow velocity and hence the internal heat flux, is strongly reduced, which leads to a large increase of temperature in the region close to the heater. As is shown experimentally, this is correlated with the presence of a large amount of tangled superfluid vortex lines which are produced during the passage of the heat. The effect of pulse repetition is analyzed. A slight modification of Vinen’s equation for superfluid vortex line density (VLD) evolution gives a closer agreement with the experimental results.
Heat transfer in condensation pumping of 3He in dilution refrigerators
Authors: Sobolev V. I. , Sivokon’ V. E. , Pogorelov L. A. , Repin V. N. , Dotsenko V. V.
Published: January 2025

Heat transfer is studied in condensation pumps installed in a 3He–4He dilution refrigerator developed and put into operation at the Institute for Low Temperature Physics and Engineering, Academy of Sciences of the Ukrainian SSR. The calculations and experimental results show that this pump system can ensure sufficiently large circulations of 3He. A circulation rate of about 250 μmoles/s and a temperature of about 12 mK were obtained in the operating dilution refrigeration.
New planar SQUIDs based on niobium technology
Authors: Mück M. , Heiden C.
Published: January 2025

Two new SQUID variants have been made and tested using nanobridges as Josephson contacts. The first is a dc SQUID whose hysteretic weak links are inductively shunted such that it operates as a relaxation oscillator with a frequency depending on the applied magnetic flux. When standard ICs are used for FM detection, the readout electronics are cheap and compact, of the size of a matchbox. The second variant is a microwave-biased rf SQUID incorporated into a λ/2 stripline resonator, which is capacitively coupled to a coaxial cable leading to the room-temperature electronics. Peak-to-peak modulation voltages of several hundred μV were obtained in the investigated frequency range of 3 to 4.2 GHz. For both SQUID variants, white flux noise values of some 10−5Φ0/Hz1/2 have been found.
Methods of analytical control for high-T
c superconducting materials
Authors: Blank A. B. , Babich G. A. , Glushkova L. V. , Zolotovitskaya E. S. , Kotok I. A. , Lebed N. B. , Mogilko E. T. , Mirenskaya I. I. , Nartova Z. M. , Pantaler R. P. , Potapova V. G. , Pulyaeva I. V. , Filippovich L. I. , Shtitel’man Z. V. , Shevtsov N. I. , Eksperiandova L. P.
Published: January 2025

Methods of analytical control of initial powders, ceramics, films, and single crystals have been worked out for the chemical diagnostics of the high-Tc superconductors Y(Re)–Ba–Cu–O, Bi–Ca–Sr– Cu–O, Bi–Pb–Ca–Sr–Cu–O, and Tl–Ca–Ba–Cu–O: the molar ratio methods of element determination in powders and ceramics and also in films and single crystals up to 2-5 μg, methods of determination in powder and ceramics of active oxygen, valence state of variable-valence elements (Cu, Bi, Tl), and determination of impurities such as H2O,Co32−, organic carbon, S, N, Cl, Na, K, Mg, Ca, Sr, Al, Si, Pb, V, Mo, Cr, Sn, Bi, Mn, Fe, Co, and Ni. The methods studied are applied to the optimization of solid-phase synthesis and hot pressing of high-Tc superconductors, estimation of their purity level, and for assessment of their chemical degradation.
High-T
c superconductivity of Bi and Tl mixed-valence Cu oxides
Authors: Politis O.
Published: January 2025

High-temperature superconductivity above the nitrogen boiling temperature has already been observed in Re–Ba–Cu–O systems (Re: rare-earths). The discovery of high-temperature superconductivity in ceramic compounds without rate-earth elements has opened the door for many new high-Tc compounds with still higher stable and reproducible Tc, as have been found recently in rare-earth mixed-valence copper oxides. We report here the constitution, characterization, and superconducting temperatures of bulk superconductors in the systems Bi–Sr–Ca–Cu–O and Tl–Ca–Ba–Cu–O. We have achieved zero resistance at temperatures exceeding 100 K by adding Pb to the Bi–Sr–Ca–Cu–O system. The highest value we have observed is Tc,zero = 107 K for Bi1.8Pb0.2Ca2Sr2Cu3O10. In multiphase samples with the nominal composition of Tl2Ca2Ba2Cu3O10 and TlCa3BaCu3O9, zero resistivity at 122 and 217 K have been found.

Further substitution of Bi (or Pb) by Sb could apparently increase Tc to a value as high as 134 K. We have attempted such a substitution with a variety of compositions around the Bi2–x Pbx Ca2Sr2Cu3O10 phase, as well as different heat treatments in which the rate of heating, final temperatures, atmospheres, periods of time in the oven, and cooling rates were varied. The results of such an attempt are presented.
Nonlinear effects in thin Sb films
Authors: Butenko A. V. , Bukhshtab E. I. , Kashirin V. Yu.
Published: January 2025

Quantum corrections to the resistance of thin Sb films are measured for various measuring currents. The magnitude of quantum corrections is found to be dependent on the Joule heating of the sample and the electron gas superheating which can be observed in disordered films due to high values of inelastic scattering time as compared to the transport relaxation time.
Cooperative phase coherence of bremsstrahlung in the resistive state of superconducting films
Authors: Gogadze G. A.
Published: January 2025

A microscopic theory of inelastic processes of quasiparticle scattering at the phase boundary of a phase slip center with photon emission is developed. Phase coherence of collective bremsstrahlung due to spontaneous synchronization of individual emitters interacting through radiation field is proved.
Critical current of high-T
c ceramics
Authors: Dmitriev V. M. , Khristenko E. V. , Prikhod’ko O. R.
Published: January 2025

Critical currents are measured on samples of the high-Tc superconducting compound TlCa2Ba3Cu4Oy in the temperature range 4.2 to Tc and external magnetic field up to 1.3 T. The results obtained are interpreted based on a model treating the ceramic sample as a set of superconducting grains electrically coupled through Josephson weak links, whose sizes obey the normal distribution law. It is shown that the dependences of critical currents on the magnetic field strength in HTS ceramics are determined mainly by the characteristics of weak links of various sizes, by the availability of structural fluctuations, and by the nonuniform current distribution over the link sections.
Transfer of sound by electrons upon multichannel reflection of charge carriers by a metal surface
Authors: Ivanovski G. , Kirichenko O. V. , Peschanskii V. G.
Published: January 2025

The role of conduction electrons in acoustic signal transfer is studied theoretically for conductors with a smooth surface. It is shown that the existence of a few nonequivalent states for a specularly reflected electron leads to the generation of anomalous waves which are not observed in samples with a very rough surface. These waves are formed by electrons from the neighborhoods of points on the Fermi surface, where an additional channel of specular reflection is involved, and propagate at a velocity considerably exceeding the velocity of the main acoustic signal.
Magnetic properties of U2Zn17 compound
Authors: Panfilov A. S. , Svechkarev I. V. , Smirnov A. I. , Diko P. , Mihalik M. , Tima T. , Zentko A.
Published: January 2025

The magnetic susceptibility of the heavy-fermion compound U2Zn17 is measured in magnetic fields 0.5 mT–1 T in the temperature range 1.7–300 K. The values of the parameters of the modified Curie–Weiss law, which is obeyed by the susceptibility at T ≥ 40 K, are refined. There is no temperature independent contribution, and the effective magnetic moment of a U ion is equal to 3.2±0.05 μB. No traces are observed of the superconductivity caused by deviations from stoichiometry and the existence of accompanying phases. The known low-temperature characteristic features of the susceptibility can be attributed to antiferromagnetic ordering in U2Zn17 at T ≃ 10 K.
Emission from a doped crystal with structural changes under pulse heating of the sample
Authors: Gorobchenko V. S. , Eremenko V. V. , Ogurtsova L. A.
Published: January 2025

The parameters of radiation emitted by an anthracene-doped biphenyl crystal are studied in the temperature range from 5.5 to 40 K at different densities of excitation power W by the third harmonic of an Nd laser. The doublet structure of the induced emission spectum is attributed to the emission from commensurate and incommensurate phases of the crystal. The anomalous behavior of the frequency interval Δν between the doublet lines is explained by structural changes of the matrix in the region of the incommensurate phase II. A decrease in Δν upon an increase in W is associated with sample heating. The specific heat of the crystal under investigation is determined experimentally with a laser excitation under the assumption of thermodynamic equilibrium. The difference between the obtained value of heat capacity and the one measured calorimetrically is explained by using the hypothesis of generation of excess phonons upon laser excitation due to peculiarities of relaxation processes (or the “phonon bottleneck” type).
Heat capacity of dilute solid solutions of 14N2 and 15N2 in Kr at helium temperatures
Authors: Muromtsev P. I. , Bagatskii M. I. , Manzhelii V. G. , Minchina I. Ya. , Krivchikov A. I.
Published: January 2025

The heat capacity of dilute solid solutions of l4Ne2 and l5N2 with impurity concentrations n = 0.125 and 0.25 mol. % in krypton is measured in the temperature range 0.5–6 K. The impurity components of the solid solutions are compared with those predicted by the Devonshire–Manz–Mirsky (DMM) model which assumes an instantaneous spatial adjustment of surrounding atoms to a rotating impurity molecule. It is shown that the above model provides a satisfactory explanation for the experimental data for T < 2 K. The energy spectrum of the rotational motion of impurity molecules is proposed, providing an agreement between the experimental and theoretical data.
Symmetry analysis of the structural phase transition in KDy(MoO4)2
Authors: Vitebskii I. M. , Zherlitsyn S. V. , Stepanov A. A. , Fil’ V. D.
Published: January 2025

Symmetry analysis of the structural phase transition in KDy(MoO4)2 caused by the cooperative Jahn–Teller effect is carried out. Assuming the phase transition in KDy(MoO4)2 to be of second order, it is concluded that the spatial group of the dissymmetric phase is C2h5. It is shown that a long-periodic incommensurate structure must be induced under the action of an electric field in the vicinity of Tc, while an transition. The behavior of the elastic characteristics is studied experimentally in the region of the structural phase transition in an external magnetic field.
Interaction of spin waves with ferroelectric domain wall excitations in a ferroelectromagnetic material
Authors: Manzhos I. V. , Chupis I. E.
Published: January 2025

A strengthening of the dynamic magnetoelectric bond in a magnetoelectric material with a ferroelectric domain wall (FE DW) is predicted. It is shown that FE DW induces a localized spin state with an energy near the bottom of the magnetic band. The generation of spin waves by FE DW oscillations is investigated in a varying uniform electric field.
Effect of oxygen deficit on the magnetic properties of weak bonds in YBa2Cu3O7–x polycrystals
Authors: Elesin V. F. , Sinchenko A. A.
Published: January 2025

Dependence of the magnetization M of polycrystalline samples of YBa2Cu3O7–x. on weak magnetic fields (H ≪ Hc1) have been obtained for various oxygen concentrations (0.10 ≤ x ≤ 0.53). An analysis of these dependences points towards the Josephson mechanism of conductivity between ceramic granules. A nonmonotonic variation of the magnetic susceptibility of superconducting granules is observed with increasing x. Such a variation correlates with a change in the critical temperature corresponding to the onset of superconducting transition.
Quantitative behavior of the intermediate state of a current-carrying cylinder. Choice of the theory
Authors: Frolov V. A.
Published: January 2025

The basic structural parameters of the intermediate state produced by a current passing through a monocrystalline cylinder are measured as functions of the current. A good qualitative agreement is reached between the experiment and the London–Andreev theory.
Temperature dependence of ultrasound attenuation in normal metals
Authors: Vasil’ev A. N. , Gaidukov Yu. P. , Popova E. A. , Georgius R. Sh.
Published: January 2025

Temperature dependence of attenuation of longitudinal and transverse acoustic waves in indium, tin, and lead single crystals are investigated by a contactless technique in the 4–500 K temperature range. Sound attenuation is determined from resonance parameters of standing elastic waves excited by electromagnetic waves in plane-parallel metal plates. The observed dependences are essentially nonmonotonic. In the case of indium, they are characterized by blurred “high-temperature” and “low-temperature” attenuation peaks. The latter are shifted towards higher temperatures with increasing frequency. “Low-temperature” peaks are also observed in Sn and Pb, the attenuation in these metals increasing at high temperatures. The contributions of different dissipation mechanisms, including sound scattering by electrons, phonons, dislocations, and point defects, to the temperature dependence of sound attenuation are estimated.
Rapid depolarization of muons in condensed nitrogen
Authors: Grebinnik V. G. , Duginov V. N. , Zhukov V. A. , Kirillov B. F. , Lazarev A. B. , Nikol’skii B. A. , Pirogov A. V. , Storchak V. G. , Shilov S. N.
Published: January 2025

Temperature dependences of muon precession parameters are measured in the temperature interval from 10 to 68 K in liquid and crystalline nitrogen with an oxygen concentration of 10−6. It is proved experimentally that oxygen impurities are not responsible for the rapid depolarization of muons in condensed nitrogen.
On the phase separation and phase diagrams of solid hydrogen solutions
Authors: Prokhvatilov A. I.
Published: January 2025

Results of theoretical and experimental studies of binary hydrogen solutions are analyzed. It is suggested that in systems containing a considerable amount of molecules with a rotational moment J = 1, a separation of the solid solution into isomorphic phases with different rotational states of the molecules must be observed. Taking this circumstance into consideration, typical phase equilibrium diagrams are proposed for binary hydrogen systems. The p-H2-o-H2 phase diagram is used to describe the nature of high-temperature phase transformation in normal crystalline hydrogen and the phase separation in the system n-H2-n-D2.
The Aharonov–Bohm effect in narrow-band semiconductors
Authors: Bogachek É. N.
Published: January 2025

The Aharonov–Bohm effect is investigated in nonsingly connected semiconductors. The effect is manifested in the oscillating dependence of the magnetic moment (as well as persistent current) having the fundamental period hc/e and caused by the polarization of electrons in the valence band by the vector potential field.
The Aharonov–Bohm effect in a Hubbard chain
Authors: Zvyagin A. A.
Published: January 2025

The Aharonov–Bohm effect in a Hubbard chain is investigated theoretically.
Dependence of the parametric instability threshold of spin waves on the type of relaxation
Authors: Zvyagin A. A. , Sadaui Yu. , Tsukernik V. M.
Published: January 2025

The dependence of the threshold field of the parametric instability in a system of spin waves on the Landau-Lifshitz relaxation constant is obtained and analyzed.
Point-contact studies of semiconductor PbTe–PbS superconducting superlattice as a model of HTS
Authors: Bobrov N. I. , Rybal’chenko L. F. , Fisun V. V. , Yanson I. K. , Mironov O. A. , Chistyakov S. V. , Zorchenko V. V. , Sipatov A. Yu. , Fedorenko A. I.
Published: January 2025

Superconducting (SC) superlattices (SL) of the epitaxial semiconductor PbTe–PbS/(001) KCl with two-dimensional ordered misfit dislocation (MD) networks across heteroboundaries (HB) are studied, and the obtained results are compared with the corresponding data for YBaCuO. An analysis of the fluctuational region showed that the pairing of electrons in SL takes place at the sites of dislocation networks. In the region of SC fluctuations, the IVC derivatives of point-contacts (PC) based on SL and HTS display a metal-insulator transition associated with delocalization of carriers from the vicinity of the structural elements responsible for the emergence of SC. The critical current density in a superlattice is determined, and a mechanism is proposed for formation of excess current on the IVC of PC based on SL and HTS. The values of the energy gap Δ0 at low temperatures in units of kTc are found to be anomalously large for SL and HTS. For anisotropic three-dimensional SL with a strong bond between two-dimensional SC planes, two gaps emerge from the MD. For quasi-two-dimensional SL with a weak bond between two-dimensional SC planes, the Δ(T) dependence is nonmonotonic, and the fluctuation region for these SL and for HTS reveals a gap that is practically independent of temperature. The IVC derivatives of a Cu–SL PC reveal an oscillating structure which is restricted to an energy of 90 meV and is apparently associated with the electron–phonon interaction. It is assumed that there is a similarity between the SC mechanisms in SL and HTS.
Stress release-induced piezoresponse in lead-free piezoceramics with high-symmetry morphotropic phase boundary
Authors: Vendrell Xavier , Rubio-Marcos Fernando , del Campo Adolfo , Mestres Lourdes , Garcia Jose E.
Published: January 2025

The (1 − x)(Bi0.5Na0.5)TiO3-xBaTiO3 (BNT-BT) system has attracted a great deal of interest because it presents a morphotropic phase boundary (MPB) between the rhombohedral and tetragonal phases for 0.05 < x < 0.08. Identifying the MPB in the BNT-BT system often results in materials exhibiting a high-symmetry (pseudo)cubic x-ray diffraction pattern. However, this singular composition exhibits ferroelectricity, which has been explained as a consequence of a field-induce phase transformation. Here, we demonstrate that the stress release after poling, from the virgin state of the sample, is a crucial phenomenon to obtain piezoelectric response in MPB BNT-BT. The mechanism behind the unusual poling–depoling process in piezoceramics exhibiting high-symmetry MPB is elucidated by combining x-ray diffraction measurements and advanced Raman spectroscopy. This underscores the importance of post-poling stress release from the virgin state as a critical factor in attaining piezoelectric response in lead-free piezoceramics with high-symmetry MPB configurations.
The Kumaraswamy modified Kies-G family of distributions: properties and applications
Authors: S S Swetha Potluri , Nagarjuna Vasili B V
Published: January 2025

The development of new families of distributions is crucial for addressing the increasing demand for flexible models capable of managing complicated datasets. This paper introduces a new three-parameter family of distributions named the Kumaraswamy Modified Kies-G family, which accommodates complex and skewed data. The new model offers greater flexibility, particularly in its tail behaviour, making it suitable for accurately fitting skewed datasets. We examine the statistical properties of the proposed model and an extension of the exponential distribution is added, to showcase its versatility. Through the simulation, performance of the parameter estimates is evaluated. The real data applications reveal that proposed model performs better than its competing four-parameter models based on various goodness-of-fit and adequacy measures.