Mass Separation Research Articles

Diffusion in nanoporous materials with special consideration of the measurement of determining parameters (IUPAC Technical Report)

Abstract The random motion (the diffusion) of guest molecules in nanoporous host materials is key to their manifold technological applications and, simultaneously, a ubiquitous phenomenon in nature quite in general. Based on a specification of the different conditions under which molecular diffusion in nanoporous materials may occur and of the thus resulting relevant parameters, a survey of the various ways of the measurement of the determining parameters is given. Starting with a condensed introduction to the respective measuring principles, the survey notably includes a summary of the various parameters accessible by each individual technique, jointly with an overview of their strengths and weaknesses as well as of the respective ranges of observation. The presentation is complemented by basic relations of diffusion theory and molecular modeling in nanoporous materials, illustrating their significance for enhancing the informative value of each measuring technique and the added value attainable by their combination. By providing guidelines for the measurement and reporting of diffusion properties of chemical compounds in nanopores, the document aims to contribute to the clarification and standardization of the presentation, nomenclature, and methodology associated with the documentation of diffusion phenomena in nanoporous materials serving for catalytic, mass separation, and other relevant purposes.

Production and purification of molecular 225Ac at CERN-ISOLDE

AbstractThe radioactive nuclide 225Ac is one of the few promising candidates for cancer treatment by targeted-$$\alpha$$ α -therapy, but worldwide production of 225Ac faces significant limitations. In this work, the Isotope Separation On-Line method was used to produce actinium by irradiating targets made of uranium carbide and thorium carbide with 1.4-GeV protons. Actinium fluoride molecules were formed, ionized through electron impact, then extracted and mass-separated as a beam of molecular ions. The composition of the mass-selected ion beam was verified using time-of-flight mass spectrometry, $$\alpha$$ α - and $$\gamma$$ γ -ray decay spectrometry. Extracted quantities of $$^{225}\textrm{Ac}^{19}\textrm{F}_2^{+}$$ 225 Ac 19 F 2 + particles per $$\upmu$$ μ C of incident protons were $$3.9(3)\times 10^7$$ 3.9 ( 3 ) × 10 7 from a uranium carbide target and $$4.3(4)\times 10^7$$ 4.3 ( 4 ) × 10 7 for a thorium carbide target. Using a magnetic mass separator, the long-lived contamination 227 Ac is suppressed to $$<5.47\times 10^{-7}$$ < 5.47 × 10 - 7 (95% confidence interval) with respect to 225Ac by activity. Measured rates scale to collections of 108 kBq$$\upmu$$ μ A$$^{-1}$$ - 1 h$$^{-1}$$ - 1 of directly produced $$^{225}\textrm{Ac}^{19}\textrm{F}_2^{+}$$ 225 Ac 19 F 2 + .

Emerging Advances around Nanofluidic Transport and Mass Separation under Confinement in Atomically Thin Nanoporous Graphene.

Membrane separation stands as an environmentally friendly, high permeance and selectivity, low energy demand process that deserves scientific investigation and industrialization. To address intensive demand, seeking appropriate membrane materials to surpass trade-off between permeability and selectivity and improve stability is on the schedule. 2Dmaterials offer transformational opportunities and a revolutionary platform for researching membrane separation process. Especially, the atomically thin graphene with controllable porosity and structure, as well as unique properties, is widely considered as a candidate for membrane materials aiming to provide extreme stability, exponentially large selectivity combined with high permeability. Currently, it has shown promising opportunities to develop separation membranes to tackle bottlenecks of traditional membranes, and it has been of great interest for tremendously versatile applications such as separation, energy harvesting, and sensing. In this review, starting from transport mechanisms of separation, the material selection bank is narrowed down to nanoporous graphene. The study presents an enlightening overview of very recent developments in the preparation of atomically thin nanoporous graphene and correlates surface properties of such 2D nanoporous materials to their performance in critical separation applications. Finally, challenges related to modulation and manufacturing as well as potential avenues for performance improvements are also pointed out.

Impact of Asymmetric Microstructure on Ion Transport in Ti3C2Tx Membranes.

Consolidation or densification of low-dimensional MXene materials into membranes can result in the formation of asymmetric membrane structures. Nanostructural (short-range) and microstructural (long-range) heterogeneity can influence mass transport and separation mechanisms. Short-range structural dynamics include the presence of water confined between the 2D layers, while long-range structural properties include the formation of defects, micropores, and mesopores. Herein, it is demonstrated that structural heterogeneity in Ti3C2Tx membranes fabricated via vacuum-assisted filtration significantly affects ion transport. Higher ion permeabilities are achieved when the dense "bottom" side of the membrane, rather than the porous "top" side, faces the feed solution. Characterization of the membrane reveals distinct differences in flake alignment, surface roughness, and porosity across the membrane. The directional dependence on permeability suggests that one region of the membrane experiences stronger internal concentration polarization, potentially suppressing permeability through the porous side of the membrane.

C1-ring оsteosynthesis as a functionally preserving operation for unstable atlas fractures

Objective. To analyze the dynamics of pain syndrome, quality of life and functional status of patients with unstable atlas fractures after C1-ring osteosynthesis.Material and Methods. Study design: observational retrospective case series study (n = 15). The intensity of pain syndrome was assessed using the VAS scale before surgery, 3 days, and 3 and 6 months after surgery. The quality of life was assessed using the Neck Disability Index (NDI) before surgery, and 3 and 6 months after surgery. Functional status, as well as cervical spine range of motion (head turn left/right, flexion/extension) was assessed 3 and 6 months after surgery. The integrity of the atlas bone ring and the degree of fusion after fixation were assessed using axial CT scans; and the lateral mass separation was assessed using frontal CT scans. The criterion for transverse ligament injury was a separation of lateral masses of more than 8.1 mm. Results. All patients had C1 fractures type 3B according to Gehweiler, out of them 7 patients (46.7 %) had traumatic injury to the atlas transverse ligament according to Dickman type 1, and 8 patients (53.3 according to Dickman type 2. The average age of patients was 40 years (12; 71), the male/female ratio was 2/1. In 7 patients (46.7 %), the cause of injury was diving, in 6 (40.0 %) it was a traffic accident, and in 2 (13.3 %) – a fall from a standing height. Observation of patients revealed a positive dynamics in the form of statistically significant regression of pain according to VAS before and 6 months after surgery from 6.8 (6.0; 8.0) to 1.0 (1.0; 0.0) points (Z = -3.434; p = 0.001). A positive trend was also noted in the form of a decrease in NDI scores and an improvement in the quality of life after 3 (Z = -3.411; p = 0.001) and 6 months after surgery (Z = -3.410; p = 0.001). The range of motion (turn left/right, flexion/extension) increased statistically significantly by the 6th month after C1-ring osteosynthesis, and its indicators were close to physiological ones. Postoperative CT scans showed positive dynamics in the form of statistically significant regression of the lateral mass separation from 10.4 mm (8.9; 11.4) to 2.2 mm (1.8; 2.6); Z = -3.408; p = 0.001. Complete fusion of the atlas fracture was observed after 12.5 months (8.5; 16.5).Conclusion. Isolated posterior osteosynthesis of the atlas ring for Gehweiler type 3B injury using a repositioning compression maneuver under distraction conditions is physiologically justified. It is a reliable method of stabilization, ensures the restoration of congruence and the entire range of motion in the atlanto-occipital and atlantoaxial joints and stability of the occipital-atlantoaxial complex. This operation contributes to a considerable and long-term reduction in the intensity of pain syndrome and a significant improvement in the quality of life.

Writing with Mass-Selected Ions Using a Dynamic Field Wien Filter.

We have designed and constructed a low-cost Wien filter based on strong permanent magnets and integrated it into an ion soft-landing instrument to enable parallel deposition as well as one- and two-dimensional surface patterning of mass-selected ions using dynamic fields. We show the capabilities of this device for separating ions from a multicomponent high-flux continuous ion beam and simultaneous deposition of ions of different mass-to-charge ratios onto discrete locations on a surface. When a dynamic electric field is applied parallel to the magnetic field, ions are deposited in one-dimensional arrays, laterally separated by mass. The field's strength, frequency, and waveform type determine both the lengths of the arrays and the density of ions across the 1-D pattern. Additionally, a second dynamic field from user-defined waveforms orthogonal to the magnetic field enables two-dimensional surface patterning of ions while maintaining mass separation. These experiments demonstrate the practical utility of a Wien filter for the controlled fabrication of interfaces with arbitrary patterns of mass-selected ions.

Decay of a microsecond seniority 3 isomeric state in Hf155

Excited states in the neutron-deficient nuclide Hf155 have been investigated in experiments performed at the Accelerator Laboratory of the University of Jyväskylä. The Hf155 nuclei were produced in fusion-evaporation reactions induced by beams of 295 and 315 MeV Ni58 ions bombarding an isotopically enriched Pd102 target and separated using the recoil mass separator MARA. An isomeric state having a half-life of 510(30) ns was discovered and is interpreted as a seniority υ=3, (πh11/22⊗νf7/2)27/2− configuration. The γ-ray transitions emitted in the deexcitation of the isomeric state to the ground state were identified and a level scheme was constructed, from which the excitation energy of the isomer was determined to be 2581.5(10) keV. A B(E2) value of 0.45(3) W.u. was deduced for the 105.4 keV transition depopulating the isomeric state. The deduced level scheme and B(E2) value are compared with systematics and shell-model calculations. Published by the American Physical Society 2024

A New Parameterization for Finding Solutions for Microlensing Exoplanet Light Curves

The gravitational microlensing method of discovering exoplanets and multi-star systems can produce degenerate solutions, some of which require in-depth analysis to uncover. We propose a new parameter space that can be used to sample potential solutions more efficiently and is more robust at finding all degenerate solutions for the “central-resonant” caustic degeneracy. We identified two new parameters, k and h, that can be sampled in place of the mass ratios and separations of the systems under analysis to identify degenerate solutions. The parameter k is related to the size of the central caustic, Δξ c , while h is related to the distance of a point along the k contour from log(s) = 0, where s is the projected planet-host separation. In this work, we present the characteristics of these parameters and the tests we conducted to prove their efficacy.

Plasma centrifugation method for separation of the nuclear waste

The high-throughput, plasma-based, mass separation techniques of nuclear waste are still an active research topic due to the theoretical and practical complexity of processing such waste. The nuclear waste can be separated according to its masses by plasma centrifugation technique. Because of this, the present research has been performed by setting up E → × B → rotation in cold cylindrical plasma surrounded by an ideally conducting homogenous shell inside a plasma centrifuge device. The results obtained are useful in analyzing the magneto-rotational instability (MRI) and trajectories of the plasma particles which are beneficial for improving the throughput and separation factor of the device.

AI-based automated segmentation for ovarian/adnexal masses and their internal components on ultrasound imaging.

Segmentation of ovarian/adnexal masses from surrounding tissue on ultrasound images is a challenging task. The separation of masses into different components may also be important for radiomic feature extraction. Our study aimed to develop an artificial intelligence-based automatic segmentation method for transvaginal ultrasound images that (1)outlines the exterior boundary of adnexal masses and (2)separates internal components. A retrospective ultrasound imaging database of adnexal masses was reviewed for exclusion criteria at the patient, mass, and image levels, with one image per mass. The resulting 54 adnexal masses (36 benign/18 malignant) from 53 patients were separated by patient into training (26 benign/12 malignant) and independent test (10 benign/6 malignant) sets. U-net segmentation performance on test images compared to expert detailed outlines was measured using the Dice similarity coefficient (DSC) and the ratio of the Hausdorff distance to the effective diameter of the outline ( ) for each mass. Subsequently, in discovery mode, a two-level fuzzy c-means (FCM) unsupervised clustering approach was used to separate the pixels within masses belonging to hypoechoic or hyperechoic components. The DSC (median [95% confidence interval]) was 0.91 [0.78, 0.96], and was 0.04 [0.01, 0.12], indicating strong agreement with expert outlines. Clinical review of the internal separation of masses into echogenic components demonstrated a strong association with mass characteristics. A combined U-net and FCM algorithm for automatic segmentation of adnexal masses and their internal components achieved excellent results compared with expert outlines and review, supporting future radiomic feature-based classification of the masses by components.

Towards a precise measurement of 157Tb nuclear decay data: Sample purification using resonance ionization mass spectrometry

In nuclear physics, 157Tb emerges as a prime candidate for experiments aimed at elucidating neutrino mass constraints and at searching for sterile neutrinos. Despite its importance, 157Tb exhibits highly uncertain values for its nuclear decay properties. A significant challenge in many efforts to measure such data lies in the simultaneous undesired presence of 158Tb in the samples, which hinders precise activity determination. Mass separation emerges as a crucial method for obtaining pure 157Tb specimens. This work outlines the production of an isotopically-pure 157Tb sample through mass separation and ion implantation, using the RISIKO facility at the University of Mainz. The initial material was obtained from proton-irradiated Ta samples through radiochemical separation at the Paul Scherrer Institute. In total, a sample containing 8.7(9) · 1012 atoms of 157Tb was obtained. The efficiency of the mass separation and ion implantation was 13(2) %. The purified material served as the basis for new research endeavors at the Physikalisch Technische Bundesanstalt Braunschweig aiming at the determination of nuclear data for 157Tb with significantly improved precision.

Increased Auditory Dual Task Cost During Gait Initiation in Adult Patients With Persistent Concussion Symptoms

ObjectiveTo compare dual task cost (DTC) during gait initiation (GI) between a population of patients with persistent concussion symptoms (PCS) and age-matched healthy participants. DesignCohort study. SettingUniversity research center. ParticipantsA cohort sample including 15 participants with PCS (43.9±11.7y, 73.3% female) and 23 age-matched healthy participants (42.1±10.3y, 65.2% female) as controls. InterventionsParticipants were tested on a single occasion where they performed 5 trials of single task and 5 trials of dual task GI with 12-camera motion capture and 3 force plates. Main Outcome MeasuresThe dependent variables of interest were the DTC for the center of pressure (COP) displacement and velocity during the anticipatory postural adjustment (APA) phase, the COP-center of mass (COP-COM) separation, and the response accuracy during the auditory cognitive tasks. ResultsThere were significant group differences with worse DTC for the PCS participants in anterior (A)/posterior (P) displacement (PCS, −37.5±22.1%; Control, −9.7±39.2%; P=.016, d=0.874), APA medial (M)/lateral (L) velocity (PCS, −34.8±28.8%; Control, −17.0±40.21%; P=.041, d=0.866), and the peak COP-COM separation (PCS, −7.3±6.7%; Control, 0.6±6.5%; P=.023, d=1.200). There were no significant group differences in the APA A/P velocity (PCS, −38.8±33.1%; Control, −19.8±43.9%; P=.094), APA M/L displacement (PCS, −34.8±21.8%; Control, −10.6±25.3%; P=.313), or cognitive task performance (PCS, −2.7±10.8%; Control, −0.2±4.3%; P=.321). ConclusionsPCS participants had greater (worse) DTC during both the planning and execution of the task, with large effect sizes (d>0.80). PCS participants also used a posture-second strategy whereby attentional resources were inappropriately allocated to the cognitive task. These deficits may challenge a patient's ability to complete activities of daily living and limit their functional independence.

Fate of supernova progenitors in massive binary systems

ABSTRACT How massive stars end their lives depends on the core mass, core angular momentum, and hydrogen envelopes at death. However, these key physical facets of stellar evolution can be severely affected by binary interactions. In turn, the effectiveness of binary interactions itself varies greatly depending on the initial conditions of the binaries, making the situation much more complex. We investigate systematically how binary interactions influence core–collapse progenitors and their fates. Binary evolution simulations are performed to survey the parameter space of supernova progenitors in solar metallicity binary systems and to delineate major evolutionary paths. We first study fixed binary mass ratios ($q=M_2/M_1$ = 0.5, 0.7, and 0.9) to elucidate the impacts of initial mass and initial separation on the outcomes, treating separately Type Ibc supernova, Type II supernova, accretion-induced collapse (AIC), rapidly rotating supernova (Ibc-R), black hole formation, and long gamma ray burst (long GRB). We then conduct 12 binary population synthesis model calculations, varying the initial condition distributions and binary evolution parameters, to estimate various supernova fractions. We obtain a Milky Way supernova rate $R_{\rm SN} = (1.78$–$2.47) \times 10^{-2} \, {\rm yr}^{-1}$ which is consistent with observations. We find the rates of AIC, Ibc-R, and long GRB to be $\sim 1/100$ the rate of regular supernovae. Our estimated long GRB rates are higher than the observed long GRB rate and close to the low luminosity GRB rate, although care must be taken considering our models are computed with solar metallicity. Furthering binary modelling and improving the inputs one by one will enable more detailed studies of these and other transients associated with massive stars.

Plastic Quantification and Polyethylene Overestimation in Agricultural Soil Using Large-Volume Pyrolysis and TD-GC-MS/MS.

Quantification of microplastics in soil is needed to understand their impact and fate in agricultural areas. Often, low sample volume and removal of organic matter (OM) limit representative quantification. We present a method which allows simultaneous quantification of microplastics in homogenized, large environmental samples (>1 g) and tested polyethylene (PE), polyethylene terephthalate (PET), and polystyrene (PS) (200-400 μm) overestimation by fresh and diagenetically altered OM in agricultural soils using a new combination of large-volume pyrolysis adsorption with thermal desorption-gas chromatography-tandem mass spectrometry (TD-GC-MS/MS). Characteristic MS/MS profiles for PE, PET, and PS were derived from plastic pyrolysis and allowed for a new mass separation of PET. Volume-defined standard particles (125 × 125 × 20 μm3) were developed with the respective weight (PE: 0.48 ± 0.12, PET: 0.50 ± 0.10, PS: 0.31 ± 0.08 μg), which can be spiked into solid samples. Diagenetically altered OM contained compounds that could be incorrectly identified as PE and suggest a mathematical correction to account for OM contribution. With a standard addition method, we quantified PS, PET, and PEcorrected in two agricultural soils. This provides a base to simultaneously quantify a variety of microplastics in many environmental matrices and agricultural soil.

Novel strategy for efficient energy recovery and pollutant control from sewage sludge and food waste treatment

Considering the high organic matter contents and pollutants in sewage sludge (SS) and food waste (FW), seeking green and effective technology for energy recovery and pollutant control is a big challenge. In this study, we proposed a integrated technology combing SS mass separation by hydrothermal pretreatment, methane production from co-digestion of hydrothermally treated sewage sludge (HSS) centrate and FW, and biochar production from co-pyrolysis of HSS cake and digestate with heavy metal immobilization for synergistic utilization of SS and FW. The results showed that the co-digestion of HSS centrate with FW reduced the NH4+-N concentration and promoted volatile fatty acids conversion, leading to a more robust anaerobic system for better methane generation. Among the co-pyrolysis of HSS cake and digestate, digestate addition improved biochar quality with heavy metals immobilization and toxicity reduction. Following the lab-scale investigation, the pilot-scale verification was successfully performed (except the co-digestion process). The mass and energy balance revealed that the produced methane could supply the whole energy consumption of the integrated system with 26.2 t biochar generation for treating 300 t SS and 120 t FW. This study presents a new strategy and technology validation for synergistic treatment of SS and FW with resource recovery and pollutants control.

High-resolution laser spectroscopy on the hyperfine structure and isotope shift of 237,239\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^{237,239}$$\\end{document}Np

Nuclear ground state properties of 237,239\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^{237,239}$$\\end{document}Np were investigated by high-resolution laser spectroscopy at the RISIKO mass separator off-line radioactive beam facility of the University of Mainz. The isotope shifts and the hyperfine parameters were determined in two different atomic ground-state transitions at 398.80 nm and 395.61 nm. The data allowed for calculation of the so far unknown nuclear moments of the short-lived isotope 239\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^{239}$$\\end{document}Np, i.e. the nuclear magnetic dipole moment of μI\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\mu _I$$\\end{document} = +3.18(2) μN\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\mu _N$$\\end{document} and the electric quadrupole moment of QS\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$Q_S$$\\end{document} = +4.05(8) eb, using the known nuclear moments of 237\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^{237}$$\\end{document}Np as a reference, which were determined by electron paramagnetic resonance and investigations of muonic X-ray hyperfine structures, respectively.

Determination of the activity and nuclear decay data of 157Tb

Terbium-157 was radiochemically extracted from an irradiated tantalum target. Since the resulting material contained a significant impurity of 158Tb, 157Tb was isotopically purified using laser resonance ionization at the RISIKO mass separator in Mainz and then implanted on an aluminum (Al) foil. The implanted 157Tb was measured by two different calibrated gamma-ray spectrometers to determine photon emission rates. After dissolving the Al foil, a high purity 157Tb solution was obtained. The corresponding activity concentration was determined with a low relative uncertainty of 0.52% through a combination of liquid scintillation counting using the TDCR method and 4π(X,e)(LS)-(X,γ)(CeBr3) coincidence counting. By combining the results from all measurement techniques, emission intensities for K X-rays and gamma-rays were derived and found to be 16.05(31)% and 0.0064(2)%, respectively. The probability for K electron capture of the first forbidden non-unique transition to the ground state was determined to be 17.16(35)%. The probabilities for the electron-capture branch to the excited level and the ground state were found to be 0.084(4)% and 99.916(4)%, respectively. A Q+ value of 60.23(18) keV was estimated based on simplified BetaShape calculations, assuming an allowed transition.

Effectiveness analysis of double EndoButton suture fixation Latarjet procedure for treatment of anterior shoulder dislocation with glenoid bone defect caused by military training injuries

To investigate the effectiveness of double EndoButton suture fixation Latarjet procedure in the treatment of shoulder anterior dislocation with glenoid bone defect caused by military training injuries. The clinical data of 14 patients with anterior shoulder dislocation with glenoid bone defect due to military training injuries who met the selection criteria and admitted between August 2021 and December 2022 were retrospectively analyzed. All patients were male, the age ranged from 21 to 38 years, with an average of 26.8 years. The time from initial dislocation to operation was 6-15 months, with an average of 10.2 months. Anterior shoulder dislocation occurred 5-12 times, with an average of 8.2 times. All glenoid bone defects were more than 10%, including 5 cases of 10%-15%, 8 cases of 15%-20%, and 1 case of 24%. All patients were treated by double EndoButton suture fixation Latarjet procedure. The operation time and complications were recorded. The shoulder function and pain were evaluated by the American Association for Shoulder and Elbow Surgery (ASES) score, Rowe score, Instability Severity Index Score (ISIS), and visual analogue scale (VAS) score before and after operation. The range of motion of the shoulder was recorded, including forward flexion, 0° external rotation, and abduction 90° external rotation. The position, healing, and resorption of the bone mass were evaluated by three-dimensional CT of shoulder joint after operation. All patients successfully completed the operation, and the operation time was 100-150 minutes, with an average of 119.7 minutes. There was no complications such as infection, vascular and nerve injury. All patients were followed up 12-20 months, with an average of 15.6 months. During the follow-up, 4 patients had bone mass separation, absorption, and recurrent anterior dislocation, and the shoulder joint fear test was positive. Imaging of the remaining patients showed that the bone mass healed well, no anterior dislocation recurrence occurred, and the healing time was 3-7 months (mean, 4.7 months). At last follow-up, the range of motion, ASES score, Rowe score, ISIS score, and VAS score of the patients significantly improved when compared with those before operation ( P<0.05). The effectiveness of double EndoButton suture fixation Latarjet procedure for the treatment of anterior shoulder dislocation with glenoid bone defect caused by military training injury is satisfactory.

A fading radius valley towards M dwarfs, a persistent density valley across stellar types

The radius valley separating super-Earths from mini-Neptunes is a fundamental benchmark for theories of planet formation and evolution. Observations show that the location of the radius valley decreases with decreasing stellar mass and with increasing orbital period. Here, we build on our previous pebble-based formation model. Combined with photoevaporation after disc dispersal, it has allowed us to unveil the radius valley as a separator between rocky and water-worlds. In this study, we expand our model for a range of stellar masses spanning from 0.1 to 1.5 M⊙. We find that the location of the radius valley is well described by a power-law in stellar mass as Rvalley = 1.8197 M⋆0.14(+0.02/−0.01), which is in excellent agreement with observations. We also find very good agreement with the dependence of the radius valley on orbital period, both for FGK and M dwarfs. Additionally, we note that the radius valley gets filled towards low stellar masses, particularly at 0.1–0.4 M⊙, yielding a rather flat slope in Rvalley − Porb. This is the result of orbital migration occurring at lower planet mass for less massive stars, which allows for low-mass water-worlds to reach the inner regions of the system, blurring the separation in mass (and size) between rocky and water worlds. Furthermore, we find that for planetary equilibrium temperatures above 400 K, the water in the volatile layer exists fully in the form of steam, puffing the planet radius up (as compared to the radii of condensed-water worlds). This produces an increase in planet radii of ∼30% at 1 M⊕ and of ∼15% at 5 M⊕ compared to condensed-water worlds. As with Sun-like stars, we find that pebble accretion leaves its imprint on the overall exoplanet population as a depletion of planets with intermediate compositions (i.e. water mass fractions of ∼0 − 20%), carving an planet-depleted diagonal band in the mass-radius (MR) diagrams. This band is better visualised when plotting the planet’s mean density in terms of an Earth-like composition. This change in coordinates causes the valley to emerge for all the stellar mass cases.

Insolvency (Bankruptcy) Procedure: Quo Vadis?

The paper examines the conceptual role of the insolvency (bankruptcy) procedure and the emerging trend towards the dominance of this legal mechanism over other (basic) legal categories. Three key categories are given as examples: the institute of non-interference in private affairs, which in the opposite case is transformed into intervention; the institute of limited liability of the founder (participant) and their legal entity, which presupposes a clear separation of the property masses of these subjects; and the institute of limitation period. It is proved that the bankruptcy procedure modifies the perception of the mentioned categories. Intervention becomes acceptable, which finds expression, for example, in the admissibility of challenging transactions and analyzing the debtor’s economic activities. The boundaries of the assets of a legal entity and an individual are blurred out in the context of the institution of subsidiary liability in bankruptcy. Only the statute of limitations, due to current court practice, is still subject to fewer changes, which are nevertheless present.The author concludes that it is unacceptable to consider the institution of bankruptcy as an instrument of unlimited suppression of other legal structures in favor of the interests of the creditor community. An attempt has been made to demonstrate that the legal essence of the institution of insolvency is much broader than is commonly believed. This, in turn, explains the inadmissibility and danger of perceiving bankruptcy proceedings as a kind of «sacred» legal phenomenon.