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The exploration of artificial metal-peptide assemblies (MPAs) is one of the most exciting fields because of their great potential for simulating the dynamics and functionality of natural proteins. However, unfavorable enthalpy changes make forming discrete complexes with large and adaptable cavities from flexible peptide ligands challenging. Here, we present a strategy integrating metal-cluster building blocks and peptides to create chiral metal-peptide assemblies and get a family of enantiopure [R-/S-Ni 3 L 2 ] n (n = 2, 3, 6) MPAs, including the R-/S-Ni 6 L 4 capsule, the S-Ni 9 L 6 trigonal prism, and the R-/S-Ni 18 L 12 octahedron cage. X-ray crystallography shows MPA formation reactions are highly solvent-condition-dependent, resulting in significant changes in ligand conformation and discrete cavity sizes. Moreover, we demonstrate that a structure transformation from Ni 18 L 12 to Ni 9 L 6 in the presence of benzopyrone molecules depends on the peptide conformational selection in crystallization. This work reveals that a metal-cluster building block approach enables facile bottom-up construction of artificial metal-peptide assemblies., (© 2024. The Author(s).)

In a molecule formed by two atoms, energy difference between bonding and antibonding orbitals depends on distance between the two atoms. However, exploring molecular orbitals of two natural atoms with tunable distance has remained an outstanding experimental challenge. Graphene quantum dots can be viewed as relativistic artificial atoms, thus offering a unique platform to study molecular physics. Here, through scanning tunneling microscope, we create and directly visualize the formation process of relativistic artificial molecules based on two coupled graphene quantum dots with tunable distance. Our study indicates that energy difference between the bonding and antibonding orbitals of the lowest quasibound state increases linearly with inverse distance between the two graphene quantum dots due to the relativistic nature of the artificial molecule. For quasibound states with higher orbital momenta, the coupling between these states leads to half-energy spacing of the confined states because the length of the molecular-like orbit is approximately twice that of the atomic-like orbit. Evolution from ring-like whispering-gallery modes in the artificial atoms to figure-eight orbitals in the artificial molecules is directly imaged. The ability to resolve the coupling and orbitals of the relativistic artificial molecule at the nanoscale level yields insights into the behavior of quantum-relativistic matter., (© 2024. The Author(s).)

In the last decade, chirality-induced spin selectivity (CISS) has undergone intensive study. However, there remain several critical issues, such as the microscopic mechanism of CISS, especially transverse CISS where electrons are injected perpendicular to the helix axis of chiral molecules, quantitative agreement between experiments and theory, and at which level the molecular handedness is key to the CISS. Here, we address these issues by performing a combined experimental and theoretical study on conducting polyaniline helical nanofibers which are synthesized in the absence of any chiral species. Large spin polarization is measured in both left- and right-handed nanofibers for electrons injected perpendicular to their helix axis, and it will be reversed by switching the nanofiber handedness. We first develop a theoretical model to study this transverse CISS and quantitatively explain the experiment. Our results reveal that our theory provides a unifying scheme to interpret a number of CISS experiments, quantitative agreement between experiments and numerical calculations can be achieved by weak spin-orbit coupling, and the supramolecular handedness is sufficient for spin selectivity without any chiral species.

Tropomyosin (TM) is the main allergen in shrimp ( Litopenaeus vannamei ). In this study, the effects of allergenicity and structure of TM by glycosylation (GOS-TM), phosphate treatment (SP-TM), and glycosylation combined with phosphate treatment (GOS-SP-TM) were investigated. Compared to GOS-TM and SP-TM, the IgG/IgE binding capacity of GOS-SP-TM was significantly decreased with 63.9 ± 2.0 and 49.7 ± 2.7%, respectively. Meanwhile, the α-helix content reduced, surface hydrophobicity increased, and 10 specific amino acids (K 30 , K 38 , S 39 , K 48 , K 66 , K 74 , K 128 , K 161 , S 210 , and K 251 ) were modified by glycosylation on six IgE linear epitopes of GOS-SP-TM. In the BALB/c mice allergy model, GOS-SP-TM could significantly reduce the levels of specific IgE, IgG1, and CD4 + IL-4 + , while the levels of IgG2a, CD4 + CD25 + Foxp3 + , and CD4 + IFN-γ + were increased, which equilibrated Th1 and Th2 cells, thus alleviating allergic symptoms. These results indicated that glycosylation combined with phosphate treatment can provide a new insight into developing hypoallergenic shrimp food.

To investigate the levels of 131I activity in thyroid of workers at the place of radioiodine therapy and their main influential factors in China, 341 workers at 38 hospitals performing radioiodine therapy procedure in five provinces were recruited to be measured in 2021. A hand-held gamma spectrometer with NaI(Tl) probe was plastered to the thyroids and thighs of the subjects during the measurement, and each measurement time was 120 s. The internal exposure dose was calculated, and the committed effective dose was estimated. In 86 (25.22%) of the 341 examined workers, 131I thyroid activity was above minimum detectable activity (MDA, 26.6 Bq). The maximum activity was 4.9 × 103 Bq. The detection results above MDA were at 22 (57.89%) different hospitals. The detectable rate for private hospitals (4.8%) was significantly lower than that for public hospitals (26.6%), P < 0.05. The detectable rate for hospitals in provincial capital cities (15.4%) was significantly lower than in nonprovincial capital cities (41.7%), P < 0.001. The detectable rate for hospitals engaged in 131I therapy for thyroid cancer (31.2%) was significantly higher than only for hyperthyroidism (10.3%), P < 0.001. A total of 32 subjects' committed effective dose might exceed 1 mSv. Results indicated the 131I activity in the thyroid of workers at the place of radioiodine varied considerably in China, and mainly related to ownership, location and therapy program of the hospitals., (© The Author(s) 2024. Published by Oxford University Press on behalf of The Japanese Radiation Research Society and Japanese Society for Radiation Oncology.)

Topological systems hosting gapless boundary states have attracted huge attention as promising components for next-generation information processing, attributed to their capacity for dissipationless electronics. Nevertheless, recent theoretical and experimental inquiries have revealed the emergence of energy dissipation in precisely quantized electrical transport. Here, we present a criterion for the realization of truly no-dissipation design, characterized as N in = N tunl + N bs , where N in , N tunl , and N bs represent the number of modes participating in injecting, tunneling, and backscattering processes, respectively. The key lies in matching the number of injecting, tunneling, and backscattering modes, ensuring the equilibrium among all engaged modes inside the device. Among all the topological materials, we advocate for the indispensability of Chern insulators exhibiting higher Chern numbers to achieve functional devices and uphold the no-dissipation rule simultaneously. Furthermore, we design the topological current divider and collector, evading dissipation upon fulfilling the established criterion. Our work paves the path for developing the prospective topotronics.

We propose a universal spin superconducting diode effect (SDE) induced by spin-orbit coupling (SOC) in systems with spin-triplet correlations, where the critical spin supercurrents in opposite directions are unequal. By analysis from both the Ginzburg-Landau theory and energy band analysis, we show that the spin-↑↑ and spin-↓↓ Cooper pairs possess opposite phase gradients and opposite momenta from the SOC, which leads to the spin SDE. Two superconductors with SOC, a p-wave superconductor as a toy model and a practical superconducting nanowire, are numerically studied and they both exhibit spin SDE. In addition, our theory also provides a unified picture for both spin and charge SDEs.

An efficient approach was developed for the synthesis of the well-known BlueCage by pre-bridging two 2,4,6-tris(4-pyridyl)-1,3,5-triazine (TPT) panels with one linker followed by cage formation in a much improved yield and shortened reaction time. Such a stepwise methodology was further applied to synthesize three new pyridinium organic cages, C2 , C3 , and C4 , where the low-symmetry cages C3 and C4 with angled panels demonstrated better recognition properties toward 1,1'-bi-2-naphthol (BINOL) than the high-symmetry analogue C2 featuring parallel platforms.

Energy dissipation is of fundamental interest and crucial importance in quantum systems. However, whether energy dissipation can emerge without backscattering inside topological systems remains a question. As a hallmark, we propose a microscopic picture that illustrates energy dissipation in the quantum Hall (QH) plateau regime of graphene. Despite the quantization of Hall, longitudinal, and two-probe resistances (dubbed as the quantum limit), we find that the energy dissipation emerges in the form of Joule heat. It is demonstrated that the non-equilibrium energy distribution of carriers plays much more essential roles than the resistance on energy dissipation. Eventually, we suggest probing the phenomenon by measuring local temperature increases in experiments and reconsidering the dissipation typically ignored in realistic topological circuits., (Copyright © 2023. Published by Elsevier B.V.)

Objective: Objective To analyze the relationship between the survival outcomes of pancreatic cancer patients with obstructive jaundice and various clinical and pathological factors. Methods: A case series study was conducted, where clinical data from pancreatic cancer patients with obstructive jaundice, who were admitted to the Cancer Hospital of Tianjin Medical University between March 2022 and May 2023, were retrospectively gathered. Factors potentially affecting patient prognosis were initially analyzed using univariate analysis, followed by multivariate analysis using the Cox regression model for selected factors. A P -value of less than 0.05 was deemed statistically significant. Results: The study included 104 patients, comprising 69 males and 35 females, with a median age of 62 years (ranging from 38 to 85 years). Of these, 76 patients (73.1%) were followed until death, with a median survival time of 8.9 (6.2,11.5) months. The number of deaths versus surviving cases at 6 and 12 months were 20/75 and 64/14, respectively, resulting in estimated survival rates of 79.6% and 22.8%. Univariate analysis identified factors such as weight loss, primary site, TNM stage, liver metastasis, number of organs with tumor, stage at which jaundice appeared, CA19-9 levels, albumin levels, and D-dimer levels as significant in influencing prognosis (all P <0.05). Multivariate analysis revealed TNM stage, number of organs with tumor, method of jaundice treatment, albumin levels, and D-dimer levels as independent prognostic factors (all P <0.05). Conclusion: In pancreatic cancer patients presenting with obstructive jaundice, close monitoring of weight loss, primary site, TNM stage, liver metastasis, number of organs with tumor, the timing of jaundice occurrence, method of jaundice treatment, CA19-9, albumin, and D-dimer levels is crucial, as these factors may significantly impact the patient's survival and prognosis.

Phase singularities are phase-indeterminate points where wave amplitudes are zero, which manifest as phase vertices or wavefront dislocations. In the realm of optical and electron beams, the phase singularity has been extensively explored, demonstrating a profound connection to orbital angular momentum. Direct local imaging of the impact of orbital angular momentum on phase singularities at the nanoscale, however, remains challenging. Here, we study the role of orbital angular momentum in phase singularities in graphene, particularly at the atomic level, through scanning tunneling microscopy and spectroscopy. Our experiments demonstrate that the scatterings between different orbital angular momentum states, which are induced by local rotational symmetry-breaking potentials, can generate additional phase singularities, and result in robust single-wavefront dislocations in real space. Our results pave the way for exploring the effects of orbital degree of freedom on quantum phases in quasiparticle interference processes., (© 2024. The Author(s).)

Background: Cushing disease (CD) is a rare clinical neuroendocrine disease. CD is characterized by abnormal hypercortisolism induced by a pituitary adenoma with the secretion of adrenocorticotropic hormone. Individuals with CD usually exhibit atrophy of gray matter volume. However, little is known about the alterations in topographical organization of individuals with CD. This study aimed to investigate the structural covariance networks of individuals with CD based on the gray matter volume using graph theory analysis., Methods: High-resolution T1-weighted images of 61 individuals with CD and 53 healthy controls were obtained. Gray matter volume was estimated and the structural covariance network was analyzed using graph theory. Network properties such as hubs of all participants were calculated based on degree centrality., Results: No significant differences were observed between individuals with CD and healthy controls in terms of age, gender, and education level. The small-world features were conserved in individuals with CD but were higher than those in healthy controls. The individuals with CD showed higher global efficiency and modularity, suggesting higher integration and segregation as compared to healthy controls. The hub nodes of the individuals with CD were Short insular gyri (G&#95;insular&#95;short&#95;L), Anterior part of the cingulate gyrus and sulcus (G&#95;and&#95;S&#95;cingul-Ant&#95;R), and Superior frontal gyrus (G&#95;front&#95;sup&#95;R)., Conclusions: Significant differences in the structural covariance network of patients with CD were found based on graph theory. These findings might help understanding the pathogenesis of individuals with CD and provide insight into the pathogenesis of this CD., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 Published by Elsevier Ltd.)

Spin-crossover (SCO) coordination cages are at the forefront of research for their potential in crafting next-generation molecular devices. However, due to the scarcity of SCO hosts and their own limited cavities, the interplay between the SCO host and the multiple guests binding has remained elusive. In this contribution, we present a family of pseudo-octahedral coordination cages (M 6 L 4 , M = Zn II , Co II , Fe II , and Ni II ) assembled from a tritopic tridentate ligand L with metal ions. The utilization of Fe II ion leads to the successful creation of the Fe 6 L 4 -type SCO cage. Host-guest studies of these M 6 L 4 cages reveal their capacity to encapsulate four adamantine-based guests. Notably, the spin transition temperature T 1/2 of Fe 6 L 4 is dependent on the multiple guests encapsulated. The inclusion of adamantine yields an unprecedented T 1/2 shift of 54 K, a record shift in guest-mediated SCO coordination cages to date. This drastic shift is ascribed to the synergistic effect of multiple guests coupled with their optimal fit within the host. Through a straightforward thermodynamic cycle, the binding affinities of the high-spin (HS) and low-spin (LS) states are separated from their apparent binding constant. This result indicates that the LS state has a stronger binding affinity for the multiple guests than the HS state. Exploring the SCO thermodynamics of host-guest complexes allows us to examine the optimal fit of multiple guests to the host cavity. This study reveals that the T 1/2 of the SCO host can be manipulated by the encapsulation of multiple guests, and the SCO cage is an ideal candidate for determining the multiple guest fit.

Controlled self-assembly of predetermined multi-nuclear lanthanide organic polyhedra (LOPs) still presents a challenge, primarily due to the unpredictable coordination numbers and labile coordination geometries of lanthanide ions. In this study, through introducing triazole-based chelates to increase the chelating angle of C 2 -symmetric linear ligands and stabilize the coordination geometry of Eu(III) centers, M 4 L 6 -type (M = Eu III , L = ligand) tetrahedra were efficiently synthesized, especially a biphenyl-bridged ligand which is well known to form M 2 L 3 -type helicates. A series of LOPs were formed and characterized by high-resolution electrospray ionization time-of-flight mass spectroscopy (ESI-TOF-MS) and X-ray crystallography. Moreover, the europium complexes exhibit bright emission (luminescence quantum yield up to 42.4%) and circularly polarized luminescence properties (| g lum | up to 4.5 × 10 -2 ). This study provides a feasible strategy for constructing multi-nuclear luminescent LOPs towards potential applications.

Objective: To report the results of a dose survey conducted across 31 provinces in mainland China from 2017 to 2018 and to analyse the dose level to determine the national diagnostic reference levels (DRLs) for paediatric CT procedures., Methods: At least ten patients for each age group (0- < 1, 1- < 5, 5- < 10, 10- < 15 years) and each procedure (head, chest and abdomen) for each CT scanner were selected from four to eight hospitals in each province. The dose information (CTDI vol and DLP) was collected from the HIS or RIS-PACS systems. The median values in each CT scanner were considered the representative dose values for the paediatric patients in CT scanning. The national DRLs were estimated based on the 75th percentile distribution of the median values., Results: A total of 24,395 patients and 319 CT scanners were investigated across 262 hospitals. For paediatric CT scanning in 4 different age groups, the median (P 50 ) and the 75th percentile (P 75 ) of CTDI vol and DLP for each scanning procedure were calculated and reported. National DRLs were then proposed for each procedure and age group., Conclusion: The dose level of CT scanning for children in mainland China was reported for the first time. The DRLs for paediatric CT in the present study are similar to those in some Asian countries but higher than those in European countries., Clinical Relevance Statement: The paediatric CT is an extensively used tool in diagnosing paediatric disease; however, children are more sensitive to radiation. Establishing the diagnostic reference level of paediatric CT examination is necessary to reduce the dose of CT in children and promote the optimisation of medical exposure., Key Points: • The DRLs for 3 paediatric CT procedures (head, chest and abdomen) and 4 age groups (0- < 1, 1- < 5, 5- < 10, 10- < 15 years) were proposed in mainland China first time. • The examination parameter and dose for children need to be further optimised in China, especially to lower the tube voltage in paediatric CT., (© 2023. The Author(s), under exclusive licence to European Society of Radiology.)

Objective: To analyze the differences between trans-radial access (TRA) and trans-femoral access (TFA) in hepatic arterial perfusion chemotherapy (HAIC) in terms of patient experience, postoperative complications, and patient preferences; explore whether TRA in HAIC is associated with better patient experience and compliance; and determine whether it is safer than TFA. Methods: The study was a retrospective cohort study of patients with advanced hepatocellular carcinoma and liver metastases from colorectal cancer treated with HAIC. We enrolled a total of 91 patients with advanced liver malignancies treated with HAIC from November 2022 to May 2023 in the Department of Interventional Therapy and Hepatobiliary Medicine at Tianjin Medical University Cancer Hospital. The patients were divided into three groups: group TRA ( n =20, receiving TRA HAIC only), group TFA ( n =33, receiving TFA HAIC only), and crossover group [ n =19, receiving TFA HAIC (Cross-TFA group) first, followed by TRA HAIC (Cross-TRA group)]. Meanwhile, to facilitate the expression of partial results, all patients receiving TRA HAIC were defined as the TRA-HAIC group ( n =39, TRA+Cross-TRA group), and all patients receiving TFA HAIC were defined as the TFA-HAIC group ( n =52, TFA+Cross-TFA group). The primary research index was the Quality of Life (QOL) visualization scale score. The secondary research index included approach-related and catheter-related adverse events, duration of surgery, and mean length of patient stay. We used various statistical methods such as Mann-Whitney U test, t -test, Chi-square test, Fisher's exact test, univariate logistic regression analysis, and multi-factor analysis. Results: TRA patients had significantly lower QOL scores than TFA patients (all P <0.001). The QOL scores of the Cross-TRA group were significantly lower than those of the Cross-TFA group (pain at the puncture site Z =-3.24, P =0.001, others P <0.001). The QOL scores of the Cross-TRA group were compared with those of the TRA group, which showed that the scores of the Cross-TRA group in overall discomfort ( Z =-3.07, P =0.002), postoperative toilet difficulty ( Z =-2.12, P =0.034), and walking difficulty ( Z =-2.58, P =0.010) were significantly lower than those of the TRA group. Satisfaction scores were significantly higher in the Cross-TRA group than in the Cross-TFA group ( Z =-3.78, P <0.001), and patients were more likely to receive TRA HAIC as the next procedure ( χ 2 =30.42, P <0.001). In terms of mean length of stay, patients receiving TRA HAIC had a significantly lower mean length of stay than those receiving TFA HAIC (50.1±3.2 h vs. 58.4±6.4 h, t =7.98, P <0.001). The incidence of radial artery occlusion (RAO) as an approach-related adverse event was 15.4% (6/39) in the TRA-HAIC group, which was significantly higher than that in the TFA-HAIC group (15.4% vs. 0, χ 2 =8.56, P =0.005). Notably, multifactorial analysis of RAO-related factors showed that intraoperative enoxaparin use and patency of radial artery flow during pressure were significantly associated with a reduced risk of postoperative RAO ( P =0.037 for enoxaparin use and P =0.049 for pressure). Conclusions: With respect to procedure approach, TRA was significantly better than TFA in terms of patient satisfaction and mean length of stay. Through further process optimization and prevention of adverse reactions, the incidence of adverse reactions can be maintained at a relatively low level, so that patients can benefit from TRA in future operations in terms of cost-effectiveness and medical efficiency.

Accurate navigation and targeting are critical for neurological interventions including biopsy and deep brain stimulation. Real-time image guidance further improves surgical planning and MRI is ideally suited for both pre- and intra-operative imaging. However, balancing spatial and temporal resolution is a major challenge for real-time interventional MRI (i-MRI). Here, we proposed a deep unrolled neural network, dubbed as LSFP-Net, for real-time i-MRI reconstruction. By integrating LSFP-Net and a custom-designed, MR-compatible interventional device into a 3 T MRI scanner, a real-time MRI-guided brain intervention system is proposed. The performance of the system was evaluated using phantom and cadaver studies. 2D/3D real-time i-MRI was achieved with temporal resolutions of 80/732.8 ms, latencies of 0.4/3.66 s including data communication, processing and reconstruction time, and in-plane spatial resolution of 1 × 1 mm 2 . The results demonstrated that the proposed method enables real-time monitoring of the remote-controlled brain intervention, and showed the potential to be readily integrated into diagnostic scanners for image-guided neurosurgery., (© 2023. The Author(s).)

Public exposure to radon has attracted increasing public concern. The newly issued "Standards for indoor air quality (GB/T 18883-2022)" has revised the radiological parameters of radon. This study analyzed and discussed the relevant technical contents about the derivation of radon limit, including the distribution level for indoor radon, exposure pathway, health effects, and the process for establishing the standard limits. Specific implementation and evaluation suggestions are also proposed.

Upconversion (UC) is a fascinating anti-Stokes-like optical process with promising applications in diverse fields. However, known UC mechanisms are mainly based on direct energy transfer between metal ions, which constrains the designability and tunability of the structures and properties. Here, we synthesize two types of Ln 8 L 12 -type (Ln for lanthanide ion; L for organic ligand L 1 or L 2 R/S ) lanthanide-organic complexes with assembly induced excited-multimer states. The Yb 8 (L 2 R/S ) 12 assembly exhibits upconverted multimer green fluorescence under 980 nm excitation through a cooperative sensitization process. Furthermore, upconverted red emission from Eu 3+ on the heterometallic (Yb/Eu) 8 L 12 assemblies is also realized via excited-multimer mediated energy relay. Our findings demonstrate a new strategy for designing UC materials, which is crucial for exploiting photofunctions of multicomponent lanthanide-organic complexes.

Developing efficient adsorbents to capture radioactive iodine produced from nuclear wastes is highly desired. Here we report the facial synthesis of a hexacationic imidazolium organic cage and its iodine adsorption properties. Crucial role of counteranions has been disclosed for iodine capture with this cage, where distinct iodine capture behaviors were observed when different counteranions were used. Mechanistic investigations, especially with the X-ray crystallographic analysis of the iodine-loaded sample, allowed the direct visualization of the iodine binding modes at the molecular level. A network of multiple non-covalent interactions including hydrogen bonds, halogen bonds, anion···π interactions, electrostatic interaction between polyiodides and the hexacationic skeleton of the cage are found responsible for the observed high iodine capture performance. Our results may provide an alternative strategy to design efficient iodine adsorbents., (© 2023. Springer Nature Limited.)

Quantum spin Hall effect is characterized by topologically protected helical edge states. Here we study the thermal dissipation of helical edge states by considering two types of dissipation sources. The results show that the helical edge states are dissipationless for normal dissipation sources with or without Rashba spin-orbit coupling in the system, but they are dissipative for spin dissipation sources. Further studies on the energy distribution show that electrons with spin-up and spin-down are both in their own equilibrium without dissipation sources. Spin dissipation sources can couple the two subsystems together to induce voltage drop and non-equilibrium distribution, leading to thermal dissipation, while normal dissipation sources cannot. With the increase of thermal dissipation, the subsystems of electrons with spin-up and spin-down evolve from non-equilibrium finally to mutual equilibrium. In addition, the effects of disorder on thermal dissipation are also discussed. Our work provides clues to reduce thermal dissipation in the quantum spin Hall systems., (© 2023 IOP Publishing Ltd.)

Charge plays a crucial role in the function of molecular and supramolecular systems, but coordination hosts capable of orthogonal charge regulation remain elusive so far. In this study, we report the condition-dependent self-assembly of charge-reversible lanthanide-organic tetra-capped octahedral cages, i.e., [Ln 6 (H 3 L ) 4 ] 6+ and [Ln 6 L 4 ] 6- , from a series of lanthanide ions (Ln 3+ ; Ln = Lu, Yb, Eu) and a tritopic tetradentate acylhydrazone ligand (H 6 L ) featuring multiple deprotonation states and propeller conformations. While direct self-assembly under basic conditions produced a mixture of various Δ x Λ 6- x -[Ln 6 L 4 ] 6- ( x = 0-6) stereoisomers, racemic Δ 6 - and Λ 6 -[Ln 6 L 4 ] 6- could be exclusively obtained from the first self-assembly of Δ 6 - and Λ 6 -[Ln 6 (H 3 L ) 4 ] 6+ under neutral conditions followed by post-assembly deprotonation. Rich isomerism on the tetra-capped octahedral cages arising from the coupling between the metal-centered Δ/Λ chirality and the ligand conformations has been discussed based on X-ray single-crystal structures of the C 3 -symmetric Δ 3 Λ 3 -Ln 6 L 4 and T -symmetric Δ 6 /Λ 6 -Ln 6 L 4 complexes. Host-guest studies confirmed that positively charged rac -Δ 6 /Λ 6 -[Ln 6 (H 3 L ) 4 ] 6+ could bind anionic sulfonates, and negatively charged rac -Δ 6 /Λ 6 -[Ln 6 L 4 ] 6- exhibited strong encapsulation ability toward ammonium guests, where acid/base-triggered guest uptake/release could be realized taking advantage of the charge reversibility of the cage. Moreover, photophysical studies revealed visible-light-sensitized and guest-encapsulation-enhanced NIR emissions on the rac -Δ 6 /Λ 6 -Yb 6 L 4 cage. This work not only enriches the library of functional lanthanide-organic cages but also provides a promising candidate with charge reversibility for the development of smart supramolecular materials.

Recent experiments have revealed multiple borophene phases of distinct lattice structures, suggesting that the unit cells of ν 1/6 and ν 1/5 boron sheets, namely α and β chains, serve as building blocks to assemble into novel borophene phases. Motivated by these experiments, we present a theoretical study of electron transport along two-terminal quasiperiodic borophene nanoribbons (BNRs), with the arrangement of the α and β chains following the generalized Fibonacci sequence. Our results indicate that the energy spectrum of these quasiperiodic BNRs is multifractal and characterized by numerous transmission peaks. In contrast to the Fibonacci model that all the electronic states should be critical, both delocalized and critical states appear in the quasiperiodic BNRs, where the averaged resistance saturates at the inverse of one conductance quantum for the delocalized states in the large length limit and contrarily exhibits a power-law dependence on the nanoribbon length for the critical states. Besides, the self-similarity is observed from the transmission spectrum, where the conductance curves overlap at different energy regions of two quasiperiodic BNRs of different Fibonacci indices and the resistance curves are analogous to each other at different energy scales of a single quasiperiodic BNR. These results complement previous studies on quasiperiodic systems where the multifractal energy spectrum and the self-similarity are observed by generating quasiperiodic potential energies, suggesting that borophene may provide an intriguing platform for understanding the structure-property relationships and exploring the physical properties of quasiperiodic systems.

Ln 2 L 3 -type supramolecular architectures have received significant attention recently due to their unique magnetism and optical properties. Herein, we report the triple-stranded Ln 2 L 3 -type lanthanide molecular quasi-lanterns, which are fabricated by the deprotonation self-assembly of a linear ligand featuring a β-diketone chelating claw and 2,2'-bipyridine (bpy) moiety with lanthanide ions (Ln = Eu 3+ and Dy 3+ ). The crystal structure analysis indicates that Eu 3+ and Dy 3+ ions are all coordinated by eight oxygen donors but in different coordination geometries. The eight oxygen donors in Eu 2 L 3 and Dy 2 L 3 are arranged in a square antiprism and triangular dodecahedron geometry, respectively. Taking into account the fact that the bpy moiety has a strong coordination affinity for transition metal ions, luminescence sensing toward Cu 2+ ions has been demonstrated with Eu 2 L 3 , bearing a detection of limit as low as 2.84 ppb. The luminescence sensing behavior of Eu 2 L 3 is ascribed to the formation host-guest complex between Eu 2 L 3 and Cu 2+ ions with a 1:2 binding ratio. Dynamic AC susceptibility measurements for Dy 2 L 3 reveal the relaxation of magnetization in it. This work provides a potential way for design and fabrication of lanthanide-based molecular materials with functions endowed by the ligands., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Well-defined 3d-4f heterometallic supramolecular architectures have attracted attention because of their applications in the field of luminescence and magnetism. However, covalent metallo-supramolecular discrete complexes, decorated with hetero-metallic vertices, have never been reported because of the difficulties in design and control. Herein, we report a series of covalent metallo-supramolecular discrete complexes with 3d-4f vertices synthesized by hierarchical subcomponent self-assembly of tris(2-aminoethyl)amine, 2,6-diformyl- p -cresol, and lanthanide ions (Ln) with different amines and transition metal ions. The programmable self-assembly process results in the formation of triple-stranded hetero-metallic covalent organic discrete complexes, namely 3a-3c-(Ln, Zn) (Ln = Sm III , Eu III , Dy III , Yb III and Lu III ) and 3a'-(Dy, Co), which are characterized by nuclear magnetic resonance (NMR) analysis, electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS), and single-crystal X-ray analysis. Photophysical investigations disclose that the organic skeleton of 3a-(Ln, Zn) exhibits an excellent sensitizing ability toward Sm III , Eu III , and Yb III ions, displaying characteristic luminescence emission in both the visible and near-infrared (NIR) regions. AC susceptibility measurements of 3a'-(Dy, Co) reveal the frequency-independent performance under zero dc field, suggesting the absence of slow relaxation of magnetization. This work offers a new approach for the fabrication of discrete metallic covalent architectures with 3d-4f vertices.

Brønsted-base active sites on a Pd 4 L 2 cage facilitates enhanced catalytic efficiency, wide substrate scope and high turnover number (TON) for the one-pot photooxidation/Knoevenagel condensation reaction under mild conditions.

The radioactive safety of drinking water has attracted increasing public concern. The newly issued Standards for Drinking Water Quality (GB5749-2022) in China has revised the radiological parameters. This article provides an overview of the main sources, levels of radionuclides in drinking water, and summarized the individual doses criterion and adverse health effects associated with exposure of the public to radionuclides from drinking-water. It analyzes and discusses the relevant revision content of radiological parameters, including the guidance values for screening gross α and gross β, subtracting the contribution of potassium-40 from gross β activity when the gross β activity concentration exceeds the screening level, and the basis for establishing the limit values of reference indices uranium and radium-226. Specific implementation and evaluation suggestions are also proposed.

We report the syntheses and host-guest chemistry of two interconvertible coordination cages, Pd 2 L 2 and Pd 1 L 1 , from a dynamic macrocycle ligand (L) and a cis-blocking (tmen)Pd(NO 3 ) 2 (tmen = tetramethylethylenediamine) unit (Pd). The water-soluble macrocyclic L, which can bind various polycyclic aromatic hydrocarbon (PAH) guests in its cis-conformation, was constructed via four pyridinium bonds between two 2,4,6-tri(4-pyridyl)-1,3,5-triazine [TPT] panels and two p -xylene bridges. We selectively formed each cage either by changing the reaction concentration/solvent/temperature or through induced-fit guest encapsulation, while direct assembly of L and Pd resulted in a mixture of Pd 2 L 2 and Pd 1 L 1 in equilibrium. X-ray structures of the free ligand and the host-guest complexes confirmed the induce-fit adaptive changes in the ligand's conformation and the cage's cavity. This work demonstrates a useful strategy for designing multistimuli-responsive supramolecular hosts by coordination self-assembly with macrocyclic ligands featuring rich conformational freedom.

Discrete organopalladium coordination cages have shown great potential in applications ranging from molecular recognition and sensing, drug delivery to enzymatic catalysis. While many of the known organopalladium cages are homoleptic structures with regular polyhedral shapes and symmetric inner cavities, heteroleptic cages with complex architectures and new functions coming from their anisotropic cavities have received an increasing attention recently. In this concept article, we discuss a powerful combinatorial coordination self-assembly strategy toward the construction of a family of organopalladium cages, including both homoleptic and heteroleptic ones, from a given library of ligands. Within such a cage family, the heteroleptic cages often feature systematically fine-tuned structures and emergent properties, distinct from their parent homoleptic counterparts. We hope the concepts and examples provided in this article can offer some rational guidance for the design of new coordination cages toward advanced functions., (© 2023 Wiley-VCH GmbH.)

Organic pollutants cause severe environmental problems because of their damage to human health and ecological systems. Photocatalytic degradation of persistent organic pollutants is of great importance to address these hazards. Herein, we report a lanthanide organic polyhedra-based hybrid material Gd 8 L 12 ⊂MSN with the capability of photocatalytic dye degradation. Gd 8 L 12 ⊂MSN was prepared by embedding the Gd 8 L 12 complex into mesoporous silica nanoparticles (MSNs) using a "ship-in-a-bottle" strategy. Photocurrent response tests revealed that this hybrid material is a potential semiconductor and could generate a rapid and steady photocurrent upon irradiation. Further dye degradation experiments indicated that it could photocatalyze the degradation of familiar organic dyes. Thereinto, compared with the critical Gd 8 L 12 complex, the hybrid material exhibited an acceleration of 2.4 times and realized reusability. This not only offers a potential advanced photocatalyst for degrading persistent organic pollutants, but also provides a strategy for the application of supramolecular materials in environmental science., (© 2023 Wiley-VCH GmbH.)

With the rapid development of nuclear medicine, the number of nuclear medical staff has increased a lot in the past few years in China. Close-range operations, such as preparation and injections of radiopharmaceuticals, are usually carried out in nuclear medicine department. And the use of unsealed radionuclides may also create internal exposure risk. So, occupational exposure of nuclear medical staff is a main issue of occupational health management in China. In this paper, the occupational exposure level and requirements for radiation protection of nuclear medical staff are introduced to provide references for the related work that radiological health technical institutions carry out.

In relativistic physics, both atomic collapse in a heavy nucleus and Hawking radiation in a black hole are predicted to occur through the Klein tunneling process that couples particles and antiparticles. Recently, atomic collapse states (ACSs) were explicitly realized in graphene because of its relativistic Dirac excitation with a large "fine structure constant." However, the essential role of the Klein tunneling in the ACSs remains elusive in experiment. Here we systematically study the quasibound states in elliptical graphene quantum dots (GQDs) and two coupled circular GQDs. Bonding and antibonding molecular collapse states formed by two coupled ACSs are observed in both systems. Our experiments supported by theoretical calculations indicate that the antibonding state of the ACSs will change into a Klein-tunneling-induced quasibound state revealing deep connection between the ACSs and the Klein tunneling.

Objectives: To establish a system for simultaneous detection of miR-888 and miR-891a by droplet digital PCR (ddPCR), and to evaluate its application value in semen identification., Methods: The hydrolysis probes with different fluorescence modified reporter groups were designed to realize the detection of miR-888 and miR-891a by duplex ddPCR. A total of 75 samples of 5 body fluids (including peripheral blood, menstrual blood, semen, saliva and vaginal secretion) were detected. The difference analysis was conducted by Mann-Whitney U test. The semen differentiation ability of miR-888 and miR-891a was evaluated by ROC curve analysis and the optimal cut-off value was obtained., Results: There was no significant difference between the dual-plex assay and the single assay in this system. The detection sensitivity was up to 0.1 ng total RNA, and the intra- and inter-batch coefficients of variation were less than 15%. The expression levels of miR-888 and miR-891a detected by duplex ddPCR in semen were both higher than those in other body fluids. ROC curve analysis showed that the AUC of miR-888 was 0.976, the optimal cut-off value was 2.250 copies/μL, and the discrimination accuracy was 97.33%; the AUC of miR-891a was 1.000, the optimal cut-off value was 1.100 copies/μL, and the discrimination accuracy was 100%., Conclusions: In this study, a method for detection of miR-888 and miR-891a by duplex ddPCR was successfully established. The system has good stability and repeatability and can be used for semen identification. Both miR-888 and miR-891a have high ability to identify semen, and the discrimination accuracy of miR-891a is higher.

We designed and synthesized a semi-rigid bis-tridentate ligand L which could undergo a trans -to- cis conformational transition when coordinated onto lanthanum ions through the rotation of the single bond on the central terphenyl bridge. By adjusting the metal/ligand ratio, a single-ligand bridged dinuclear complex La 2 L 3 and an infinitely extending two-dimensional layered metal organic polymer (La 2 L 2 ) n can be obtained. Through the induction of the chiral auxiliary ligand G R / S , these two achiral assemblies could both be transformed into the chiral mononuclear three-component complex La LG R / S . In addition, we also realized a linear ee sensing for the auxiliary ligand by induced circular dichroism.

Structurally well-defined discrete d/f heterometallic complexes show diverse application potential in electrooptic and magnetic materials. However, precise control of the component and topology of such heterometallic compounds with fine-tuned photophysical properties is still challenging. Herein, we report the stereocontrolled syntheses of a series of Ln III -Pt II heterometallic cages through coordination-driven self-assembly of enantiopure alkynylplatinum-based metalloligands (L 1 R / S , L 2 R / S ) with lanthanide ions (Ln = Eu III , Yb III , Nd III , Lu III ). Taking advantage of the metal-to-ligand charge transfer (MLCT) excited state on the designed alkynylplatinum ligands, the excitation window for the sensitized near-infrared (NIR) luminescence on the Yb III - and Nd III -containing cages can be extended to the visible region (up to 500 nm). Linear temperature-dependent red and NIR emissions observed on the Ln 4 (L 2 R / S ) 6 (Ln III = Eu III and Yb III , respectively) complexes suggest their potential applications as luminescent temperature sensors, with sensitivities of -0.54% (Ln III = Eu III , 77-250 K) and -0.17% (Ln III = Yb III , 77-300 K) per K achieved. This work not only offers a good strategy to prepare new d/f heterometallic supramolecular cages but also paves the way for the design of stimuli-responsive luminescent materials.

Artificial hosts with rich conformational dynamics are attractive to supramolecular chemists due to their adaptive guest-binding properties and enzyme-like catalytic functions. We report here the adaptive self-assembly and host-guest catalysis of a new water-soluble organo-palladium host (Pd 2 L 2 ) built from a pyridinium-bonded macrocyclic ligand (L) and cis-blocked palladium corners (Pd). While the direct self-assembly of L with Pd gives rise to a dynamic mixture of products, both neutral polyaromatic hydrocarbons and an anionic polyoxometalate cluster (W 10 O 32 4- ) can template the dominant formation of the Pd 2 L 2 host. Guest-adaptive conformational changes and induced-fit cavity deformation of the Pd 2 L 2 host have been clearly observed in the crystal structures. Moreover, the installation of the electron-rich W 10 O 32 4- cluster within the cationic redox-active host (W 10 O 32 ⊂Pd 2 L 2 ) facilitates the efficient and selective C-H photooxidation of toluene derivatives to aldehyde products under mild conditions, thus representing an ideal platform for green supramolecular catalysis., (© 2022 Wiley-VCH GmbH.)

Recently, a half-quantized Hall conductance (HQHC) plateau was experimentally observed in a semimagnetic topological insulator heterostructure. However, the heterostructure was metallic with a nonzero longitudinal conductance, which contradicts the common belief that quantized Hall conductance is usually observed in insulators. In this work, we systematically study the surface transport of a semimagnetic topological insulator with both gapped and gapless Dirac surfaces in the presence of dephasing process. In particular, we reveal that the HQHC is directly related to the half-quantized chiral current along the edge of a strongly dephasing metal. The Hall conductance keeps a half-quantized value for large dephasing strengths, while the longitudinal conductance varies with Fermi energies and dephasing strengths. Furthermore, we evaluate both the conductance and resistance as a function of the temperature, which is consistent with the experimental results. Our results not only provide the microscopic transport mechanism of the HQHC, but also are instructive for the probe of the HQHC in future experiments.

Controllable arrangement of different ligands in a single assembly will not only bring increased complexity but also offers a new route to fine-tune the function of the designed architecture. We report here a combinatorial self-assembly with enPd(NO 3 ) 2 and three different ligands (L 1-3 ), which gave rise to a family of six palladium-organic cages (C1-6) with systematically varied shapes and cavities, including three new heteroleptic (Pd 5 L 1 2 L 2 , Pd 5 L 1 2 L 3 , Pd 4 L 2 L 3 ), one new homoleptic (Pd 4 L 3 2 ) cages, and two known homoleptic (Pd 6 L 1 4 , Pd 4 L 2 2 ) cages. Emergent functions due to the fusion of two half cavities on the heteroleptic cages from their parent homoleptic cages have been observed: the heteroleptic cages can form ternary complexes by co-encapsulation of both aromatic and aliphatic guests, while their homoleptic counterparts can only form binary complexes. Such a forced co-encapsulation effect endows the heteroleptic cages with enhanced catalytic power for the Knoevenagel condensation., (© 2022 Wiley-VCH GmbH.)

Introducing quantum confinement has uncovered a rich set of interesting quantum phenomena and allows one to directly probe the physics of confined (quasi-)particles. In most experiments, however, an electrostatic potential is the only available method to generate quantum dots in a continuous system to confine (quasi-)particles. Here we demonstrate experimentally that inhomogeneous pseudomagnetic fields in strained graphene can introduce exotic quantum confinement of massless Dirac fermions. The pseudomagnetic fields have opposite directions in the two distinct valleys of graphene. By adding and tuning real magnetic fields, the total effective magnetic fields in the two valleys are imbalanced. By that we realized valley-contrasting spatial confinement, which lifts the valley degeneracy and results in field-tunable valley-polarized confined states in graphene. Our results provide a new avenue to manipulate the valley degree of freedom.

Coordination hosts based on flexible ligands have received increasing attention due to their inherent adaptive cavities that often show induced-fit guest binding and catalysis like enzymes. Herein, we report the controlled self-assembly of a series of homo/heterometallic coordination hosts (Me 4 enPd) 2 n (ML) n [ n = 2/3; M = Zn(ii)/Co(ii)/Ni(ii)/Cu(ii)/Pd(ii)/Ag(i); Me 4 en: N , N , N ', N '-tetramethylethylenediamine] with different shapes (tube/cage) from a flexible tetraazacyclododecane-based pyridinyl ligand (L) and cis -blocking Me 4 enPd(ii) units. While the Ag(i)-metalated ligand (AgL) gave rise to the formation of a (Me 4 enPd) 4 (ML) 2 -type cage, all other M(ii) ions led to isostructural (Me 4 enPd) 6 (ML) 3 -type tubular complexes. Structural transformations between cages and tubes could be realized through transmetalation of the ligand. The buffering effect on the ML panels endows the coordination tubes with remarkable acid-base resistance, which makes the (Me 4 enPd) 6 (ZnL) 3 host an effective catalyst for the CO 2 to CO 3 2- conversion. Control experiments suggested that the integration of multiple active Zn(ii) sites on the tubular host and the perfect geometry match between CO 3 2- and the cavity synergistically promoted such a conversion. Our results provide an important strategy for the design of adaptive coordination hosts to achieve efficient carbon fixation., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

We present here the coordination self-assembly of a new heteroleptic (bpyPd) 4 L 1 L 2 2 coordination complex ( 1 ) from one novel pyridinium-functionalized bis-2,4,6-tris(pyridin-3-yl)-1,3,5-triazine (bis-3-TPT, L 1 ) macrocyclic ligand, two separate 3-TPT ( L 2 ) ligands, and four cis -blocking bpyPd(NO 3 ) 2 (bpy = 2,2'-bipyridine). While homoleptic self-assemblies with either L 1 or L 2 gave dynamic mixtures of products, a single thermodynamic heteroleptic complex was obtained driven by the shape complementarity of building blocks. Moreover, the redox-active nature of the heteroleptic assembly facilitates the highly efficient catalytic aerobic photo-oxidation of aromatic secondary alcohols under mild conditions.

The Berry phase plays an important role in determining many physical properties of quantum systems. However, tuning the energy spectrum of a quantum system via Berry phase is comparatively rare because the Berry phase is usually a fixed constant. Here, we report the realization of an unusual valley-polarized energy spectra via continuously tunable Berry phases in Bernal-stacked bilayer graphene quantum dots. In our experiment, the Berry phase of electron orbital states is continuously tuned from about π to 2π by perpendicular magnetic fields. When the Berry phase equals π or 2π, the electron states in the two inequivalent valleys are energetically degenerate. By altering the Berry phase to noninteger multiples of π, large and continuously tunable valley-polarized energy spectra are realized. Our result reveals the Berry phase's essential role in valleytronics and the observed valley splitting, on the order of 10 meV at a magnetic field of 1 T, is about 100 times larger than Zeeman splitting for spin, shedding light on graphene-based valleytronics.

A series of lanthanide-organic pincer hosts were synthesized, which showed allosteric-controlled metal ion binding selectivities due to the lanthanide-induced subtle changes of the central vacant binding site.

Background and Objective: This pilot study aimed to identify potential blood DNA methylation (BDM) biomarker genes for the diagnosis of liver fibrosis in non-alcoholic fatty liver disease (NAFLD)., Methods: We included a total of 16 NAFLD patients with significant (SLF, liver fibrosis stage ≥ 2) and 16 patients with non-significant liver fibrosis (NSLF, fibrosis stages 0-1). The association between BDM and liver fibrosis was analyzed. Genes were selected based on a stepwise-filtering with CpG islands containing significant differentially methylated probes., Results: The two groups of patients were distinguishable through both t-distributed stochastic neighbor embedding (t-SNE) analysis and unsupervised hierarchical clustering analysis based on their BDM status. BDM levels were significantly higher in the NSLF group than in the SLF group. The methylation levels in the island and shelf regions were also significantly higher in the NSLF group, as well as the methylation levels in the first exon, 3'-untranslated region, body, ExonBnd, non-intergenic region, transcription start site (TSS)1500, and TSS200 regions (all p < 0.05). BDM status was associated with greater histological liver fibrosis, but not with age, sex, or other histological features of NAFLD ( p < 0.05). The methylation levels of the hypomethylated CpG island region of CISTR , IFT140 , and RGS14 genes were increased in the NSLF group compared to the SLF group (all p < 0.05)., Conclusion: BDM may stratify NAFLD patients with significant and non-significant liver fibrosis. The CISTR , IFT140 , and RGS14 genes are potential novel candidate BDM biomarkers for liver fibrosis and these pilot data suggest further work on BDM biomarkers is warranted., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Sun, Tang, Wang, Zhu, Li, Ma, Huang, Hong, Li, Byrne, Targher, Liu, Lu, Ding and Zheng.)

The relativistic massless charge carriers with a Fermi velocity of about c/300 in graphene enable us to realize two distinct types of resonances (here, c is the speed of light in vacuum). One is the electron whispering-gallery mode in graphene quantum dots arising from the Klein tunneling of the massless Dirac fermions. The other is the atomic collapse state, which has never been observed in experiment with real atoms due to the difficulty of producing heavy nuclei with charge Z > 170; however, they can be realized near a Coulomb impurity in graphene with a charge Z ≥ 1 because of the "small" velocity of the Dirac excitations. Here we demonstrate that both the electron whispering-gallery modes and atomic collapse states coexist in graphene/WSe 2 heterostructure quantum dots due to the Coulomb-like potential near their edges. By applying a perpendicular magnetic field, we explore the evolution from the atomic collapse states to unusual Landau levels in the collapse regime., (© 2022. The Author(s).)