[Influence of paraspinal muscle degeneration and postoperative Roussouly classification restoration on mechanical complications in female patients with degenerative scoliosis after surgery].

Objective: To investigate the impact of lumbar paraspinal muscle degeneration and postoperative failure to restore ideal Roussouly classification on the occurrence of mechanical complications (MC) following long-segment spinal correction surgery in female patients with degenerative scoliosis (DS). Methods: The clinical data of 72 female DS patients who underwent long-segment spinal correction surgery in Gulou Hospital from June 2017 to November 2021 were retrospectively analyzed. According to whether restoring the ideal Roussouly classification after surgery, the patients were divided into R group(recovery group) (n=51) and N group(non-recovery group) (n=21). According to whether mechanical complications occurred after operation within two years, the patients were divided into MC (mechanical complications)group (n=24) and NMC(non-mechanical complications) group (n=48). The RM group (n=14) experienced mechanical complications in the R group, while the RN group (n=37) did not. The NM group (n=10) experienced mechanical complications in the N group, while the NN group (n=11) did not.Radiographic assessment included Sagittal parameters of spine and pelvis, standardized cross-sectional area (SCSA) and fat infiltration rate (FI%) of paraspinal muscle at each lumbar disc level. Results: The age of DS patients in this study was (61.4±6.2) years.The incidence of MC was 33.33%(n=24)in all patients. The incidence of MC was 27.45%(n=14)in group R and 47.62%(n=10) in group N. The correction amount of pelvic tilt angle (PT) (-11.62°±10.06° vs -7.04°±8.45°, P=0.046) and T1 pelvic angle(TPA)(-12.88°±11.23° vs -7.31°±9.55°, P=0.031)during surgery were significantly higher in MC group compared to the NMC group. In group R, the FI% of paraspinal muscles in each lumbar segment of patients with postoperative MC was higher than that in patients without MC (P<0.05). In the R and N groups, there was no significant difference inthe SCSA of the lumbar paravertebral muscles between patients with postoperative MC and those without MC at each level (all P>0.05). Multivariate logistic regression analysis showed that the average FI% of lumbar PSM was correlated with the occurrence of MC after spinal fusion in DS patients.The average FI% of lumbar PSM≥22.63% was a risk factors for MC after spinal fusion (P=0.010,OR=1.088, 95%CI:1.020-1.160). Conclusions: Female DS patients with higher degree of preoperative paraspinal muscle degeneration have a higher incidence of postoperative mechanical complications. For these patients,.there is still a higher risk of mechanical complications after surgery even if the ideal Roussouly classification is restored after surgery.

Doping effect on a two-electron silver nanocluster.

This study investigates the effects of metal addition and doping of a 2-electron silver superatom, [Ag10{S2P(OiPr)2}8] (Ag10). When Ag+ is added to Ag10 in THF solution, [Ag11{S2P(OiPr)2}8(OTf)] (Ag11) is rapidly formed almost quantitatively. When the same method is used with Cu+, a mixture of alloys, [CuxAg11-x{S2P(OiPr)2}8]+ (x = 1-3, CuxAg11-x), is obtained. In contrast, introducing Au+ to Ag10 leads to decomposition. The structural and compositional analysis of Ag11 was characterized by single-crystal X-ray diffraction (SCXRD), ESI-MS, NMR spectroscopy, and DFT calculations. While no crystal structure was obtained for CuxAg11-x, DFT calculations provide insights into potential sites for copper location. The absorption spectrum exhibits a notable blue shift in the low-energy band after copper doping, contrasting with that of the slight shift observed in 8-electron Cu-doped Ag nanoclusters. Ag11 and CuxAg11-x are strongly emissive at room temperature, and solvatochromism across different organic solvents is highlighted. This study underscores the profound influence of metal addition and doping on the structural and optical properties of silver nanoclusters, providing important contributions to understanding the nanoclusters and their photophysical behaviors.

A Silver Nanocluster Assembled by a Superatomic Building Unit.

A unique assembly of a two-electron superatom, [Ag10{S2P(OiPr)2}8], as a primary building unit in the construction of a supramolecule [Ag10{S2P(OiPr)2}8]2(µ-4,4'-bpy) through a 4,4'-bipyridine (4,4'-bpy) linker is reported. This approach is facilitated by an open site in the structure that allows for effective pairing. The assembled structure demonstrates a minimal solvatochromic shift across organic solvents with variable polarities, highlighting the influence of self-assembly on the photophysical properties of silver nanoclusters.

Hydride-doped coinage metal superatoms and their catalytic applications.

Superatomic constructs have been identified as a critical component of future technologies. The isolation of coinage metal superatoms relies on partially reducing metallic frameworks to accommodate the mixed valent state required to generate a superatom. Controlling this reduction requires careful consideration in reducing the agent, temperature, and the ligand that directs the self-assembly process. Hydride-based reducing agents dominate the synthetic wet chemical routes to coinage metal clusters. However, within this category, a unique subset of superatoms that retain a hydride/s within the nanocluster post-reduction have emerged. These stable constructs have only recently been characterized in the solid state and have highly unique structural features and properties. The difficulty in identifying the position of hydrides in electron-rich metallic constructs requires the combination and correlation of several analytical methods, including ESI-MS, NMR, SCXRD, and DFT. This text highlights the importance of NMR in detecting hydride environments in these superatomic systems. Added to the complexity of these systems is the dual nature of the hydride, which can act as metallic hydrogen in some cases, resulting in entirely different physical properties. This review includes all hydride-doped superatomic nanoclusters emphasizing synthesis, structure, and catalytic potential.

Diselenophosphate Ligands as a Surface Engineering Tool in PdH-Doped Silver Superatomic Nanoclusters.

The first hydride-doped Pd/Ag superatoms stabilized by selenolates are reported: [PdHAg19(dsep)12] [dsep = Se2P(OiPr)2] 1 and [PdHAg20(dsep)12]+ 2. 1 was derived from the targeted transformation of [PdHAg19(dtp)12] [dtp = S2P(OiPr)2] by ligand exchange, whereas 2 was obtained from the addition of trifluoroacetic acid to 1, resulting in a symmetric redistribution of the capping silver atoms. The transformations are all achieved while retaining an 8-electron superatomic configuration. VT-NMR attests to the good stability of the NCs in solution, and single-crystal X-ray diffraction reveals the crucial role that the interstitial hydride plays in directing the position of the capping silver atoms. The total structures are reported alongside their electronic and optical properties. 1 and 2 are phosphorescent with a lifetime of 73 and 84 µs at 77 K, respectively. The first antibacterial activity data for superatomic bimetallic Pd/Ag nanoclusters are also reported.

[Effect of different observations on evaluation of cosmetic shoulder balance in adolescent idiopathic scoliosis patients with thoracic curve].

Objective: To investigate the correlations between cosmetic and radiographic parameters of shoulder balance, as well as the variations in cosmetic shoulder balance observed from different perspectives, among patients with adolescent idiopathic scoliosis (AIS) characterized by thoracic curves. Methods: A total of 43 patients with thoracic curves treated from July to October in 2022 in Nanjing Drum Tower Hospital were recruited in this study. There were 9 males and 34 females with a mean age of (14.3±1.5) years. All participants underwent comprehensive radiographic assessments and were photographed both from posterior and anterior views, focusing on the shoulder region as well as a higher level (maintaining a consistent vertical distance of 180 cm from the ground). Six cosmetic parameters were measured on the photographs: shoulder angle(α1), axilla angle(α2), shoulder area index 1(SAI1), shoulder area index 2 (SAI2), inner shoulder height (SHi) and outer shoulder height (SHo). Eight radiographic parameters were measured on the radiographs: radiographic shoulder height difference (RSHD), first rib angle (FRA), clavicle-rib cage intersection (CRCI), coracoid process height (CPH), T1 tilt, clavicle angle(CA), clavicle chest cage angle difference (CCAD) and Cobb angle. Differences among bilateral cosmetic indicators from different perspectives were analyzed and compared, and their correlation with bilateral radiographic indicators was studied. Results: There was no significant differences between anterior cosmetic parameters and posterior cosmetic parameters at the same level of observation(all P>0.05). However, when observing SHi, SHo, α1, and α2 at the shoulder level, it became evident that they exhibited significantly higher values compared to the corresponding higher level on the same side of the patients' bodies. This contrast was observed in both the dorsal [SHo: (0.11±1.20) cm vs (-0.44±1.39) cm, P=0.005; SHi: (0.64±0.86) cm vs (0.32±0.56) cm, P=0.003; α1:-0.47°±2.27° vs -0.77°±2.49°, P=0.014; α2:-3.06°±3.23° vs -2.21°±3.03°, P=0.034] and ventral [SHo: (0.12±1.29) cm vs (-0.48±1.35) cm, P=0.007; SHi: (0.61±0.88) cm vs (0.30±0.59) cm, P=0.006; α1:-0.46°±2.18° vs -0.69°±2.35°, P=0.018; α2:-3.26°±3.12° vs -2.05°±2.97°, P=0.029] aspects of the patients. SHi and SHo were more sensitive to this difference of height. The correlation coefficients between radiographic parameters and cosmetic aspects at the shoulder level varied from 0.374 to 0.767. Similarly, the correlation coefficients between radiographic parameters and cosmetic factors at the higher level ranged from 0.273 to 0.579 (all P<0.05). Conclusions: The cosmetic parameters had significant difference between different perspective of observation, the cosmetic parameters are needed to be observed at the shoulder level in the evaluation of patients' shoulder balance.

Hydride-Containing Pt-doped Cu-rich Nanoclusters: Synthesis, Structure, and Electrocatalytic Hydrogen Evolution.

A structurally precise hydride-containing Pt-doped Cu-rich nanocluster [PtH2 Cu14 {S2 P(Oi Pr)2 }6 (CCPh)6 ] (1) has been synthesized. It consists of a bicapped icosahedral Cu14 cage that encapsulates a linear PtH2 unit. Upon the addition of two equivalents of CF3 COOH to 1, two hydrido clusters are isolated. These clusters are [PtHCu11 {S2 P(Oi Pr)2 }6 (CCPh)4 ] (2), which is a vertex-missing Cu11 cuboctahedron encaging a PtH moiety, and [PtH2 Cu11 {S2 P(Oi Pr)2 }6 (CCPh)3 ] (3), a distorted 3,3,4,4,4-pentacapped trigonal prismatic Cu11 cage enclosing a PtH2 unit. The electronic structure of 2, analyzed by Density Functional Theory, is a 2e superatom. The electrocatalytic activities of 1-3 for hydrogen evolution reaction (HER) were compared. Notably, Cluster 2 exhibited an exceptionally excellent HER activity within metal nanoclusters, with an onset potential of -0.03 V (at 10 mA cm-2 ), a Tafel slope of 39 mV dec-1 , and consistent HER activity throughout 3000 cycles in 0.5 M H2 SO4 . Our study suggests that the accessible central Pt site plays a crucial role in the remarkable HER activity and may provide valuable insights for establishing correlations between catalyst structure and HER activity.

Spin independence of the strongly enhanced effective mass in ultra-clean SiGe/Si/SiGe two-dimensional electron system.

The effective mass at the Fermi level is measured in the strongly interacting two-dimensional (2D) electron system in ultra-clean SiGe/Si/SiGe quantum wells in the low-temperature limit in tilted magnetic fields. At low electron densities, the effective mass is found to be strongly enhanced and independent of the degree of spin polarization, which indicates that the mass enhancement is not related to the electrons' spins. The observed effect turns out to be universal for silicon-based 2D electron systems, regardless of random potential, and cannot be explained by existing theories.

Locating Interstitial Hydrides in MH2@Cu14 (M = Cu, Ag) Clusters by Single-Crystal X-ray Diffraction.

Two structures, [Cu15H2(S2CNnBu2)6(C≡CPh)6][CuCl2] (1) and [AgH2Cu14{S2P(OiPr)2}6(C≡CPh)6][PF6] (2), are characterized by X-ray crystallography with high-quality single crystals. The position of interstitial hydrides can be accurately located. In addition, the refinement of the hydrides with anisotropic displacement parameters (ADPs) was successful. The distances between the central atom and copper atoms, as well as the distances within the metal cages surrounding the hydrides, are analyzed and compared with similar MH2@Cu14 (M = Cu, Ag, Pd) compounds. This work provides a thoughtful and accurate assessment of the considerations and challenges associated with anisotropic refinement for H atoms, particularly in X-ray data collection.

A heteroleptic fused bi-cuboctahedral Cu21S2 cluster.

A new dicationic cluster, [Cu21S2{S2CNnBu2}9(C2Ph)6]2+, where the Cu21S2 kernel consists of two S@Cu12 cuboctahedra sharing a triangular Cu3 face is reported. Its waist part is bridged by three dithiocarbamate ligands, each in a hexaconnective, hexametallic (µ3, µ3) coordination pattern, an unprecedented feature in Cu nanocluster chemistry.

Hydride Doping Effects on the Structure and Properties of Eight-Electron Rh/Ag Superatoms: The [RhHx@Ag21-x{S2P(OnPr)2}12] (x = 0-2) Series.

Three hitherto unknown eight-electron rhodium/silver alloy nanoclusters, [RhAg21{S2P(OnPr)2}12] (1), [RhHAg20{S2P(OnPr)2}12] (2), and [RhH2Ag19{S2P(OnPr)2}12] (3), have been isolated and fully characterized. Cluster 1 contains a regular Rh@Ag12 icosahedral core, whereas 2 and 3 exhibit distorted RhH@Ag12 and RhH2@Ag12 icosahedral cores. The single-crystal neutron structure of 2 located the encapsulated hydride at the center of an enlarged RhAg3 tetrahedron. A similar position was found by neutron diffraction for one of the hydrides in 3, whereas the other hydride is trigonally coordinated to Rh and an elongated Ag-Ag edge. The solid-state structures of 1-3 possess C1 symmetry due to the asymmetric arrangement of the surrounding capping Ag atoms. Our investigation shows that the insertion of one hydride dopant provokes the elimination of one capping silver atom on the cluster surface, resulting in the general formula [RhHx@Ag21-x{S2P(OnPr)2}12] (x = 0-2), which maintains the same number of cluster electrons as well as neutral charge. Clusters 1-3 exhibit an intense emission band in the NIR region. Contrarily to their PdAg21 and PdHAg20 relatives, the 4d orbitals of the encapsulated heterometal are somewhat involved in the optical processes.

Recent progress in dichalcophosphate coinage metal clusters and superatoms.

Atomically precise clusters of group 11 metals (Cu, Ag, and Au) attract considerable attention owing to their remarkable structure and fascinating properties. One of the unique subclasses of these clusters is based on dichalcophosphate ligands of [(RO)2PE2]- type (E = S or Se, and R = alkyl). These ligands successfully stabilise the most diverse Cu, Ag, and Au clusters and superatoms, spanning from simple ones to amazing assemblies featuring unusual structural and bonding patterns. It is noteworthy that such complicated clusters are assembled directly from cheap and simple reagents, metal(I) salts and dichalcophosphate anions. This reaction, when performed in the presence of a hydride or other anion sources, or foreign metal ions, results in hydrido- or anion-templated homo- or heteronuclear structures. In this feature article, we survey the recent advances in this exciting field, highlighting the powerful synthetic capabilities of the system "a metal(I) salt - [(RO)2PX2]- ligands - a templating anion or borohydride" as an inexhaustible platform for the creation of new atomically precise clusters, superatoms, and nanoalloys.

Galvanic replacement-induced introduction of a heteroligand into bimetallic and trimetallic nanoclusters.

Heteroleptic 8-electron silver-rich alloy nanoclusters, [Au@Au4Ag12(dtp)7(PPh3)4]2+ (1) and [Pt@Au4Ag11(dtp)7(PPh3)4] (2), were successfully synthesized via a galvanic replacement reaction of 1,1-dithiolate-protected M@Ag20 (M = Au and Pt) nanoclusters with Au(I)-phosphine salts, leading to the alteration of the cluster nuclearity and geometry of shell skeletons but retaining the same 8-electron count.

Controlled Shell and Kernel Modifications of Atomically Precise Pd/Ag Superatomic Nanoclusters.

The first 8-electron Pd/Ag superatomic alloys with an interstitial hydride [PdHAg19 (dtp)12 ] (dtp=S2 P(Oi Pr)2 - ) 1 and [PdHAg20 (dtp)12 ]+ 2 are reported. The targeted addition of a single Ag atom to 1 is achieved by the reaction of one equivalent of trifluoroacetic acid, resulting in the formation of 2 in 55 % yield. Further modification of the shell results in the formation of [PdAg21 (dtp)12 ]+ 3 via an internal redox reaction, with the system retaining an 8-electron superatomic configuration. The interstitial hydride in 1 and 2 contributes its 1s1 electron to the superatomic electron count and occupies a PdAg3 tetrahedron. The distributions of isomers corresponding to different dispositions of the outer capping Ag atoms are investigated by multinuclear VT NMR spectroscopy. The emissive state of 3 has a lifetime of 200 µs (λex =448; λem =842), while 1 and 2 are non-emissive. The catalytic reduction of 4-nitrophenol is demonstrated with 1-3 at room temperature.

Hydride-containing 2-Electron Pd/Cu Superatoms as Catalysts for Efficient Electrochemical Hydrogen Evolution.

The first hydride-containing 2-electron palladium/copper alloys, [PdHCu11 {S2 P(Oi Pr)2 }6 (C≡CPh)4 ] (PdHCu11 ) and [PdHCu12 {S2 P(Oi Pr)2 }5 {S2 PO(Oi Pr)} (C≡CPh)4 ] (PdHCu12 ), are synthesized from the reaction of [PdH2 Cu14 {S2 P(Oi Pr)2 }6 (C≡CPh)6 ] (PdH2 Cu14 ) with trifluoroacetic acid (TFA). X-ray diffraction reveals that the PdHCu11 and PdHCu12 kernels consist of a central PdH unit encapsulated within a vertex-missing Cu11 cuboctahedron and complete Cu12 cuboctahedron, respectively. DFT calculations indicate that both PdHCu11 and PdHCu12 can be considered as axially-distorted 2-electron superatoms. PdHCu11 shows excellent HER activity, unprecedented within metal nanoclusters, with an onset potential of -0.05 V (at 10 mA cm-2 ), a Tafel slope of 40 mV dec-1 , and consistent HER activity during 1000 cycles in 0.5 M H2 SO4 . Our study suggests that the accessible central Pd site is the key to HER activity and may provide guidelines for correlating catalyst structures and HER activity.

Unusual core engineering on a copper hydride nanoball.

A neutral polyhydrido copper cluster, [Cu27H15{S2CNnBu2}12] (abbreviated as [Cu27H15]), was prepared by the reaction of dithiocarbamates (dtc), Cu(I) salts and NaBH4. The isolated cluster provides insights into core engineering, demonstrating its novel ability to reversibly add or remove one copper atom from the cluster core. Single-crystal X-ray analysis reveals that the new core-shell structure exhibits a Cu24 rhombicuboctahedral outer cage and an inner Cu3 triangular kernel. The two core-shell clusters, [Cu27H15{S2CNnBu2}12] and previously published [Cu28H15(S2CNnBu2)12]+ (abbreviated as [Cu28H15]+), are only differentiated by one copper atom in their inner core. Importantly, we demonstrate core engineering with the controllable reversible transition between an irregular Cu4 tetrahedron and a Cu3 triangle, whilst maintaining their outer Cu24 shell intact. The 15 hydride atoms in [Cu27H15], coordinated in three different modes, are co-incident with the hydride positions in [Cu28H15]+. The degradation of [Cu27H15] in solution or the addition of one eq. of Cu(I) ions leads to the conversion of [Cu27H15] into [Cu28H15]+, while the reverse transformation can be achieved by the addition of either formic acid or a reducing agent to [Cu28H15]+. A dicationic species was observed in the ESI mass spectrum, and the composition is formulated as [Cu56H30(S2CNnBu2)24]2+, a dimer of [Cu27H15(S2CNnBu2)12 + Cu+]22+. The dimeric species was further explored by DFT calculations, suggesting that the lowest energy structure consists of a [Cu28H15]+ and a [Cu27H15] cluster connected through one Cu+ atom bridge. As a result, [Cu27H15] is considered an intermediate species in the formation of the more stable [Cu28H15]+ nanoball.

Superatom Pruning by Diphosphine Ligands as a Chemical Scissor.

A two-electron silver superatom, [Ag6{S2P(OiPr)2}4(dppm)2] (1), was synthesized by adding dppm (bis(diphenylphosphino)methane) into [Ag20{S2P(OiPr)2}12] (8e). It was characterized by single-crystal crystallography, multinuclear NMR spectroscopy, electrospray ionization-mass spectrometry, density functional theory (DFT), and time-dependent DFT calculations. The added dppm ligands, which carry out the nanocluster-to-nanocluster transformation, act as a chemical scissor to prune the nanocluster geometrically from an icosahedron-based Ag20 nanocluster (NC) to an octahedral Ag6 NC and electronically from eight-electron to two-electron. Eventually, dppm was involved in the protective shell to form a new heteroleptic NC. The temperature-dependent NMR spectroscopy confirms its fluxional behavior, showing the fast atomic movement at ambient temperature. Compound 1 exhibits a bright yellow emission under UV irradiation at ambient temperature with a quantum yield of 16.3%. This work demonstrates a new methodology to achieve nanocluster-to-nanocluster transformation via stepwise synthesis.

Synthesis, structural studies, and photophysical properties of heteroleptic inverse-coordination clusters.

Two series of hyper-coordinated halide-centered M12 cuboctahedral clusters, [M12(µ12-X){S2P(OnPr)2}6{CCPh}4](PF6), 1a-c and 2a-c (where M = Cu, 1; Ag, 2; X = Cl, a; Br, b; I, c), were synthesized and fully characterized by ESI-MS, multi-NMR spectroscopy, IR and UV-Vis spectroscopy, photoluminescence analysis, and single-crystal X-ray crystallography. Structures 1c, 2b, and 2c show a twelve-coordinated halide encapsulated in the M12 cage, which is stabilized by six dithiophosphate and four alkynyl ligands. Compound 2b is the first Ag(I) cluster containing a twelve-coordinated bromide. The structural features of all six clusters are highly similar, providing a comparison basis of the inverse coordination for halides. Besides, the detailed structural analysis illustrates how the inverse coordination of a halide has influenced the size of the cuboctahedral M12 framework.