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BeTaOs2 crystallizes in the orthorhombic Immm space group. The structure is one-dimensional and consists of two BeTaOs2 ribbons oriented in the (1, 0, 0) direction. Be is bonded in a linear geometry to two equivalent Os atoms. Both Be–Os bond lengths are 2.25 Å. Ta is bonded in a linear geometry to two equivalent Os atoms. Both Ta–Os bond lengths are 2.24 Å. Os is bonded in a linear geometry to one Be and one Ta atom.
Tm3Os4Ge13 crystallizes in the cubic Pm-3n space group. The structure is three-dimensional. Tm is bonded in a 8-coordinate geometry to four equivalent Os and twelve equivalent Ge atoms. All Tm–Os bond lengths are 3.20 Å. There are eight shorter (3.18 Å) and four longer (3.24 Å) Tm–Ge bond lengths. Os is bonded in a 6-coordinate geometry to three equivalent Tm and six equivalent Ge atoms. All Os–Ge bond lengths are 2.50 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 2-coordinate geometry to three equivalent Tm, two equivalent Os, and one Ge atom. The Ge–Ge bond length is 3.02 Å. In the second Ge site, Ge is bonded in a cuboctahedral geometry to twelve equivalent Ge atoms.
Th3Os4Sn13 crystallizes in the cubic Pm-3n space group. The structure is three-dimensional. Th is bonded in a 12-coordinate geometry to four equivalent Os and twelve equivalent Sn atoms. All Th–Os bond lengths are 3.47 Å. All Th–Sn bond lengths are 3.46 Å. Os is bonded in a 6-coordinate geometry to three equivalent Th and six equivalent Sn atoms. All Os–Sn bond lengths are 2.69 Å. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded in a 2-coordinate geometry to three equivalent Th, two equivalent Os, and one Sn atom. The Sn–Sn bond length is 3.35 Å. In the second Sn site, Sn is bonded in a cuboctahedral geometry to twelve equivalent Sn atoms.
TmOsGa3 crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Tm is bonded in a 8-coordinate geometry to four equivalent Os and ten Ga atoms. All Tm–Os bond lengths are 3.20 Å. There are eight shorter (2.93 Å) and two longer (3.20 Å) Tm–Ga bond lengths. Os is bonded to four equivalent Tm and eight equivalent Ga atoms to form distorted OsTm4Ga8 cuboctahedra that share corners with four equivalent OsTm4Ga8 cuboctahedra, edges with four equivalent GaTm6 octahedra, and faces with eight equivalent OsTm4Ga8 cuboctahedra. All Os–Ga bond lengths are 2.66 Å. There are two inequivalent Ga sites. In the first Ga site, Ga is bonded to six equivalent Tm atoms to form GaTm6 octahedra that share corners with six equivalent GaTm6 octahedra and edges with twelve equivalent OsTm4Ga8 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. In the second Ga site, Ga is bonded in a 6-coordinate geometry to three equivalent Tm and three equivalent Os atoms.
HoOs2SiC crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Ho3+ is bonded in a distorted rectangular see-saw-like geometry to four equivalent C4- atoms. All Ho–C bond lengths are 2.67 Å. Os+1.50- is bonded in a 4-coordinate geometry to three equivalent Si4+ and one C4- atom. All Os–Si bond lengths are 2.48 Å. The Os–C bond length is 1.88 Å. Si4+ is bonded in a 6-coordinate geometry to six equivalent Os+1.50- atoms. C4- is bonded to four equivalent Ho3+ and two equivalent Os+1.50- atoms to form a mixture of edge and corner-sharing CHo4Os2 octahedra. The corner-sharing octahedral tilt angles are 22°.
Ti2VOs is Heusler structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Ti is bonded in a distorted body-centered cubic geometry to four equivalent V and four equivalent Os atoms. All Ti–V bond lengths are 2.70 Å. All Ti–Os bond lengths are 2.70 Å. V is bonded in a 8-coordinate geometry to eight equivalent Ti and six equivalent Os atoms. All V–Os bond lengths are 3.12 Å. Os is bonded in a distorted body-centered cubic geometry to eight equivalent Ti and six equivalent V atoms.
K3Os is alpha bismuth trifluoride structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. there are two inequivalent K sites. In the first K site, K is bonded to four equivalent K and four equivalent Os atoms to form a mixture of distorted face, edge, and corner-sharing KK4Os4 tetrahedra. All K–K bond lengths are 3.59 Å. All K–Os bond lengths are 3.59 Å. In the second K site, K is bonded in a 8-coordinate geometry to eight equivalent K and six equivalent Os atoms. All K–Os bond lengths are 4.14 Å. Os is bonded in a body-centered cubic geometry to fourteen K atoms.
Y3Os4Ge13 crystallizes in the cubic Pm-3n space group. The structure is three-dimensional. Y is bonded in a 8-coordinate geometry to four equivalent Os and twelve equivalent Ge atoms. All Y–Os bond lengths are 3.22 Å. There are eight shorter (3.21 Å) and four longer (3.25 Å) Y–Ge bond lengths. Os is bonded in a 6-coordinate geometry to three equivalent Y and six equivalent Ge atoms. All Os–Ge bond lengths are 2.50 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 2-coordinate geometry to three equivalent Y, two equivalent Os, and one Ge atom. The Ge–Ge bond length is 3.02 Å. In the second Ge site, Ge is bonded in a cuboctahedral geometry to twelve equivalent Ge atoms.
MgEr2Os is Heusler structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Mg is bonded in a distorted body-centered cubic geometry to eight equivalent Er and six equivalent Os atoms. All Mg–Er bond lengths are 3.04 Å. All Mg–Os bond lengths are 3.51 Å. Er is bonded in a distorted body-centered cubic geometry to four equivalent Mg and four equivalent Os atoms. All Er–Os bond lengths are 3.04 Å. Os is bonded in a body-centered cubic geometry to six equivalent Mg and eight equivalent Er atoms.
ThHoOs2 is Heusler structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Th is bonded in a body-centered cubic geometry to eight equivalent Os atoms. All Th–Os bond lengths are 3.02 Å. Ho is bonded in a body-centered cubic geometry to eight equivalent Os atoms. All Ho–Os bond lengths are 3.02 Å. Os is bonded in a body-centered cubic geometry to four equivalent Th and four equivalent Ho atoms.
Er3Os4Si13 crystallizes in the cubic Pm-3n space group. The structure is three-dimensional. Er3+ is bonded in a 12-coordinate geometry to four equivalent Os+1.25- and twelve equivalent Si+0.31- atoms. All Er–Os bond lengths are 3.11 Å. There are eight shorter (3.16 Å) and four longer (3.21 Å) Er–Si bond lengths. Os+1.25- is bonded in a 6-coordinate geometry to three equivalent Er3+ and six equivalent Si+0.31- atoms. All Os–Si bond lengths are 2.43 Å. There are two inequivalent Si+0.31- sites. In the first Si+0.31- site, Si+0.31- is bonded in a 2-coordinate geometry to three equivalent Er3+, two equivalent Os+1.25-, and one Si+0.31- atom. The Si–Si bond length is 2.76 Å. In the second Si+0.31- site, Si+0.31- is bonded in a cuboctahedral geometry to twelve equivalent Si+0.31- atoms.
Clinical trials have demonstrated the benefit of PD-1/PD-L1 blocking antibodies for the treatment of patients with advanced non-small cell lung cancer (NSCLC) in defined patient populations that often exclude patients with moderate or severe hepatic or renal impairment. We assessed the association between overall survival (OS) and baseline organ function in patients with advanced NSCLC treated with PD-1/PD-L1 blocking antibodies in real-world data (RWD; patient-level data from electronic health records) and pooled clinical trial data submitted to the US Food and Drug Administration (FDA). The Kaplan–Meier estimator was used to estimate OS in different subgroups based on organ function. Unadjusted and adjusted Cox proportional hazards models were used to estimate the association between OS and organ function. In this hypothesis-generating study, baseline renal impairment did not appear to be associated with OS, while patients with baseline liver impairment had shorter OS. RWD provided information on a broader range of renal and hepatic function than was evaluated in clinical trials and hold promise to complement trial data in better understanding populations not represented in clinical trials.
BACKGROUND:We previously established a 53-gene prognostic signature for overall survival (OS) of gastric cancer patients. This retrospective multi-center study aimed to develop a clinically applicable gene expression detection assay and to investigate the prognostic value of this signature. METHODS:A TCGA gastric adenocarcinoma cohort (TCGA-STAD) was used for comparing 53-gene signature with other gene signatures. A high-throughput mRNA hybridization gene expression assay was developed to quantify the expression of 53-genes in formalin-fixed paraffin-embedded tissues of 540 patients enrolled from three hospitals. 180 patents were randomly selected from two hospitals to build a prognostic prediction model based on the 53-gene signature using leave-p-out (one-third out) cross-validation method together with Cox regression and Kaplan-Meier analysis, and the model was assessed on three validation cohorts. FINDINGS:In the evaluation phase, studies based on TCGA-STAD showed that the 53-gene signature was significantly superior to other three prognostic signatures and was independent of TCGA molecular subtypes and clinical factors. For clinical validation and utility, the prognostic scores were generated using the newly developed assay, which was reliable and sensitive, in 100 sampling training sets and were significantly associated with OS in 100 sampling validation sets. The scores were significantly associated with OS in three independent and combined validation cohorts, and in patients with stages II and III/IV. The multivariate Cox regression demonstrated that the prognostic power of the score was independent of clinical factors, consistent with those findings in the TCGA dataset. Finally, patients with good prognostic scores exhibited significantly a better 5-year OS rate from adjuvant FOLFOX chemotherapy after surgery than from other chemotherapies. INTERPRETATION:The 53-gene prognostic score system is clinically applicable for predicting the OS of patients independent of clinical factors in gastric cancers, which could also be a promising predictive biomarker for FOLFOX regimen. FUNDING:Chinese National Science and Technology, National Natural Science Foundation and Natural Science Foundation of Jiangsu Province.
The crystal chemistry and magnetism of compositions in the Sr 2-x Ba x NiOsO 6 phase diagram have been investigated to better understand the superexchange interactions between 3d and 5d transition metal ions. Compositions with x < 1.35 crystallize with the double perovskite structure, while those with x > 1.83 crystallize in a trigonal structure that is a cation ordered variant of the 6H hexagonal perovskite structure. The Sr-rich double perovskites undergo a cubic to tetragonal distortion upon cooling that is driven by out-of-phase octahedral tilting. The tetragonal distortion occurs upon cooling below 650 K in Sr 2 NiOsO 6 . The temperature of this transition decreases as the barium content increases and is completely suppressed for x ≥ 1.2. All compositions in the double perovskite region become spin glasses below T g ≈ 40 K, due to the competition between ferromagnetic Ni–Os and antiferromagnetic Ni–Ni and Os–Os superexchange interactions. The double perovskite compositions that are rich in barium, like Sr 0.8 Ba 1.2 NiOsO 6 show some signs of magnetic ordering in small clusters, but the presence of Ba/Sr disorder inhibits long-range magnetic order. Trigonal Ba 2 NiOsO 6 orders ferrimagnetically below T C = 108 K. In conclusion, the magnetic structure of this compound contains ferromagnetic ~180° Ni–O–Os interactions and antiferromagnetic ~90° Ni–O–Os interactions, both in agreement with the Goodenough-Kanamori rules.
An Os(II) polypyridyl complex was applied as a photosensitizer in dye-sensitized photocatalyst systems based on Pt-intercalated HCa 2 Nb 3 O 10 and Pt-loaded TiO 2 . The Os(II) complex exhibits a spin-forbidden but partially allowed triplet metal-to-ligand charge transfer ( 3 MLCT) transition, enabling broad visible light absorption up to 800 nm, which surpasses that of conventional Ru(II)-based dyes. Despite its shorter excited-state lifetime compared to Ru(II) complexes, efficient electron injection from the excited Os(II) dye into the semiconductor was confirmed. Under visible-light irradiation, the Os(II)- sensitized photocatalysts showed higher H 2 evolution activity than the Ru(II)-sensitized photocatalysts when sodium ascorbate was used as an electron donor, demonstrating effective utilization of long-wavelength visible light. In contrast, negligible H 2 evolution was observed when NaI was employed as a redox mediator for Z-scheme water splitting. Transient absorption spectroscopy revealed that the lack of activity stemmed from inefficient electron transfer from I − to oxidized Os(II). These findings highlight the importance of selecting appropriate redox mediators to fully exploit long-wavelength dyes for overall water splitting under visible light.
Two osmium(II) photocatalysts bearing a dicationic 4,4'-bis-(trimethylaminomethyl)-2,2'-bipyridine (tmam) ligand and 2,2'-bipyridine {[Os(bpy) 2 (tmam)] 4+ } or 4,4'-(CF 3 ) 2 -2,2'-bipyridine {[Os((CF3)2bpy) 2 (tmam)] 4+ } ancillary ligands were synthesized and characterized for application in HX splitting. Iodide titration studies in acetone solutions provided evidence for an in situ formed terionic complex with two iodide ions as evidenced by 1H NMR and UV-visible absorption spectroscopies, as well as by density functional theory calculations and natural bond order analysis. The photocatalyst [Os(bpy)2(tmam)] 4+ was shown to be inefficient in iodide oxidation. In contrast, visible light excitation of [Os((CF3)2bpy)2(tmam)]4+ led to rapid iodide oxidation, kq = 2.8 × 1011 M-1 s-1. The data reveal that Os(II) photocatalysts can be fine-tuned for application in HX splitting.
Microbial mats are stratified communities often dominated by unicellular and filamentous phototrophs within an exopolymer matrix. It is challenging to quantify the dynamic responses of community members in situ as they experience steep gradients and rapid fluctuations of light. To address this, we developed a binary consortium using two representative isolates from hot spring mats: the unicellular oxygenic phototrophic cyanobacterium Synechococcus OS-B′ (Syn OS-B′) and the filamentous anoxygenic phototroph Chloroflexus MS-CIW-1 (Chfl MS-1). We quantified the motility of individual cells and entire colonies and demonstrated that Chfl MS-1 formed bundles of filaments that moved in all directions with no directional bias to light. Syn OS-B′ was slightly less motile but exhibited positive phototaxis. This binary consortium displayed cooperative behavior by moving further than either species alone and formed ordered arrays where both species aligned with the light source. No cooperative motility was observed when a nonmotile pilB mutant of Syn OS-B′ was used instead of Syn OS-B′. The binary consortium also produced more adherent biofilm than individual species, consistent with the close interspecies association revealed by electron microscopy. We propose that cyanobacteria and Chloroflexota cooperate in forming natural microbial mats by colonizing new niches and building robust biofilms.
Optical microscopy, owing to its noninvasiveness and subcellular resolution, enables in vivo visualization of neuronal structure and function in the physiological context. Optical-sectioning structured illumination microscopy (OS-SIM) is a widefield fluorescence imaging technique that uses structured illumination patterns to encode in-focus structures and optically sections 3D samples. However, its application to in vivo imaging has been limited. In this study, we optimized OS-SIM for in vivo neural imaging. We modified OS-SIM reconstruction algorithms to improve signal-to-noise ratio and correct motion-induced artifacts in live samples. Incorporating an adaptive optics (AO) module to OS-SIM, we found that correcting sample-induced optical aberrations was essential for achieving accurate structural and functional characterizations in vivo. With AO OS-SIM, we demonstrated fast, high-resolution in vivo imaging with optical sectioning for structural imaging of mouse cortical neurons and zebrafish larval motor neurons, and functional imaging of quantal synaptic transmission at Drosophila larval neuromuscular junctions.