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1.
J Colloid Interface Sci ; 678(Pt C): 959-967, 2025 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-39326167

RESUMO

This study demonstrates the preparation of needle-like Ce-MOF crystals on molybdenum disulfide (MoS2) nanosheets using in-situ growth technology. This hybrid structure significantly enhances the thermal management and mechanical properties of thermosetting epoxy resin (EP). Specifically, EP/Ce-MOF@MoS2-3 exhibits a notable increase in tensile strength (TS) to 50.87 MPa and elongation at break (EB) to 10.84 %. Moreover, Ce-MOF@MoS2 provides synergistic flame retardant benefits, reducing the peak heat release rate (pHRR) and total heat release (THR) of EP/Ce-MOF@MoS2-3 by 38 % and 12.64 %, respectively, compared to EP-0. Additionally, Ce-MOF@MoS2 suppresses smoke and reduces toxic emissions; at a 3 % loading, it decreases CO and CO2 production in EP nanocomposites by 48.8 % and 38.7 %, respectively. Thus, this Ce-MOF@MoS2 hybrid, synthesized via in-situ growth, offers a novel approach for developing EP nanocomposites with superior thermal management and mechanical properties, along with effective flame retardancy and reduced hazardous emissions during thermal events.

2.
Front Immunol ; 15: 1439413, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39483484

RESUMO

Tertiary Lymphoid Structures (TLS) are organized aggregates of immune cells such as T cells, B cells, and Dendritic Cells (DCs), as well as fibroblasts, formed postnatally in response to signals from cytokines and chemokines. Central to the function of TLS are DCs, professional antigen-presenting cells (APCs) that coordinate the adaptive immune response, and which can be classified into different subsets, with specific functions, and markers. In this article, we review current data on the contribution of different DC subsets to TLS function in cancer and autoimmunity, two opposite sides of the immune response. Different DC subsets can be found in different tumor types, correlating with cancer prognosis. Moreover, DCs are also present in TLS found in autoimmune and inflammatory conditions, contributing to disease development. Broadly, the presence of DCs in TLS appears to be associated with favorable clinical outcomes in cancer while in autoimmune pathologies these cells are associated with unfavorable prognosis. Therefore, it is important to analyze the complex functions of DCs within TLS in order to enhance our fundamental understanding of immune regulation but also as a possible route to create innovative clinical interventions designed for the specific needs of patients with diverse pathological diseases.


Assuntos
Doenças Autoimunes , Células Dendríticas , Neoplasias , Estruturas Linfoides Terciárias , Humanos , Células Dendríticas/imunologia , Neoplasias/imunologia , Neoplasias/patologia , Estruturas Linfoides Terciárias/imunologia , Estruturas Linfoides Terciárias/patologia , Doenças Autoimunes/imunologia , Animais , Autoimunidade
3.
Sci Rep ; 14(1): 26240, 2024 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-39482344

RESUMO

This paper discusses the seismic performance of five reduced-scale shear walls, including one cast-in-place (CIP) concrete shear wall, two precast concrete (PC) shear walls with overlapping U-bar loop connections, and two PC shear walls with modified form-overlapping U-bar loop connections combined with extruded sleeve connections. A quasi-static test was conducted to evaluate the reliability of the overlapping U-bar loop connections and the modified form by comparing the corresponding mechanical parameters of PC specimens with those of the CIP specimen. Moreover, the differences in seismic performance between the CIP specimen and PC specimens with different connection methods were also analyzed in terms of damage process, hysteretic loops and skeleton curves, load carrying capacity, ductility, equivalent stiffness, and energy dissipation. The experimental findings indicated that the mechanical performances of PC specimens with the modified connection form outperformed those of PC specimens with pure overlapping U-bar loop connections, closely resembling the properties of cast-in-place specimens; the failure mode of PC specimens was consistent with that of the CIP specimen; the generation, distribution and development of cracks in PC specimens were also similar to those in the CIP specimen. Furthermore, although the load-bearing capacity and peak displacement of PC specimens were lower than those of the CIP specimen due to the failure of the post-casted concrete strength to meet the requirements, the ductility, equivalent stiffness, and energy dissipation of PC specimens with the modified connection form closely matched that of the CIP specimen.

4.
Mol Immunol ; 175: 143-145, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39383568

RESUMO

The immune make-up of human tumors is dynamic over the course of cancer progression. However, what factors drive spatiotemporal changes in the tumor-immune landscape is not well-known. In issue 3 of Cell Reports Medicine, Liu, You, Lan and Ren et al. demonstrate that the development of tertiary lymphoid structures (TLSs) is a stepwise process that co-occurs with tumor progression in patients with lung adenocarcinoma (LUAD).

5.
J Biomech ; 176: 112362, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39383689

RESUMO

This study explores the effectiveness of architected lattice structures, specifically made of polyamide 12 (PA12) material, as potential helmet liners to mitigate traumatic brain injuries (TBI), with a focus on rotational acceleration. Evaluating three lattice unit cell topologies (simple cubic, dode-medium, and rhombic dodecahedron), the research builds upon prior investigations indicating that PA12 lattice liners may outperform conventional EPS liners. Employing a high-fidelity finite element male head model and utilizing direct and oblique impact scenarios, mechanical quantities, such as maximum principal strain (MPS) and shear strain, cumulative strain damage measure and intracranial pressure were measured at the tissue level in different brain regions. Results indicate that lattice liners, especially with dode-medium topology, exhibit promising reductions in brain tissue strains. On average, during oblique impacts, less than 1 % of the brain volume experienced an MPS level of 0.4 when the lattice liners were adopted, whereas that percentage was above 70 % with the expandable polystyrene (EPS) foam liners. Pressure-based assessments suggest that lattice liners may outperform EPS liners in oblique impacts, showcasing the limitations of EPS for effective TBI mitigation. Despite certain model limitations, this study emphasizes the need for advancements in helmet technology, particularly in the development of commercial lattice liners using additive manufacturing, to address the limitations of existing EPS liners in preventing rotational consequences of impacts and reducing TBI.

6.
Trends Cancer ; 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39353814

RESUMO

The impact of tumor-infiltrating B cells on breast cancer (BRCA) outcomes remains poorly understood. Recent findings from Yang et al. identify an atypical, clonally expanded population of activated Fc receptor-like 4 (FCRL4)+ B cells that is associated with improved overall survival in patients affected by various tumor types, including BRCA.

7.
Angew Chem Int Ed Engl ; : e202414360, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39353849

RESUMO

Tin-oxo clusters are increasingly recognized as promising materials for nanolithography technology due to their unique properties, yet their structural impacts on lithography performance remain underexplored. This work explores the structural impacts of heterometal strategies on the performance of tin-oxo clusters in nanolithography, focusing on various metal dopants and their coordination geometries. Specifically, SnOC-1(In), SnOC-1(Al), SnOC-1(Fe), and SnOC-2 were synthesized and characterized. These clusters demonstrate excellent solubility, dispersibility, and stability, facilitating the preparation of high-quality films via spin-coating for lithographic applications. Notably, this work innovatively employs nano-infrared (nano-IR), neutron reflectivity (NR), and X-ray reflectivity (XRR) measurements to confirm film homogeneity. Upon electron beam lithography (EBL), all four materials achieve 50 nm line patterns, with SnOC-1(In) demonstrating the highest lithography sensitivity. This enhanced sensitivity is attributed to indium dopants, which possess superior EUV absorption capabilities and unsaturated coordination environments. Further studies on exposure mechanisms indicated that Sn-C bond cleavage generates butyl free radicals, promoting network formations that induce solubility-switching behaviors for lithography. These findings underscore the efficacy of tailored structural design and modulation of cluster materials through heterometal strategies in enhancing lithography performance, offering valuable insights for future material design and applications.

8.
Pharmacol Res ; : 107438, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39357691

RESUMO

The toxicity of tacrolimus metabolites and their potential pharmacodynamic (PD) interactions with tacrolimus might respectively explain the surprising combination of higher toxicity and lower efficacy of tacrolimus despite normal blood concentrations, described in extensive metabolizers. To evaluate such interactions, we produced tacrolimus metabolites in vitro and characterized them by high resolution mass spectrometry (HRMS, for all) and nuclear magnetic resonance (NMR, for the most abundant, M-I). We quantified tacrolimus metabolites and checked their structure in patient whole blood and peripheral blood mononuclear cells (PBMC). We explored the interactions of M-I with tacrolimus in silico, in vitro and ex vivo. In vitro metabolization produced isoforms of tacrolimus and of its metabolites M-I and M-III, whose HRMS fragmentation suggested an open-ring structure. M-I and M-III open-ring isomers were also observed in patient blood. By contrast, NMR could not detect these open-ring forms. Transplant patients expressing CYP3A5 exhibited higher M-I/TAC ratios in blood and PBMC than non-expressers. Molecular Dynamics simulations showed that: all possible tacrolimus metabolites and isomers bind FKPB12; and the hypothetical open-ring structures induce looser binding between FKBP12 and calcineurins, leading to lower CN inhibition. In vitro, tacrolimus bound FKPB12 with more affinity than purified M-I, and the pool of tacrolimus metabolites and purified M-I had only weak inhibitory activity on IL2 secretion and not at all on NFAT nuclear translocation. M-I showed no competitive effect with tacrolimus on either test. Finally, M-I or the metabolite pool did not significantly interact with tacrolimus MLR suppression, thus eliminating a pharmacodynamic interaction.

9.
Geom Dedic ; 218(5): 102, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39360030

RESUMO

We consider the existence of cohomogeneity one solitons for the isometric flow of G 2 -structures on the following classes of torsion-free G 2 -manifolds: the Euclidean R 7 with its standard G 2 -structure, metric cylinders over Calabi-Yau 3-folds, metric cones over nearly Kähler 6-manifolds, and the Bryant-Salamon G 2 -manifolds. In all cases we establish existence of global solutions to the isometric soliton equations, and determine the asymptotic behaviour of the torsion. In particular, existence of shrinking isometric solitons on R 7 is proved, giving support to the likely existence of type I singularities for the isometric flow. In each case, the study of the soliton equation reduces to a particular nonlinear ODE with a regular singular point, for which we provide a careful analysis. Finally, to simplify the derivation of the relevant equations in each case, we first establish several useful Riemannian geometric formulas for a general class of cohomogeneity one metrics on total spaces of vector bundles which should have much wider application, as such metrics arise often as explicit examples of special holonomy metrics.

10.
Proteomics ; : e202400210, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39361250

RESUMO

N-Linked glycosylation is crucial for various biological processes such as protein folding, immune response, and cellular transport. Traditional experimental methods for determining N-linked glycosylation sites entail substantial time and labor investment, which has led to the development of computational approaches as a more efficient alternative. However, due to the limited availability of 3D structural data, existing prediction methods often struggle to fully utilize structural information and fall short in integrating sequence and structural information effectively. Motivated by the progress of protein pretrained language models (pLMs) and the breakthrough in protein structure prediction, we introduced a high-accuracy model called CoNglyPred. Having compared various pLMs, we opt for the large-scale pLM ESM-2 to extract sequence embeddings, thus mitigating certain limitations associated with manual feature extraction. Meanwhile, our approach employs a graph transformer network to process the 3D protein structures predicted by AlphaFold2. The final graph output and ESM-2 embedding are intricately integrated through a co-attention mechanism. Among a series of comprehensive experiments on the independent test dataset, CoNglyPred outperforms state-of-the-art models and demonstrates exceptional performance in case study. In addition, we are the first to report the uncertainty of N-linked glycosylation predictors using expected calibration error and expected uncertainty calibration error.

11.
Front Immunol ; 15: 1422206, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39376565

RESUMO

Tertiary Lymphoid Structures (TLS) are lymphoid structures commonly associated with improved survival of cancer patients and response to immunotherapies. However, conflicting reports underscore the need to consider TLS heterogeneity and multiple features such as TLS size, composition, and maturation status, when assessing their functional impact. With the aim of gaining insights into TLS biology and evaluating the prognostic impact of TLS maturity in Non-Small Cell Lung Carcinoma (NSCLC), we developed a multiplex immunofluorescent (mIF) panel including T cell (CD3, CD8), B cell (CD20), Follicular Dendritic cell (FDC) (CD21, CD23) and mature dendritic cell (DC-LAMP) markers. We deployed this panel across a cohort of primary tumor resections from NSCLC patients (N=406) and established a mIF image analysis workstream to specifically detect TLS structures and evaluate the density of each cell phenotype. We assessed the prognostic significance of TLS size, number, and composition, to develop a TLS scoring system representative of TLS biology within a tumor. TLS relative area, (total TLS area divided by the total tumor area), was the most prognostic TLS feature (C-index: 0.54, p = 0.04). CD21 positivity was a marker driving the favorable prognostic impact, where CD21+ CD23- B cells (C-index: 0.57, p = 0.04) and CD21+ CD23- FDC (C-index: 0.58, p = 0.01) were the only prognostic cell phenotypes in TLS. Combining the three most robust prognostic TLS features: TLS relative area, the density of B cells, and FDC CD21+ CD23- we generated a TLS scoring system that demonstrated strong prognostic value in NSCLC when considering the effect of age, sex, histology, and smoking status. This TLS Score also demonstrated significant association with Immunoscore, EGFR mutational status and gene expression-based B-cell and TLS signature scores. It was not correlated with PD-L1 status in tumor cells or immune cells. In conclusion, we generated a prognostic TLS Score representative of the TLS heterogeneity and maturity undergoing within NSCLC tissues. This score could be used as a tool to explore how TLS presence and maturity impact the organization of the tumor microenvironment and support the discovery of spatial biomarker surrogates of TLS maturity, that could be used in the clinic.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Estruturas Linfoides Terciárias , Humanos , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Estruturas Linfoides Terciárias/imunologia , Estruturas Linfoides Terciárias/patologia , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/mortalidade , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Prognóstico , Microambiente Tumoral/imunologia , Biomarcadores Tumorais , Adulto , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Idoso de 80 Anos ou mais
12.
Ultrasonics ; 145: 107467, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39378774

RESUMO

Limited information exists on the ability of nondestructive testing techniques to detect, size, and characterize flaws in existing hydraulic steel structures (HSS). Round robin experiments were conducted using phased array ultrasonics to inspect welded steel specimens representing joints in existing HSS. Technicians detected 83% of the flaws scanned, but detection rates varied widely by flaw and technician. Uncertainty in flaw size estimates, represented by 90% confidence bounds on the ratio of estimated to actual length or height, ranged from 0.52 to 2.10 for length and 0.32 to 3.59 for height. Planar, volumetric and laminar flaws were accurately characterized 80% of the time.

13.
R Soc Open Sci ; 11(10): 240957, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39359462

RESUMO

The poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC)-modified, silicone hydrogel, contact lens (CL) material lehfilcon A has previously been demonstrated to have a lubricious, antifouling and ultra-soft surface. This study provides confirmatory identification of the outer polymer structures on this CL surface as branched PMPC structures. It further aims to understand their role in providing enhanced tribological performance via fluid confinement. A combination of scanning transmission electron microscopy and atomic force microscopy infrared spectroscopy has been used to achieve both morphological and chemical confirmation of branched PMPC structures resembling the polysaccharide species present on the surface of the cornea. Measurements of the fluid-confinement behaviour of this layer, by means of nanoindentation experiments, show it to resist squeeze-out of the interstitial fluid, thereby boosting lubrication by virtue of a fluid-load-support mechanism. Tribological testing of CLs showed this effective lubrication to be maintained after one month of daily wearing.

14.
Geburtshilfe Frauenheilkd ; 84(10): 920-927, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39359539

RESUMO

In many cases, outpatient surgical treatment of benign diseases of the uterus has advantages over inpatient care. This has been demonstrated by the healthcare situation in other countries. However, the prerequisite for the provision of outpatient services is that this does not lead to any impairment in the quality of care or of patient safety. The ultimate goal should not be to reduce costs but rather to maintain and, ideally, improve the quality of care. This requires that services are not just defined by the surgical procedure but also by the entire treatment chain, including, for example, psychosocial support, and are remunerated accordingly. It is particularly worrying that the final decision as to whether an outpatient operation is possible is not the responsibility of the operating unit, but of the "Medizinischer Dienst," with the corresponding options and threats of sanctions. This situation is unique internationally and requires a paradigm shift. Furthermore, structural prerequisites must be maintained which currently only exist inadequately in Germany. Since a substantial proportion of planned outpatient operations require immediate or secondary inpatient treatment, there must be a barrier-free transition between the outpatient and inpatient sectors. This will require the creation of networks between outpatient service providers and one or more hospitals that are equipped and competent to manage even complex complications. It is important to create structures that, with intensive involvement of the operating unit, include adequate preoperative evaluation and patient education as well as needs-oriented postoperative care at home. The current separation of sectors is a significant hinderance. Moreover, when expanding and promoting outpatient surgery, the aspect of training and further education of specialist staff must be taken into account, as well as cross-sectoral quality assurance. Based on a review of the international literature, this article presents 13 recommendations for adequate structures when providing outpatient services which should serve as a prerequisite for the greatest possible guarantee of patient safety.

15.
Nano Lett ; 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39365276

RESUMO

Atomically precise Pd-thiolate clusters are well-known for their well-defined structures and diverse applications involving catalysis, sensors, and biomedicine. While many of these clusters have been studied, their molecular structures typically feature a tiara-like arrangement. In this study, we present the first example of a non-tiara-like Pd-thiolate cluster: the octahedral Pd6(SC6H11)12 (denoted as Pd6-Oct). The composition and geometric structure of the cluster were characterized using electrospray ionization mass spectrometry (ESI-MS) together with single-crystal X-ray diffraction (SXRD). Despite having a similar chemical composition to tiara-like Pd6(SC2H4Ph)12 (denoted as Pd6-Tia), Pd6-Oct exhibits a distinctly different geometric structure. Additionally, UV-vis-NIR absorption spectroscopy combined with quantum chemical calculations provided valuable insights into the electronic structures of these clusters. The excited-state dynamics, host-guest chemistry, and the catalytic properties of Pd6-Oct and Pd6-Tia were examined to compare their structure-property relationships. This research represents significant advances in the synthesis and understanding of structure-property correlations in Pd-thiolate clusters.

16.
Comput Biol Med ; 183: 109227, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39369546

RESUMO

Large or carcinogenic bone defects may require a challenging bone tissue scaffold design ensuring a proper mechanobiological setting. Porosity and biodegradation rate are the key parameters controlling the bone-remodeling process. PLA presents a great potential for geometrically flexible 3-D scaffold design. This study aims to investigate the mechanical variation throughout the biodegradation process for lattice-type PLA scaffolds using both experimental observations and simulations. Three different unit-cell geometries are used for creating the scaffolds: basic cube (BC), body-centered structure (BCS), and body-centered cube (BCC). Three different porosity ratios, 50 %, 62.5 %, and 75 %, are assigned to all three structures by altering their strut dimensions. 3-D printed scaffolds are soaked in PBS solution at 37 °C for 15, 30, 60, 90, and 120 days both unloaded and under dead load. Water absorption, weight loss, and compression stiffness are measured to characterize the first-stage degradation and investigate the possible influences of these parameters on the whole biodegradation process. The strength reduction stage of biodegradation is simulated by solving pseudo-first-order kinetics-based molecular weight change equation using FEA with equisized cubic (voxel-like) elements. For the first stage, mechanical load does not have a statistically significant effect on biodegradation. BCC with 62.5 % porosity shows a maximum water absorption rate of around 25 % by the 60th day which brings an advantage in creating an aquatic environment for cell growth. Results indicate a significant water deposition inside almost all scaffolds and water content is determined to be the main reason for the retained or increased compression stiffness. A distinguishable stiffness increase in the initial degradation process occurs for 75 % porous BC and 50 % porous BCC scaffolds. Following the quasi-stable stage of biodegradation, almost all scaffolds lost their rigidity by around 44-48 % within 120 days based on numerical results. Therefore, initial stiffness increase in the quasi-stable stage of biodegradation can be advantageous and BCC geometry with a porosity between 50% and 62 % is the optimum solution for the whole biodegradation process.

17.
F S Sci ; 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39370108

RESUMO

OBJECTIVE: To determine whether tertiary lymphoid structures (TLSs), which reflect organized immune cell aggregates present in non-lymphoid tissues, are consistent features of endometriosis lesions. DESIGN: Detailed histopathological analysis of endometrial and lesion tissue from endometriosis patients and controls was performed. Multiplex immunofluorescence on select samples was then conducted to identify canonical cell populations present within TLSs: CD3+ and CD8+ T-cells, CD79a+ B-cells, CD208+ dendritic cells, CD21+ follicular dendritic cells (fDC), and PNAd+ high endothelial venules (HEVs). PATIENT(S): Histologically confirmed endometriosis patients (N=113; 44.3± 6.0) and control individuals (N=110; 44.6±7.1). INTERVENTION: Not applicable. MAIN OUTCOME MEASURE(S): Detection of TLSs as characterized by the presence of all canonical cell types that constitute TLS and structure morphology. RESULT(S): Of the selected samples (N=18; 6 ectopic/eutopic/control), mature TLSs were identified in 3 ectopic tissue samples present on the ovary and fallopian tube, with immature TLSs (lacking fDC networks and HEVs) present throughout eutopic and control endometrial samples. CONCLUSION: These findings demonstrate the presence of TLSs across various endometriosis phenotypes, prompting further research into their significance within disease pathophysiology and the prognostic implications for patients.

18.
Chem Asian J ; : e202400964, 2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-39414569

RESUMO

Reaction of lanthanoid tris(3,5-dimethylpyrazolate) compounds, [Ln(Me2pz)3(thf)]2 (Ln = La 1a, Ce, Pr, Dy 1b, Yb, Lu) with potassium or lithium bistrimethylsilylamide and with or without added 3,5-dimethylpyrazole, or of lanthanoid tris(bistrimethylsilyl)amide complexes with potassium bistrimethylsilylamide and 3,5-dimethylpyrazole have yielded a variety of oxide centred Ln3 or Ln4/(K or Li)1-3 multinuclear cages, namely, [La4O(Me2pz)11K(thf)2] (2a), [La4O(Me2pz)11Li(Me2pzH)]⋅0.5Hexane (2b), [La4O(Me2pz)10(Me2pzH)] (2c) (from heating 1a in toluene), [Ce3O(Me2pz)9K2(dme)2] (3a), [Ce3O(Me2pz)9Li2(thf)2]⋅0.5Hexane (3b) and [Ce(Me2pz)5Li2(thf)3] (3c), which crystallized together, [Ce3O(Me2pz)10K3(thf)3] (3d), [Pr3O(Me2pz)10K3(thf)3] (4), [Dy3O(Me2pz)9K2(thf)2]·THF (5), [Yb3O(Me2pz)9K2(thf)2]·THF (6), and [Lu3O(Me2pz)9K2(thf)2]⋅THF (7). Crystals of {[K8(Me2pz)8(thf)2]⋅THF}∞ (8) were also obtained from the preparation of 7. From reaction of [Ce(Me2pz)3(thf)]2 with potassium tert-butoxide in toluene, the cerium(IV) heterobimetallic polymer [Ce2(Me2pz)6(OtBu)4K2]∞ (9) was isolated. In the Ln3O and the Ln4O cages, the Ln atoms have triangular and distorted tetrahedral arrangements about the central oxygen, respectively. All metals are bound to the cages by a variety of pyrazolate binding modes, with up to five different exhibited in some structures, and a new coordination mode, µ4-1κ(N):2κ(N'):η5:η5, was observed in two complexes.

19.
J Appl Crystallogr ; 57(Pt 5): 1640-1649, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39387067

RESUMO

This article presents a web-based framework to build a database without in-depth programming knowledge given a set of CIF dictionaries and a collection of CIFs. The framework consists of two main elements: the public site that displays the information contained in the CIFs in an ordered manner, and the restricted administrative site which defines how that information is stored, processed and, eventually, displayed. Thus, the web application allows users to easily explore, filter and access the data, download the original CIFs, and visualize the structures via JSmol. The modulated structures open database B-IncStrDB, the official International Union of Crystallography repository for this type of material and available through the Bilbao Crystallographic Server, has been re-implemented following the proposed framework.

20.
J Appl Crystallogr ; 57(Pt 5): 1650-1666, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39387091

RESUMO

SUBGROUPS is a free online program at the Bilbao Crystallographic Server (https://www.cryst.ehu.es/). It permits the exploration of all possible symmetries resulting from the distortion of a higher-symmetry parent structure, provided that the relation between the lattices of the distorted and parent structures is known. The program calculates all the subgroups of the parent space group which comply with this relation. The required minimal input is the space-group information of the parent structure and the relation of the unit cell of the distorted or pseudo-symmetric structure with that of the parent structure. Alternatively, the wavevector(s) observed in the diffraction data characterizing the distortion can be introduced. Additional conditions can be added, including filters related to space-group representations. The program provides very detailed information on all the subgroups, including group-subgroup hierarchy graphs. If a Crystallographic Information Framework (CIF) file of the parent high-symmetry structure is uploaded, the program generates CIF files of the parent structure described under each of the chosen lower symmetries. These CIF files may then be used as starting points for the refinement of the distorted structure under these possible symmetries. They can also be used for density functional theory calculations or for any other type of analysis. The power and efficiency of the program are illustrated with a few examples.

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