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1.
BMC Pulm Med ; 24(1): 193, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649886

RESUMO

BACKGROUND: Granulomatosis with polyangiitis (GPA) is characterized by necrotizing granulomatous inflammation with necrotizing vasculitis predominantly affecting small to medium vessels. The survival rates have drastically improved; however, GPA can be lethal, with older patients having a worse prognosis and higher mortality than younger patients. Moreover, the incidence of various cancers has been reported to increase in patients with GPA. We aimed to discuss possible associations between GPA and lung cancer and emphasize the associated diagnostic challenges. CASE PRESENTATION: We encountered three older patients with chronic GPA who developed lung cancer during long-term follow-up. Two of the patients had a smoking history, with one having silicosis and the other having chronic obstructive pulmonary disease. Furthermore, all of them had radiation exposure from repeated radiography/computed tomography. All the patients had confirmed GPA, and vasculitis relapse was first suspected when new lung lesions were noted during follow-up. However, they had no new clinical symptoms, and serum ANCA titer increased only in one patient. All the patients received standard immunosuppressive treatment but eventually died. CONCLUSIONS: Lung cancer is uncommon in patients with GPA; however, the similarity between the imaging findings of lung cancer and GPA may pose a diagnostic challenge. Clinicians should be particularly vigilant when treating older patients with an increased risk of cancer, as they are often asymptomatic or have poorly apparent clinical features.


Assuntos
Granulomatose com Poliangiite , Neoplasias Pulmonares , Tomografia Computadorizada por Raios X , Humanos , Granulomatose com Poliangiite/complicações , Granulomatose com Poliangiite/diagnóstico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/complicações , Masculino , Idoso , Evolução Fatal , Feminino , Imunossupressores/uso terapêutico , Pessoa de Meia-Idade
2.
Inorg Chem ; 61(29): 11399-11409, 2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35797720

RESUMO

The interplay between a topological electronic structure and magnetism may result in intricate physics. In this work, we describe a case of rather peculiar coexistence or competition of several magnetic phases below seemingly single antiferromagnetic transition in LnSbTe (Ln = Ho and Tb) topological semimetals, the magnetic members of the ZrSiS/PbFCl structure type (space group P4/nmm). Neutron diffraction experiments reveal a complex multi-step order below TN = 3.8 K (Ln = Ho) and TN = 6.4 K (Ln = Tb). Magnetic phases can be described using four propagation vectors k1 = (1/2 0 0) and k2 = (1/2 0 1/4) at a base temperature of 1.7 K, which transform into incommensurate vectors k1' = (1/2 - δ 0 0) and k3 = (1/2 - δ 0 1/2) at elevated temperatures in both compounds. Together with the refined models of magnetic structures, we present the group theoretical analysis of magnetic symmetry of the proposed solutions. These results prompt further investigations of the relation between the electronic structure of those semimetals and the determined antiferromagnetic ordering existing therein.

3.
Chemistry ; 27(19): 5944-5955, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33319376

RESUMO

The mechanism for the mechanochemical synthesis of (C(NH2 )3 )3 PbI5 3 and (C(NH2 )3 )4 PbI6 4 and their conversion into each other is presented. We investigated the synthesis of 3 at different frequencies and energies using in situ powder X-ray diffraction. By splitting the reaction into single parts we could prove that the formation of 3 is simply dependent on the energy and mixing speed. The nucleation of 4 instead is slightly negative dependent on the energy but dependent on the mixing speed, while its growth is mostly independent of any influence. We were able to influence the reaction pathways by seeding the mixture with a small amount of powdery 4. The formation of 4 is very likely an auto-catalytic process. 3 instead is metastable. It can be stabilized by energy, which beside mechanochemistry can also be achieved by temperature. The results showcases the complex nature of mechanochemical reactions.

4.
Angew Chem Int Ed Engl ; 60(26): 14609-14619, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-33826206

RESUMO

The role of the perovskite lattice oxygen in the oxygen evolution reaction (OER) is systematically studied in the PrBaCo2 O5+δ family. The reduced number of physical/chemical variables combined with in-depth characterizations such as neutron dif-fraction, O K-edge X-ray absorption spectroscopy (XAS), electron energy loss spectroscopy (EELS), magnetization and scanning transmission electron microscopy (STEM) studies, helps investigating the complex correlation between OER activity and a single perovskite property, such as the oxygen content. Larger amount of oxygen vacancies appears to facilitate the OER, possibly contributing to the mechanism involving the oxidation of lattice oxygen, i.e., the lattice oxygen evolution reaction (LOER). Furthermore, not only the number of vacancies but also their local arrangement in the perovskite lattice influences the OER activity, with a clear drop for the more stable, ordered stoichiometry.

5.
Phys Rev Lett ; 124(1): 017202, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31976692

RESUMO

We report the discovery of topological magnetism in the candidate magnetic Weyl semimetal CeAlGe. Using neutron scattering we find this system to host several incommensurate, square-coordinated multi-k[over →] magnetic phases below T_{N}. The topological properties of a phase stable at intermediate magnetic fields parallel to the c axis are suggested by observation of a topological Hall effect. Our findings highlight CeAlGe as an exceptional system for exploiting the interplay between the nontrivial topologies of the magnetization in real space and Weyl nodes in momentum space.

6.
Clin Exp Rheumatol ; 36 Suppl 111(2): 40-45, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29745876

RESUMO

OBJECTIVES: Nasal carriage of Staphylococcus aureus and its superantigens (SAg) seem to be a risk factor disease exacerbation in granulomatosis with polyangiitis (GPA). We investigated the association between the presence of SAg in nasal swabs and activity of disease in GPA patients also taking into account correlation with an antimicrobial treatment. METHODS: In a prospective study of a total of 150 GPA patients hospitalised in the period 2009-2016, nasal swabs were examined for the presence of Staphylococcus aureus and SAg. Subsequently, the association with disease activity was assessed. RESULTS: Of 362 Staphylococcus aureus-positive nasal swab cultures from 115 of the 150 patients, the presence of at least one SAg in 126 samples (34.8%) from 56 patients (48.7%) was found. Among the 17 patients with limited to subglottic stenosis (SGS) disease, SAg were detected in 6 cases (35.3%). We did not find a significant correlation between the presence of SAg and disease activity (p=0.986), although when individual SAg were analysed separatively, SED and TSST-1 were more frequently present in active disease. Additionally, the results of the analysis demonstrated a protective effect of trimethoprim/sulfamethoxazole (T/S) treatment (0R 0.52, p<0.0092) in GPA patients. Interestingly, GPA limited to SGS appeared as an unfavourable factor associated with disease activity (0R 1.84, p=0.05). CONCLUSIONS: The association between staphylococcal SAg in nasal swabs and GPA activity is not evident. Multiple mechanisms that may lead to disease activation still need to be investigated.


Assuntos
Antígenos de Bactérias/imunologia , Portador Sadio/imunologia , Granulomatose com Poliangiite/imunologia , Mucosa Nasal/imunologia , Infecções Estafilocócicas/imunologia , Staphylococcus aureus/imunologia , Superantígenos/imunologia , Adulto , Portador Sadio/microbiologia , Feminino , Granulomatose com Poliangiite/microbiologia , Granulomatose com Poliangiite/fisiopatologia , Humanos , Laringoestenose/imunologia , Laringoestenose/microbiologia , Laringoestenose/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Infecções Estafilocócicas/microbiologia , Staphylococcus/imunologia , Staphylococcus aureus/isolamento & purificação
7.
Rev Sci Instrum ; 95(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38953722

RESUMO

The elastic moduli provide unique insights into the thermodynamics of quantum materials, particularly into the symmetries broken at their phase transition. Here, we present a workflow to carve crystalline resonators via focused ion beam milling from small and oddly shaped crystals unsuitable for traditional measurements of elasticity. The accuracy of this technique is first established in silicon. Next, we showcase the capacity to probe changes in the electronic state with a resolution on the measured resonance frequency as small as 0.01% on YNiO3, a rare-earth perovskite nickelate, in which bulk single crystals have typical length scales of ≈40µm. Here, we observe a sharp 0.2% discontinuity in Young's modulus of an YNiO3 cantilever at a magnetic phase transition. Finally, an additional potential of using free-standing cantilevers as a tool for examining the time-dependence of chemical changes is illustrated by laser-heating YNiO3.

8.
Nat Commun ; 15(1): 1658, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38395887

RESUMO

Charge density wave (CDW) orders in vanadium-based kagome metals have recently received tremendous attention, yet their origin remains a topic of debate. The discovery of ScV6Sn6, a bilayer kagome metal featuring an intriguing [Formula: see text] CDW order, offers a novel platform to explore the underlying mechanism behind the unconventional CDW. Here, we combine high-resolution angle-resolved photoemission spectroscopy, Raman scattering and density functional theory to investigate the electronic structure and phonon modes of ScV6Sn6. We identify topologically nontrivial surface states and multiple van Hove singularities (VHSs) in the vicinity of the Fermi level, with one VHS aligning with the in-plane component of the CDW vector near the [Formula: see text] point. Additionally, Raman measurements indicate a strong electron-phonon coupling, as evidenced by a two-phonon mode and new emergent modes. Our findings highlight the fundamental role of lattice degrees of freedom in promoting the CDW in ScV6Sn6.

9.
Pneumonol Alergol Pol ; 81(4): 319-22, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23744167

RESUMO

INTRODUCTION: Inherited alpha-1 antitrypsin (AAT) deficiency is one of the three most common genetic disorders in Caucasians. It considerably increases the risk of progressive obstructive lung diseases, mostly chronic obstructive pulmonary disease. It has also been suggested that AAT deficiency might be instrumental vasculitis associated with the anti-neutrophil cytoplasm antibodies (cANCA) and subsequent lung tissue injury. MATERIAL AND METHODS: We present the results from a pilot study involving 51 patients with granulomatosis with polyangiitis, formerly known as Wegener's granulomatosis (GPA), 43 of whom were cANCA positive. The control group consisted of 658 individuals. AAT blood concentration assessment by nephelometry, phenotyping by isoelectrofocusing and real-time PCR genotyping were performed. RESULTS: Deficiency alleles PI*Z and PI*S were detected in 3 (5.88%) and in 2 patients (3.92%) with GPA, respectively. All of them were cANCA positive. In the controls, PI*Z was observed in 2.8% while PI*S in 1.5% of cases. Accordingly, the increased incidence of main deficiency alleles was demonstrated in GPA, and particularly in cANCA+GPA patients, when compared to the controls. The estimated frequency for PI*Z in GPA, cANCA+GPA patients and controls was, respectively, 29.4/1000, 34.9/1000 and 13.7/1000, whereas for PI*S it was 19.2/1000, 23.2/10,00 and 7.6/1000. However, the observed differences did not reach statistical significance due to the considerable size disproportion between groups. CONSCLUSIONS: We believe that our preliminary data confirm the clinical importance of AAT deficiency in GPA patients and the need to screen for AAT deficiency alleles. The study is on-going.


Assuntos
Granulomatose com Poliangiite/genética , Deficiência de alfa 1-Antitripsina/genética , alfa 1-Antitripsina/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Estudos de Casos e Controles , Feminino , Frequência do Gene , Granulomatose com Poliangiite/sangue , Granulomatose com Poliangiite/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Polônia/epidemiologia , Prevalência , Adulto Jovem , alfa 1-Antitripsina/sangue , Deficiência de alfa 1-Antitripsina/sangue , Deficiência de alfa 1-Antitripsina/epidemiologia
10.
Pneumonol Alergol Pol ; 81(4): 404-10, 2013.
Artigo em Polonês | MEDLINE | ID: mdl-23744172

RESUMO

The antiphospholipid syndrome is characterized by the presence of antiphospholipid antibodies and the association of protean clinical manifestations as a result of both venous and arterial thrombosis. While pulmonary embolism (secondary to deep vein thrombosis) is common and well-known disturbance in antiphospholipid syndrome, recently there are growing number of case reports describing nonthrombotic lung pathologies in APS. We present here a young male with antiphospholipid syndrome, whose the only manifestation was diffuse alveolar hemorrhage.


Assuntos
Síndrome Antifosfolipídica/diagnóstico , Hemorragia/diagnóstico , Pneumopatias/diagnóstico , Alvéolos Pulmonares/patologia , Adulto , Hemorragia/etiologia , Hemorragia/patologia , Humanos , Pneumopatias/etiologia , Pneumopatias/patologia , Masculino , Tomografia Computadorizada por Raios X
11.
Materials (Basel) ; 16(8)2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37109886

RESUMO

The objective of this work is to review and assess the potential of MgB4O7:Ce,Li to fill in the gaps where the need for a new material for optically stimulated luminescence (OSL) dosimetry has been identified. We offer a critical assessment of the operational properties of MgB4O7:Ce,Li for OSL dosimetry, as reviewed in the literature and complemented by measurements of thermoluminescence spectroscopy, sensitivity, thermal stability, lifetime of the luminescence emission, dose response at high doses (>1000 Gy), fading and bleachability. Overall, compared with Al2O3:C, for example, MgB4O7:Ce,Li shows a comparable OSL signal intensity following exposure to ionizing radiation, a higher saturation limit (ca 7000 Gy) and a shorter luminescence lifetime (31.5 ns). MgB4O7:Ce,Li is, however, not yet an optimum material for OSL dosimetry, as it exhibits anomalous fading and shallow traps. Further optimization is therefore needed, and possible avenues of investigation encompass gaining a better understanding of the roles of the synthesis route and dopants and of the nature of defects.

12.
Nat Commun ; 14(1): 8050, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38052859

RESUMO

Magnetic skyrmions, topological vortex-like spin textures, garner significant interest due to their unique properties and potential applications in nanotechnology. While they typically form a hexagonal crystal with distinct internal magnetisation textures known as Bloch- or Néel-type, recent theories suggest the possibility for direct transitions between skyrmion crystals of different lattice structures and internal textures. To date however, experimental evidence for these potentially useful phenomena have remained scarce. Here, we discover the polar tetragonal magnet EuNiGe3 to host two hybrid skyrmion phases, each with distinct internal textures characterised by anisotropic combinations of Bloch- and Néel-type windings. Variation of the magnetic field drives a direct transition between the two phases, with the modification of the hybrid texture concomitant with a hexagonal-to-square skyrmion crystal transformation. We explain these observations with a theory that includes the key ingredients of momentum-resolved Ruderman-Kittel-Kasuya-Yosida and Dzyaloshinskii-Moriya interactions that compete at the observed low symmetry magnetic skyrmion crystal wavevectors. Our findings underscore the potential of polar magnets with rich interaction schemes as promising for discovering new topological magnetic phases.

13.
Commun Phys ; 6(1): 223, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38665398

RESUMO

The microscopic mechanism of heavy band formation, relevant for unconventional superconductivity in CeCoIn5 and other Ce-based heavy fermion materials, depends strongly on the efficiency with which f electrons are delocalized from the rare earth sites and participate in a Kondo lattice. Replacing Ce3+ (4f1, J = 5/2) with Sm3+ (4f5, J = 5/2), we show that a combination of the crystal electric field and on-site Coulomb repulsion causes SmCoIn5 to exhibit a Γ7 ground state similar to CeCoIn5 with multiple f electrons. We show that with this single-ion ground state, SmCoIn5 exhibits a temperature-induced valence crossover consistent with a Kondo scenario, leading to increased delocalization of f holes below a temperature scale set by the crystal field, Tv ≈ 60 K. Our result provides evidence that in the case of many f electrons, the crystal field remains the dominant tuning knob in controlling the efficiency of delocalization near a heavy fermion quantum critical point, and additionally clarifies that charge fluctuations play a general role in the ground state of "115" materials.

14.
Pneumonol Alergol Pol ; 80(1): 20-8, 2012.
Artigo em Polonês | MEDLINE | ID: mdl-22187177

RESUMO

INTRODUCTION: The diagnosis of Churg-Strauss syndrome (CSS) is difficult because pathological criteria are present in minority of patients and in advanced stages. Several centers elaborated criteria which allowed to suspect CSS in patients with asthma, hypereosinophilia and clinical manifestations consistent with systemic vasculitis with or without histologic evidence. The aim of the study is the presentation of the basis of CSS diagnosis in our material. MATERIAL AND METHODS: The analysis included 38 patients. Blood and biochemical analysis, radiological examinations of the chest and sinuses, echocardiography were performed in all patients. In 22/23 patients with cardiac symptoms magnetic resonance of the heart was performed. In two patients mediastinoscopy was performed, in 4--laparotomy. RESULTS: Only in 13/38 patients vasculitis was histologically proven, in the rest the diagnosis was established mainly on clinical ground. In 23 patients the diagnosis was established on the clinical cardiac symptoms--in all of them the cardiac involvement was confirmed by magnetic resonance. In 9 cases skin leasions were cause of further diagnostic procedures, 6 patients presented gastrointestinal symptoms, in 15--paralysis of peroneal nerve was observed, and 1 patient had polyneuropathy and symptoms of central nervous system. CONCLUSIONS: The diagnosis of CSS in our material was established mainly on clinical ground, because histologic material was difficult to obtain (it needs invasive procedures). Only in 13 from 38 patients vasculitis was histologically proven. The presence of asthma, sinusitis associated with peripheral eosinophilia and organ symptoms suggesting a vasculitis could support the diagnosis, without histologic evidence.


Assuntos
Síndrome de Churg-Strauss/diagnóstico , Vasculite/diagnóstico , Adolescente , Adulto , Asma/complicações , Síndrome de Churg-Strauss/complicações , Diagnóstico Diferencial , Ecocardiografia , Eletrocardiografia Ambulatorial , Eosinofilia/etiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Prognóstico , Radiografia Torácica , Estudos Retrospectivos , Sinusite/complicações , Vasculite/complicações , Vasculite/patologia , Adulto Jovem
15.
Diagnostics (Basel) ; 12(8)2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-36010230

RESUMO

Granulomatosis with polyangiitis (GPA) is a rare systemic vasculitis that classically affects the upper respiratory tract, lungs, and kidneys. The involvement of other organs occurs but is less frequent. Clinically overt cardiac involvement is rare. We present a rare case of thoracic pain caused by cardiac involvement in GPA, without any other symptoms. The diagnosis was made using an integral approach, with several complementary imaging modalities, including cardiac histology.

16.
Sci Adv ; 8(43): eabq6589, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36306356

RESUMO

Crystalline symmetry is a defining factor of the electronic band topology in solids, where many-body interactions often induce a spontaneous breaking of symmetry. Superconductors lacking an inversion center are among the best systems to study such effects or even to achieve topological superconductivity. Here, we demonstrate that TRuSi materials (with T a transition metal) belong to this class. Their bulk normal states behave as three-dimensional Kramers nodal-line semimetals, characterized by large antisymmetric spin-orbit couplings and by hourglass-like dispersions. Our muon-spin spectroscopy measurements show that certain TRuSi compounds spontaneously break the time-reversal symmetry at the superconducting transition, while unexpectedly showing a fully gapped superconductivity. Their unconventional behavior is consistent with a unitary (s + ip) pairing, reflecting a mixture of spin singlets and spin triplets. By combining an intrinsic time-reversal symmetry-breaking superconductivity with nontrivial electronic bands, TRuSi compounds provide an ideal platform for investigating the rich interplay between unconventional superconductivity and the exotic properties of Kramers nodal-line/hourglass fermions.

17.
Pneumonol Alergol Pol ; 79(2): 127-31, 2011.
Artigo em Polonês | MEDLINE | ID: mdl-21351064

RESUMO

We present a case of 26 years old man with large spontaneous pneumothorax of about 5 days duration. Application of suction drainage was complicated by unilateral reexpansion pulmonary edema (REPE) and hemothorax developed during first 24 hours of treatment. On thoracotomy multifocal superficial pleural bleeding was seen which was probably attributed to the pathomechanisms similar to suggested in reexpansion pulmonary edema. The patient received supplemental oxygen therapy and completely recovered during next few days. The patient presented typical risk factors of REPE including: young age, large and prolonged pneumothorax. In such cases chest tube should be initially left off suction to prevent REPE.


Assuntos
Hemotórax/etiologia , Edema Pulmonar/etiologia , Sucção/efeitos adversos , Adulto , Humanos , Masculino , Pneumotórax/terapia , Resultado do Tratamento
18.
Materials (Basel) ; 14(24)2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34947489

RESUMO

Properties of FeTe0.65Se0.35 single crystals, with the onset of critical temperature (Tconset) at 15.5 K, were modified via hydrogenation performed for 10-90 h, at temperatures ranging from 20 to 250 °C. It was found that the tetragonal matrix became unstable and crystal symmetry lowered for the samples hydrogenated already at 200 °C. However, matrix symmetry was not changed and the crystal was not destroyed after hydrogenation at 250 °C. Bulk Tcbulk, determined at the middle of the superconducting transition, which is equal to 12-13 K for the as grown FeTe0.65Se0.35, rose by more than 1 K after hydrogenation. The critical current density studied in magnetic field up to 70 kOe increased 4-30 times as a consequence of hydrogenation at 200 °C for 10 h. Electron paramagnetic resonance measurements also showed higher values of Tcbulk for hydrogenated crystals. Thermal diffusion of hydrogen into the crystals causes significant structural changes, leads to degeneration of crystal quality, and significantly alters superconducting properties. After hydrogenation, a strong correlation was noticed between the structural changes and changes in the parameters characterizing the superconducting state.

19.
Pneumonol Alergol Pol ; 78(1): 79-82, 2010.
Artigo em Polonês | MEDLINE | ID: mdl-20162523

RESUMO

Three patients with pleural sarcoidosis are reported. Pleural effusion in two patients and a massive pleural thickening that mimicked a tumour were observed. Histological examination of pleural biopsies revealed sarcoidosis. None of the patients received treatment. No recurrence of the pleural effusion was observed after a year of follow-up and the massive pleural thickening remained stable.


Assuntos
Derrame Pleural/diagnóstico , Derrame Pleural/patologia , Sarcoidose/diagnóstico , Sarcoidose/patologia , Adulto , Idoso , Feminino , Humanos , Pulmão/patologia , Masculino , Pessoa de Meia-Idade
20.
Polymers (Basel) ; 12(2)2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32033051

RESUMO

Five coordination polymers formed from combinations of copper(II) acetate and 4'-(4-alkyloxyphenyl)-3,2':6',3''-terpyridines with methoxy (1), n-butoxy (2), n-pentyloxy (3) and n-heptyloxy (4) substituents are reported. Reaction of 1 with Cu(OAc)2∙H2O leads to the 1D-polymer [Cu2(µ-OAc)4(1)]n in which {Cu2(-OAc)4} paddle-wheel units are connected by ligands 1, or [{Cu4(µ3-OH)2(µ-OAc)2(µ3-OAc)2(AcO-κO)2(1)2}.2MeOH]n in which centrosymmetric tetranuclear clusters link pairs of ligands 1 to give a double-stranded 1D-polymer. Layering solutions of Cu(OAc)2∙H2O (in MeOH) over 2, 3 or 4 (in CHCl3) leads to the assembly of the 1D-polymers [2{Cu2(µ-OAc)4(2)}.1.25MeOH]n, [Cu2(µ-OAc)4(3)]n and [{Cu2(µ-OAc)4(4)}.0.2CHCl3]n. In all compounds, the 3,2':6',3''-tpy unit coordinates only through the outer pyridine rings, but the conformation of the 3,2':6',3''-tpy responds to changes in the length of the alkyloxy tails leading to changes in the conformation of the polymer backbone and in the packing of the chains in the crystal lattice in the chains featuring {Cu2(-OAc)4} paddle-wheel linkers.

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