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1.
Eur Radiol ; 33(6): 4228-4236, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36905469

RESUMO

OBJECTIVES: To provide insights for on-site development of transformer-based structuring of free-text report databases by investigating different labeling and pre-training strategies. METHODS: A total of 93,368 German chest X-ray reports from 20,912 intensive care unit (ICU) patients were included. Two labeling strategies were investigated to tag six findings of the attending radiologist. First, a system based on human-defined rules was applied for annotation of all reports (termed "silver labels"). Second, 18,000 reports were manually annotated in 197 h (termed "gold labels") of which 10% were used for testing. An on-site pre-trained model (Tmlm) using masked-language modeling (MLM) was compared to a public, medically pre-trained model (Tmed). Both models were fine-tuned on silver labels only, gold labels only, and first with silver and then gold labels (hybrid training) for text classification, using varying numbers (N: 500, 1000, 2000, 3500, 7000, 14,580) of gold labels. Macro-averaged F1-scores (MAF1) in percent were calculated with 95% confidence intervals (CI). RESULTS: Tmlm,gold (95.5 [94.5-96.3]) showed significantly higher MAF1 than Tmed,silver (75.0 [73.4-76.5]) and Tmlm,silver (75.2 [73.6-76.7]), but not significantly higher MAF1 than Tmed,gold (94.7 [93.6-95.6]), Tmed,hybrid (94.9 [93.9-95.8]), and Tmlm,hybrid (95.2 [94.3-96.0]). When using 7000 or less gold-labeled reports, Tmlm,gold (N: 7000, 94.7 [93.5-95.7]) showed significantly higher MAF1 than Tmed,gold (N: 7000, 91.5 [90.0-92.8]). With at least 2000 gold-labeled reports, utilizing silver labels did not lead to significant improvement of Tmlm,hybrid (N: 2000, 91.8 [90.4-93.2]) over Tmlm,gold (N: 2000, 91.4 [89.9-92.8]). CONCLUSIONS: Custom pre-training of transformers and fine-tuning on manual annotations promises to be an efficient strategy to unlock report databases for data-driven medicine. KEY POINTS: • On-site development of natural language processing methods that retrospectively unlock free-text databases of radiology clinics for data-driven medicine is of great interest. • For clinics seeking to develop methods on-site for retrospective structuring of a report database of a certain department, it remains unclear which of previously proposed strategies for labeling reports and pre-training models is the most appropriate in context of, e.g., available annotator time. • Using a custom pre-trained transformer model, along with a little annotation effort, promises to be an efficient way to retrospectively structure radiological databases, even if not millions of reports are available for pre-training.


Assuntos
Radiologia , Humanos , Bases de Dados Factuais , Processamento de Linguagem Natural , Radiologia/métodos , Estudos Retrospectivos , Cor
2.
Phys Rev Lett ; 122(15): 155003, 2019 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-31050499

RESUMO

The excitation mechanism for low-n edge harmonic oscillations in quiescent H-mode regimes is identified analytically. We show that the combined effect of diamagnetic and poloidal magnetohydrodynamic flows, with the constraint of a Doppler-like effect of the ion flow, leads to the stabilization of short wavelength modes, allowing low-n perturbation to grow. The analysis, performed in tokamak toroidal geometry, includes the effects of large edge pressure gradients, associated with the local flattening of the safety factor and diamagnetic flows, sheared parallel and E×B rotation, and a vacuum region between plasma and the ideal metallic wall. The separatrix also is modeled analytically.

3.
BMC Cardiovasc Disord ; 18(1): 146, 2018 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-30005637

RESUMO

BACKGROUND: It has been suggested that changes in pulmonary veins (PV) and left atrium (LA) anatomy may have an influence on initiating atrial fibrillation (AF) and the effectiveness of pulmonary vein isolation (PVI) in patients (pts) with atrial fibrillation. The aim of the study was to assess anatomy abnormalities of the PV and LA in the patients with the history of AF and compare it with the control group(CG). METHODS: The multi-slice tomography (MSCT) scans were performed in 224 AF pts. before PVI (129 males, mean age 59 ± 9 yrs). The CG consisted of 40 pts. without AF (26 males, age 45 ± 9 yrs). LA and PV anatomy were evaluated. Diameters of PV ostia were measured in two directions: anterior-posterior (AP) and superior-inferior (SI) automatically using Vitrea 4.0. RESULTS: Pulmonary veins anatomy variants were observed more frequently in the atrial fibrillation group - 83 pts. (37%) vs 6 pts. (15%) in CG; 9% (21 pts) left common ostia (CO), 2% (5 pts) right CO, 19% (42 pts) additional right PV (APV), (1.8%) 4 pts. APV left, 8% right early branching (EB) and 3.5% left EB. The LA diameter differed significantly in AF vs CG group (41.2 ± 6 mm vs 35 ± 4.2 mm, p < 0.0001) respectively. CONCLUSIONS: The anomalies of pulmonary vein anatomy occurred more often in pts. with AF. They can be defined as an image biomarkers of atrial fibrillation. Right additional (middle) pulmonary vein was the most important anomaly detected in AF patients as well as enlargered diameters of the LA and PV ostia.


Assuntos
Fibrilação Atrial/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Tomografia Computadorizada Multidetectores/métodos , Flebografia/métodos , Veias Pulmonares/anormalidades , Veias Pulmonares/diagnóstico por imagem , Adulto , Idoso , Fibrilação Atrial/etiologia , Fibrilação Atrial/cirurgia , Estudos de Casos e Controles , Feminino , Átrios do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Veias Pulmonares/cirurgia , Fatores de Risco , Adulto Jovem
4.
Phys Chem Chem Phys ; 18(38): 26595-26601, 2016 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-27711648

RESUMO

The changes in electrolyte composition on the molecular level and the reaction mechanisms of electrolyte degradation upon thermal aging are monitored by quantitative NMR spectroscopy, revealing similar rates of degradation for pristine and already aged electrolytes. The data analysis is not in favor of an autocatalytic reaction mechanism based on OPF3 but rather indicates that the degradation of LiPF6 in carbonate based solvents proceeds via a complex sequence of "linear" reactions rather than a cyclic reaction pattern which is determined by the amount of water present in the samples. All investigated electrolytes are reasonably stable at temperatures of up to 60 °C in the presence of minor amounts or absence of water hence indicating that chemical instability of electrolyte components against water is decisive for degradation and an increase in temperature ("thermal aging") just accelerates the degradation impact of water.

5.
Phys Chem Chem Phys ; 18(5): 3956-65, 2016 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-26771035

RESUMO

The 1st cycle Coulombic efficiency (CE) of LiNi1/3Co1/3Mn1/3O2 (NCM) at 4.6 V vs. Li/Li(+) has been extensively investigated in NCM/Li half cells. It could be proven that the major part of the observed overall specific capacity loss (in total 36.3 mA h g(-1)) is reversible and induced by kinetic limitations, namely an impeded lithiation reaction during discharge. A measure facilitating the lithiation reaction, i.e. a constant potential (CP) step at the discharge cut-off potential, results in an increase in specific discharge capacity of 22.1 mA h g(-1). This capacity increase during the CP step could be proven as a relithiation process by Li(+) content determination in NCM via an ICP-OES measurement. In addition, a specific capacity loss of approx. 4.2 mA h g(-1) could be determined as an intrinsic reaction to the NCM cathode material at room temperature (RT). In total, less than 10.0 mA h g(-1) (=28% of the overall capacity loss) can be attributed to irreversible reactions, mainly to irreversible structural changes of NCM. Thus, the impact of parasitic reactions, such as oxidative electrolyte decomposition, on the irreversible capacity is negligible and could also be proven by on-line MS. As a consequence, the determination of the amount of extracted Li(+) ("Li(+) extraction ratio") so far has been incorrect and must be calculated by the charge capacity (=delithiation amount) divided by the theoretical capacity. In a NCM/graphite full cell the relithiation amount during the constant voltage (CV) step is smaller than in the half cell, due to irreversible Li(+) loss at graphite.

6.
Child Care Health Dev ; 42(5): 683-91, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27273161

RESUMO

BACKGROUND: The introduction of the International Classification of Functioning, Disabilities and Health of the World Health Organization in 2001 made social participation a major rehabilitation outcome and the ultimate goal of rehabilitation services. There is no available instrument to measure the youth participation in leisure activities apart from asking the youth themselves. The goal of this study was to present a German version of the Children's Assessment of Participation and Enjoyment and Preferences for Activities of Children (CAPE/PAC). METHODS: The CAPE/PAC questionnaire was translated into German, a cultural adaptation process was designed and a reliability study was conducted. One hundred and fifty-two youths with and without disabilities, with a mean age of 15.2 years (standard deviation 1.7), participated in the study. The participants completed CAPE and PAC twice within 4 weeks. Reliability was examined by intraclass correlation coefficients, standard error of measurement, smallest detectable change and Cronbach's alpha. RESULTS: The absolute values of participation differ between the typically developed youth group and those with impairments; the reliability of the CAPE/PAC is comparable in both groups. Intraclass correlation coefficients ranged from 0.43 to 0.74 for the CAPE and from 0.71 to 0.83 for the PAC in all participants. The alpha values for internal consistency ranged from 0.42 to 0.82 for the CAPE and from 0.65 to 0.92 for the PAC. CONCLUSIONS: The German version of the PAC showed satisfactory reliability; however, reliability was not satisfactory for all scores of the CAPE, but comparable with versions in other languages. The need for newly developed participation measurements requires further discussion.


Assuntos
Relações Interpessoais , Atividades de Lazer/psicologia , Participação Social , Adolescente , Criança , Doença Crônica , Crianças com Deficiência/psicologia , Feminino , Grupos Focais , Alemanha , Humanos , Masculino , Reprodutibilidade dos Testes , Inquéritos e Questionários , Tradução
8.
J Phys Condens Matter ; 34(50)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36261038

RESUMO

X-ray resonant Raman spectroscopy (XRRS), a variant of resonant inelastic x-ray scattering, has been used to investigate the two prototype systems, UF4and UO2. Both are U5f2and each is an example of 5f localized, ionic behavior and 5f localized, covalent behavior, respectively. From the M5XRRS measurements, the 5f band gap in each can be directly determined and, moreover, a clear and powerful sensitivity to 5f covalency emerges.

9.
Phys Rev Lett ; 107(5): 053001, 2011 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-21867065

RESUMO

Experimental evidence for the correlated two-electron one-photon transitions (1s(-2)→2s(-1)2p(-1)) following single-photon K-shell double ionization is reported. The double K-shell vacancy states in solid Mg, Al, and Si were produced by means of monochromatized synchrotron radiation, and the two-electron one-photon radiative transitions were observed by using a wavelength dispersive spectrometer. The two-electron one-photon transition energies and the branching ratios of the radiative one-electron to two-electron transitions were determined and compared to available perturbation theory predictions and configuration interaction calculations.

10.
J Phys Condens Matter ; 33(49)2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34507312

RESUMO

Time resolved pump and probe acoustics and first-principles calculations were employed to assess elastic properties of the TbMnO3perovskite manganite having orthorhombic symmetry. Measuring sound velocities of bulk longitudinal and shear acoustic waves propagating along at least two different directions in the high symmetry planes (100), (010) and (001), provided a powerful mean to selectively determine the six diagonal elastic constantsC11= 227 GPa,C22= 349 GPa,C33= 274 GPa,C44= 71 GPa,C55= 57 GPa,C66= 62 GPa. Among the three remaining off-diagonal ones,C23= 103 GPa was determined with a bissectrice direction. Density functional theory calculations with colinear spin-polarized provided complementary insights on their optical, elastic and magnetoelastic properties.

11.
J Dent Res ; 100(11): 1220-1227, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34077690

RESUMO

Dental care professionals (DCPs) are thought to be at enhanced risk of occupational exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, robust data to support this from large-scale seroepidemiological studies are lacking. We report a longitudinal seroprevalence analysis of antibodies to SARS-CoV-2 spike glycoprotein, with baseline sampling prior to large-scale practice reopening in July 2020 and follow-up postimplementation of new public health guidance on infection prevention control (IPC) and enhanced personal protective equipment (PPE). In total, 1,507 West Midlands DCPs were recruited into this study in June 2020. Baseline seroprevalence was determined using a combined IgGAM enzyme-linked immunosorbent assay and the cohort followed longitudinally for 6 mo until January/February 2021 through the second wave of the coronavirus disease 2019 pandemic in the United Kingdom and vaccination commencement. Baseline seroprevalence was 16.3%, compared to estimates in the regional population of 6% to 7%. Seropositivity was retained in over 70% of participants at 3- and 6-mo follow-up and conferred a 75% reduced risk of infection. Nonwhite ethnicity and living in areas of greater deprivation were associated with increased baseline seroprevalence. During follow-up, no polymerase chain reaction-proven infections occurred in individuals with a baseline anti-SARS-CoV-2 IgG level greater than 147.6 IU/ml with respect to the World Health Organization international standard 20-136. After vaccination, antibody responses were more rapid and of higher magnitude in those individuals who were seropositive at baseline. Natural infection with SARS-CoV-2 prior to enhanced PPE was significantly higher in DCPs than the regional population. Natural infection leads to a serological response that remains detectable in over 70% of individuals 6 mo after initial sampling and 9 mo from the peak of the first wave of the pandemic. This response is associated with protection from future infection. Even if serological responses wane, a single dose of the Pfizer-BioNTech 162b vaccine is associated with an antibody response indicative of immunological memory.


Assuntos
COVID-19 , Vacinas , Assistência Odontológica , Humanos , SARS-CoV-2 , Estudos Soroepidemiológicos , Reino Unido/epidemiologia
12.
Rev Sci Instrum ; 91(3): 033101, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32259983

RESUMO

We present a high energy resolution x-ray spectrometer for the tender x-ray regime (1.6-5.0 keV) that was designed and operated at Stanford Synchrotron Radiation Lightsource. The instrument is developed on a Rowland geometry (500 mm of radius) using cylindrically bent Johansson analyzers and a position sensitive detector. By placing the sample inside the Rowland circle, the spectrometer operates in an energy-dispersive mode with a subnatural line-width energy resolution (∼0.32 eV at 2400 eV), even when an extended incident x-ray beam is used across a wide range of diffraction angles (∼30° to 65°). The spectrometer is enclosed in a vacuum chamber, and a sample chamber with independent ambient conditions is introduced to enable a versatile and fast-access sample environment (e.g., solid/gas/liquid samples, in situ cells, and radioactive materials). The design, capabilities, and performance are presented and discussed.

13.
Science ; 292(5516): 461-4, 2001 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-11264526

RESUMO

We report the realization of a Bose-Einstein condensate of metastable atoms (helium in the lowest triplet state). The excitation energy of each atom with respect to the ground state is 20 electron volts, but inelastic processes that would destroy the sample are suppressed strongly enough in a spin-polarized sample to allow condensation. Our detection scheme takes advantage of the metastability to achieve detection of individual atoms as well as of the decay products of inelastic processes. This detection opens the way toward new studies in mesoscopic quantum statistical physics, as well as in atomic quantum optics.

14.
Stud Health Technol Inform ; 138: 34-48, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18560106

RESUMO

The paper describes a platform developed for the secure management and analysis of medical data and images in a grid environment. Designed for telemedicine and built upon the EGEE gLite middleware and particularly the metadata catalogue AMGA as well as the GridSphere web portal, the platform provides to healthcare professionals the capacity to upload and query medical information stored over distributed servers. A job submission environment is also available for data analysis. Security features include authentication and authorization by grid certificates, anonymization of medical data and image encryption. The platform is currently deployed on several sites in Europe and Asia and is being customized for applications in the field of telemedicine and medical physics.


Assuntos
Segurança Computacional/instrumentação , Sistemas Computacionais , Computação em Informática Médica , Sistemas Computadorizados de Registros Médicos/organização & administração , Telemedicina/organização & administração , Acesso à Informação , Algoritmos , Bases de Dados como Assunto , França , Humanos , Método de Monte Carlo , Neurocirurgia/organização & administração , Software
15.
Clin Neurol Neurosurg ; 173: 154-158, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30142621

RESUMO

OBJECTIVES: Hydrocephalus can be defined as clinically symptomatic dilatation of the internal ventricular system at the expense of brain and blood volume. Shunt insertion is the mainstay of therapy for communicating hydrocephalus. One of the most frequently used valves is the programmable Codman Medos Hakim valve which enables the pressure level to be adjusted from 30 to 200 mmH2O. The problem of functional over- or underdrainage and the associated complications should be significantly reduced if not excluded. Especially in the clinical application of the Codman Medos Hakim Shunt System in hydrocephalus of other etiology only a few studies can be found. This study aims to increase knowledge of both the safety of Codman Medos valves with SiphonGuard in the clinical application as well as the correct choice of the pressure level for different indications. PATIENTS AND METHODS: In this retrospective study, 101 patients were included who underwent surgery with the adjustable "Codman Medos Hakim" valve with "SiphonGuard" between January 2010 and July 2013. We analyzed the patient files and imaging (CCT, cMRT) data. The statistical examinations were performed using the WINStat program for Excel. RESULTS: Our results show that an initial pressure level of 120mmH2O proved to be suitable in all subgroups. After optimization of the initial pressure level 70.3% of the valves (71 valves) had a pressure level of 120mmH2O. Importantly, only in the SAH subgroup the clinical improvement was correlated with a reduction in the measured indices. But in all subgroups a clinical deterioration was associated with an increased ventricular size. CONCLUSION: Overall, the clinical data show that an initial pressure level of 120mmH2O seems to be appropriate for most patients treated in this series. Measured indices from the cranial imaging can provide valuable indications for the presence of a suboptimal valve setting for the individual patient.


Assuntos
Derivações do Líquido Cefalorraquidiano , Hidrocefalia/cirurgia , Complicações Pós-Operatórias/etiologia , Próteses e Implantes , Adolescente , Adulto , Pressão do Líquido Cefalorraquidiano/fisiologia , Derivações do Líquido Cefalorraquidiano/instrumentação , Criança , Pré-Escolar , Desenho de Equipamento , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Adulto Jovem
16.
RSC Adv ; 8(21): 11785-11798, 2018 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35558550

RESUMO

ZnO-ZnS 1D hetero-nanostructures were prepared by an easy and scalable processing route. It consists of ZnO nanorod electrodeposition on ITO substrate and surface sulfidation by ion exchange in an aqueous Na2S solution. Increasing the treatment contact time (t c) from 8 to 48 h involves different ZnS growth mechanisms leading to different structural and microstructural rod characteristics, even if the overall size does not change significantly. Grazing X-ray diffraction, high-resolution microscopy, energy-dispersive spectrometry and X-ray photoelectron spectroscopy describe the outer surface layer as a poly- and nanocrystalline ZnS blende shell whose thickness and roughness increase with t c. The ZnO wurtzite-ZnS blende interface goes from continuous and dense, at short t c, to discontinuous and porous at long t c, indicating that ZnS formation proceeds in a more complex way than a simple S2-/O2- ion exchange over the treatment time. This feature has significant consequences for the photoelectrochemical performance of these materials when they are used as photoanodes in a typical light-assisted water splitting experiment. A photocurrent (J p) fluctuation of 45% for less than 5 min of operation is observed for the sample prepared with a long sulfidation time while it does not exceed 15% for that obtained with a short one, underlining the importance of the material processing conditions on the preparation of valuable photoanodes.

17.
J Dent Res ; 96(11): 1314-1321, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28767323

RESUMO

Nonsyndromic cleft palate only (nsCPO) is a facial malformation that has a livebirth prevalence of 1 in 2,500. Research suggests that the etiology of nsCPO is multifactorial, with a clear genetic component. To date, genome-wide association studies have identified only 1 conclusive common variant for nsCPO, that is, a missense variant in the gene grainyhead-like-3 ( GRHL3). Thus, the underlying genetic causes of nsCPO remain largely unknown. The present study aimed at identifying rare variants that might contribute to nsCPO risk, via whole-exome sequencing (WES), in multiply affected Central European nsCPO pedigrees. WES was performed in 2 affected first-degree relatives from each family. Variants shared between both individuals were analyzed for their potential deleterious nature and a low frequency in the general population. Genes carrying promising variants were annotated for 1) reported associations with facial development, 2) multiple occurrence of variants, and 3) expression in mouse embryonic palatal shelves. This strategy resulted in the identification of a set of 26 candidate genes that were resequenced in 132 independent nsCPO cases and 623 independent controls of 2 different ethnicities, using molecular inversion probes. No rare loss-of-function mutation was identified in either WES or resequencing step. However, we identified 2 or more missense variants predicted to be deleterious in each of 3 genes ( ACACB, PTPRS, MIB1) in individuals from independent families. In addition, the analyses identified a novel variant in GRHL3 in 1 patient and a variant in CREBBP in 2 siblings. Both genes underlie different syndromic forms of CPO. A plausible hypothesis is that the apparently nonsyndromic clefts in these 3 patients might represent hypomorphic forms of the respective syndromes. In summary, the present study identified rare variants that might contribute to nsCPO risk and suggests candidate genes for further investigation.


Assuntos
Fissura Palatina/genética , Exoma/genética , Europa (Continente) , Feminino , Predisposição Genética para Doença , Variação Genética , Humanos , Masculino , Análise de Sequência de DNA , Iêmen
18.
Diabetes Care ; 7 Suppl 1: 42-6, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6376028

RESUMO

We have examined the nonpancreatic actions of sulfonylureas on multiple aspects of insulin responsiveness in two target tissues for insulin, liver and fat. In vivo administration of tolazamide and glipizide reduced significantly the postabsorptive serum glucose levels in rats without altering the levels of insulin. This was consistent with extrapancreatic sites of drug action. The number and affinity of hepatic insulin receptors was not different from those of control rats. Using a tissue culture system for rat adipose tissue, a 20-h treatment with sulfonylureas markedly potentiated insulin action in fat cells. The primary augmentation was at the level of insulin-stimulated glucose transport. Again, there was no alteration of the insulin receptors located on the adipose tissue. Furthermore, consistent with the lack of an influence on insulin-induced receptor loss after in vitro treatment with sulfonylureas, the in vivo administration of these agents did not alter the transglutaminase activity in rat hepatic tissue. The data demonstrate that sulfonylureas potentiate the responsiveness of the target tissues for insulin. Thus, these hypoglycemic agents probably act by correcting some of the cellular lesions associated with the insulin resistance in type II diabetes mellitus.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Insulina/fisiologia , Fígado/efeitos dos fármacos , Compostos de Sulfonilureia/farmacologia , Animais , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Radioisótopos do Iodo , Ratos , Receptor de Insulina/efeitos dos fármacos , Tolazamida/farmacologia
20.
Dalton Trans ; 44(36): 16013-23, 2015 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-26285686

RESUMO

New hybrid compounds LnCoCl(deg)2 (deg = diethyleneglycolate; Ln = Nd, Sm, Eu, Gd and Ho) have been synthesized by mixing cobalt and rare earth cations in a boiling diethyleneglycol (degH2) medium. Their crystallographic structures have been ab initio solved from synchrotron powder diffraction data. They consist of edge sharing tetrameric sub-units [(Ln2Co2)(deg)4(Cl)2] forming 1D infinite chains along the c parameter of a monoclinic unit cell (SG = C2/c). The five- and seven-coordination of Co(2+) and Ln(3+) cations inferred from the crystallographic results is confirmed by UV-visible absorption and Extended X-ray Absorption Fine Structure (EXAFS) spectroscopy. In the LnCoCl(deg)2 (Ln = Nd, Sm, Eu, Gd, Ho) series, weak antiferromagnetic superexchange interactions have been evidenced, between high spin Co(2+) and Ln(3+) orbitally degenerate cations. These materials are considered as potential precursors for the simultaneous reduction of Co-Ln-glycolate species into bimetallic nanoparticles by the polyol process.

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