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Relaxation of magnetization in endohedral metallofullerenes DySc2N@C80 is studied at different temperatures, in different magnetic fields, and in different molecular arrangements. Magnetization behavior and relaxation are analyzed for powder sample, and for DySc2N@C80 diluted in non-magnetic fullerene Lu3N@C80, adsorbed in voids of a metal-organic framework, and dispersed in a polymer. The magnetic field dependence and zero-field relaxation are also studied for single-crystals of DySc2N@C80 co-crystallized with Ni(ii) octaethylporphyrin, as well as for the single crystal diluted with Lu3N@C80. Landau-Zener theory is applied to analyze quantum tunneling of magnetization in the crystals. The field dependence of relaxation rates revealed a dramatic dependence of the zero-field tunneling resonance width on the dilution and is explained with the help of an analysis of dipolar field distributions. AC magnetometry is used then to get access to the relaxation of magnetization in a broader temperature range, from 2 to 87 K. Finally, a theoretical framework describing the spin dynamics with dissipation is proposed to study magnetization relaxation phenomena in single molecule magnets.
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Advances in flexible and functional metal-organic frameworks (MOFs), also called soft porous crystals, are reviewed by covering the literature of the five years period 2009-2013 with reference to the early pertinent work since the late 1990s. Flexible MOFs combine the crystalline order of the underlying coordination network with cooperative structural transformability. These materials can respond to physical and chemical stimuli of various kinds in a tunable fashion by molecular design, which does not exist for other known solid-state materials. Among the fascinating properties are so-called breathing and swelling phenomena as a function of host-guest interactions. Phase transitions are triggered by guest adsorption/desorption, photochemical, thermal, and mechanical stimuli. Other important flexible properties of MOFs, such as linker rotation and sub-net sliding, which are not necessarily accompanied by crystallographic phase transitions, are briefly mentioned as well. Emphasis is given on reviewing the recent progress in application of in situ characterization techniques and the results of theoretical approaches to characterize and understand the breathing mechanisms and phase transitions. The flexible MOF systems, which are discussed, are categorized by the type of metal-nodes involved and how their coordination chemistry with the linker molecules controls the framework dynamics. Aspects of tailoring the flexible and responsive properties by the mixed component solid-solution concept are included, and as well examples of possible applications of flexible metal-organic frameworks for separation, catalysis, sensing, and biomedicine.
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The ultrahigh porosity and varied functionalities of porous metal-organic frameworks make them excellent candidates for applications that range widely from gas storage and separation to catalysis and sensing. An interesting feature of some frameworks is the ability to open their pores to a specific guest, enabling highly selective separation. A prerequisite for this is bistability of the host structure, which enables the framework to breathe, that is, to switch between two stability minima in response to its environment. Here we describe a porous framework DUT-8(Ni)-which consists of nickel paddle wheel clusters and carboxylate linkers-that adopts a configurationally degenerate family of disordered states in the presence of specific guests. This disorder originates from the nonlinear linkers arranging the clusters in closed loops of different local symmetries that in turn propagate as complex tilings. Solvent exchange stimulates the formation of distinct disordered frameworks, as demonstrated by high-resolution transmission electron microscopy and diffraction techniques. Guest exchange was shown to stimulate repeatable switching transitions between distinct disorder states.
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INTRODUCTION: The need for ophthalmologist appointments is increasing, while the number of practitioners is decreasing. Elderly patients, who may be dependent and isolated, are the most affected by this barrier to care. In order to get around this obstacle, telemedicine visits might be an alternative. MATERIALS AND METHODS: From June 2018 to November 2018, patients in the housing facility for dependent elderly individuals (EHPAD) at the Janzé (Ille-et-Vilaine) Medical Centre participated in an ophthalmology telemedicine visit during their stay. The telemedicine visit included measurement of visual acuity, intraocular pressure, wide field fundus photography, and optical coherence tomography (OCT) performed by a technician, and a videoconference with an ophthalmologist. RESULTS: Sixty-seven patients aged 83±8 years (60% women and 40% men) underwent a telemedicine visit. The visit was completed in 36 (54%) cases. The fundus photography was not performed in 30 (45%) cases, and the OCT was not performed in 35 (53%) cases. We diagnosed an ophthalmologic disease in 37 (55%) patients, with medical management having begun in 14 (38%) of them. A prescription for corrective lenses was given in 30 patients (45%). Following our visit, mean logMar visual acuity experienced a statistically significant improvement from 0.67 (±0.76) to 0.52 (±0.72) (P<0.0001) for distance vision and from 0.68 (±0.84) to 0.53 (±0.76) (P<0.0001) for near vision. Eighteen per cent of patients (10) required transportation to an in-person ophthalmologist visit for continued management. With regard to low vision, the proportion of low-vision eyes experienced a statistically significant decrease from 54% to 39% [P=0.02; OR=1.86; 95% CI (1.06-3.28)] following our visit. DISCUSSION: This experiment allowed an isolated, dependent patient population without access to classic office visits to gain access to clinical care. In addition to providing eye care to the patients, the visit increased awareness amongst the caregivers of the vision status of the residents, allowing them to adapt their environment accordingly. CONCLUSION: Telemedicine is an alternative to classic physician visits, particularly for very dependent, institutionalised patients. This experiment might serve as a point of departure for generalised adoption of these solutions within extended care facilities.
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Oftalmología , Telemedicina , Anciano , Retroalimentación , Femenino , Humanos , Masculino , Casas de Salud , Instituciones de Cuidados Especializados de EnfermeríaRESUMEN
INTRODUCTION: AMD follow-up is a public health issue in developed countries due to aging of the population and medical demographics. Telemedicine may be a means of improving follow-up. PURPOSE: To compare the agreement between telemedicine and in-person consultations in terms of indications for intravitreal injections in exudative AMD patients. MATERIALS AND METHODS: From January 2017 to April 2017, AMD patients followed on a PRN protocol at a single center, Rennes university medical center, were included. The telemedicine evaluation was read by two anonymous experts on the basis of the medical record including visual acuity and fundus photographs. The agreement between conventional follow-up and telemedicine in terms of indications for intravitreal injections, as well as interobserver agreement, were tested with the Cohen's kappa coefficient using SAS statistical software V9.4 (SAS Institute, Cary, NC). RESULTS: In total, 104 eyes corresponding to 57 consultations for 42 patients were analyzed. The mean age was 82.12 years (standard deviation±6.4). Recommendations for anti-VEGF were similar between the standard and telemedicine visits in 97 % of cases. The Kappa coefficient was 0.8861 [0.76; 1.00], P<0.0001 for agreement between telemedicine and in-person consultation. The Kappa coefficient was 0.8441 [0.70; 0.99], P<0.0001 for interobserver agreement. We observed 5 cases of disagreement between the two observers. DISCUSSION: The concordance was very good in our study. The few cases of disagreement resulted mainly from poorly interpretable examinations due to poor image quality, major macular changes in patients with a prior examination, and the fact that only a single cut was analyzed. CONCLUSION: AMD monitoring by telemedicine seems promising and reliable. This approach would allow better follow-up of patients with difficult access to care.
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Telemedicina , Degeneración Macular Húmeda , Anciano de 80 o más Años , Inhibidores de la Angiogénesis/uso terapéutico , Estudios de Seguimiento , Humanos , Inyecciones Intravítreas , Ranibizumab , Estudios Retrospectivos , Degeneración Macular Húmeda/tratamiento farmacológicoRESUMEN
INTRODUCTION: Ophthalmologic care needings increase whereas the numbers of ophthalmologist decrease. Oldest people who are often vulnerable and dependent populations are particularly affected in difficulty to access to health services. To resolve the problem, the use of telemedicine in ophthalmology could be an alternative. MATERIALS AND METHODS: From June 2018 to November 2018, patients from Janzé Hospital (Ille et Vilaine) did an ophthalmologic teleconsultation during their stay. Teleconsultation was based on visual acuity, intraocular pressure measurement, wild-field retinophotography and optical coherence tomography performed by an orthoptist and a videoconference with an ophthalmologist. RESULTS: Sixty-seven patients underwent teleconsultation (60 % women, 40 % men). Mean age was 83 (standard deviation±8). Fifty-four percent (36) of consultations were complete. Retinophotography was missing in 45 % of cases (30) and optical coherence tomography in 53 % of cases (35). Ophtalmologic pathologies were detected in 37 patients (55 %) and we start medical care in 14 (38 %) of the patients. We gave glasses prescription to 45 % (30) of the patients. Eighteen percent (10) of the patients required a physical consultation. LogMar distance visual acuity was significantly improved from 0.67 (±0.76) to 0.52 (±0.72) (P<0.0001) and LogMar near visual acuity was significantly improved from 0.68 (±0.84) to 0.53 (±0.76) (P<0.0001). Low vision proportion was significantly decreased from 54 % to 39 % (P=0.02; OR=1.86; IC95 % [1.06-3.28]) after our intervention. DISCUSSION: This experiment gives the opportunity to old, vulnerable and dependent population that has no longer access to classical consultation to access eye care. At the same time, consultation informs the nursing home caregivers about the visual health status and provides environment improvement. CONCLUSION: Teleconsultation is an alternative to classical consultation especially in dependent population. This experiment could be a starting point to the development of this solution in social health-care institutions.
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Hogares para Ancianos , Casas de Salud , Oftalmología , Telemedicina , Anciano , Anciano de 80 o más Años , Retroalimentación , Femenino , Francia/epidemiología , Hogares para Ancianos/organización & administración , Humanos , Masculino , Tamizaje Masivo/métodos , Tamizaje Masivo/organización & administración , Casas de Salud/organización & administración , Oftalmología/métodos , Oftalmología/organización & administración , Medicina Preventiva/métodos , Medicina Preventiva/organización & administración , Consulta Remota/métodos , Consulta Remota/organización & administración , Estudios Retrospectivos , Telemedicina/métodos , Telemedicina/organización & administración , Baja Visión/diagnóstico , Baja Visión/epidemiología , Agudeza VisualRESUMEN
In the title compound, [PdCl(2)(C(7)H(9)N)(2)], the Pd atom is situated on an inversion centre and displays a distorted square-planar coordination environment. The crystal structure displays weak inter-molecular N-Hâ¯Cl hydrogen bonding.
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The title compound, [Zn(C(2)H(8)NO(6)P(2))(2)(H(2)O)(4)]·4H(2)O, was synthesized by the reaction of ZnCl(2) with 1-amino-ethane-1,1-diyldiphospho-nic acid in aqueous solution. The asymmetric unit contains one-half of the complex and two water mol-ecules of solvation. The Zn atom occupies a special position on an inversion centre. This results in a slightly distorted octa-hedral coordination environment, which consists of the O atoms from two phospho-nic acids and four water mol-ecules. The crystal structure displays N-Hâ¯O and O-Hâ¯O hydrogen bonding, which creates a three-dimensional network.
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The title compound, NH(4) (+)·C(2)H(8)NO(6)P(2) (-)·2H(2)O, was obtained by the reaction between 1-amino-ethane-1,1-diyldiphospho-nic acid and ammonium hydroxide (1:1) in an aqueous solution. The asymmetric unit contains one anion with two H atoms transferred from the phospho-nic acid groups to the amino group of the anion and to an ammonia mol-ecule, giving an ammonium cation. The structure displays N-Hâ¯O and O-Hâ¯O hydrogen bonding, which creates a three-dimensional network.
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The title compound, H(3)O(+)·C(4)H(10)NO(6)P(2) (-)·H(2)O, was obtained from the reaction of cyclo-propane-carbonitrile with PCl(3), followed by dropwise addition of water. The asymmetric unit comprises an oxonium cation, a zwitterionic monoanion containing a positively charged ammonium group and two negatively charged phospho-nic acid residues and a water mol-ecule of crystallization. The hydroxonium cation and water mol-ecule are hydrogen bonded to the anion and further N-Hâ¯O and O-Hâ¯O bonds create a three-dimensional network.
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The title compound, C(5)H(15)NO(6)P(2), was obtained by the reaction of penta-nenitrile with PCl(3) followed by the dropwise addition of water. The asymmetric unit contains one mol-ecule, which exists as a zwitterion with a positive charge on the -NH(3) group and a negative charge on one of the phospho-nic O atoms. The crystal structure displays N-Hâ¯O and O-Hâ¯O hydrogen bonding, which creates a three-dimensional network.
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The syntheses and crystal structures of the fluorinated linker 1,4-bis(3,5-bis(trifluoromethyl)-1H-pyrazole-4-yl)benzene (H2-tfpb; 1) and the novel metal-organic framework family M[CFA-4] (Coordination Framework Augsburg University-4), M[Cu5(tfpb)3] (M = Cu(i), K, Cs, Ca(0.5)), are described. The ligand 1 is fully characterized by single crystal X-ray diffraction, photoluminescence-, NMR-, IR spectroscopy, and mass spectrometry. The copper(i)-containing MOF crystallizes in the hexagonal crystal system within the chiral space group P6322 (no. 182) and the unit cell parameters are as follows: a = 23.630(5) Å, c = 41.390(5) Å, V = 20 015(6) Å3. M[CFA-4] features a porous 3-D structure constructed from pentanuclear copper(i) secondary building units {Cu(pz)6}- (pz = pyrazolate). Cu(I)[CFA-4] is fully characterized by synchrotron single crystal X-ray diffraction, thermogravimetric analysis, variable temperature powder X-ray diffraction, IR spectroscopy, photoluminescence and gas sorption measurements. Moreover, thermal stability and gas sorption properties of K[CFA-4] and Cu(I)[CFA-4] are compared.
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The microbiological control of the environment is a real issue inside the pharmaceutical production plants. Actually the most used methods are the Contact Plates and the Swabs. The purpose of this study is to evaluate the performance of a new "ready to use" method called Petrifilm SM (produced by 3M Laboratories). Petrifilm consists of a dry-rehydratable growth medium coated on a flexible film. Petrifilm is tested in comparison with Swabs and Contact Plates to monitor the microbiological pollution on labs surfaces and operator's overalls. The results obtained are comparable with the above mentioned methods, but with important advantages being less bulky, considerably time saving and highly reproducible. Hence, we think that Petrifilm S, can be successfully used instead of the other two more traditional methods.
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Bacterias Anaerobias/aislamiento & purificación , Exposición Profesional , Ropa de Protección , Medios de CultivoRESUMEN
BACKGROUND: The prehospital use of adenosine in the treatment of supraventricular arrhythmias has recently been implemented in standard ambulance care. However, establishing the origin and nature of the arrhythmia with certainty is an absolute requirement for using adenosine. METHODS: The ability of the ambulance nurse to predict supraventricular arrhythmias and the necessity of prehospital treatment of arrhythmias in general was evaluated. To do this, cardiologists at the Academic Medical Centre of Amsterdam were consulted and a literature search by means of an electronic search in Pubmed was performed. The search was complemented by a second survey concerning antagonists of adenosine using the keywords: adenosine and theophylline. Moreover, the Ambulance Nurse textbook, the National Protocol for Ambulance Care as well as the explanatory memorandum to the protocol were consulted. RESULTS: No strong indication for the prehospital use of adenosine was found, while detrimental effects of the drug can occur. There is no literature showing the ability of ambulance staff to correctly interpret complex cardiac arrhythmias in the Netherlands; the current ambulance protocol does not prevent an incorrect choice of therapy and medication. CONCLUSION: It is strongly advised against using antiarrhythmic medication for the treatment of tachycardias in a prehospital setting if this treatment can be postponed to the hospital environment.
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Neoplasias Orbitales/diagnóstico , Plasmacitoma/diagnóstico , Anciano , Humanos , MasculinoRESUMEN
Recent discoveries that high prolificacy in sheep carrying the Booroola gene (FecB) is the result of a mutation in the BMPIB receptor and high prolificacy in Inverdale sheep (FecX(I)) is the result of a mutation in the BMP15 oocyte-derived growth factor gene have allowed direct marker tests to be developed for FecB and FecX(I). These tests were carried out in seven strains of sheep (Javanese, Thoka, Woodlands, Olkuska, Lacaune, Belclare, and Cambridge) in which inheritance patterns have suggested the presence of major genes affecting prolificacy and in the prolific Garole sheep of India, which have been proposed as the ancestor of Australian Booroola Merinos. The FecB mutation was found in the Garole and Javanese sheep but not in Thoka, Woodlands, Olkuska, Lacaune, Belclare, and Cambridge sheep. None of the sheep tested had the FecX(I) mutation. These findings present strong evidence to support historical records that the Booroola gene was introduced into Australian flocks from Garole (Bengal) sheep in the late 18th century. It is unknown whether Javanese Thin-tailed sheep acquired the Booroola gene directly from Garole sheep from India or via Merinos from Australia. The DNA mutation test for FecB will enable breeding plans to be developed that allow the most effective use of this gene in Garole and Javanese Thin-tailed sheep and their crosses.
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ADN/análisis , Proteínas de Escherichia coli/genética , Bombas Iónicas/genética , Mutación , Ovulación/genética , Reproducción/genética , Ovinos/genética , Animales , Australia , Femenino , Genotipo , India , Tamaño de la Camada/genética , Polimorfismo de Longitud del Fragmento de Restricción , Polimorfismo Conformacional Retorcido-Simple , Especificidad de la EspecieAsunto(s)
Catecolaminas/orina , Ritmo Circadiano , Hipertensión/orina , Adulto , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
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