Diffusion on random site percolation clusters. Theory and NMR microscopy experiments with model objects

Quasi two-dimensional random site percolation model objects were fabricate based on computer generated templates. Samples consisting of two compartments, a reservoir of H$_2$O gel attached to a percolation model object which was initially filled with D$_2$O, were examined with NMR (nuclear magnetic resonance) microscopy for rendering proton spin density maps. The propagating proton/deuteron inter-diffusion profiles were recorded and evaluated with respect to anomalous diffusion parameters. The deviation of the concentration profiles from those expected for unobstructed diffusion directly reflects the anomaly of the propagator for diffusion on a percolation cluster. The fractal dimension of the random walk, $d_w$, evaluated from the diffusion measurements on the one hand and the fractal dimension, $d_f$, deduced from the spin density map of the percolation object on the other permits one to experimentally compare dynamical and static exponents. Approximate calculations of the propagator are given on the basis of the fractional diffusion equation. Furthermore, the ordinary diffusion equation was solved numerically for the corresponding initial and boundary conditions for comparison. The anomalous diffusion constant was evaluated and is compared to the Brownian case. Some ad hoc correction of the propagator is shown to pay tribute to the finiteness of the system. In this way, anomalous solutions of the fractional diffusion equation could experimentally be verified for the first time.Comment: REVTeX, 12 figures in GIF forma

A model for the generic alpha relaxation of viscous liquids

Dielectric measurements on molecular liquids just above the glass transition indicate that alpha relaxation is characterized by a generic high-frequency loss varying as $\omega^{-1/2}$, whereas deviations from this come from one or more low-lying beta processes [Olsen et al, Phys. Rev. Lett. {\bf 86} (2001) 1271]. Assuming that long-wavelength fluctuations dominate the dynamics, a model for the dielectric alpha relaxation based on the simplest coupling between the density and dipole density fields is proposed here. The model, which is solved in second order perturbation theory in the Gaussian approximation, reproduces the generic features of alpha relaxation

Geometrical restrictions of water diffusion in aqueous protein systems. A study using NMR field-gradient techniques

Geometrical restrictions of water diffusion in different aqueous protein systems were studied using two versions of the NMR field gradient technique. The samples were aqueous systems of bovine serum albumin, gelatin and horse myoglobin at concentrations ranging from diluted solutions to almost dry powders being only partly hydrated. Hydrated protein aerogels were produced by the aid of a special preparation procedure and studied in addition. The experiments referred to the, temperature and concentration dependences of the water diffusion coefficient above and below the free-water freezing temperature. The diffusion coefficient within clusters of overlapping hydration shells is reduced by one order of magnitude compared with that of bulk water. Geometrical restrictions manifest themselves (a) by the obstruction effect observed at low protein concentrations, (b) by the topologically two-dimensional diffusion in the network of overlapping hydration shells, (c) by the percolation threshold appearing at about 15%b.w. water and (d) by the anomalous diffusion behaviour concluded from the protein aerogel study. © 1993 Springer

Pomalidomide and dexamethasone grant rapid haematologic responses in patients with relapsed and refractory AL amyloidosis: a European retrospective series of 153 patients

Pomalidomide demonstrated activity in the treatment of AL amyloidosis in three phase II clinical trials. We evaluated the safety and efficacy of 28-day cycles of pomalidomide and dexamethasone in 153 previously treated patients with systemic AL amyloidosis. Ninety-nine (65%) were refractory to the last line of therapy and 54 (35%) had relapsed. The median number of previous lines of therapy was 3 (range: 2–7): 143 patients (93%) previously received bortezomib, 124 (81%) lenalidomide, 114 (75%) oral melphalan, and 37 (24%) underwent autologous stem cell transplant. At the completion of cycle 6, 68 (44%) patients obtained at least partial haematologic response, with 5 complete responses (CR, 3%), 35 very good partial responses (VGPR, 23%). Haematologic response resulted in improved overall survival (median survival 50 vs. 27 months, p = .033) in a 6 months landmark analysis. Obtaining at least partial response was also associated with a significant improvement of the progression-free survival (median PFS 37 vs. 18 months, p < .001). Pomalidomide is an effective treatment for heavily pre-treated patients with AL amyloidosis. Haematologic responses are associated with an overall survival advantage

Epidemiological, clinical and genetic aspects of adult onset isolated focal dystonia in Ireland

Background: Adult onset idiopathic isolated focal dystonia presents with a number of phenotypes. Reported prevalence rates vary considerably; well-characterized cohorts are important to our understanding of this disorder. Aim: To perform a nationwide epidemiological study of adult onset idiopathic isolated focal dystonia in the Republic of Ireland. Methods: Patients with adult onset idiopathic isolated focal dystonia were recruited from multiple sources. Diagnosis was based on assessment by a neurologist with an expertise in movement disorders. When consent was obtained, a number of clinical features including family history were assessed. Results: On the prevalence date there were 592 individuals in Ireland with adult onset idiopathic isolated focal dystonia, a point prevalence of 17.8 per 100 000 (95% confidence interval 16.4-19.2). Phenotype numbers were cervical dystonia 410 (69.2%), blepharospasm 102 (17.2%), focal hand dystonia 39 (6.6%), spasmodic dysphonia 18 (3.0%), musician\u27s dystonia 17 (2.9%) and oromandibular dystonia six (1.0%). Sixty-two (16.5%) of 375 consenting index cases had a relative with clinically confirmed adult onset idiopathic isolated focal dystonia (18 multiplex and 24 duplex families). Marked variations in the proportions of patients with tremor, segmental spread, sensory tricks, pain and psychiatric symptoms by phenotype were documented. Conclusions: The prevalence of adult onset idiopathic isolated focal dystonia in Ireland is higher than that recorded in many similar service-based epidemiological studies but is still likely to be an underestimate. The low proportion of individuals with blepharospasm may reflect reduced environmental exposure to sunlight in Ireland. This study will serve as a resource for international comparative studies of environmental and genetic factors in the pathogenesis of the disorder

Lung Metastasis of Primary Alveolar Soft-Part Sarcoma Occurring 20 Years after Initial Treatment

A 30-year old woman was referred to our center because of suspicion of a primary lung tumor of the right upper lobe. Histological examination of the lung lesion revealed lung metastasis of a previously treated alveolar soft part sarcoma of the musculus vastus medialis of the right femur, which was resected 20 years ago. Alveolar soft-part sarcoma is a rare malignant tumor that occurs most often in the soft tissue of lower limbs. It is a slow-growing malignant soft tissue tumor arising in muscle tissue, usually in young adults. Due to pleural and extensive mediastinal infiltration with bilateral lung metastases, a systemic treatment with chemotherapy doxorubicin and ifosfamide was initiated. Late metastases from previously treated alveolar part sarcoma should be considered in patients with suspicious lung lesions even if surgical treatment was performed a long time ago

Propagación vegetativa de procedencias de Tithonia diversifolia (Hemsl) A. Gray en el Noreste de Argentina = Vegetative propagation of Tithonia diversifolia (Hemsl) A. Gray provenances in northeast Argentina

El objetivo del trabajo fue comparar sobrevivencia y crecimiento de tres procedencias y dos tipos de estaca de Botón de oro durante la etapa de propagación vegetativa en vivero. Se establecieron tres ensayos en red en la estación experimental de INTA Cerro Azul (Misiones), Campo Anexo Laharrague de INTA Montecarlo (Misiones) y en la Universidad del Salvador Sede Gdor. Virasoro, Corrientes. El diseño fue factorial con arreglo en BCA y cinco repeticiones. El factor procedencia con tres niveles: México, Brasil y Colombia y el factor tipo de estaca con dos niveles: basal y sub-apical. Los tratamientos fueron: CoA (Colombia apical), CoB (Colombia basal), BrA (Brasil apical), BrB (Brasil basal), MeA (México apical) y MeB (México basal). Se evaluó en las estacas (previo a la plantación): número de nudos, diámetro total (cm), diámetro de médula (cm) y peso (g), en vivero: sobrevivencia y prendimiento de brotes y altura máxima de planta a los 7, 15, 30 y 40 días y al finalizar el período se cosechó la biomasa aérea y subterránea. La menor sobrevivencia de plantas fue para MeA (84%) y MeB (90%). La mayor altura para BrB (70,16 cm) y el mayor número de brotes para BrB, BrA y CoA (2,2; 2,3 y 2,4). La biomasa total medida en Virasoro y Cerro Azul fue mayor para BrB (12,47 y 9,83 g MS planta-1 en ambos sitios). Las procedencias Brasil y Colombia presentaron los mayores valores de sobrevivencia, crecimiento en altura, número de brotes y producción de biomasa, por lo cual pueden ser consideradas más promisorias para la región de estudio.The aim of this work was to compare survival rate and growth of “Botón de oro” of three provenances and two cutting types in the vegetative propagation period in greenhouse. Three experiments were established at 216 INTA experimental station Cerro Azul (Misiones), INTA experimental field Laharrague (Montecarlo, Misiones) and Universidad Del Salvador, Gobernador Virasoro, Corrientes. The experimental design was factorial with CRB arrangement and five replicates. The origins were Mexico, Brazil and Colombia and cutting types were basal and sub-apical. The treatments results: CoA (Colombia apical, CoB (Colombia basal), BrA (Brazil apical), BrB (Brazil basal), MeA (Mexico apical) and MeB (Mexico basal). In cutting (before plantation): nodes number, total diameter (cm), marrow diameter (cm) and weight (g) were measured. In greenhouse: survival rate, sprout number and height at 7, 15, 30 and 40 days and at the end aerial and underground biomass were assessed. The lowest survival rate was for MeA (84%) and MeB (90%). The main height was for BrB (70,16cm) and the highest sprouts number were for BrB, BrA and CoA (2.2;2.3 and 2.4). The highest biomass was for BrB (12.47and 9.83g plant-1). Brazil and Colombia origins showed the best values for survival rate, height, sprouts number and biomass production, being the most adapted origins for the study region.EEA MontecarloFil: Rossner, Maria Belen. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Cerro Azul; ArgentinaFil: Ziegler, Ariana. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Cerro Azul. Agencia de Extensión Rural Apóstoles; ArgentinaFil: González, Paola. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Montecarlo; ArgentinaFil: Loto, Mauro. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Montecarlo; ArgentinaFil: Kimmich, Germán. Universidad del Salvador. Facultad de Ciencias Agrarias Virasoro; ArgentinaFil: Corró, Federico. Universidad del Salvador. Facultad de Ciencias Agrarias Virasoro; ArgentinaFil: Fernández, F. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Cerro Azul. Agencia de Extensión Rural Apóstoles; Argentin

Gaussian Process-based prediction of memory performance and biomarker status in ageing and Alzheimer's disease-A systematic model evaluation

Neuroimaging markers based on Magnetic Resonance Imaging (MRI) combined with various other measures (such as genetic covariates, biomarkers, vascular risk factors, neuropsychological tests etc.) might provide useful predictions of clinical outcomes during the progression towards Alzheimer's disease (AD). The use of multiple features in predictive frameworks for clinical outcomes has become increasingly prevalent in AD research. However, many studies do not focus on systematically and accurately evaluating combinations of multiple input features. Hence, the aim of the present work is to explore and assess optimal combinations of various features for MR-based prediction of (1) cognitive status and (2) biomarker positivity with a multi kernel learning Gaussian process framework. The explored features and parameters included (A) combinations of brain tissues, modulation, smoothing, and image resolution;(B) incorporating demographics & clinical covariates;(C) the impact of the size of the training data set;(D) the influence of dimensionality reduction and the choice of kernel types. The approach was tested in a large German cohort including 959 subjects from the multicentric longitudinal study of cognitive impairment and dementia (DELCODE). Our evaluation suggests the best prediction of memory performance was obtained for a combination of neuroimaging markers, demographics, genetic information (ApoE4) and CSF biomarkers explaining 57% of outcome variance in out-of sample predictions. The highest performance for A 42/40 status classification was achieved for a combination of demographics, ApoE4, and a memory score while usage of structural MRI further improved the classification of individual patient's pTau status