Biophysical modelling of a drosophila photoreceptor

It remains unclear how visual information is co-processed by different layers of neurons in the retina. In particular, relatively little is known how retina translates vast environmental light changes into neural responses of limited range. We began examining this question in a bottom-up way in a relatively simple °y eye. To gain understanding of how complex bio-molecular interactions govern the conversion of light input into voltage output (phototransduction), we are building a biophysical model of the Drosophila R1-R6 photoreceptor. Our model, which relates molecular dynamics of the underlying biochemical reactions to external light input, attempts to capture the molecular dynamics of phototransduction gain control in a quantitative way

Model term selection for spatio-temporal system identification using mutual information

A new mutual information based algorithm is introduced for term selection in spatio-temporal models. A generalised cross validation procedure is also introduced for model length determination and examples based on cellular automata, coupled map lattice and partial differential equations are described

Data production models for the CDF experiment

The data production for the CDF experiment is conducted on a large Linux PC farm designed to meet the needs of data collection at a maximum rate of 40 MByte/sec. We present two data production models that exploits advances in computing and communication technology. The first production farm is a centralized system that has achieved a stable data processing rate of approximately 2 TByte per day. The recently upgraded farm is migrated to the SAM (Sequential Access to data via Metadata) data handling system. The software and hardware of the CDF production farms has been successful in providing large computing and data throughput capacity to the experiment.Comment: 8 pages, 9 figures; presented at HPC Asia2005, Beijing, China, Nov 30 - Dec 3, 200

Pt(II) coordination complexes as visible light photocatalysts for the oxidation of sulfides using batch and flow processes

A new catalytic system for the photooxidation of sulfides based on Pt(ii) complexes is presented. The catalyst is capable of oxidizing a large number of sulfides containing aryl, alkyl, allyl, benzyl, as well as more complex structures such as heterocycles and methionine amino acid, with complete chemoselectivity. In addition, the first sulfur oxidation in a continuous flow process has been developedJ. A. would also like to thank the MICINN for their ‘Ramón y Cajal’ contract and the European Research Council (ERC-CG, contract number 647550

Report of the International Society of Hypertension (ISH) Hypertension Teaching Seminar organized by the ISH Africa Regional Advisory Group: Maputo, Mozambique, 2016

The International Society of Hypertension (ISH), in fulfilment of its mission of promoting hypertension control and prevention and also of advancing knowledge globally, organizes hypertension teaching seminars or ‘summer schools’ worldwide through the ISH Regional Advisory Groups. In Africa, seven of such seminars have been organized. This is a report of the eighth seminar held in Maputo, Mozambique, April, 2016. The seminar was attended by over 65 participants from 11 African countries. The Faculty consisted of 11 international hypertension experts. The eighth African hypertension seminar was a great success as confirmed by a pre- and post-test questionnaire

La regeneración del pinsapar en la sierra de Grazalema. I: análisis de la fase de plántula

Se estudia la dinámica de la regeneración del pinsapar en la Sierra de Grazalema. Previamente se ha llevado a cabo una diferenciación del conjunto del pinsapar a partir de la información disponible de inventarios, fotointerpretación, bibliografía y datos de campo, dando como resultados cuatro tipos estructurales: Pinsapar puro estructurado, Pinsapar puro latizal-fustal, Quejigal con pinsapos y Encinar con pinsapos. En este estudio, el análisis del proceso de regeneración se centra en el regenerado en estado de plántula, donde la mortalidad puede tener una incidencia enorme debida especialmente a la sequía estival propia del ámbito mediterráneo. Se ha establecido un dispositivo de muestreo sistemático en los cuatro estratos, medido una vez finalizada la germinación de semillas del año y después del verano. Con los datos obtenidos se ha estudiado tanto la incorporación, como la mortalidad de nuevas plántulas. Se han encontrado diferencias significativas entre los estratos de pinsapar puro y los mixtos, tanto en incorporación de nuevas plántulas como en mortalidad. También existen diferencias dentro de los dos estratos de pinsapar pur

La regeneración del pinsapar en la sierra de Grazalema. II: estructura y dinámica del regenerado consolidado en el pinsapar puro

En los tipos estructurales de pinsapar puro, se estudia la dinámica y la estructura del regenerado consolidado (plantas de más de un año de edad que no alcanzan las dimensiones de los pies menores, es decir, menos de 1,5 m de altura). El motivo de separar este grupo del de plántulas menores de un año, estriba en las diferentes posibilidades de supervivencia de uno y otro estado ya que en el regenerado consolidado va a depender en mayor medida del grado de competencia al que se vea sometido que de las condiciones locales del medio en que se asienta. El análisis de la distribución de alturas por clases muestra importantes diferencias significativas entre ambos estratos de pinsapar puro, para la clase < 15 cm pero no para las demás clases. Se ha analizado la evolución de la densidad del regenerado por clases de altura desde la fase de plántula hasta la de pie menor, obteniendo una gráfica descendente similar en ambos estratos con una caída brusca inexplicada en la clase de 100 a 150 cm, seguida de una subida en la clase de pies menores atribuida al estancamiento en el crecimiento en altura. El estudio de la relación altura edad demuestra que ésta es significativa, para el regenerado, pero no para los pies menores, indicando así que este grupo se compone de árboles dominados de numerosas y muy distintas edades. El regenerado consolidado constituye una reserva de regeneración a la espera, cuyos individuos aprovecharían las perturbaciones en la estructura para prosperar. Puede decirse que en las circunstancias actuales y frente a perturbaciones no catastróficas, la persistencia del pinsapar está asegurad

Isotropic wave turbulence with simplified kernels: Existence, uniqueness, and mean-field limit for a class of instantaneous coagulation-fragmentation processes

The isotropic 4-wave kinetic equation is considered in its weak formulation using model (simplified) homogeneous kernels. Existence and uniqueness of solutions is proven in a particular setting where the kernels have a rate of growth at most linear. We also consider finite stochastic particle systems undergoing instantaneous coagulation-fragmentation phenomena and give conditions in which this system approximates the solution of the equation (mean-field limit)

Partitioning of trace elements in a entrained flow IGCC plant: Influence of selected operational conditions

The partitioning of trace elements and the influence of the feed conditions (50:50 coal/pet-coke feed blend and limestone addition) was investigated in this study. To this end feed fuel, fly ash and slag samples were collected under different operational conditions at the 335 MW Puertollano IGCC power plant (Spain) and subsequently analysed. The partitioning of elements in this IGCC plant may be summarised as follows: (a) high volatile elements (70–>99% in gas phase): Hg, Br, I, Cl and S; (b) moderately volatile elements (up to 40% in gas phase and 60% in fly ash): As, Sb, Se, B, F, Cd, Tl, Zn and Sn; (c) elements with high condensation potential: (>90% in fly ash): Pb, Ge, Ga and Bi; (d) elements enriched similarly in fly ash and slag 30–60% in fly ash: Cu, W, (P), Mo, Ni and Na; and (e) low volatile elements (>70% in slag): Cs, Rb, Co, K, Cr, V, Nb, Be, Hf, Ta, Fe, U, Ti, Al, Si, Y, Sr, Th, Zr, Mg, Ba, Mn, REEs, Ca and Li. The volatility of As, Sb, and Tl and the slagging of S, B, Cl, Cd and low volatile elements are highly influenced by the fuel geochemistry and limestone dosages, respectively

Marrow adipose tissue expansion coincides with insulin resistance in MAGP1-deficient mice

Marrow adipose tissue (MAT) is an endocrine organ with the potential to influence skeletal remodeling and hematopoiesis. Pathologic MAT expansion has been studied in the context of severe metabolic challenge, including caloric restriction, high fat diet feeding, and leptin deficiency. However, the rapid change in peripheral fat and glucose metabolism associated with these models impedes our ability to examine which metabolic parameters precede or coincide with MAT expansion. Microfibril-associated glycoprotein-1 (MAGP1) is a matricellular protein that influences cellular processes by tethering signaling molecules to extracellular matrix structures. MAGP1-deficient (Mfap2(−/−)) mice display a progressive excess adiposity phenotype, which precedes insulin resistance and occurs without changes in caloric intake or ambulation. Mfap2(−/−) mice were, therefore, used as a model to associate parameters of metabolic disease, bone remodeling, and hematopoiesis with MAT expansion. Marrow adiposity was normal in Mfap2(−/−) mice until 6 months of age; however, by 10 months, marrow fat volume had increased fivefold relative to wild-type control at the same age. Increased gonadal fat pad mass and hyperglycemia were detectable in Mfap2(−/−) mice by 2 months, but peaked by 6 months. The development of insulin resistance coincided with MAT expansion. Longitudinal characterization of bone mass demonstrated a disconnection in MAT volume and bone volume. Specifically, Mfap2(−/−) mice had reduced trabecular bone volume by 2 months, but this phenotype did not progress with age or MAT expansion. Interestingly, MAT expansion in the 10-month-old Mfap2(−/−) mice was associated with modest alterations in basal hematopoiesis, including a shift from granulopoiesis to B lymphopoiesis. Together, these findings indicate MAT expansion is coincident with insulin resistance, but not excess peripheral adiposity or hyperglycemia in Mfap2(−/−) mice; and substantial MAT accumulation does not necessitate a proportional decrease in either bone mass or bone marrow cellularity