Long-term impact of wheat-based cropping systems on soil biological activity

Non-Peer Reviewe

Factors limiting soil microbial growth and activity in wheat-based cropping systems

Non-Peer ReviewedSeveral soil biochemical processes related to soil fertility are microbially mediated. We know very well the factors limiting crop production but know little of the factors limiting the soil microbial community. The goal of this study is to clarify if N, P and C limit soil microbial growth and biochemical processes in the wheat and fallow phases of rotations receiving different N, P and crop residue-C inputs. Soil samples were collected July 28, 2003, and brought to the laboratory. Soils samples were treated with an N, C or P solution, with water only, or left untreated, and incubated for 48 hours. At the end of the incubation period, soil microbial biomass N was determined along with denitrification and nitrogenase activities. The results showed that the microbial activities and growth were limited by soil moisture at the date of sampling. Denitrification and nitrogenase activities were limited by N, P or C. The limiting nutrients varied with N, P and C inputs associated with the cropping system, regardless to soil moisture. The limitation of these elements to soil microbial activity was more frequently encountered under fallow

Understanding microbially mediated processes involved in N, P and C cycling in wheat-based cropping systems

Non-Peer Reviewe

Luxación acromioclavicular: resultados del tratamiento con cerclaje alámbrico sobre agujas de Kirschner

Hemos revisado retrospectivamente 44 pacientes (38 años de edad media) de un total de 57 con luxación acromioclavicular tipo III de Allman intervenidos con la técnica de Phemister modificada desde 1975 hasta 1992. Han sido evaluados desde el punto de vista funcional (escala de Imatani), radiológico, resultado estético, valoración subjetiva del paciente, así como sus complicaciones. La media de seguimiento es de 6 años y medio (rango: 2-17 años). El resultado ha sido excelente en el 89%, bueno en el 9 y malo en el 2. La reducción ha sido anatómica en el 75%. El 91% no presentaron bultoma residual. Subjetivamente el 75% estaban muy contentos o contentos. Las complicaciones más frecuentes han sido la infección superficial y las derivadas del material. Consideramos esta técnica una buena alternativa cuando decidamos realizar tratamiento quirúrgico de estas lesiones. Se debe restringir la movilidad del hombro hasta la retirada del material de osteosíntesis.A series of 44 out of 57 patients with Allman grade III acromioclavicular dislocation operated on from 1975 to 1992 by a modified Phemister technique was studied. Mean age was 38 years. Functional Imatani scale, radiological and aesthetic results, and own patients opinion were considered to evaluate this procedure. Average follow-up was 6 years (range: 2-17 years). Results were considered excellent in 89%, good in 9% and poor in 2%. Anatomical reduction was achieved in 75%. In 91% of cases no clavicular protrusion was observed. A total of 75% were satisfied or very satisfied with their result. Superficial infection and implant failure were found to be the main complications. This technique can be a good procedure when a surgical treatment is considered. Shoulder function must be restricted until the implants have been removed

Estudio epidemiológico de las fracturas trocantéreas en pacientes mayores de 65 años: área de Salud III, Zaragoza

Se presenta un estudio epidemiológico de las fracturas trocantéreas en pacientes mayores de 65 años tratadas en nuestro Servicio y de Cirugía Ortopédica y Traumatología del Hospital Clínico Universitario de Zaragoza entre los años 1980-1993, haciendo hincapié en los últimos 4 años. Como parámetros de referencia hemos utilizado la edad, sexo, lado afectado, mecanismo de producción, clasificación, estancia hospitalaria, demora en la intervención, tratamiento efectuado, mortalidad y morbilidad. Observamos la elevada incidencia de trauma menor en el mecanismo de producción, la inversión del índice cervicotrocantéreo y en general la elevada incidencia en la población a riesgo, lo que han hecho denominar a este tipo de fractura la epidemia del futuro.We have performed an epidemiologic study on the incidence of trocanteric fractures in patients older than 65 years treated at the traumatology unit of the University Clinic Hospital of Zaragoza from 1980 to 1993, insisting on last four years. We have valued age, sex, injurycausing, clasification. length of hospital stay, delay in treatment, in-hospital mortality and morhility. We have observed that injury causing hip fractures were minimal. Gradual inversion in the neck/trochanteric ratio was also detected. In general, we confirmed the high incidence in the population with risk of hip fracture, considering this type of fracture as the epidemy of future

Quark-Squark Alignment Revisited

We re-examine the possibility that the solution to the supersymmetric flavor problem is related to small mixing angles in gaugino couplings induced by approximate horizontal Abelian symmetries. We prove that, for a large class of models, there is a single viable structure for the down quark mass matrix with four holomorphic zeros. Consequently, we are able to obtain both lower and upper bounds on the supersymmetric mixing angles and predict the contributions to various flavor changing neutral current processes. We find that the most likely signals for alignment are $\Delta m_D$ close to the present bound, significant CP violation in $D^0-\bar{D^0}$ mixing, and shifts of order a few percent in various CP asymmetries in $B^0$ and $B_s$ decays. In contrast, the modifications to radiative B decays, to $\epsilon^\prime/\epsilon$ and to $K\to\pi\nu\bar\nu$ decays are small. We further investigate a new class of alignment models, where supersymmetric contributions to flavor changing processes are suppressed by both alignment and RGE-induced degeneracy.Comment: 20 pages, 3 figure

Influência dos teores de cálcio e de magnésio trocáveis, da capacidade de troca de cátions e do índice de saturação em bases sobre a fixação de zinco pelo solo

It was studied the effects of the exchangeabl e Ca2+ and Mg2+, the cation exchange capacities and the saturation Index in basis over the zinc fixation by 30 soil samples, using the 65zn as a tracer element. It was found positive and significative correlation at 1% among the Zn fixation and the mentioned variables. The results, however, are not conclusives and the authors keep the oppinion that more experiments must be done in order to elucidate the subject.Foram estudados os efeitos dos teores de Ca2+ e de Mg2+ trocáveis, das capacidades de troca de cátions e dos índices de saturação em bases de 30 amostras de terra sobre o poder de fixação de Zn das mesmas. Foram encontradas correlações positivas e significativas ao nível de 1% entre as capacidades de fixação de Zn das terras e as variáveis mencionadas

Nanoscale mapping of chemical composition in organic inorganic hybrid perovskite films

Lead-based organic-inorganic hybrid perovskite (OIHP) solar cells can attain efficiencies over 20%. However, the impact of ion mobility and/or organic depletion, structural changes, and segregation under operating conditions urge for decisive and more accurate investigations. Hence, the development of analytical tools for accessing the grain-to-grain OIHP chemistry is of great relevance. Here, we used synchrotron infrared nanospectroscopy (nano-FTIR) to map individual nanograins in OIHP films. Our results reveal a spatial heterogeneity of the vibrational activity associated to the nanoscale chemical diversity of isolated grains. It was possible to map the chemistry of individual grains in CsFAMA [Cs(0.05)FA(0.79)MA(0.16)Pb(I0.83Br0.17)(3)] and FAMA [FA(0.83)MA(0.17)Pb(I0.83Br0.17)(3)] films, with information on their local composition. Nanograins with stronger nano-FTIR activity in CsFAMA and FAMA films can be assigned to PbI2 and hexagonal polytype phases, respectively. The analysis herein can be extended to any OIHP films where organic cation depletion/accumulation can be used as a chemical label to study composition