Albert Fert

Albert Fert va néixer a Carcassona l'any 1938. Membre de l'Acadèmia Francesa de les Ciències, és professor de Física a la Universitat de París Sud des de l'any 1975. Entre els anys 1970 i 1975 va ser director de recerca al Laboratoire de Physique des Solides (Université Paris-Surd, Orsay) i, des del 1995 és director científic de la Unité Mixte de Physique CNRS/Thales (Palaiseau). L'activitat científica d'Albert Fert s'ha centrat en treballs experimentals i teòrics en el camp de la Física de la Matèria Condensada (metalls i aliatges, magnetisme, vidres d'espí, transport electrònic, nanostructures magnètiques i electrònica d'espí). Ha fet contribucions pioneres, fonamentalment relacionades amb el transport de càrrega depenent de l'espí que, finalment, el van portar a descobrir la GMR i a fer de l'espintrònica un nou camp de la ciència que pot rellevar l'electrònica actual. Fert va descobrir la GMR al mateix temps, encara que de manera independent, que el científic Peter Grunberg. Tots dos van rebre el Premi Nobel de Física 2007 per aquesta troballa, que es pot considerar la primera aplicació a gran escala de les noves nanotecnologies. Aquest efecte és la base de l'espintrònica, que explota la càrrega de l'electró i l'orientació de l'espí, o imant, per obtenir dispositius més petits i eficaços, i permet que puguin tenir noves funcionalitats. L'investigador francès ha publicat prop de 300 articles i ha col·laborat en 7 llibres. S'han fet més d'11.000 citacions dels seus articles. A més del Premi Nobel, ha rebut diversos guardons nacionals i internacionals, entre les quals cal remarcar el premi internacional James C. McGroddy Prize for New Materials de la Societat Americana de Física i el premi Europhysics de la Societat Europea de Física. Albert Fert col·labora estretament amb diferents centres de recerca i laboratoris del campus de la UAB, especialment amb l'ICMAB, que forma part del Parc de Recerca UAB. Ha estat vinculat també amb altres institucions científiques i universitàries catalanes, destacant la seva col·laboració activa en la creació de l'Institut Català de Nanotecnologia, centre del Parc de Recerca UAB, pel que fa a les línies de recerca que s'hi desenvolupenNomenament 21/05/2009. A proposta de Facultat de Ciències. Investidura 21/05/2009. Padrí: Josep Fontcubert

Genetic merit for fertility traits in Holstein cows: VI. Oocyte developmental competence and embryo development

peer-reviewedThe hypothesis of this study was that cows with good genetic merit for fertility traits (Fert+) would produce oocytes and embryos of greater quality than cows with poor genetic merit for fertility traits (Fert−) and that mRNA expression of candidate genes would reflect the observed differences in quality. The aim of the study, therefore, was to determine the effect of genetic merit for fertility traits on morphological classification and mRNA abundance of key genes in immature oocytes and cumulus cells following ovum pick-up and in embryos following superovulation, artificial insemination (AI), and uterine flushing. In experiment 1, 17 Fert+ and 11 Fert− cows, ranging from 54 to 84 d in milk, were submitted to ovum pick-up on 4 occasions during a 2-wk period. Recovered cumulus–oocyte complexes (COC) were morphologically graded. Oocytes and cumulus cells were separated, and mRNA abundance of genes associated with oocyte developmental competence was measured. There was no effect of genotype on the distribution of COC grades or on the mRNA abundance of the candidate genes in grade 1 COC. In experiment 2, 20 Fert+ and 19 Fert− cows, ranging from 71 to 189 d in milk, were submitted to superovulation and AI. The uteri of cows that responded to the superovulation protocol (17 Fert+ and 16 Fert− cows) were nonsurgically flushed 7 d postovulation. Recovered embryos were morphologically graded, and mRNA abundance of genes associated with embryo development was measured in grade 1 blastocysts. The response to the superovulation protocol was assessed by counting the number of codominant follicles on the day of AI, which was similar for both genotypes (22.0 ± 9.7 and 19.8 ± 8.2 for Fert+ and Fert− cows, respectively). There was no effect of genotype on the proportion of transferable embryos recovered or on the mRNA abundance of the candidate genes tested in the grade 1 blastocysts. Of the total embryos classified as blastocysts, however, the Fert+ cows tended to have a greater proportion of grade 1 blastocysts compared with Fert− cows (90% vs. 64%, respectively). In conclusion, genetic merit for fertility traits had a no effect on mRNA abundance of the candidate genes that were examined in immature oocytes and cumulus cells and in embryos recovered after superovulation. The observed differences in morphological blastocyst quality following superovulation would suggest that the superior reproductive performance of Fert+ cows could arise during the later stages of embryo development from d 7 until maternal recognition of pregnancy

Flow control of agricultural spraying machines : a thesis in partial fulfilment of the requirements for the degree of Master of Engineering in Mechatronics, Massey University, Palmerston North, New Zealand

New Zealand relies heavily on its agricultural industry. A large portion of this industry is pastoral farming, where livestock are raised to graze on pasture. This includes beef, sheep and dairy farming. An important aspect of this style of farming is maintaining pasture quality. In order to increase growth fertilisers are often applied to the pastures. This increases yields in both meat and milk production. However, the increased application of fertiliser is linked with diminishing water quality. While the effects of nitrogen leaching and the best ways to manage fertiliser use are still being investigated, it is clear that control over the application will become more and more important. The Tow and Fert is a range of fertiliser machines designed and built in New Zealand by Metalform Dannevirke. The Tow and Fert range is capable of spraying a wide range of fertilisers including both soluble and non-soluble fertilisers. The Tow and Fert is unique in its ability to spray fertiliser slurries consisting of mixture ratios of up to three-parts fine particle fertiliser to one-part water. This is achieved by the use of a recirculating system. Currently there is next to no control on the flow rate of the machines and the application rate is determined by the speed the operator maintains. The purpose of this thesis is to design and build a flow control system for the Tow and Fert product range and investigate the effect of the changing flow rate on the spray characteristics. The ability to spray such a wide range of fluids with drastically different properties presents many challenges. Many flow meters were considered and a low cost ultrasonic sensor (TUF2000M) was installed and investigated. After limited success of the ultrasonic sensor, a simple turbine flowmeter was installed. A flow controller was developed and tuned. Based off a PID control loop, the controller was able to maintain flowrate well between 10 L/min and 25 L/min depending on the installed nozzle. After flow control had been achieved, methods for assessing the impact of flow rate on spray characteristics and specifically spray distribution were investigated. Several prototypes were created and tested. A stationary patternator capable of continuous measurement was developed and tested. The patternator does not correctly measure the flowrates in low flow sections. Only half of the flow being applied to the platform is being measured. This causes highly nonlinear results in spray distribution measurement. The testing did show an increase of spray area with increasing flowrate. However, the true distribution can be improved when the low flow issues have been resolved

Applicability of single-step genomic evaluation with a random regression model for reproductive traits in turkeys (Meleagris gallopavo).

Fertility and hatchability are economically important traits due to their effect on poult output coming from the turkey hatchery. Traditionally, fertility is recorded as the number of fertile eggs set in the incubator (FERT), defined at a time point during incubation by the identification of a developing embryo. Hatchability is recorded as either the number of fertile eggs that hatched (hatch of fertile, HOF) or the number hatched from all the eggs set (hatch of set, HOS). These traits are collected throughout the productive life of the bird and are conventionally cumulated, resulting in each bird having a single record per trait. Genetic evaluations of these traits have been estimated using pedigree relationships. However, the longitudinal nature of the traits and the availability of genomic information have renewed interest in using random regression (RR) to capture the differences in repeatedly recorded traits, as well as in the incorporation of genomic relationships. Therefore, the objectives of this study were: 1) to compare the applicability of a RR model with a cumulative model (CUM) using both pedigree and genomic information for genetic evaluation of FERT, HOF, and HOS and 2) to estimate and compare predictability from the models. For this study, a total of 63,935 biweekly FERT, HOF, and HOS records from 7,211 hens mated to 1,524 toms were available for a maternal turkey line. In total, 4,832 animals had genotypic records, and pedigree information on 11,191 animals was available. Estimated heritability from the CUM model using pedigree information was 0.11 0.02, 0.24 0.02, and 0.24 0.02 for FERT, HOF, and HOS, respectively. With random regression using pedigree relationships, heritability estimates were in the range of 0.04-0.09, 0.11-0.17, and 0.09-0.18 for FERT, HOF, and HOS, respectively. The incorporation of genomic information increased the heritability by an average of 28 and 23% for CUM and RR models, respectively. In addition, the incorporation of genomic information caused predictability to increase by approximately 11 and 7% for HOF and HOS, respectively; however, a decrease in predictability of about 12% was observed for FERT. Our findings suggest that RR models using pedigree and genomic relationships simultaneously will achieve a higher predictability than the traditional CUM model

Nitrogen Input Effects on Herbage Accumulation and Presence of Pasture Plant Species

Long-term responses of pasture plant species to management strategies that vary amount and form of N inputs form a knowledge gap. Our objective was to determine how supplementation of grazing beef cattle (Bos taurus) with corn (Zea mays L.) dried distillers grains plus solubles (DDGS) in unfertilized pasture (SUPP) affects annual herbage accumulation and presence of plant species and functional groups relative to unsupplemented beef cattle on unfertilized (CONT) and N-fertilized (FERT) smooth bromegrass (Bromus inermis Leyss.) pasture. We addressed this objective in the sixth (2010) and seventh (2011) years of a long-term experiment in eastern Nebraska, where N input from DDGS supplementation and urea fertilizer averaged 0, 43, and 90 kg ha–1 yr–1 within CONT, SUPP, and FERT, respectively. For these years, annual herbage accumulation averaged 6.87, 6.80, and 10.58 Mg ha–1 (LSD = 1.49) and 66.5, 66.2, and 76.0% of herbage accumulated by 25 June (LSD = 5.3) in CONT, SUPP, and FERT, respectively. Smooth bromegrass occurred in 99.8% of 0.1-m2 pasture quadrats regardless of treatment. Cessation of N fertilizer input, however, increased presence of annual foxtail (Setaria spp.), annual graminoids, and annuals among quadrats in CONT relative to FERT. Supplementation of DDGS, while shown in previous studies to improve weight gains and N use efficiency in cattle, supplied enough N through excretion to provide an intermediate level of resistance to annual weeds. Nitrogen excreted from cattle supplemented with DDGS, however, did not aff ect herbage accumulation in subsequent years

Synchronization of spin-transfer oscillators driven by stimulated microwave currents

We have simulated the non-linear dynamics of networks of spin-transfer oscillators. The oscillators are magnetically uncoupled but electrically connected in series. We use a modified Landau-Lifschitz- Gilbert equation to describe the motion of each oscillator in the presence of the oscillations of all the others. We show that the oscillators of the network can be synchronized not only in frequency but also in phase. The coupling is due to the microwave components of the current induced in each oscillator by the oscillations in all the other oscillators. Our results show how the emitted microwave power of spin-transfer oscillators can be considerably enhanced by current-induced synchronization in an electrically connected network. We also discuss the possible application of our synchronization mechanism to the interpretation of the surprisingly narrow microwave spectrum in some isolated spin-transfer oscillators