Stiffer optical tweezers through real-time feedback control

Using real-time re-programmable signal processing we connect acousto-optic steering and back-focal-plane interferometric position detection in optical tweezers to create a fast feedback controlled instrument. When trapping 3 µm latex beads in water we find that proportional-gain position-clamping increases the effective lateral trap stiffness ~13-fold. A theoretical power spectrum for bead fluctuations during position-clamped trapping is derived and agrees with the experimental data. The loop delay, ~19 µs in our experiment, limits the maximum achievable effective trap stiffness

Genetic variances, trends and mode of inheritance for hip and elbow dysplasia in Finnish dog populations

The aims of this study were to assess genetic variances, trends and mode of inheritance for hip and elbow dysplasia in Finnish dog populations. The influence of time-dependent fixed effects in the model when estimating the genetic trends was also studied. Official hip and elbow dysplasia screening records of 42 421 dogs from seven breeds were analysed with REML. To investigate the mode of inheritance of hip and elbow dysplasia, trait distributions, genetic variances and regressions of offspring phenotypes on parental predicted breeding values were studied separately in males and in females. Genetic trends for hip dysplasia between the years 1983 and 1998 were favourable only in the Rottweiler. In elbow dysplasia, the trends were favourable after the year 1992 in all the four breeds studied but the overall changes were small. The reason for this seemed to be negligible selection pressure against these traits. Time-dependent fixed effects in the model had an influence on the estimated genetic trends, resulting either in a more negative or more positive genetic trend compared with the model from which the time-dependent effects were removed. Mitochondrial or sex-linked inheritance did not seem likely in the expression of hip and elbow dysplasia in the populations studied. Regression coefficients of offspring phenotypes on estimated parental breeding values were approximately equal to their expected value in a situation with equal parental contribution. Furthermore, the phenotypic frequency distributions of hip and elbow dysplasia grades were similar among males and females in each breed studied. No indication of major genes was found in the offspring frequency distributions within individual sires. According to these Finnish data, mode of inheritance for both hip and elbow dysplasia is polygenic (quantitative) with equal expression of the genes from both parents, although the estimates of heritability for hip dysplasia in the Rough Collie and for elbow dysplasia in the German Shepherd and the Golden Retriever were somewhat different in males compared with females

Catalytic abatement of trichloroethylene over Mo and/or W-based bronzes

[EN] In this paper we present the results of the synthesis, characterization and catalytic behaviour of Mo(W)¿Nb¿V¿O mixed metal oxides bronzes for the catalytic oxidation of trichloroethylene. The catalysts were prepared hydrothermally with different Mo/W/Nb/V/P atomic ratio and heat-treated at 500 and 700 °C. They were characterized by several techniques as N2-adsorption, X-ray diffraction, FTIR, SEM-EDS, temperature programmed desorption, temperature programmed reduction, UV¿vis, Fourier transformed infrared spectroscopy of adsorbed pyridine and 18O/16O isotope exchange. X-ray diffraction patterns (XRD) of samples heat-treated at 500 °C suggest the presence of a semi-crystalline material with a diffraction peak at ca. 2¿ = 22.2°, while XRD patterns of samples heat-treated at 700 °C show the formation of a tetragonal tungsten bronze (TTB) structure. The activity for the catalytic abatement of trichloroethylene strongly depends on the heat-treatment temperature and the catalyst composition. Thus, samples with W/(Mo + W) atomic ratios of 0.25-0.75 and heat-treated at 500 °C are the most active ones. The enhanced activity has been related to the remarkable higher surface area of the catalyst and to the catalyst composition which influences the acid characteristics as well as the reducibility and reoxidation of the catalysts. The importance of the oxygen dissociation on the catalyst surface and the diffusion of oxygen species through the catalyst are also discussed.The authors wish to thank DGICYT in Spain (Project CTQ2009-14495 and CSD2009-00050-CONSOLIDER/INGENIO 2010) and Universitat Politecnica de Valencia for the financial support. N.B.R. acknowledges Catedra Cemex Sostenibilidad (UPV) for a fellowship. M.D.S. acknowledges Universitat Politecnica de Valencia for a fellowship.Blanch Raga, N.; Soriano Rodríguez, MD.; Palomares Gimeno, AE.; Concepción Heydorn, P.; Martínez Triguero, LJ.; López Nieto, JM. (2013). Catalytic abatement of trichloroethylene over Mo and/or W-based bronzes. Applied Catalysis B: Environmental. 130-131:36-43. https://doi.org/10.1016/j.apcatb.2012.10.016S3643130-13

Relationships of body weight and carcass quality traits with first lactation milk production in Finnish Ayrshire cows

Relationships of body weight and carcass quality traits with first lactation milk production traits were estimated from a field data set of 28362 Finnish Ayrshire cows, using REML methodology and animal model. Studied body weight traits included heifer and mature live weight, estimated based on heart girth circumference as part of normal milk recording system, and carcass weight recorded in the slaughterhouse. Additional carcass quality measures included carcass fleshiness and fatness as recorded in the slaughterhouse. Milk production traits included first lactation 305-d milk, fat and protein yield, and fat and protein percentage. Genetic correlations between carcass weight and yield traits were almost zero, while the genetic correlations between live weight and yield traits were of somewhat higher magnitude. This suggests a negative correlation between yield traits and killing out percentage, which might be caused by a difference in the digestive tract weight and feed intake capacity. The genetic correlations between carcass quality and yield traits were negative and low to moderate. Selection for high yield alone seems thus to lead into reduction in body condition, which in turn might lead into more negative energy balance especially in early lactation

Relationships of body weight and carcass quality traits with first lactation milk production in Finnish Ayrshire cows

Relationships of body weight and carcass quality traits with first lactation milk production traits were estimated from a field data set of 28362 Finnish Ayrshire cows, using REML methodology and animal model. Studied body weight traits included heifer and mature live weight, estimated based on heart girth circumference as part of normal milk recording system, and carcass weight recorded in the slaughterhouse. Additional carcass quality measures included carcass fleshiness and fatness as recorded in the slaughterhouse. Milk production traits included first lactation 305-d milk, fat and protein yield, and fat and protein percentage. Genetic correlations between carcass weight and yield traits were almost zero, while the genetic correlations between live weight and yield traits were of somewhat higher magnitude. This suggests a negative correlation between yield traits and killing out percentage, which might be caused by a difference in the digestive tract weight and feed intake capacity. The genetic correlations between carcass quality and yield traits were negative and low to moderate. Selection for high yield alone seems thus to lead into reduction in body condition, which in turn might lead into more negative energy balance especially in early lactation

An indication of major genes affecting hip and elbow dysplasia in four Finnish dog populations

The aim of the study was to assess the possible existence of major genes influencing hip and elbow dysplasia in four dog populations. A Bayesian segregation analysis was performed separately on each population. In total, 34 140 dogs were included in the data set. Data were analysed with both a polygenic and a mixed inheritance model. Polygenic models included fixed and random environmental effects and additive genetic effects. To apply mixed inheritance models, the effect of a major gene was added to the polygenic models. The major gene was modelled as an autosomal biallelic locus with Mendelian transmission probabilities. Gibbs sampling and a Monte Carlo Markov Chain algorithm were used. The goodness-of-fit of the different models were compared using the residual sum-of-squares. The existence of a major gene was considered likely for hip dysplasia in all the breeds and for elbow dysplasia in one breed. Several procedures were followed to exclude the possible false detection of major genes based on non-normality of data: permuted datasets were analysed, data-transformations were applied, and residuals were judged for normality. Allelic effects at the major gene locus showed nearly to complete dominance, with a recessive, unfavourable allele in both traits. Relatively high estimates of the frequencies of unfavourable alleles in each breed suggest that considerable genetic progress would be possible by selection against major genes. However, the major genes that are possibly affecting hip and elbow dysplasia in these populations will require further study

The effect of breeding schemes on the genetic response of canine hip dysplasia, elbow dysplasia, appearance and behaviour traits

Current dog breeding programmes must be changed if genetic improvement in health and behaviour traits is to be achieved. A computer simulation programme was used to assess the possible genetic improvement in hip dysplasia (HD), elbow dysplasia (ED) and behaviour (BE) traits in a dog population whilst simultaneously selecting for appearance (AP). The structure of the Finnish Rottweiler population was used in the simulation. Over a ten-year period (1989-1998), the realised genetic response to selection in the Finnish Rottweiler population was 0.03 genetic standard deviations (SD) for both HD and ED. The relative selection index weights were iterated in the simulation, accordingly, as 0.4 for both traits. In the current breeding strategies, AP dominates other traits. Present index weights for BE and AP were therefore assumed to be 0.5 and 2.0, respectively. With these assumed current index weights, using best linear unbiased prediction (BLUP) breeding values, neither an increase in the number of breeding candidates nor an increase in the number of screened relatives of the candidates resulted in further genetic response for HD, ED or BE. The desired genetic responses for HD, ED and BE over a period of 10 years could only be attained by changing the relative selection index weights dramatically in favour of these traits. As long as the index weights clearly favoured HD, ED and BE, the increase in the number of breeding candidates, ie in the number of screened dogs, resulted in a further response in these traits. To preserve desired behaviour and to improve health in dog breeds, systematic breeding programmes favouring these traits should be developed, and a greater number of dogs should be screened for health and behaviour. Breeders should stop breeding exhaustively for appearance and place more emphasis on health and behaviour traits