Milk progesterone as a tool to improve fertility in dairy cows

Milk progesterone offers an opportunity to objectively study fertility in dairy cows, in contrast to traditional measures of dairy cow fertility, which in general are highly influenced by on-farm management decisions. The aim of this thesis was to study how milk progesterone could be used as a genetic and management tool to improve fertility in dairy cows. Progesterone-based measures were influenced by different systematic factors, e.g. breed, parity, season, housing and lameness, studied in a dataset from a Swedish experimental herd. The repeatabilities were higher for progesterone-based measures compared with traditional measures of fertility based on insemination data. If a cow had an atypical progesterone profile in one lactation, the risk of an atypical profile in the next lactation was increased. Genetic parameters for progesterone measures based on different milk sampling intervals were estimated in a British dataset. Heritability estimates were moderate, but decreased with increased sampling intervals. It was shown that progesterone analysis of monthly milk samples, resembling milk sampling as in the current Swedish milk recording system, could be used to increase the accuracy of genetic evaluation for an earlier start of cyclical ovarian activity after calving. Inclusion of monthly milk sampling for progesterone analysis in predictive models could also be used to identify cows with delayed ovarian cyclicity with a high accuracy already two months after calving. This enables an earlier treatment of ovarian dysfunction and therefore, probably, a shorter calving interval. In conclusion, this thesis shows that milk progesterone may be used for improved management and genetic evaluation of dairy cow fertility

Wide-bandwidth mode-hop-free tuning of extended-cavity GaN diode lasers

We present a new approach for extended-cavity diode-laser tuning to achieve wide mode-hop-free tuning ranges. By using a multiple piezoactuated grating mount, the cavity length and grating angle in the laser can be adjusted independently, allowing mode-hop-free tuning without the need for a mechanically optimized pivot-point mount. Furthermore, synchronized diode injection-current tuning allows diode lasers without antireflection coatings to be employed. In combination these two techniques make the construction of a cheap, efficient, and easily optimized extended-cavity diode laser possible. A theoretical analysis is presented for optimal control of piezoactuator displacements and injection current to achieve the widest possible mode-hop-free tuning ranges, and a comparison is made with measurements. The scheme is demonstrated for blue and violet GaN lasers operating at similar to 450 nm and similar to 410 nm, for which continuous tuning ranges exceeding 90 GHz have been achieved. Examples of applications of these lasers are also given

Fundamental bounds on transmission through periodically perforated metal screens with experimental validation

This paper presents a study of transmission through arrays of periodic sub-wavelength apertures. Fundamental limitations for this phenomenon are formulated as a sum rule, relating the transmission coefficient over a bandwidth to the static polarizability. The sum rule is rigorously derived for arbitrary periodic apertures in thin screens. By this sum rule we establish a physical bound on the transmission bandwidth which is verified numerically for a number of aperture array designs. We utilize the sum rule to design and optimize sub-wavelength frequency selective surfaces with a bandwidth close to the physically attainable. Finally, we verify the sum rule and simulations by measurements of an array of horseshoe-shaped slots milled in aluminum foil.Comment: 10 pages, 11 figures. Updated Introduction and Conclusion

Sur la symétrie présumée entre valeurs et préférences

Comment pouvons-nous analyser des relations de valeur non standards, comme la parité axiologique, en termes d’attitudes appropriées? Wlodek Rabinowicz suggère que deux choses sont à parité si et seulement si il est à la fois permissible de préférer l’une à l’autre et permissible d’avoir la préférence contraire. Dans un article récent, Johan Gustafsson soutient toutefois que l’analyse de Rabinowicz viole un principe de symétrie entre valeurs et préférences, selon lequel il existe pour toute relation de valeur une relation de préférence correspondante (et vice-versa). À la lumière de ce principe, Gustafsson propose une analyse alternative, selon laquelle deux choses sont à parité si et seulement si il est requis d’entretenir ces choses en parité préférentielle. Dans cet article, j’examine en détail les arguments avancés par Gustafsson contre l’analyse de Rabinowicz et je montre qu’aucun d’eux n’est convaincant

IAU Symposium 241 - Stellar Populations as Building Blocks of Galaxies

Stellar populations, building blocks of galaxies, are direct tracers of the star formation history, the chemical enrichment and the assembly of galaxies in the Universe. They therfore allow us to understand how galaxies formed and evolved. This last decade has witnessed a revolution in our observations of galaxies; with larger telescopes and new instruments we are not only able to look deeper in the Universe, we can also study nearby galaxies with greater detail. The fact that now is becoming possible to resolve stars up to the distance of Virgo Cluster allows us to rigorously compare and calibrate the analysis of the integrated light with resolved stellar populations. These Proceedings report the considerable progress made in recent years in this topic. Theorists and observers, researchers of resolved and unresolved stellar populations, discussed the ingredients of stellar population models, and rigorously compared them to new data, forcing theorists to develop more refined models and methods to derive the physical parameters of the stellar populations. New results from the Milky Way, the Local Group, and nearby and distant galaxies were presented.Comment: This is the table of contents of the upcoming proceedings of IAU Symposium 241. The book will appear in September, from Cambridge University Press, and will also be available electronically at http://www.journals.cambridge.org/action/displayJournal?jid=IA

Legal Statutes of Arab Refugees

The recently developed particle filter offers a general numerical tool to approximate the state a posteriori density in nonlinear and non-Gaussian filtering problems with arbitrary accuracy. Because the particle filter is fairly easy to implement and tune, it has quickly become a popular tool in signal processing applications. Its main drawback is that it is quite computer intensive. For a given filtering accuracy, the computational complexity increases quickly with the state dimension. One remedy to this problem is what in statistics is called Rao-Blackwellization, where states appearing linearly in the dynamics are marginalized out. This leads to that a Kalman filter is attached to each particle. Our main contribution here is to sort out when marginalization is possible for state space models, and to point out the implications in some typical signal processing applications. The methodology and impact in practice is illustrated on terrain navigation for aircrafts. The marginalized particle filter for a state-space model with nine states is evaluated on real aircraft data, and the result is that very good accuracy is achieved with quite reasonable complexity

The Levelling-Down Objection and the Additive Measure of the Badness of Inequality

The Levelling-Down Objection is a standard objection to monistic egalitarian theories where equality is the only thing that has intrinsic value. Most egalitarians, however, are value pluralists; they hold that, in addition to equality being intrinsically valuable, the egalitarian currency in which we are equal or unequal is also intrinsically valuable. In this paper, I shall argue that the Levelling-Down Objection still minimizes the weight that the intrinsic badness of inequality could have in the overall intrinsic evaluation of outcomes, given a certain way of measuring the badness of inequality, namely, the Additive Individual-Complaints Measure

Augustana Seniors Fall 1884: Johan Wilhelm Nyvall

Johan (John) Wilhelm Nyvall was a senior at Augustana College, Rock Island, Illinois, in the fall of 1884. His name appears in the college catalog of 1884 – 1885, along with his birthplace, the year of his birth, and a few other facts. From this start, we researched the genealogy and family history of J.W. Nyvall. This paper contains a short biography of Nyvall, a report on his ancestors, a report on his descendants, and some open questions for further research

Utilization of single-cell RNA-Seq and genome-scale modeling for investigating cancer metabolism

Cancer remains a leading cause of death worldwide, and its dysregulated metabolism is a promising target for therapy. However, metabolism is complex to study – the metabolism of a cell involves the interplay of thousands of chemical reactions that are combined in different ways across tissues and cell types. Genome-scale metabolic models (GEMs), where the reaction networks of cells are described using a mathematical formulation, have been developed to help in such studies. In this thesis, methods were developed for determining the active metabolic network (the context-specific model) in individual cell types, followed by studies of cancer metabolism. To enable identification of the active metabolic network per cell type, single-cell RNA sequencing (scRNA-Seq) was employed to detect the presence of individual genes. However, the technical and biological variation in scRNA-Seq data poses a major challenge to the identification of the active reaction network in a cell type. The variability of gene expression due to technical and biological factors was therefore examined, concluding that data from thousands of cells is often required to provide enough stability for robust model generation. An improved quantification method for scRNA-Seq data, called BUTTERFLY, was also developed and implemented as part of the kallisto-bustools scRNA-Seq workflow. A new optimized version of tINIT, which enables generation of context-specific models, was also developed. It allowed for generation of models based on bootstrapped cell populations, which were used to acquire the statistical uncertainty of models generated from scRNA-Seq data. Finally, the method was applied to a lung cancer dataset, identifying both known and unknown features of cancer metabolism.To further explore cancer metabolism, a study was conducted to investigate the most optimal metabolic behavior under different degrees of hypoxia. To this end, a diffusion-based model for estimating nutrient availability was developed, as well as a light-weight version of the tool GECKO that enables constraining the total enzyme usage in the model. The model could explain the glutamine addiction phenomenon in cancers and was used to show that metabolic collaboration between cell types in tumors is likely not important for growth