A Study of Bull Associations

A cooperative bull association , according to the United States Department of Agriculture, is a farmers\u27 organlzation formed for the purpose of joint ownership, use, and exchange of high class, purebred dairy bulls. The members of the association are divided into three or more groups of neighboring farmers, each group being known as a block. A block may consist of one herd or several herds and contains from 40 to 60 cows. One bull is used in each block, and in order to prevent inbreeding, each bull is moved to another block every two years. If all the bulls live and are kept until each has made one complete circuit, no new bulls need to be purchased for six or more years, or as long as these bulls continue to be serviceable. During this time, each member will have had the use of a high class, purebred bull. A similar organization to this has been known in Europe for a number of years. The first bull association was started in the United States by the Michigan Agricultural College in 1908 and since that time the movement has spread throughout our whole country, and in 1925 the United States Department of Agriculture reported 220 associations containing 1003 bulls. Each association had an average of 31.1 members, 4.6 bulls, 40.9 purebred cows, and 157.7 grade cows. There was an average of 6.8 members and 43 cows per bull. Of the 39 states reporting associations at that time , Idaho ranked first wlth32 associations and Utah fifth, with 14. From the Summary of Bull Associations in United States, January 1, 1929, we find that there has been some increase over 1925. The report gives 339 active associations with 6353 members owning 1569 bulls. Texas, instead of Idaho, is now on lead with 57 associations and Utah is reported as having 18 associations with 77 bulls

Optical manifestations of topological Euler class in electronic materials

We analyze quantum-geometric bounds on optical weights in topological phases with pairs of bands hosting non-trivial Euler class, a multi-gap invariant characterizing non-Abelian band topology. We show how the bounds constrain the combined optical weights of the Euler bands at different dopings and further restrict the size of the adjacent band gaps. In this process, we also consider the associated interband contributions to DC conductivities in the flat-band limit. We physically validate these results by recasting the bound in terms of transition rates associated with the optical absorption of light, and demonstrate how the Euler connections and curvatures can be determined through the use of momentum and frequency-resolved optical measurements, allowing for a direct measurement of this multi-band invariant. Additionally, we prove that the bound holds beyond the degenerate limit of Euler bands, resulting in nodal topology captured by the patch Euler class. In this context, we deduce optical manifestations of Euler topology within $\vec{k} \cdot \vec{p}$ models, which include AC conductivity, and third-order jerk photoconductivities in doped Euler semimetals. We showcase our findings with numerical validation in lattice-regularized models that benchmark effective theories for real materials and are themselves directly realizable in metamaterials and optical lattices.Comment: 8+9 pages, 3 figure

Kinetic Characterization of Salmonella FliK-FlhB Interactions Demonstrates Complexity of the Type III Secretion Substrate-Specificity Switch

The bacterial flagellum is a complex macromolecular machine consisting of more than 20000 proteins, most of which must be exported from the cell via a dedicated Type III secretion apparatus. At a defined point in flagellar morphogenesis, hook completion is sensed and the apparatus switches substrate specificity type from rod and hook proteins to filament ones. How the switch works is a subject of intense interest. FIiK and F1hBs play central roles. In the present study, two optical biosensing methods were used to characterize FIiK-F1hB interactions using wild-type and two variant FlhBs from mutants with severe flagellar structural defects. Binding was found to be complex with fast and slow association and dissociation components. Surprisingly, wild-type and variant FlhBs had similar kinetic profiles and apparent affinities, which ranged between I and 10.5 μM, suggesting that the specificity switch is more complex than presently understood. Other binding experiments provided evidence for a conformational change after binding. Liquid chromatography-mass spectrometry (LC-MS) and NMR experiments were performed to identify a cyclic intermediate product whose existence supports the mechanism of autocatalytic cleavage at FlhB residue N269. The present results show that while autocatalytic cleavage is necessary for proper substrate specificity switching, it does not result in an altered interaction with FIiK. strongly suggesting the involvement of other proteins in the mechanism

Extensions of tempered representations

Let $\pi, \pi'$ be irreducible tempered representations of an affine Hecke algebra H with positive parameters. We compute the higher extension groups $Ext_H^n (\pi,\pi')$ explicitly in terms of the representations of analytic R-groups corresponding to $\pi$ and $\pi'$. The result has immediate applications to the computation of the Euler-Poincar\'e pairing $EP(\pi,\pi')$, the alternating sum of the dimensions of the Ext-groups. The resulting formula for $EP(\pi,\pi')$ is equal to Arthur's formula for the elliptic pairing of tempered characters in the setting of reductive p-adic groups. Our proof applies equally well to affine Hecke algebras and to reductive groups over non-archimedean local fields of arbitrary characteristic. This sheds new light on the formula of Arthur and gives a new proof of Kazhdan's orthogonality conjecture for the Euler-Poincar\'e pairing of admissible characters.Comment: This paper grew out of "A formula of Arthur and affine Hecke algebras" (arXiv:1011.0679). In the second version some minor points were improve

Advertising, product quality, and complex evolving marketing systems

The paper analyses the advertising as power vs. advertising as information controversy as well as its recent empirical testing. It is stressed that this distinction focuses too much on the interaction between consumer and manufacturer while ignoring the retailer as an important stake-holder. To compensate for this lack, a complex marketing system perspective is introduced in which consumer, retailer, and manufacturer interact. However, these complex marketing systems might drift towards market equilibria which are against the consumer interests: that is, firmsmight lock out brands from the market by means of trade and sales promotions and then use advertising to protect their position. Consequently brands of better quality and/or innovative brands are barred from trade shelves

Genetic mixed stock analysis of an interceptory Atlantic salmonfishery in the Northwest Atlantic

Interceptory fisheries represent an ongoing threat to migratory fish stocks particularly when managed in the absence of stock specific catch and exploitation information. Atlantic salmon from the southern portion of the North American range may be subject to exploitation in the commercial and recreational salmon fisheries occurring in the French territorial waters surrounding St. Pierre and Miquelon off southern Newfoundland. We evaluated stock composition of Atlantic salmon harvested in the St. Pierreand Miquelon Atlantic salmon fishery using genetic mixture analysis and individual assignment with a microsatellite baseline (15 loci, 12,409 individuals, 12 regional groups) encompassing the species western Atlantic range. Individual salmon were sampled from the St. Pierre and Miquelon fishery over four years (2004, 2011, 2013, and 2014). Biological characteristics indicate significant variation among years in the size and age distribution. Nonetheless, estimates of stock composition of the samples showed consistent dominance of three regions (i.e., Southern Gulf of St. Lawrence, Gaspe Peninsula, and New-foundland). Together salmon from these regions accounted for more than 70% of annual harvest over the decade examined. Comparison of individual assignments and biological characteristics revealed a trend of declining fresh water age with latitude of assigned region. Moreover, locally harvested Newfoundland salmon were ten times more likely to be small or one sea winter individuals whereas Quebec and Gaspe Peninsula salmon were two-three times more likely to be harvested as large or two sea winter salmon.Estimates of region specific catch were highest for salmon from the southern Gulf of St. Lawrence region ranging from 242 to 887 individuals annually. This work illustrates how genetic analysis of interceptory marine fisheries can directly inform assessment and management efforts in highly migratory marines pecies

The Kinase Function of MSK1 Regulates BDNF Signaling to CREB and Basal Synaptic Transmission, But Is Not Required for Hippocampal Long-Term Potentiation or Spatial Memory

The later stages of long-term potentiation (LTP) in vitro and spatial memory in vivo are believed to depend upon gene transcription. Accordingly, considerable attempts have been made to identify both the mechanisms by which transcription is regulated and indeed the gene products themselves. Previous studies have shown that deletion of one regulator of transcription, the mitogen- and stress-activated kinase 1 (MSK1), causes an impairment of spatial memory. Given the ability of MSK1 to regulate gene expression via the phosphorylation of cAMP response element binding protein (CREB) at serine 133 (S133), MSK1 is a plausible candidate as a prime regulator of transcription underpinning synaptic plasticity and learning and memory. Indeed, prior work has revealed the necessity for MSK1 in homeostatic and experience-dependent synaptic plasticity. However, using a knock-in kinase-dead mouse mutant of MSK1, the current study demonstrates that, while the kinase function of MSK1 is important in regulating the phosphorylation of CREB at S133 and basal synaptic transmission in hippocampal area CA1, it is not required for metabotropic glutamate receptor-dependent long-term depression (mGluR-LTD), two forms of LTP or several forms of spatial learning in the watermaze. These data indicate that other functions of MSK1, such as a structural role for the whole enzyme, may explain previous observations of a role for MSK1 in learning and memory

Towards a framework for critical citizenship education

Increasingly countries around the world are promoting forms of "critical" citizenship in the planned curricula of schools. However, the intended meaning behind this term varies markedly and can range from a set of creative and technical skills under the label "critical thinking" to a desire to encourage engagement, action and political emancipation, often labelled "critical pedagogy". This paper distinguishes these manifestations of the "critical" and, based on an analysis of the prevailing models of critical pedagogy and citizenship education, develops a conceptual framework for analysing and comparing the nature of critical citizenship