The Value of Information in Salmon Farming: Harvesting the Right Fish to the Right Time

Research regarding management practice in fish farming has traditionally focused on two topics: production planning and forecasting of prices. This article combine these two areas of research, and illustrate how information of price patterns can change production plans, and hence increase the value of the farm enterprise. We present a model farm and illustrate with different levels of price information how information of future prices alter the original production plan and hence create extra value for the farmer. The phrasing of the paper and the empirical application are on salmon and salmon farming, but the ideas and general results should be applicable to all farmed species.Resource /Energy Economics and Policy,

System development of the Screwworm Eradication Data System (SEDS) algorithm

The use of remotely sensed data is reported in the eradication of the screwworm and in the study of the role of the weather in the activity and development of the screwworm fly. As a result, the Screwworm Eradication Data System (SEDS) algorithm was developed

Interaction between gravitational waves and plasma waves in the Vlasov description

The nonlinear interaction between electromagnetic, electrostatic and gravitational waves in a Vlasov plasma is reconsidered. By using a orthonormal tetrad description the three-wave coupling coefficients are computed. Comparing with previous results, it is found that the present theory leads to algebraic expression that are much reduced, as compared to those computed using a coordinate frame formalism. Furthermore, here we calculate the back-reaction on the gravitational waves, and a simple energy conservation law is deduced in the limit of a cold plasma.Comment: 9 pages, uses jpp.cl

Motivational Interviewing in an ordinary clinical setting: A controlled clinical trial at the Swedish National Tobacco Quitline

AbstractIntroductionThe present study aimed to assess the effect of adding Motivational Interviewing (MI) to the first session of an effective smoking cessation treatment protocol in an ordinary clinical setting: the Swedish National Tobacco Quitline (SNTQ).MethodThe study was designed as a controlled clinical trial. Between September 2005 and October 2006, 772 clients accepted the invitation to participate in the study and were semi-randomised to either standard treatment (ST) or MI. The primary outcome measures were self-reported 7-day point prevalence abstinence and 6-month continuous abstinence.ResultsAt 12-month follow-up, the 772 clients were included in an intention to treat analysis. Of the clients allocated to MI, 57/296 (19%) reported 6-month continuous abstinence compared to 66/476 (14%) of the clients allocated to ST (OR 1.48, 95% CI 1.00–2.19; P=.047).ConclusionsIntegrating MI into a cognitive behavioural therapy-based smoking cessation counselling in an ordinary clinical setting at a tobacco quitline increased client 6-month continuous abstinence rates by 5%

A survey of dystocia in the Boxer breed

BACKGROUND: Dystocia occurs more commonly in some breeds of dogs than others. The Boxer breed is one of the highrisk breeds for whelping problems. The aim of this study was to document some reproductive parameters and the frequency of dystocia in Boxers. METHODS: Two questionnaires were sent to the breeders of Boxers in Sweden during 1994 to 1997. Data from 253 whelpings and 1671 pups was received, which constitutes 56.5% of all Boxer litters registered with the Swedish Kennel Club during these years. Data was analysed using Chi-square test, and Fischer's exact test. RESULTS: Dystocia occurred in 32% of the individual bitches, and in 27.7% of all the whelpings. Caesarian section was performed in 22.8% of all the whelpings and in 80.1% of the cases of dystocia. Medical treatment was tried in 20 cases but was successful only in 5 (25%). The dystocia was of maternal origin in 68.6% and of fetal origin in 28.6% of cases. The most common reasons for dystocia were primary uterine inertia (60%) and malpresentation of the fetus (26%). Dystocia increased with increasing age of the bitch from four years of age. Average litter size was 6.6 (± 2.2) pups born, and 5.0 (± 2.1) pups registered. Pup mortality was 24%. Stillbirths accounted for 6.1% of the pup deaths and 1% died in the neonatal period, while 15.6% of the pups were euthanised, the majority because they had disqualifying white coat colour. Cryptorchidism was observed in 9.8% of the male pups born and in 13.4% of the male pups that were registered. CONCLUSION: The Boxer suffers a high frequency of dystocia, mainly due to uterine inertia, but also fetal malpresentation. Breeders should be adviced to include easy whelpings in their breeding program

Management issues in systems engineering

When applied to a system, the doctrine of successive refinement is a divide-and-conquer strategy. Complex systems are sucessively divided into pieces that are less complex, until they are simple enough to be conquered. This decomposition results in several structures for describing the product system and the producing system. These structures play important roles in systems engineering and project management. Many of the remaining sections in this chapter are devoted to describing some of these key structures. Structures that describe the product system include, but are not limited to, the requirements tree, system architecture and certain symbolic information such as system drawings, schematics, and data bases. The structures that describe the producing system include the project's work breakdown, schedules, cost accounts and organization

Efficiency and regulation tests of general electric transformer, type H, #497204

Citation: Forsberg, Carl F., Perrine, Arthur A., and McLean, Harry G. Efficiency and regulation tests of general electric transformer, type H, #497204. Senior thesis, Kansas State Agricultural College, 1908.Introduction: The static transformer is a device used for changing the voltage and current relations of an alternating current. It consists, essentially, of a pair of mutually inductive circuits called the primary and secondary coils, and a magnetic circuit interlinked with both coils. This magnetic circuit is called the core of the transforme

Nonlinear Interactions Between Gravitational Radiation and Modified Alfven Modes in Astrophysical Dusty Plasmas

We present an investigation of nonlinear interactions between Gravitational Radiation and modified Alfv\'{e}n modes in astrophysical dusty plasmas. Assuming that stationary charged dust grains form neutralizing background in an electron-ion-dust plasma, we obtain the three wave coupling coefficients, and calculate the growth rates for parametrically coupled gravitational radiation and modified Alfv\'{e}n-Rao modes. The threshold value of the gravitational wave amplitude associated with convective stabilization is particularly small if the gravitational frequency is close to twice the modified Alfv\'en wave-frequency. The implication of our results to astrophysical dusty plasmas is discussed.Comment: A few typos corrected. Published in Phys. Rev.

ACTH: The Uninhibitable (or is it)?

Adrenal corticotropic hormone, or ACTH, is a peptide hormone secreted by the anterior pituitary gland. The full-length peptide is 39 amino acids long. ACTH signals through a G-protein linked receptor in humans, using the adenylyl cyclase pathway. Potassium and chloride channels have also been implicated in human ACTH signaling. Tetrahymena thermophila are free-living, ciliated ptotozoans. These organisms exhibit avoidance behavior toward many polycationic peptides, which serve as chemorepellents. The reason for this is unknown; however, it is hypothesized that natural predators of T. thermophila secrete polycationic peptides, and that polycation avoidance allows T. thermophila to escape predation. We obtained a number of peptides derived from ACTH, including ACTH 1-39, ACTH 1-24, ACTH 11-24, ACTH 6-24, and ACTH 1-14. We hypothesized that the more highly charged peptide derivatives would be the most effective chemorepellents. This hypothesis was proven correct, with the most highly charged ACTH derivative, ACTH 6-24, demonstrated as the most effective chemorepellent. The least charged form of ACTH, ACTH 1-39, was least effective at causing avoidance. We hypothesized that ACTH signaling in T. thermophila would use similar signaling pathways to those previously identified in humans. This, however, has not proven to be the case. We have tested G-protein inhibitors, adenylyl cyclase inhibitors, potassium channel blockers, and chloride channel blockers in T. thermphila. None of these drugs had any measurable effect on ACTH signaling. In addition, we have chelated extracellular calcium (using EGTA) and depleted ER calcium stores (using thapsigargin). Neither of these interventions inhibited ACTH signaling in this organism. Calcium channel blockers also failed to affect avoidance. This is highly unexpected, since all known chemorepellent pathways discovered in Tetrahymena to date are calcium-dependent. It is possible that ACTH is using a novel signaling pathway in T. thermophila. We hope that further testing will enable us to discover more about this signaling mechanism