PROBABILISTIC PRICE FORECASTS BASED ON COMMODITY OPTION VALUES

Demand and Price Analysis,

SEQUENTIAL REGRESSION: A FLEXIBLE TOOL FOR TIME SERIES MODELING

Research Methods/ Statistical Methods,

Reflections On Contributing To “Big Discoveries” About The Fly Clock: Our Fortunate Paths As Post-Docs With 2017 Nobel Laureates Jeff Hall, Michael Rosbash, And Mike Young

In the early 1980s Jeff Hall and Michael Rosbash at Brandeis University and Mike Young at Rockefeller University set out to isolate the period (per) gene, which was recovered in a revolutionary genetic screen by Ron Konopka and Seymour Benzer for mutants that altered circadian behavioral rhythms. Over the next 15 years the Hall, Rosbash and Young labs made a series of groundbreaking discoveries that defined the molecular timekeeping mechanism and formed the basis for them being awarded the 2017 Nobel Prize in Physiology or Medicine. Here the authors recount their experiences as post-docs in the Hall, Rosbash and Young labs from the mid-1980s to the mid-1990s, and provide a perspective of how basic research conducted on a simple model system during that era profoundly influenced the direction of the clocks field and established novel approaches that are now standard operating procedure for studying complex behavior

Localisation of the melanocortin-2-receptor and its accessory proteins in the developing and adult adrenal gland

The melanocortin-2-receptor (MC2R)/MC2R accessory protein (MRAP) complex is critical to the production of glucocorticoids from the adrenal cortex. Inactivating mutations in either MC2R or MRAP result in the clinical condition familial glucocorticoid deficiency. The localisation of MC2R together with MRAP within the adrenal gland has not previously been reported. Furthermore, MRAP2, a paralogue of MRAP, has been shown in vitro to have a similar function to MRAP, facilitating MC2R trafficking and responsiveness to ACTH. Despite similar MC2R accessory functions, in vivo, patients with inactivating mutations of MRAP fail to be rescued by a functioning MRAP2 gene, suggesting differences in adrenal expression, localisation and/or function between the two MRAPs. In this study on the rat adrenal gland, we demonstrate that while MRAP and MC2R are highly expressed in the zona fasciculata, MRAP2 is expressed throughout the adrenal cortex in low quantities. In the developing adrenal gland, both MRAP and MRAP2 are equally well expressed. The MC2R/MRAP2 complex requires much higher concentrations of ACTH to activate compared with the MC2R/MRAP complex. Interestingly, expression of MC2R and MRAP in the undifferentiated zone would support the notion that ACTH may play an important role in adrenal cell differentiation and maintenance

Design of a monitor and simulation terminal (master) for space station telerobotics and telescience

Based on Space Station and planetary spacecraft communication time delays and bandwidth limitations, it will be necessary to develop an intelligent, general purpose ground monitor terminal capable of sophisticated data display and control of on-orbit facilities and remote spacecraft. The basic elements that make up a Monitor and Simulation Terminal (MASTER) include computer overlay video, data compression, forward simulation, mission resource optimization and high level robotic control. Hardware and software elements of a MASTER are being assembled for testbed use. Applications of Neural Networks (NNs) to some key functions of a MASTER are also discussed. These functions are overlay graphics adjustment, object correlation and kinematic-dynamic characterization of the manipulator

Instability of human societies as a result of conformity

We introduce a new model that mimics the strong and sudden effects induced by conformity in tightly interacting human societies. Such effects range from mere crowd phenomena to dramatic political turmoil. The model is a modified version of the Ising Hamiltonian. We have studied the properties of this Hamiltonian using both a Metropolis simulation and analytical derivations. Our study shows that increasing the value of the conformity parameter, results in a first order phase transition. As a result a majority of people begin honestly to support the idea that may contradict the moral principles of a normal human beings though each individual would support the moral principle without tight interaction with the society. Thus, above some critical level of conformity our society occurs to be instable with respect to ideas that might be doubtful. Our model includes, in a simplified way, human diversity with respect to loyalty to the moral principles.Comment: 5 pages, 5 figures, accepted in Int. journ of modern physics section

Investigating intra-host and intra-herd sequence diversity of foot-and-mouth disease virus

Due to the poor-fidelity of the enzymes involved in RNA genome replication, foot-and-mouth disease (FMD) virus samples comprise of unique polymorphic populations. In this study, deep sequencing was utilised to characterise the diversity of FMD virus (FMDV) populations in 6 infected cattle present on a single farm during the series of outbreaks in the UK in 2007. A novel RT–PCR method was developed to amplify a 7.6 kb nucleotide fragment encompassing the polyprotein coding region of the FMDV genome. Illumina sequencing of each sample identified the fine polymorphic structures at each nucleotide position, from consensus level changes to variants present at a 0.24% frequency. These data were used to investigate population dynamics of FMDV at both herd and host levels, evaluate the impact of host on the viral swarm structure and to identify transmission links with viruses recovered from other farms in the same series of outbreaks. In 7 samples, from 6 different animals, a total of 5 consensus level variants were identified, in addition to 104 sub-consensus variants of which 22 were shared between 2 or more animals. Further analysis revealed differences in swarm structures from samples derived from the same animal suggesting the presence of distinct viral populations evolving independently at different lesion sites within the same infected animal

Household Food Expenditures across Income Groups: Do Poor Households Spend Differently than Rich Ones?

The Life Cycle - Permanent Income Hypotheses (LCPIH) suggests that the timing of an income payment or government transfer should have no effect on the expenditures of the recipient. In this paper we test the LCPIH against a dynamic model of household consumption which predicts clustered food expenditure. We use data from 7,013 households in fifty-two urban and peri-urban markets throughout the United States containing detailed daily expenditure data collected by ACNielsen Homescan for 2003. Specifically, we examine aggregate food expenditure patterns, shopping trip patterns, and expenditure patterns across retail channels over calendar weeks, weekly seven day cycles, and days of the week. Our main finding is that households in the lowest 25 percent of the income distribution that have zero employed people have a significantly higher differenced expenditure level in the beginning of the month and significantly lower differenced expenditure in the last week or weeks of the calendar month, thus rejecting the LCPIH. Further, we find that, in general, households do not use convenience stores as a complementary retail channel to the grocery channel.Consumer/Household Economics,

Nonuniqueness in a minimal model for cell motility

Two–phase flow models have been used previously to model cell motility, however these have rapidly become very complicated, including many physical processes, and are opaque. Here we demonstrate that even the simplest one–dimensional, two–phase, poroviscous, reactive flow model displays a number of behaviours relevant to cell crawling. We present stability analyses that show that an asymmetric perturbation is required to cause a spatially uniform, stationary strip of cytoplasm to move, which is relevant to cell polarization. Our numerical simulations identify qualitatively distinct families of travelling–wave solution that co–exist at certain parameter values. Within each family, the crawling speed of the strip has a bell–shaped dependence on the adhesion strength. The model captures the experimentally observed behaviour that cells crawl quickest at intermediate adhesion strengths, when the substrate is neither too sticky nor too slippy