Zero-one IP problems: Polyhedral descriptions & cutting plane procedures

A systematic way for tightening an IP formulation is by employing classes of linear inequalities that define facets of the convex hull of the feasible integer points of the respective problems. Describing as well as identifying these inequalities will help in the efficiency of the LP-based cutting plane methods. In this report, we review classes of inequalities that partially described zero-one poly topes such as the 0-1 knapsack polytope, the set packing polytope and the travelling salesman polytope. Facets or valid inequalities derived from the 0-1 knapsack and the set packing polytopes are algorithmically identifie

Optimization of High-Strength Hydrocarbon Biodegradation Using Respirometry

Laboratory respirometry experiments were conducted on mixtures of soil and oily sludge to estimate biodegradation rates by CO2 production rates and determine optimum conditions for biodegradation of high-strength hydrocarbon waste products. These experiments were used to determine a suitable range of total petroleum hydrocarbon (TPH) concentration for biological treatment and to optimize for nutrient addition and moisture content. CO2 production rates from biological respiration of hydrocarbon-contaminated soil were maximized at concentrations of 3-9% TPH (30,00090,000 mg/kg TPH). CO2 production rates decreased dramatically at concentrations above 9% TPH, indicating that either these concentrations are lethal to microbes present, or this high sludge content inhibits aeration of the soils. Addition of 120 mg/kg nitrogen, 40 mg/kg phosphorous, and 40 mg/kg potassium to the soils resulted in a three fold increase in CO2 production rates. No significant increase in CO2 production was observed when the nutrient addition was increased to 240 mg/kg nitrogen, 80 mg/kg phosphorous, and 80 mg/kg potassium. Maximum CO2 production rates were observed at 15-20% moisture content. CO2 production rates decreased significantly at and below 10% moisture and at and above 25% moisture. Maximum CO2 production rates observed for soil with 50,000 mg/kg TPH, with added nutrients at optimum moisture content, were 30-35 μL CO2/g/hr. Assuming all CO2 was generated from hydrocarbon degradation, this maximum CO2 production rate corresponds to a hydrocarbon biodegradation rate of approximately 500 mg TPH/kg/day (assuming 100% respiration for a conservative estimate). If ideal conditions are maintained and rates of respiration remain high, clay soil contaminated with 60,000 mg/kg TPH sludge could probably be remediated in 2 months

Biases in the perceived timing of perisaccadic perceptual and motor events

Subjects typically experience the temporal interval immediately following a saccade as longer than a comparable control interval. One explanation of this effect is that the brain antedates the perceptual onset of a saccade target to around the time of saccade initiation. This could explain the apparent continuity of visual perception across eye movements. Thisantedating account was tested in three experiments in which subjects made saccades of differing extents and then judged either the duration or the temporal order of key events. Postsaccadic stimuli underwent subjective temporal lengthening and had early perceived onsets. A temporally advanced awareness of saccade completion was also found, independently of antedating effects. These results provide convergent evidence supporting antedating and differentiating it from other temporal biases

Visual onset expands subjective time

We report a distortion of subjective time perception in which the duration of a first interval is perceived to be longer than the succeeding interval of the same duration. The amount of time expansion depends on the onset type defining the first interval. When a stimulus appears abruptly, its duration is perceived to be longer than when it appears following a stationary array. The difference in the processing time for the stimulus onset and motion onset, measured as reaction times, agrees with the difference in time expansion. Our results suggest that initial transient responses for a visual onset serve as a temporal marker for time estimation, and a systematic change in the processing time for onsets affects perceived time

Prevalence of six viral and bacterial diseases in wild hogs in South Carolina (2007-2013)

The wild hog (Sus scrofa) is an invasive species that can pose a serious threat to native ecosystems, the domestic livestock industry, and human health. It is estimated that wild hog damage in the United States amounts to roughly $1.5 billion each year; however, this estimate could substantially increase if wild hogs transmitted a viral or bacterial disease to the country’s domestic livestock industry. From 2007-2013, blood and nasal secretion samples were collected from 629 wild hogs in South Carolina to test for 6 selected diseases including classical swine fever, swine brucellosis, pseudorabies virus, porcine circovirus, porcine reproductive and respiratory syndrome, and swine influenza virus all of which can be transmitted to domestic livestock. The sex, age class, and geographic location of each wild hog sampled were also recorded. Results indicate that age class was significantly associated with swine brucellosis, pseudorabies virus, and porcine circovirus prevalence. Positive swine brucellosis, pseudorabies virus, and porcine circovirus samples were found in 50.0-92.3% of counties sampled. Because wild hogs are present in every county of South Carolina, this information is crucial to determine disease hotspots in the state and can be shared with at-risk individuals and domestic livestock operations in affected counties

ASSESSING AND REDUCING SOYBEAN CROP LOSSES FROM DEER: AN INTERDISCIPLINARY, MULTI-AGENCY EFFORT

Damage from white-tailed deer (Odocoileus virginianus) has become a common complaint of soybean (Glycine max) producers in many areas of the Southeast. Both short- and long-term, single-field and community-wide solutions to this problem are needed. This paper describes a multi-agency, multi-state effort, involving agronomists, wildlife biologists, producers, and other landowners, to assess soybean losses from deer and to evaluate potential solutions. One phase of this work, which is supported by soybean producer checkoff funds, involves evaluating agronomic practices for reducing crop losses. These include drilled (rather than wide-row) plantings and use of insect-resistant or dense-pubescent cultivars (varieties) which may deter browsing, especially where deer pressure is light to moderate. Evaluations of these practices, in comparison with conventional ones, are being conducted in producer’s fields in SC, NC, and VA. The other phase of this work is a cooperative project involving Clemson University, the SC Wildlife and Marine Resources Department, soybean producers and’ other landowners in a 7500-acre tract in Hampton and Jasper Cos., SC. The deer population in this tract will be monitored and reduced over a 3-year period, and the resulting effects on soybean crop losses and herd quality will be assessed

ASSESSING AND REDUCING SOYBEAN CROP LOSSES FROM DEER: AN INTERDISCIPLINARY, MULTI-AGENCY EFFORT

Damage from white-tailed deer (Odocoileus virginianus) has become a common complaint of soybean (Glycine max) producers in many areas of the Southeast. Both short- and long-term, single-field and community-wide solutions to this problem are needed. This paper describes a multi-agency, multi-state effort, involving agronomists, wildlife biologists, producers, and other landowners, to assess soybean losses from deer and to evaluate potential solutions. One phase of this work, which is supported by soybean producer checkoff funds, involves evaluating agronomic practices for reducing crop losses. These include drilled (rather than wide-row) plantings and use of insect-resistant or dense-pubescent cultivars (varieties) which may deter browsing, especially where deer pressure is light to moderate. Evaluations of these practices, in comparison with conventional ones, are being conducted in producer’s fields in SC, NC, and VA. The other phase of this work is a cooperative project involving Clemson University, the SC Wildlife and Marine Resources Department, soybean producers and’ other landowners in a 7500-acre tract in Hampton and Jasper Cos., SC. The deer population in this tract will be monitored and reduced over a 3-year period, and the resulting effects on soybean crop losses and herd quality will be assessed

Illusory perceptions of space and time preserve cross-saccadic perceptual continuity

When voluntary saccadic eye movements are made to a silently ticking clock, observers sometimes think that the second hand takes longer than normal to move to its next position. For a short period, the clock appears to have stopped (chronostasis). Here we show that the illusion occurs because the brain extends the percept of the saccadic target backwards in time to just before the onset of the saccade. This occurs every time we move the eyes but it is only perceived when an external time reference alerts us to the phenomenon. The illusion does not seem to depend on the shift of spatial attention that accompanies the saccade. However, if the target is moved unpredictably during the saccade, breaking perception of the target's spatial continuity, then the illusion disappears. We suggest that temporal extension of the target's percept is one of the mechanisms that 'fill in' the perceptual 'gap' during saccadic suppression. The effect is critically linked to perceptual mechanisms that identify a target's spatial stability

Zoledronate treatment duration is linked to bisphosphonate‐related osteonecrosis of the jaw prevalence in rice rats with generalized periodontitis

ObjectivesTo determine the extent that zoledronate (ZOL) dose and duration is associated with bisphosphonate‐related osteonecrosis of the jaw (BRONJ) prevalence in rice rats with generalized periodontitis (PD), characterize structural and tissue‐level features of BRONJ‐like lesions in this model, and examine the specific anti‐resorptive role of ZOL in BRONJ.Materials and MethodsRice rats (n = 228) consumed high sucrose‐casein diet to enhance generalized PD. Groups of rats received 0, 8, 20, 50 or 125 µg/kg IV ZOL/4 weeks encompassing osteoporosis and oncology ZOL doses. Rats from each dose group (n = 9–16) were necropsied after 12, 18, 24 and 30 weeks of treatment. BRONJ‐like lesion prevalence and tissue‐level features were assessed grossly, histopathologically and by MicroCT. ZOL bone turnover effects were assessed by femoral peripheral quantitative computed tomography, serum bone turnover marker ELISAs and osteoclast immunolabelling.ResultsPrevalence of BRONJ‐like lesions was significantly associated with (a) ZOL treatment duration, but plateaued at the lowest oncologic dose, and (b) there was a similar dose‐related plateau in the systemic anti‐resorptive effect of ZOL. ZOL and BRONJ‐like lesions also altered the structural and tissue‐level features of the jaw.ConclusionThe relationship between BRONJ‐like lesion prevalence and ZOL dose and duration varies depending on the co‐ or pre‐existing oral risk factor. At clinically relevant doses of ZOL, BRONJ‐like lesions are associated with anti‐resorptive activity.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149302/1/odi13052.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149302/2/odi13052_am.pd