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We studied seismic‐wave generation from five small (60–122 kg) fully contained explosions detonated in Barre Granite as a part of the New England Damage Experiment (NEDE). The explosions were conducted using three types of explosives with different velocities of detonation (VOD): black powder, ammonium nitrate fuel oil (ANFO) emulsion, and composition B (COMP‐B). Empirical evidence suggests that the low VOD explosives produce more shear‐wave energy than high VOD explosives. The proposed mechanisms to explain this effect include: (a) inhibition of gas‐driven fracture propagation by thicker pulverized zone for high VOD explosions, and (b) fracture toughness increase at higher loading rate. The main objective of the experiment was to study differences in shear‐wave generation between different types of explosives, and to determine the likely mechanism responsible for these differences. Seismic amplitude analysis revealed that COMP‐B releases more energy and larger amplitude P waves for the same weight of explosives, while producing smaller amplitude S waves. Furthermore, large radial cracks were observed on the surface after the ANFO and black powder shots, while there was no surface fracturing after the COMP‐B shots. Thus, longer fractures correlate with higher S ‐wave amplitudes. However, drilling into the source region indicates that high VOD explosions may actually produce a smaller pulverized zone, which means that fracture inhibition is a less plausible explanation. Therefore we hypothesize that increase in loading rate, in combination with shorter impulse duration for high VOD explosives, inhibits fracture processes, and subsequently reduced S ‐wave radiation.

Background: Research conferences generally cluster scientists by discipline and limit cross-disciplinary communication. Rushed presentations frequently truncate messages. Travel costs prevent most scientists from ever meeting one another. And delays prior to publication and [sometimes] year-long web-posting embargoes impede the progress we all desire. In some research areas preclinical and clinical trials have replication problems so severe that the US-National Institutes of Health funded a replication program which then failed to replicate 15 of 16 key studies [see PMIDs: 18838063,22078760,22134153,22177997]. Because the plenary discussion of the first large-scale healthspan/longevity trial, the TAME trial (Targeting/Taming Aging with MEtformin), was cut short by time constraints, a communication group formed to continue the healthspan-trial-design discussion after the American Aging Association conference (AAA-2016), thereby improving/speeding communication between conferees and with IAGG-2017 and other healthspan-related conferences.

Attempts to evaluate the sulphur hexafluoride (SF 6 ) tracer technique to estimate CH 4 emissions from ruminants have yielded mixed results. These studies either used SF 6 permeation tubes with a long history of use in animals, involved small number of animals or used partial animal enclosure. Our study was conducted with a relatively large number of experimental sheep and controlled variables regarding the permeation rate (PR) of SF 6 . Twenty four sheep housed in a covered yard and fed lucerne silage to achieve common feed intakes among individuals in the study were administered fresh SF 6 permeation tubes. Following 10 d acclimatisation in pens, sheep were staggered in 3 groups of 8 each in order to match availability of 8 respiration chambers. Each group were transferred to individual metabolic crates and habituated to breath collection harnesses for 3 d before breath samples were collected daily over 6 consecutive d for CH 4 emission estimation using the SF 6 ‘Tracer’ technique. Sheep were then brought into respiration chambers for CH 4 measurements over 4 consecutive d (‘Chamber’). During sheep occupation, chamber inlet and outlet gas streams were sampled into evacuated yokes, as for the tracer technique procedures. Samples were analysed for CH 4 and SF 6 mixing ratios by gas chromatography as for the Tracer technique, which were then used to estimate CH 4 emissions using tracer technique procedures ( i.e. , Tracer in chamber). Paired t-tests based on within sheep data were used for pairwise comparisons of CH 4 emission estimates between techniques. Daily CH 4 emissions for the Tracer, Chamber and Tracer in chamber procedures were 14.8 ± 2.4, 13.9 ± 1 and 16.1 ± 2.8 g, respectively. Although Tracer and Chamber emission estimates did not differ, Tracer estimates were associated with much larger among- and within-animal variability than Chamber values, and the relationship between Chamber and Tracer estimates was poor. Rate of recovery of SF 6 from chamber gases calculated by dividing the calculated daily emission of SF 6 ( i.e. , net mixing ratio of SF 6 × chamber ventilation rate) by the known PR of SF 6 was 10% lower than that for CH 4 . In sheep, the average CH 4 emission estimate using the SF 6 tracer technique matches that obtained from chambers, but the correlation between estimates is poor, possibly due to a mismatch in routes of excretion of tracer and trace gases. This article is part of the special issue entitled: Greenhouse Gases in Animal Agriculture – Finding a Balance between Food and Emissions, Guest Edited by T.A. McAllister, Section Guest Editors; K.A. Beauchemin, X. Hao, S. McGinn and Editor for Animal Feed Science and Technology, P.H. Robinson.

Nuclear monitoring agencies often use seismic amplitudes to estimate the yields of underground nuclear tests. Any emplacement phenomena that can alter those amplitudes and lead to bias in estimated yields must be considered in the analysis. One condition that might cause such a bias is detonation in frozen rock. Laboratory analyses (Mellor, 1971; Miller and Florence, 1991) have shown that frozen rock has faster seismic velocity and greater compressive strength than unfrozen rock. This increased strength is hypothesized to reduce the seismically estimated yield of an explosion in frozen rock. To test this hypothesis, we conducted the Frozen Rock Experiment (FRE), a series of explosions in frozen and unfrozen rock, in central Alaska during August 2006. Over 120 seismic instruments were deployed to record six detonations—three in frozen and three in unfrozen-dry media—at a wide range of distances and azimuths. The data acquired show that the frozen test site explosions had significantly larger amplitudes for all phases ( P , S , and surface waves) above 8–10 Hz. These data confirm that the frozen rock medium was stronger and resulted in a smaller seismic source radius for the explosions, thus increasing the corner frequency when compared to the unfrozen rock explosions. Between 3 and 9 Hz, the unfrozen shots produced slightly larger S and surface waves resulting in different P / S spectral ratio plots for the frozen and unfrozen shots, possibly affecting regional phase discrimination. We show that the observed amplitude differences for these shots can be effectively modeled using the Mueller-Murphy (1971) explosion source and the in situ P - and S -wave velocities for the two test sites. Differences in the velocities at the frozen and unfrozen rock test sites are caused by minor metamorphic facies changes, saturated versus dry conditions, and the presence of ice in the pores and fractures at the frozen test site. Extrapolation of the results of this study to synthetic nuclear explosions suggests there may not be significant coupling differences between explosions in frozen and unfrozen hard rock.

The Irrigation Calculator is a computer decision support tool that assists dairy farmers to decide when to irrigate, how much water to apply, and the consequences of wrong irrigation timings or amounts. The user interface has two data entry screens, one to enter background soils information, the other main screen for entering irrigator application times and amounts, grazings and run times. Keywords: model, pasture growth, soil moisture, evapotranspiration

We review studies on the pharmacology and mode of action of pyrantel and comment on its analogs, oxantel and morantel, where appropriate. Pyrantel is a fairly selective agonist of nematode nicotinic acetylcholine receptors (nAChRs). Pyrantel produces depolarization and contraction of nematode body muscle which causes spastic paralysis; it is a relatively potent agonist (EC50~10 µM) on levamisole receptor subtypes of nematode nAChRs. In addition, pyrantel has open-channel blocking effects which reduce the response at higher agonist concentrations, weak anticholinesterase effects, and nicotinic agonist effects at higher concentrations in vertebrate tissues; pyrantel causes spastic paralysis in chicks, contracts the frog rectus abdominis muscle, depolarizes the end-plate potential in the rat hemi-diaphragm, and causes depolarization and then neuromuscular block in the cat soleus and tibialis muscle preparations. Pyrantel selectively activates a subgroup of nematode nAChRs and at toxic doses has effects on host nAChRs.

Bronchopulmonary dysplasia (BPD) in preterm infants is associated with impaired alveolar growth, inflammation and airway hyperreactivity. In animal models of BPD, inhaled nitric oxide (NO) improves alveolar growth and inhibits airway smooth muscle proliferation. This study was designed to assess the effect of inhaled NO on resistance and compliance in ventilated preterm infants with evolving BPD.Expiratory resistance and compliance of the respiratory system were measured in 71 ventilated preterm infants,or = 32 weeks gestation, randomized to NO (n=34) versus placebo (n=37) foror = 24 days at 7 to 21 days of life.At baseline expiratory resistance (231+/-71 versus 215+/-76 cm H(2)O l(-1) s(-1)) and compliance (0.49+/-0.14 versus 0.53+/-0.13 ml cm H(2)O(-1) kg(-1)) were comparable between placebo and NO groups, respectively. There was no effect of NO on expiratory resistance or compliance at 1 h, 1 week or 2 weeks of study gas administration.NO had no short- or medium-term effect on expiratory resistance or compliance in ventilated preterm infants.

As the availability of water for irrigation becomes more limiting it is important to use the available water effectively and all potential avenues for improving irrigation efficiency should be examined. Improving irrigation system uniformity can lead to production gains and less loss of water through drainage, but such data are difficult to collect experimentally. Keywords: irrigation variability, LUCI, simulation modelling

Oca ( Oxalis tuberosa Mol.), known as yam in New Zealand, has been grown commercially for more than a century. More recently, yellow and orange cultivars have been introduced to complement the traditional pink cultivar. This study investigates the composition and colour of three introduced lines, a hybrid between two of these lines and a local yellow cultivar, including the first reported measurements of oca vitamin C content. The CIE L ∗ a ∗ b ∗ colour of the skin and tissue were measured in the raw tubers and after boiling and baking, the most common way to cook the tubers. The skin and the tissue of all the cultivars were a very similar orange–yellow when cooked. The soluble oxalate, vitamin C, pH and titratable acidity were also measured in the raw and cooked tissue. On a dry matter basis, the mean soluble oxalate of the raw cultivars was 935.5 ± 125.7 mg/100 g DM rising to 1364.8 ± 217.5 mg/100 g DM when baked; in contrast, the mean vitamin C content of the raw tubers was 109.8 ± 28.9 mg/100 g DM falling to a mean of 62.4 ± 12.1 mg/100 g DM when the tubers were baked.

We introduce a point source model which may be useful for estimating point sources in spatial data. It may also be useful for modelling general spatial data, and providing a simple explanatory model for some data, whilst in other cases it may give a parsimonious representation. The model assumes that there are point sources (or sinks), usually at unknown positions, and that the mean value at a site depends on the distance from these sources. We discuss the general form of the model, and some methods for estimating the sources and the regression parameters. We demonstrate the methodology using a simulation study, and apply the model to two real data sets. Some possibilities for further research are outlined.

Water Use Efficiency (WUE) is an important performance indicator of sustainable production, widely used overseas. WUE is defined in a number of ways, and it is important to know what definition is being used. Overseas data show that WUE on dairy farms depends on both the efficiency of applying water to the paddock, and the efficiency of feed utilisation off the paddock. Pasture WUE requires measurements of the amount of water applied and the amount of pasture produced, which are rarely concurrently measured on dairy farms. Estimates of pasture WUE from previous research experiments are highly variable because of uncertainties about how much water was applied. We have suggested a benchmark for WUE based on measurements on commercial dairy farms, and suggest some ways that farmers can improve their irrigation practices. Keywords: water use efficiency, pasture yield, irrigation, evapotranspiration

The amino acids cysteine, glycine, serine and tyrosine all increased steadily during evolution of primate to human milk, hinting that this combination may support the extraordinary human longevity which co-evolved. Methionine continued its long downward trend during primate evolution, so this amino acid declined steadily in heart tissue and then milk proteins from mice to man, spanning cat, dog, cow, horse and elephant evolution as well as rodent and primate. These amino acid changes are sufficiently precise to enable unbiased SIMCA multivariate analysis to predict primate/human lifespan with 99 percent accuracy, and to score and map all foods within the US Department of Agriculture Nutrition Database (Release 26) into zones comprised of proportions resembling short-lived species, or milk from the longest-lived primates. This presentation provides a tour of foods with longevity-correlated proportions, generally higher in serine and tyrosine and lower in methionine, which map together in 20-dimensional amino-acid-space near human milk, caviar and germ-line tissues that defy aging indefinitely. These carefully-evolved proportions are then linked to daily circadian peak periods of high methionine and genetic damage that by hypothesis represent a burst of daily aging that occurs unless we protect ourselves by carefully selecting nutrient proportions at each meal (either baboon-like proportions or non-aging-germ-line proportions). Longevity-linked ratios in burritos are then shown to predict surprisingly low rates of Alzheimer’s, cancer, heart disease, stroke and other age-associated illnesses within Hispanic-Americans aged 80 and above, and the partial reversal of advanced kidney disease when cats are fed a specially-formulated kidney-support diet.

As part of the Collaborative Home Infant Monitoring Evaluation (CHIME) we compared apnea identified by a customized home monitor using respiratory inductance plethysmography (RIP) with simultaneously recorded polysomnography-acquired nasal end-tidal CO2 (Pet CO2 ) and nasal/oral thermistor in 422 infants during overnight laboratory recordings to determine concordance between techniques, sources of disagreement, and capacity of RIP to detect obstructed breaths within an apnea. Among 233 episodes of apnea identified by at least one method as ⩾ 16 s, 120 were observed by the CHIME monitor, 219 by Pet CO2 , and 163 by thermistor. The positive predictive value of the CHIME-identified apnea was 89.2% (95% CI 83, 95) and 73% (95% CI 65, 81) for Pet CO2 and thermistor, respectively. However, the sensitivity of the CHIME monitor in identifying events detected by the other methods was only ∼ 50%. Among 87 apnea events identified by all three techniques, no two methods showed high agreement in measurement of apnea d...

Nonlinear systems increase signal bandwidth, but Volterra systems may be identified uniquely even when the output is sampled at the Nyquist rate of the input. We present a more transparent and general proof. Using the theory of sampling expansions for general integral transforms, we permit the sampling to be nonuniform.

This paper examines the potential of a biological activity control system (BACS) for biological activated carbon (BAC) in comparison to granular activated carbon (GAC) for the treatment of potable water. The overall objective of the project is to produce drinking water of a higher quality more economically by developing a BACS for exhausted GAC that can be transformed to BAC by the development of a natural biofilm during the bio-regeneration mode. The research therefore may be interesting for water companies and the activated carbon industry. Findings show that the lifetime of a GAC filter can be significantly extended by maintaining an active biofilm that has to be controlled in order to avoid filter clogging. The most important parameters are dissolved oxygen (DO), pH and a correct balance of nutrients, which enables a natural control of the biomass. pH control was required to maintain an optimal bacteria-protozoa level. Excessive growth of filamentous bacteria can be prevented by a decrease in DO, increase in pH and the reduction of one essential nutrient, e.g. total phosphorus (P). Total organic carbon (TOC) and chemical oxygen demand (COD) values were reduced by bioactivity. DO, turbidity and suspended solids (SS) values were kept in acceptable ranges with respect to drinking water objectives. Plants without a significant population of protozoa deliver turbid low quality effluent high on SS and biochemical oxygen demand (BOD). It was possible to control the biofilm on GAC containing a natural biofilm and BAC during the bio-regeneration mode. Natural and artificial bio-regeneration lead to similar performance characteristics.

The three-dimensional nearest-neighbour process is considered, and some of its properties are derived. It is shown that the correlations are difficult to obtain, and that it is possible for them to decay very slowly.

We present and demonstrate a new method for accurately determining the radial component of sea current, using information derived from HF radar returns. The method uses autoregressive modeling and constrains the estimated frequency separation of the first-order Bragg lines to be its required theoretical value of 2/spl radic/(gf//spl pi/c), where f is the radar frequency.

The order three to five spatially-distinct Latin squares, and the order three to six spatially-distinct Latin square treatment designs are listed. Some statistical results are given. Designs for 4, 5 and 6 treatments that were found previously to be robust to a linear by linear interacrion are shown to be optimal. Designs with good neighbour balanced are also considered.

The Fisher information loss on the dependence parameter is considered for three one-parameter Gaussian processes on a rectangular lattice when some values are not observed. Formulae are given for the general case, and simplified versions for two of the special cases. Approximations are considered, and cases with a small number of missing sites are compared.

In this paper the theory of light scattering by slightly non-spherical particles is developed and the forms of the amplitude and Stokes scattering matrices are derived. Forward-scatter and backscatter and the information they give about the shape of the particle are discussed as special cases.

Randomization is considered when errors are spatially dependent and the analysis uses generalized least-squares for a known dependence structure. It is shown that valid randomization sets do exist, but that the designs within a set do not have constant C matrices. It is also shown that a valid randomization set for the usual analysis in which all designs have constant C matrices does not form a valid randomization in the generalized analysis.

We present a 3D Earth Model of the Arabian Plate and demonstrate its use for the rapid assessment of play potential, with an example from the Khuff gas play in eastern Arabia. The model encompasses all strata from basement to surface, and covers an area of c. 1,200 by 1,200km with a grid size of 10km. Based on our robust sequence stratigraphic framework and a database of publically available information, the model is divided into 82 layers corresponding to key 1st, 2nd and 3rd order depositional sequences. Applied to the Khuff gas play, this enables us to rapidly produce (and update with new data if needed) a regional play risk map for the Khuff and identify areas of higher potential for this play.

Weston Geophysical Corporation (WGC) and New England Research, Inc. (NER) conducted the New England Damage Experiment (NEDE) in July 2008. The experiment included the detonation of chemical explosions in relatively unfractured, homogeneous Barre granite in Vermont, USA. Barre granite has been a worldwide standard for homogeneous, low fracture-density granite in commercial, monument, and industrial settings. The emplacement granite was characterized before and after the experiment using borehole cores and acoustic imaging. The explosions were designed with variable velocities of detonations (VOD) to fracture the rock differently. Our hypothesis was that different damage would lead to possible variations in S wave generation. During the past year, we have quantified the damage from the explosions on micro, meso, and macro scales and examined the seismic wave generation and propagation at near-source, local, and regional distances.

Regional play evaluation demands the integration of large volumes of data and information from a wide variety of sources, including wells, seismic, facies maps, structure maps and the results of basin modelling. Historically a task for an experienced explorer and a light table, the advent of geographical information systems (GIS) allows greater efficiencies and some automation of workflows, but still does not offer complete integration of data, applications and products. Furthermore, these data must lie in their wider geographical and stratigraphic context, thus requiring a regional Earth Model. We present here a 3D Shared Earth Model of the Arabian Plate in Petrel 2011*, and demonstrate its use for regional play evaluation. With an example from the Khuff gas play of eastern Arabia, we show how modern 3D workflows offer advantages to previous GIS-based techniques, and emphasize the greater efficiencies which can be realised through strong integration of all data and their interpretations within the final assessment. *A mark of Schlumberger

Background: Intermittent hypoxic episodes are common among preterm infants, although longer term consequences on growth pattern and cardiovascular regulation are unclear. Furthermore, the effects of intermittent hypoxia (IH) may depend on the pattern of hypoxia-reoxygenation. Objectives: We tested the hypothesis that a clustered versus dispersed pattern of repetitive IH during early postnatal life would induce differential long-term alteration in growth and cardiovascular regulation. Methods: Sprague-Dawley rat pups were exposed to room air or to one of two patterns of IH (clustered vs. dispersed) from 1 to 7 days of life. Body weight was measured daily for the first 8 days and weekly from weeks 2 to 8. Blood pressure (BP) and heart rate were measured weekly from weeks 4 to 8 using a noninvasive tail-cuff method for awake, nonanesthetized animals. Results: Exposure to both patterns of repetitive IH induced early growth restriction followed by later catch-up of growth to controls 3 weeks after completion of IH exposures. IH-exposed rats exhibited a sustained decrease in heart rate regardless of the hypoxic exposure paradigm employed. In contrast, a differential response was seen for arterial pressure; the clustered paradigm was associated with a significantly lower BP versus controls, while the pups exposed to the dispersed paradigm showed no effect on BP. Conclusion: We speculate that repetitive IH during a critical developmental window and regardless of IH exposure paradigm contributes to prolonged changes in sympathovagal balance of cardiovascular regulation.

While using the standard Mie formulae to calculate the intensity distribution of light scattered by a small dielectric sphere, we have noticed some new qualitative results which suggest a boundary between a scattering regime qualitatively similar to the well known Rayleigh scattering distribution and that observed for rather larger particles. This may be of practical use when considering the position of photodetectors in light scattering experiments, for example particle velocimetry. The reason for such a transition has been discovered, using an unusual approximation in which the diameter of a sphere is made very small and its refractive index very large, with their product and the wavelength held constant.

When modelling continuous regional data, it is common to model the regional variables themselves. For example, in geographic modelling, it is usual to specify the inverse covariance matrix in a simple form. However, in many situations it may be plausible to model an underlying continuous-space process. In order to postulate reasonable models, the behaviour of the derived regional process needs to be known. For exact Gaussian maximum likelihood estimation the covariance structure of the derived process may be needed for a large number of parameter values of the underlying process, and so may be computationally infeasible. This paper considers approximate relationships between the original and derived covariance structures for irregular regions. The derived covariance structures are compared with some geographic models in common use, and alternative models are postulated.

A series of constant strain rate, unconfined compression experiments was performed on saturated welded tuff specimens collected from Busted Butte near Yucca Mountain, Nevada. Twenty specimens were loaded to failure at strain rates ranging from 10{sup {minus}9}s{sup {minus}1} to 10{sup {minus}3}s{sup {minus}1}, under ambient pressure and temperature conditions. The strength of the specimens showed a continuous decrease with decreasing strain rate between 10{sup {minus}9} s{sup {minus}1} and 10{sup {minus}5} s{sup {minus}1}. At the highest strain rate, 10{sup {minus}3} s{sup {minus}1}, strengths were less than those observed at 10{sup {minus}5} s{sup {minus}1}, likely due to hydrofracturing within the specimen at rapid loading rates. Reduction in strength, corresponding to the decrease in strain rate, is explained in terms of stress corrosion cracking. A detailed examination of six specimens tested at a strain rate of 10{sup {minus}9} s{sup {minus}1}, using acoustic wave velocities and CT scans, shows a correlation between the nature of the microstructure of the specimens and the observed strengths and elastic moduli.

The Nyquist constraint for regular sampling of multiband signals is that the sampling rate must fall in an "allowed band". For random sampling, the sampling rate only has to exceed the Nyquist-Landau rate (information rate), which is a simpler constraint. We demonstrate this flexibility in a simulation of a communication channel.

A Held experiment was conducted to evaluate the effect of various rates and timings of nitrogen (N) fertiliser application on yield, grain quality, quantities of various classes of proteins, and milling and baking characteristics of New Zealand wheat cultivars. Six cultivars of autumn-sown wheat—‘Batten’, ‘Kotare’, ‘Oroua’, ‘Rongotea’, ‘Ruapuna’, and ‘Tui’—were grown under five N fertiliser treatments: no N; 50kg N/ha applied at late tillering; 50 kg N/ha applied at both late tillering and booting; 100 kg N/ha applied at late tillering; and 100 kg N/ha applied at late tillering and 50 kg N/ha applied at booting. The site was severely N depleted and ear numbers were low. However, weight per grain was high andrelatively unaffected by N fertiliser. Grain yield, grain protein, and Mechanical Dough Development (MDD) Bake Score increased with increasing fertiliser N, irrespective of time of application,but, between cultivars,yield was inversely related to both grainprotein and bake score. No one cultiv...

We introduce a new model, the harmonic correlation process, for slowly-decaying correlations. The model has some interesting theoretical properties, which we discuss, and appears to be useful as a practical model. We outline some areas for further research.

We use the contour integral method to develop a "one-sided" sampling series. With the classical sampling theorem, arbitrarily good interpolation accuracy requires infinitely samples on each side of the point. With one-sided sampling series, only past samples are needed. A simple expansion and associated truncation error bound are derived, and numerical simulations are shown.