Effect of Timing and Intensity of Drought on Perennial Ryegrass Seed Yield

Perennial ryegrass seed worth about $50 million is produced annually in Canterbury, New Zealand (Rowarth 1998). Ryegrass seed production in New Zealand is often affected by drought, reducing both seed number and seed size (Rolston et al., 1994). Irrigation management recommendations are not currently available for farmers growing ryegrass seed crops. To quantify the effect of water stress on perennial ryegrass seed yield, we carried out an experiment in a rainshelter where rainfall was excluded from experimental plots otherwise exposed to normal weather (Martin et al., 1990)

Negotiated control between the manual and visual systems for visually guided hand reaching movements

Abstract Background Control of reaching movements for manual work, vehicle operation, or interactions with manual interfaces requires concurrent gaze control for visual guidance of the hand. We hypothesize that reaching movements are based on negotiated strategies to resolve possible conflicting demands placed on body segments shared by the visual (gaze) and manual (hand) control systems. Further, we hypothesize that a multiplicity of possible spatial configurations (redundancy) in a movement system enables a resolution of conflicting demands that does not require sacrificing the goals of the two systems. Methods The simultaneous control of manual reach and gaze during seated reaching movements was simulated by solving an inverse kinematics model wherein joint trajectories were estimated from a set of recorded hand and head movements. A secondary objective function, termed negotiation function, was introduced to describe a means for the manual reach and gaze directing systems to balance independent goals against (possibly competing) demands for shared resources, namely the torso movement. For both systems, the trade-off may be resolved without sacrificing goal achievement by taking advantage of redundant degrees of freedom. Estimated joint trajectories were then compared to joint movement recordings from ten participants. Joint angles were predicted with and without the negotiation function in place, and model accuracy was determined using the root-mean-square errors (RMSEs) and differences between estimated and recorded joint angles. Results The prediction accuracy was generally improved when negotiation was included: the negotiated control reduced RMSE by 16% and 30% on average when compared to the systems with only manual or visual control, respectively. Furthermore, the RMSE in the negotiated control system tended to improve with torso movement amplitude. Conclusions The proposed model describes how multiple systems cooperate to perform goal-directed human movements when those movements draw upon shared resources. Allocation of shared resources can be undertaken by a negotiation process that is aware of redundancies and the existence of multiple solutions within the individual systems.http://deepblue.lib.umich.edu/bitstream/2027.42/134579/1/12984_2012_Article_626.pd

Provenance of building stones in four 'galley castles' in Argyll

This report describes the outcomes of a project to assess the character and provenance of decorative stones in four ‘galley castles’ in Argyll. This includes a comparative investigation with a number of potential sources of sandstone and metamorphic rocks in Argyll and the surrounding region, which could have been quarried in the past

Source, character and weathering style of building stone in Culzean Castle & Country Park, Ayrshire

This report describes an assessment of the source, character and weathering style of the building stone that has been used in Culzean Castle and other historic structures that lie within Culzean Castle & Country Park (CCCP), in Ayrshire. The assessment was conducted by the Building Stones team of the British Geological Survey (BGS) on behalf of National Trust for Scotland (NTS). The project was funded by Historic Scotland, and the work has been conducted under the Memorandum of Agreement (2011-2016) between Historic Scotland and Natural Environment Research Council (NERC; as represented by BGS). The main building stone in CCCP structures is sandstone sourced locally from the Swanshaw Sandstone Formation. Descriptions of the quarries that are thought to have supplied the stone, and a brief assessment of the potential for obtaining new supplies of the same stone from these and other quarries, are presented in section 2 of this report. The results of a brief review of historical records of local quarrying activity and building history in CCCP are tabulated in an appendix and presented in section 3 as a ‘timeline’. The geological character of Swanshaw sandstone is described in section 4, and the main causes of weathering in sandstone are reviewed briefly in section 5. The character of weathering in the stonework of CCCP buildings, and some of the factors that are likely to be causing accelerated stone decay, are described in section 6. Recommendations for ‘best practice’ procedure in the long-term repair and maintenance of stonework in CCCP are presented in section 7. Key conclusions are summarised in section 8

Argyll & Bute Stone Project stage 1 : scoping study

This report describes the outcomes of a desktop study to review the building stones that were produced historically in the area administered by Argyll and Bute unitary authority council, and identify those that have the best prospect of commercial success if they were brought back to market today. The project, which was commissioned by Historic Environment Scotland (HES) with Highlands and Islands Enterprise as a funding partner, is the first stage of a larger project seeking to bring about renewed building stone production in Argyll and Bute. The report contains summary details for 24 building stones that are currently recognised in Argyll and Bute, and 154 quarries that are associated with these stones. A range of information for each stone is provided, including a list of the end-uses to which it might be suited today, an evaluation of its 'heritage value', and an assessment of the commercial environment into which it would be introduced if quarrying was renewed. This information is used to compile a shortlist of the building stones and quarries that are considered to have the most promising market potential, based mainly on the properties and pedigree of each stone, accessibility of the quarries, and the degree to which 'competitor stones' already exist in the market. Our assessment suggests that Furnace Porphyry, Cruachan Granite, Quarry Granite, Ross of Mull Granite, Highland Border Slate and West Highland Slate have the best potential for renewed production

Low-Temperature Thermochronology of the Chatkal-Kurama Terrane (Uzbekistan-Tajikistan): Insights Into the Meso-Cenozoic Thermal History of the Western Tian Shan

The Chatkal-Kurama terrane represents a key region in understanding the tectonic evolution of the western Tian Shan. In this contribution, we present new thermochronological data (zircon [U-Th-Sm]/He, apatite fission track, and apatite [U-Th-Sm]/He) and the associated thermal history models for 30 igneous samples from the Chatkal-Kurama terrane within Uzbekistan and Tajikistan (west of the Talas-Fergana Fault) and integrate our data with published data from the central Tian Shan (east of the Talas-Fergana Fault). The Chatkal-Kurama terrane experienced a phase of rapid cooling during the Triassic-Jurassic at ca. 225–190 Ma, which we interpret as a far-field response to the closure of the Palaeo-Asian Ocean or the accretion of the Qiangtang terrane on to the Eurasian margin. In the Late Jurassic to the Early Cretaceous, the Chatkal-Kurama terrane experienced a period of tectonic stability and denudation, before transitioning into a period of marine incursions of the Paratethys Sea. In contrast, fast cooling is recorded for the Kyrgyz central Tian Shan to the east of the Talas-Fergana Fault. The differing thermal histories at either side of the Talas-Fergana Fault suggest that the fault induced a topographic divide during the Late Jurassic-Early Cretaceous, with high relief in the east (Kyrgyz Tian Shan) and low relief to the west (Uzbek-Tajik Tian Shan). Finally, the Chatkal-Kurama terrane experienced renewed tectonic activity since ca. 30 Ma, related with the distant India-Eurasia collision and Pamir indentation. The Cenozoic reactivation induced crustal tilting of the Chatkal-Kurama terrane, progressively exposing deeper rocks to the southwest

Effects of anthropogenic habitat disturbance and Giardia duodenalis infection on a sentinel species' gut bacteria

Habitat disturbance, a common consequence of anthropogenic land use practices, creates human–animal interfaces where humans, wildlife, and domestic species can interact. These altered habitats can influence host–microbe dynamics, leading to potential downstream effects on host physiology and health. Here, we explored the effect of ecological overlap with humans and domestic species and infection with the protozoan parasite Giardia duodenalis on the bacteria of black and gold howler monkeys (Alouatta caraya), a key sentinel species, in northeastern Argentina. Fecal samples were screened for Giardia duodenalis infection using a nested PCR reaction, and the gut bacterial community was characterized using 16S rRNA gene amplicon sequencing. Habitat type was correlated with variation in A. caraya gut bacterial community composition but did not affect gut bacterial diversity. Giardia presence did not have a universal effect on A. caraya gut bacteria across habitats, perhaps due to the high infection prevalence across all habitats. However, some bacterial taxa were found to vary with Giardia infection. While A. caraya's behavioral plasticity and dietary flexibility allow them to exploit a range of habitat conditions, habitats are generally becoming more anthropogenically disturbed and, thus, less hospitable. Alterations in gut bacterial community dynamics are one possible indicator of negative health outcomes for A. caraya in these environments, since changes in host–microbe relationships due to stressors from habitat disturbance may lead to negative repercussions for host health. These dynamics are likely relevant for understanding organism responses to environmental change in other mammals.Fil: Kuthyar, Sahana. Northwestern University; Estados UnidosFil: Kowalewski, Miguel Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Biológica de Usos Múltiples (Sede Corrientes); Argentina. University of Emory; Estados UnidosFil: Roellig, Dawn. Centers For Disease Control And Prevention. National Center For Infectious Diseases; Estados UnidosFil: Mallot, Elizabeth K. Northwestern University; Estados UnidosFil: Zeng, Yan. Northwestern University; Estados UnidosFil: Gillespie, Thomas R. University of Emory; Estados UnidosFil: Amato, Katherine. Northwestern University; Estados Unido

Deep to shallow-marine sedimentology and impact of volcanism within the Middle Triassic Palaeo-Tethyan Semantan Basin, Singapore

The Middle Triassic Pulau Ayer Chawan Formation is a predominantly deep-marine, occasionally shallow-marine sedimentary succession, deposited in the Singapore sector of the Palaeo-Tethyan Semantan Basin. The formation provides an important record of the dynamic interplay between a siliciclastic sedimentary system and the products of an adjacent active volcanic arc. It is characterised by six sub-environments, including: deep-marine turbidite fan, deep-marine background sedimentation, subaqueous debris cone, shallow-marine, volcanically-sourced turbidite fan, and hyaloclastite mound or ridge. Turbidite fan deposits preserve the input of both siliciclastic and volcaniclastic sediments from the shelf, transported into the deep-marine environment by a suite of subaqueous sediment gravity flow processes, including: turbidity currents; mixed flow types (hybrid event beds); concentrated and hyper concentrated sediment gravity flows, and debris flows. Thick heterolithic successions of debrites were likely sourced through regular collapse of an unstable shelf. The presence of hybrid event beds, encountered within the deep-marine turbidite fans, supports a slope that was out-of-grade, and may have been actively retreating towards the hinterland. Together, these factors suggest regional-scale uplift of the eastern margins of the Semantan Basin during Triassic times, most likely facilitated through volcanic activity in the adjacent Palaeo-Tethys Sukhothai Arc. Evidence for contemporaneous, arc-related magmatism includes ubiquitous volcaniclastic sedimentary rocks within formation, including pyroclastic density current deposits and perhaps more-strikingly through the hyaloclastites of the Nanyang Member. The hyaloclastites formed through quenching of magmas delivered into the deep-marine setting from a series of sub-sea vents or mounds

Influence of wind-speed on short-duration NO2 measurements using Palmes and Ogawa passive diffusion samplers

We assessed the precision and accuracy of nitrogen dioxide (NO2) concentrations over 2-day, 3-day and 7-day exposure periods measured with the following types of passive diffusion samplers: standard (open) Palmes tubes; standard Ogawa samplers with commercially-prepared Ogawa absorbent pads (Ogawa[S]); and modified Ogawa samplers with absorbent-impregnated stainless steel meshes normally used in Palmes tubes (Ogawa[P]). We deployed these passive samplers close to the inlet of a chemiluminescence NO2 analyser at an urban background site in Glasgow, UK over 32 discrete measurement periods. Duplicate relative standard deviation was < 7% for all passive samplers. The Ogawa[P], Ogawa[S] and Palmes samplers explained 93%, 87% and 58% of temporal variation in analyser concentrations respectively. Uptake rates for Palmes and Ogawa[S] samplers were positively and linearly associated with wind-speed (P < 0.01 and P < 0.05 respectively). Computation of adjusted uptake rates using average wind-speed observed during each sampling period increased the variation in analyser concentrations explained by Palmes and Ogawa[S] estimates to 90% and 92% respectively, suggesting that measurements can be corrected for shortening of diffusion path lengths due to wind-speed to improve the accuracy of estimates of short-term NO2 exposure. Monitoring situations where it is difficult to reliably estimate wind-speed variations, e.g. across multiple sites with different unknown exposures to local winds, and personal exposure monitoring, are likely to benefit from protection of these sampling devices from the effects of wind, for example by use of a mesh or membrane across the open end. The uptake rate of Ogawa[P] samplers was not associated with wind-speed resulting in a high correlation between estimated concentrations and observed analyser concentrations. The use of Palmes meshes in Ogawa[P] samplers reduced the cost of sampler preparation and removed uncertainty associated with the unknown manufacturing process for the commercially-prepared collection pads