scholarly journals Supplemental Material: Uneven spatial sampling distorts reconstructions of Phanerozoic seawater temperature

2021 ◽  
Author(s):  
Lewis A. Jones ◽  
Kilian Eichenseer
Keyword(s):  
Seawater Temperature ◽  
Spatial Sampling ◽  
Data Preparation ◽  
Additional Information ◽  
Analysis And Study

Additional information regarding data preparation, analysis, and study limitations.<br>

scholarly journals Supplemental Material: Uneven spatial sampling distorts reconstructions of Phanerozoic seawater temperature

2021 ◽  
Author(s):  
Lewis A. Jones ◽  
Kilian Eichenseer
Keyword(s):  
Seawater Temperature ◽  
Spatial Sampling ◽  
Data Preparation ◽  
Additional Information ◽  
Analysis And Study

Additional information regarding data preparation, analysis, and study limitations.<br>

Economic optimisation of soil testing on commercial farms: space, time and variables

2021 ◽  
Author(s):  
Taro Takahashi
Keyword(s):  
Concave Function ◽  
Information Value ◽  
Spatial Sampling ◽  
Soil Testing ◽  
Biological Interactions ◽  
Additional Information ◽  
The North ◽  
Incremental Value ◽  
Commercial Farms ◽  
The Uk

&lt;p&gt;A holistic evaluation of agricultural systems requires mechanistic understanding of physical, chemical and biological interactions both aboveground and belowground, yet obtaining this information on commercial farms is a challenging task. In order to support practical decision making by commercial producers, it is therefore necessary to identify system-wide performance indicators that are observable presently and cost-effectively. Data acquired through commercial soil testing satisfy these conditions; however, the relationship between the density of information &amp;#8212; thus the cost of testing &amp;#8212; and the value of information as a guideline for on-farm managerial changes is not well-understood.&lt;/p&gt;&lt;p&gt;Using high-resolution soil data from the North Wyke Farm Platform in the UK as a case exemplar, this solicited talk discusses theoretical and computational frameworks to quantify the value of an information package defined by soil testing strategies. A bootstrapping experiment revealed that the information value is often a concave function of the spatial sampling frequency, indicating that &amp;#8220;half-hearted&amp;#8221; soil data are unlikely to be able to inform optimal farm management. On the other hand, a high degree of serial correlation as well as atemporal inter-variable correlation resulted in some measurements identified as being redundant, as the incremental value of additional information was often found to be small and occasionally negative. Given the time and budgetary constraints, therefore, it is suggested that more effort should be spent on snapshot spatial sampling of a small number of variables, rather than continuous spot sampling of a large number of variables.&lt;/p&gt;

scholarly journals Uneven spatial sampling distorts reconstructions of Phanerozoic seawater temperature

Geology ◽  
2021 ◽  
Author(s):  
Lewis A. Jones ◽  
Kilian Eichenseer
Keyword(s):  
Spatial Distribution ◽  
Global Climate ◽  
Seawater Temperature ◽  
Spatial Sampling ◽  
Deep Time ◽  
Proxy Records ◽  
Spatial Coverage ◽  
Reconstructed Temperature ◽  
Gradient Based ◽  
Cooling Trend

Paleotemperature proxy records are widely used to reconstruct the global climate throughout the Phanerozoic and to test macroevolutionary hypotheses. However, the spatial distribution of these records varies through time. This is problematic because heat is unevenly distributed across Earth’s surface. Consequently, heterogeneous spatial sampling of proxy data has the potential to bias reconstructed temperature curves. We evaluated the spatiotemporal evolution of sampling using a compilation of Phanerozoic δ18O data. We tested the influence of variable spatial coverage on global estimates of paleotemperature by sampling a steep “modern-type” latitudinal temperature gradient and a flattened “Eocene-type” gradient, based on the spatial distribution of δ18O samples. We show that global paleotemperature is overestimated in ~70% of Phanerozoic stages. Perceived climatic trends for some intervals might be artifactually induced by shifts in paleolatitudinal sampling, with equatorward shifts in sampling concurring with warming trends, and poleward shifts concurring with cooling trends. Yet, the magnitude of some climatic perturbations might also be underestimated. For example, the observed Ordovician cooling trend may be underestimated due to an equatorward shift in sampling. Our findings suggest that while proxy records are vital for reconstructing Earth’s paleotemperature in deep time, consideration of the spatial nature of these data is crucial to improving these reconstructions.

Production of New and Revised A.A.V.S.O. Charts

1979 ◽  
Vol 46 ◽  
pp. 368
Author(s):  
Clinton B. Ford
Keyword(s):  
Variable Star ◽  
Standard Form ◽  
Original Data ◽  
University Of Pennsylvania ◽  
Standard Format ◽  
Additional Information ◽  
The Gift ◽  
The University

A “new charts program” for the Americal Association of Variable Star Observers was instigated in 1966 via the gift to the Association of the complete variable star observing records, charts, photographs, etc. of the late Prof. Charles P. Olivier of the University of Pennsylvania (USA). Adequate material covering about 60 variables, not previously charted by the AAVSO, was included in this original data, and was suitably charted in reproducible standard format.Since 1966, much additional information has been assembled from other sources, three Catalogs have been issued which list the new or revised charts produced, and which specify how copies of same may be obtained. The latest such Catalog is dated June 1978, and lists 670 different charts covering a total of 611 variables none of which was charted in reproducible standard form previous to 1966.

Convergent Beam Electron Diffraction

1978 ◽  
Vol 36 (3) ◽  
pp. 304-315
Author(s):  
G. Lehmpfuhl
Keyword(s):  
Electron Diffraction ◽  
Diffraction Pattern ◽  
Crystal Surface ◽  
Diffraction Spot ◽  
Crystal Thickness ◽  
Large Area ◽  
Electron Microscopic ◽  
Additional Information ◽  
Microscopic Investigations

Introduction In electron microscopic investigations of crystalline specimens the direct observation of the electron diffraction pattern gives additional information about the specimen. The quality of this information depends on the quality of the crystals or the crystal area contributing to the diffraction pattern. By selected area diffraction in a conventional electron microscope, specimen areas as small as 1 µ in diameter can be investigated. It is well known that crystal areas of that size which must be thin enough (in the order of 1000 Å) for electron microscopic investigations are normally somewhat distorted by bending, or they are not homogeneous. Furthermore, the crystal surface is not well defined over such a large area. These are facts which cause reduction of information in the diffraction pattern. The intensity of a diffraction spot, for example, depends on the crystal thickness. If the thickness is not uniform over the investigated area, one observes an averaged intensity, so that the intensity distribution in the diffraction pattern cannot be used for an analysis unless additional information is available.

Microtubule nucleation sequence studied by time-resolved x-ray scattering and electron microscopy

1983 ◽  
Vol 41 ◽  
pp. 766-767
Author(s):  
Eva-Maria Mandelkow ◽  
Eckhard Mandelkow ◽  
Joan Bordas
Keyword(s):  
Electron Microscopy ◽  
Dynamic Equilibrium ◽  
Time Resolved ◽  
X Ray ◽  
Additional Information ◽  
X Ray Scattering ◽  
Low Concentrations ◽  
Microtubule Growth ◽  
Ray Patterns ◽  
Ray Scattering

When a solution of microtubule protein is changed from non-polymerising to polymerising conditions (e.g. by temperature jump or mixing with GTP) there is a series of structural transitions preceding microtubule growth. These have been detected by time-resolved X-ray scattering using synchrotron radiation, and they may be classified into pre-nucleation and nucleation events. X-ray patterns are good indicators for the average behavior of the particles in solution, but they are difficult to interpret unless additional information on their structure is available. We therefore studied the assembly process by electron microscopy under conditions approaching those of the X-ray experiment. There are two difficulties in the EM approach: One is that the particles important for assembly are usually small and not very regular and therefore tend to be overlooked. Secondly EM specimens require low concentrations which favor disassembly of the particles one wants to observe since there is a dynamic equilibrium between polymers and subunits.

Edge Penetration Effects in the Low-Loss Electron Image in the SEM

1988 ◽  
Vol 46 ◽  
pp. 202-203
Author(s):  
Oliver C. Wells
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Beam Energy ◽  
Secondary Electron ◽  
Sharp Edge ◽  
Beam Diameter ◽  
Low Loss ◽  
Additional Information ◽  
Electron Image ◽  
Scanning Electron

The low-loss electron (LLE) image in the scanning electron microscope (SEM) is useful for the study of uncoated photoresist and some other poorly conducting specimens because it is less sensitive to specimen charging than is the secondary electron (SE) image. A second advantage can arise from a significant reduction in the width of the “penetration fringe” close to a sharp edge. Although both of these problems can also be solved by operating with a beam energy of about 1 keV, the LLE image has the advantage that it permits the use of a higher beam energy and therefore (for a given SEM) a smaller beam diameter. It is an additional attraction of the LLE image that it can be obtained simultaneously with the SE image, and this gives additional information in many cases. This paper shows the reduction in penetration effects given by the use of the LLE image.

Questions and Answers

2000 ◽  
Vol 5 (2) ◽  
pp. 3-3
Author(s):  
Christopher R. Brigham ◽  
James B. Talmage
Keyword(s):  
Nervous System ◽  
Peripheral Nervous System ◽  
Spinal Nerve ◽  
Sensory Loss ◽  
Residual Symptoms ◽  
Additional Information ◽  
Questions And Answers ◽  
Motor Nerves ◽  
Symptoms And Signs ◽  
Limited Motion

Abstract Lesions of the peripheral nervous system (PNS), whether due to injury or illness, commonly result in residual symptoms and signs and, hence, permanent impairment. The AMA Guides to the Evaluation of Permanent Impairment (AMA Guides) describes procedures for rating upper extremity neural deficits in Chapter 3, The Musculoskeletal System, section 3.1k; Chapter 4, The Nervous System, section 4.4 provides additional information and an example. The AMA Guides also divides PNS deficits into sensory and motor and includes pain within the former. The impairment estimates take into account typical manifestations such as limited motion, atrophy, and reflex, trophic, and vasomotor deficits. Lesions of the peripheral nervous system may result in diminished sensation (anesthesia or hypesthesia), abnormal sensation (dysesthesia or paresthesia), or increased sensation (hyperesthesia). Lesions of motor nerves can result in weakness or paralysis of the muscles innervated. Spinal nerve deficits are identified by sensory loss or pain in the dermatome or weakness in the myotome supplied. The steps in estimating brachial plexus impairment are similar to those for spinal and peripheral nerves. Evaluators should take care not to rate the same impairment twice, eg, rating weakness resulting from a peripheral nerve injury and the joss of joint motion due to that weakness.

Markers of arterial stiffness in peripheral arterial disease

VASA ◽  
2015 ◽  
Vol 44 (5) ◽  
pp. 341-348 ◽  
Author(s):  
Marc Husmann ◽  
Vincenzo Jacomella ◽  
Christoph Thalhammer ◽  
Beatrice R. Amann-Vesti
Keyword(s):  
Arterial Stiffness ◽  
Peripheral Arterial Disease ◽  
Pulse Wave ◽  
Augmentation Index ◽  
Arterial Disease ◽  
Care Physician ◽  
Additional Information ◽  
Non Invasive ◽  
Assessment Techniques ◽  
Peripheral Arterial

Abstract. Increased arterial stiffness results from reduced elasticity of the arterial wall and is an independent predictor for cardiovascular risk. The gold standard for assessment of arterial stiffness is the carotid-femoral pulse wave velocity. Other parameters such as central aortic pulse pressure and aortic augmentation index are indirect, surrogate markers of arterial stiffness, but provide additional information on the characteristics of wave reflection. Peripheral arterial disease (PAD) is characterised by its association with systolic hypertension, increased arterial stiffness, disturbed wave reflexion and prognosis depending on ankle-brachial pressure index. This review summarises the physiology of pulse wave propagation and reflection and its changes due to aging and atherosclerosis. We discuss different non-invasive assessment techniques and highlight the importance of the understanding of arterial pulse wave analysis for each vascular specialist and primary care physician alike in the context of PAD.

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