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This paper reports on a project conducted with representatives of indigenous Māori organizations that are active in New Zealand land-based sectors. The primary aim of the research was to assist these organizations in thinking about their current and future positioning with regard to climate change. Using Peter Checkland’s Soft Systems Methodology as a broad framework for the research, the paper first seeks to capture some of the likely issues that enable and constrain strategic activity in the climate change arena. It then uses various soft systems modelling tools to research and structure a debate to consider the desirability and feasibility of particular interventions.
The Einstein IPC observed the bright (5 mCrab) X-ray emitting BL Lac Object PKS 2155-304 on 1979 November 4th and 5th through 7th and on 1980 May 16th through 18th. A total of 17.4 hours were spent monitoring the source. Changes in intensity of between 10–50% are evident in the data for time scales of days and months. The source was constant to within 10% of the mean intensity on hourly time scales for all intervals of data except one. Repeated factor of 2 variations in intensity, occuring on 10–30 second time scales, were observed during the first 50 minutes of the 1979 Nov. 5th observation. These variations, however, were anticorrelated with variations seen in an adjacent background region. Concurrent MPC observations also failed to confirm the rapid changes, although they should have been readily detected. Thus, we conclude that the observed rapid variations are not intrinsic to the source, but originated in the IPC. These results can have implications for other IPC reports of short time scale variability for active galaxies and for source models based on such observations.
Most paleontological textbooks deal with tracheates and chelicerates in only a cursory way because of their putatively poor fossil record. However, recent investigations into the paleobiology of these groups reveal that the fossil record is not only more extensive than previously assumed, but provides a wealth of information regarding both broad and detailed patterns of evolution of the two most diverse subphyla on the planet. Tracheata, including insects, entognaths and the various myriapod groups, are the most diverse subphylum. Insects alone are the most diverse class of animals known, outnumbering the combined species level diversity of all other animals. The Chelicerata, composed of the eurypterids, xiphosurids, arachnids and pycnogonids, are the second most diverse subphylum, with the diversity of arachnids exceeding all classes except for the insects. Consequently, not only does the evolution of tracheates and chelicerates provide an interesting story in itself, but these groups also provide us with insight into more general aspects of the evolutionary process that are of interest to the general evolutionary biologist as well as to the arthropod specialist.
Since the late Paleozoic, insects and arachnids have diversified in the terrestrial world so spectacularly that they have become unquestionably the most diverse group of organisms to ever inhabit the planet. In fact, this 300 million year interval may appropriately be referred to as the age of arthropods. What is the origin and history of terrestrial arthropods? How is arthropod diversity maintained on land? In this rhetorical context we will discuss (1) the degree to which terrestriality is found in arthropods, (2) the physiological barriers to terrestrialization that arthropod clades confronted, (3) the historical record of arthropod diversity on land based on paleobiological, comparative physiological and zoogeographical evidence, and (4) some tentative answers to the “why” of terrestrial arthropod success. We are providing a geochronologic scope to terrestriality that includes not only the early history of terrestrial arthropods, but also the subsequent expansion of arthropods into major terrestrial habitats.
Polymer nanocomposites (PNC) include a copolymer or polymer which has nanoparticles dispersed in the polymer matrix at the nano-level. One of the most common types of polymer nanocomposites contain smectic clays as the nanoparticles. These clay minerals increase the mechanical properties of standard polymers and improve barrier properties. For optimum barrier properties, Layer-by-Layer assembly (LbL) is one of the most effective methods for depositing thin films. LbL methods however, are quite tedious and produce large quantities of waste. A newly discovered phenomenon of self-assembled polymer nanocomposites utilizes entropic forces to drive the assembly to spontaneously form a larger nanostructured film. This approach allows polymers and nanoparticles with high particle loadings to be mixed, and create the super gas barrier films. We have developed a coating technique which can be employed to make self-assembled gas barrier films via inkjet printing. This technique is industrially scalable and efficient. This is because it does not need any rinsing step and drying steps as required in LbL. The influence of different polymers Polyvinylpyrrolidone (PVP) and Poly (acrylic acid) PAA with Montmorillonite (MMT) nanoclay solutions on Polyethylene terephthalate (PET) substrate is examined to study their effectiveness as a gas barrier film. The results showing the excellent oxygen barrier behavior of a combination of PVP and MMT Nano clay nanocomposite with high transparency. These high barrier gas nanocomposite films are good candidates for a variety of food packaging applications.
Since the discovery of glass-ceramics by Stookey in the 1950s, there has been increasing demand for glass-ceramics with high strength and toughness for medical, structural, and consumer electronics markets. This article reviews recent developments in composition, microstructure, and mechanical properties of glass-ceramics, with an emphasis on their mechanical performance. It reveals that glass-ceramics with strength and toughness comparable to structural ceramics, such as Al2O3, have been successfully developed. Meanwhile, efforts are being devoted to creating glass-ceramics with further improved damage resistance. With inspiration from natural materials such as jade, baddeleyite, bone, and nacre, glass-ceramics with unique microstructures and properties have been obtained. Further progress is needed in the design of novel compositions, microstructures, and phase assemblages to activate multiple toughening mechanisms in glass-ceramics for significant improvements in strength and toughness.
Carbonate intercalated Mg-Al layered double hydroxides (Mg-Al-CO3-LDH) were successfully produced by mechanical alloying process using different starting raw chemicals. Two distinct chemical reactions were activated at different milling times. The samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), and transmission electron microscopy (TEM). Results revealed that the structural characteristics of Mg-Al-CO3-LDH such as lattice parameters, unit cell volume, and the interlayer spacing were affected strongly by milling time. Based on the XRD data, the formation rate of pure Hydrotalcite (HT) was strongly influenced by the chemical composition of raw materials. Electron microscopic observation displayed that the final product had a platelet-like structure with an average particle size of 20-100 nm. Therefore, the synthesis of Mg-Al-CO3-LDH via a cost-effective solid-state method owing to simplicity and reproducibility can be a promising candidate especially for use in biomaterials and catalyst industries.
Objectives: Connectionist theories of brain function took hold with the seminal contributions of Norman Geschwind a half century ago. Modern neuroimaging techniques have expanded the scientific interest in the study of brain connectivity to include the intact as well as disordered brain. Methods: In this review, we describe the most common techniques used to measure functional and structural connectivity, including resting state functional MRI, diffusion MRI, and electroencephalography and magnetoencephalography coherence. We also review the most common analytical approaches used for examining brain interconnectivity associated with these various imaging methods. Results: This review presents a critical analysis of the assumptions, as well as methodological limitations, of each imaging and analysis approach. Conclusions: The overall goal of this review is to provide the reader with an introduction to evaluating the scientific methods underlying investigations that probe the human connectome. (JINS, 2016, 22, 105–119)
Most researchers today are bombarded with spam email solicitations from questionable scholarly publishers. These emails solicit article manuscripts, editorial board service, and even ad hoc peer reviews. These “predatory” publishers exploit the scholarly publishing process, patterning themselves after legitimate scholarly publishers yet performing little or no peer review and quickly accepting submitted manuscripts and collecting fees from submitting authors. These counterfeit publishers and journals have published much junk science? especially in the field of cosmology? threatening the integrity of the academic record. This paper examines the current state of predatory publishing and advises researchers how to navigate scholarly publishing to best avoid predatory publishers and other scholarly publishing-related perils.
A transcendental philosophy as described and practiced by Kant is itself a logic. It is not intended to decide such factual questions as whether there is a God or humans are free, but to address semantical issues like what the meaning of God or freedom is. Within the semantical space where the (transcendental) logical enterprise is located, one can take different words as primitives and establish a network of semantical relations and dependencies based on those primitives. A logic is a self-organizing structure, self-enclosed and self-referential, that provides the bare scaffolding of a world and, if given enough data, even a large part of its actual construction. Logic is a highly ambitious theory: one that attempts to construct a universal language. In and by itself, this theory will be found persuasive only by those who are already committed to the particular view it expresses and articulates.
I believe that, for reasons elaborated elsewhere (Beall, 2009; Priest, 2006a, 2006b), the logic LP (Asenjo, 1966; Asenjo & Tamburino, 1975; Priest, 1979) is roughly right as far as logic goes.1 But logic cannot go everywhere; we need to provide nonlogical axioms to specify our (axiomatic) theories. This is uncontroversial, but it has also been the source of discomfort for LP-based theorists, particularly with respect to true mathematical theories which we take to be consistent. My example, throughout, is arithmetic; but the more general case is also considered.
This paper is a sequel to Beall (2011), in which I both give and discuss the philosophical import of a ‘classical collapse’ result for the propositional (multiple-conclusion) logic LP+. Feedback on such ideas prompted a spelling out of the first-order case. My aim in this paper is to do just that: namely, explicitly record the first-order result(s), including the collapse results for K3+ and FDE+.
Human pregnancies contain large amounts of water in several compartments, including the fetal body, the placenta and membranes, and the amniotic fluid (AF). This chapter reviews the current understanding of water flow into the gestation and into and out of the amniotic cavity. It reviews evidence suggesting that the fetus may regulate the AF volume. Decreases in fetal urine flow are associated with a decrease in AF volume. The mature fetus can reduce urine flow to achieve homeostasis; in the near-term ovine fetus increased plasma osmolality is associated with fetal vasopressin secretion, urinary concentration, and reduced urine flow. Water permeability in the placenta appears to be regulated at the level of the syncytiotrophoblast, and to vary with gestational age. A variety of influences can alter AF volume by affecting one of the factors associated with AF formation and resorption.
California Assembly Bill 1535 awarded $US 15 million to California public schools to promote, develop and sustain instructional school gardens through the California Instructional School Garden Program (CISGP). The present study was designed to assess the effectiveness of the CISGP at assisting schools in implementing, maintaining and sustaining an academic school garden programme, determine how schools utilized the funding they received and assess the impact of the California state budget crisis on the CISGP.
A mid-term evaluation was used to assess the degree to which schools achieved their instructional garden-related goals.
Only schools that applied for the CIGSP grant as part of a school district and also provided a contact email and had a unique contact person were included in the study (n 3103, 80·6 %).
In general, many schools reported not achieving their predicted goals with regard to the CISGP grant. Only 39·4 % of schools reported accomplishing all of their garden-related goals. Over one-third (37·8 %) of schools reported that their school gardens were negatively affected by the California budget deficit.
The difference between predicted and actual utilization of the CISGP grants may be due to a combination of the effects of budget shortfall and insufficiency of the grant award amount.
Potential of polymer–clay nanocomposites as barrier materials
Early in the development of polymer–clay nanocomposites it was recognized that, due to the platy morphology of the smectic nanoparticles, the gas permeability of the composite would be altered considerably from that of the pure polymer. This improved barrier has major applications potential in the food and pharmaceutical industries. These composites have the additional advantage of maintaining clarity of display of packaged foods or medicines. The fundamental origin of the barrier properties exhibited by polymer–clay nanocomposites appears to derive largely from the physical morphology of the nanocomposites, but in some notable cases, this cannot be explained by the physical barrier of the nanoparticles.
The number and types of applications utilizing the barrier properties of polymer–clay nanocomposites are significant. In general terms the majority of applications involve the protection of food or drugs from the ingress of either oxygen or water vapor. In the area of flexible food packaging, the nanocomposites will not only protect the food from spoilage and improve shelf life, but also should allow down-gauging in applications where the existing packaging barrier is sufficient. Because of the size and refractive index of the clay nanoparticles, the packaging will also be transparent.
An early observation by Blumstein  indicated that montmorillonite present in the polymerization of methyl methacrylate to produce polymer–clay composites significantly increased the thermal stability of the methyl methacrylate polymer in relation to polymethyl methacrylate prepared without the montmorillonite present. The polymer within the galleries of the montmorillonite was reported to have significantly higher thermal stability. Speculation on the cause of this enhanced thermal stability focused on restricted polymer chain mobility in the galleries and the prevention of oxygen diffusion into the galleries. The presence of oxygen during the thermal degradation of polymer–clay nanocomposites will be demonstrated to be a significant independent variable relating to the thermal degradation.
Little further activity is found in the literature until the advent of the importance of exfoliated layered clays in the dramatic enhancement of polymer mechanical performance at low concentrations was reported . Subsequent systematic evaluations of the thermal stability of polymer–clay nanocomposites were initiated by Jeff Gilman's group at NIST and Emmanuel Giannelis' group at Cornell, with remarkable results. This work led to a dramatic increase in scientific investigations focused on the structure–property relationships of polymer–clay nanocomposites to thermal stability and flame retardancy.
An excellent review of the work on the flame retardancy of polymer nanocomposites was published in 2007 . This chapter will focus on the evaluation of the proposed mechanisms for enhanced thermal stability of polymer–clay nanocomposites, the proposed relationships between enhanced thermal stability of polymer–clay nanocomposites and flame retardancy, and the synergies that develop between traditional flame retardants for polymers and polymer–clay nanocomposites.
Can one imagine the utility of a dispersed-phase reinforcement for polymers that has a thickness of 1 nm, a platelike morphology with minimal dimensions of 150 to 200 nm, robust with a modulus of 180 GPa, nontoxic (FDA classification of GRAS; generally regarded as safe for a majority of applications), a surface area in excess of 750 m2/g, a charge suitable for altering its hydrophobic–hydrophilic balance at will, and a refractive index similar to polymer so that the nanoparticles will appear transparent in the polymer composite? How difficult would it be to prepare such a particle?
This particle is naturally occurring and found around the world. It is easily mined and purified. The reactor for the particle was a volcano. The ash from many volcanoes was spread around the earth during an intense period of activity many millions of years ago. This ash was transformed into clay (montmorillonoids or smectites) by natural processes, into uncharged species (talc and pyrophyllite) and charged species through isomorphic substitution of the crystal structure (hectorite, montmorillonite, saponite, suconite, volchonskoite, vermiculite, and nontronite).
Montmorillonite serves as the principle mineral for the development of polymer–clay nanocomposites discussed in this book. A misunderstanding of the terms bentonite (the ore or rock) and montmorillonite (the mineral) are pervasive in the literature. We will focus on utilizing the mineral name. The composition of montmorillonite can be described by imagining a sandwich structure with the top and bottom layers composed of silica dioxide tetrahedral structures.