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The chapter presents a traditional model of partially defined predicates, its rejection of bivalence, and its responses to versions of the Sorites. An intractable problem with the model is then identified as arising from three assumptions: (i) the language containing the predicates is spoken by a vast but ill-defined community, (ii) the linguistic rules make fine-grained distinctions that go unnoticed by speakers, and (iii) the rules are abstracted from uses of the predicates. Progress, it is argued, requires dispensing with (i), embracing a plurality of micro-languages, and using them to construct perfected versions of (ii) and (iii). The resulting model defines the micro-language centered on an individual x at a time in terms of the dispositions of x to affirm or deny certain predicates of objects. Coordinated languages constructed from micro-languages centered on different individuals in a communicative situation allow one to assign assertive contents to uses of sentences. Given this, one can show how precise, knowable (though unknown) demarcations between items in the range of a vague predicate are determined. The technique, available to both defenders and opponents of excluded middle, can be used to reconstruct attractive responses to the Sorites, without some important defects.
Kernza® intermediate wheatgrass (Thinopyrum intermedium) is a novel perennial grain and forage crop with the potential to provide multiple ecosystem services, which recently became commercially available to farmers in the USA. The viability and further expansion of this promising crop require understanding how it may fit the needs of farmers’ livelihoods and the structure of their farming systems. However, no prior research has studied the perceptions and experiences of Kernza growers. The goals of this research were to understand why farmers grow Kernza, how Kernza fits into their systems and identify challenges for future research. We conducted in-depth interviews with ten growers in the North Central USA during the summer of 2017, who accounted for a third of the Kernza farmers in the USA at the time. All farmers had a positive attitude toward experimentation and trying new practices, and they were interested in Kernza for its simultaneous ecological and economic benefits. Kernza was marginal in terms of area, quality of fields and resources allocated in the farm systems, which also meant that farmers maintained low costs and risks. Growers utilized and valued Kernza as a dual-use crop (grain and forage), sometimes not harvesting grain but almost always grazing or harvesting hay and straw for bedding. Weeds were perceived as a challenge in some cases, but Kernza was valued as a highly weed-suppressive crop in others. Farmers requested information on optimal establishment practices, assessment of forage nutritive value, how to maintain grain yields over years, weed management, markets and economic assessment of Kernza systems. These results agree with other cases on sustainable practices adoption showing that engaging farmers in the research process from the beginning, identifying knowledge gaps and testing management alternatives are critical for the success and expansion of novel agricultural technologies.
The age of granophyric diorite from the Sosnowiec IG-1 borehole (Brunovistulia Terrane) was studied by means of U–Pb single-grain zircon analysis performed on a SHRIMP (sensitive high-resolution ion microprobe) IIe device. The isotope ages and provenance of zircons from the Emsian tuffs cropping out in the southern part of the Holy Cross Mountains (Małopolska Terrane) were also investigated using the same method. The age of the diorite intrusion (420 ± 2 Ma) is comparable with the combined Ar–Ar/magnetostratigraphic age of the Bardo diabase intrusion from the northern part of the Małopolska Terrane. These intrusions were emplaced during the same event of regional tectonic extension associated with the Rheic Ocean closure and the onset of processes creating the Rheno-Hecynian Basin near the Silurian/Devonian boundary. A negative Nb anomaly characteristic of both intrusions could be linked with the subduction of the Rheic oceanic crust under the SE margin of the Old Red Continent. Emsian magmatic activity in the distant Rheno-Hercynian Zone provided several tuff layers in the northern part of the Małopolska Terrane. As can be inferred from zircon ages, these tuffs were derived from mafic eruptions that cut sedimentary rocks containing detrital zircons transported from Baltica. This interpretation fits the existing models of development of the Rheno-Hercynian Basin in the Emsian.
Descartes believed the extended world did not terminate in a boundary: but why? After elucidating Descartes’s position in §1, suggesting his conception of the indefinite extension of the universe should be understood as actual but syncategorematic, we turn in §2 to his argument: any postulation of an outermost surface for the world will be self-defeating, because merely contemplating such a boundary will lead us to recognise the existence of further extension beyond it. In §3, we identify the fundamental assumption underlying this argument by comparing Descartes’s and Malebranche’s respective conceptions of the ontological status of modes of extension.
Producers are often faced with information from industry touting a generic return on investment of precision agriculture technologies that are inflated through the use of simple techniques that ignore the time value of money. The economics of precision technologies are as site-specific as the technology. Therefore, educating producers (and agribusiness) on how to determine the return on investment by following the correct investment analysis techniques within a proper decision-making framework helps ensure an accurate site-specific return on investment for precision agriculture technologies.
The Society of Precision Agriculture Australia Inc. (SPAA) is recognised as a leading, grower driven farming group in Australia. As an organisation it provides programs and services to its members and wider industry to promote the development and adoption of Precision Agriculture (PA) technologies as a means of enhancing the profitability and sustainability of agricultural production systems. This is achieved through publishing Australia’s only PA-dedicated magazine, delivering field days, seminars and conducting on-farm PA demonstrations and experiments. SPAA provides farmers with an independent source of advice on new concepts and equipment. The grains industry was the springboard for initial adoption, with winegrapes, horticulture and the sugar industry the focus sectors for further expansion. The purpose of this paper is to share the SPAA experience with a view to assisting the development of similar organisations in other countries
Tactics that target seedbanks are important components of weed management systems; however, such tactics can be difficult to adopt because consequences of seedbank reduction are often unclear. This study developed model-based software to provide insights on the economic outcomes, in the context of chile pepper production, of additions to tall morningglory seedbanks. Data for the model were derived from this and previous studies. In this study, field experiments were conducted to determine chile pepper yield and harvest efficiency responses to mid-season tall morningglory infestations. The experimental treatments were factorial combinations of herbicide (pendimethalin-treated, nontreated) and tall morningglory density (0, 4, 8, 12, 16, 20 plants 10-m row–1). Treatments were installed 9.5 weeks after crop seeding. Data collected included fresh weight of marketable chile peppers and time required for one individual to harvest 10-m of crop row, which was used to calculate the amount of chile pepper harvested in 1 min (harvest efficiency). Results indicated that crop yield was not influenced by tall morningglory density, pendimethalin treatment and interactions between tall morningglory density and pendimethalin. Harvest efficiency was influenced by tall morningglory density but was not influenced by herbicide treatment or interactions between herbicide treatment and tall morningglory density. Each additional tall morningglory plant decreased the amount of chile pepper harvested in 1 min by 9.7 g. The results of this and previous studies were used to develop model-based software that presents tall morningglory seedbank density effects on: (1) tall morningglory seedling densities after pendimethalin, (2) time requirements for hand-hoeing after pendimethalin, and (3) time requirements for hand-harvesting to acquire yield goals. The model-based software is intended to be used in the instruction of weed seedbank management strategies. By presenting seedbank density effects on weed control outcomes and crop production expenses, the model-based software might promote adoption of seedbank reduction strategies.
The Honggong pluton is the largest ferroan alkalic (A-type) granite intrusion emplaced along the Jiangshan–Shaoxing fault zone in southwestern Zhejiang Province, and has important implications for understanding the Late Mesozoic tectonic evolution of SE China. U–Pb ages of 138.7 ± 0.8, 134.2 ± 1.1, 128.5 ± 1.5 and 126.1 ± 0.9 Ma were obtained from zircon by laser ablation–inductively coupled plasma–mass spectrometry, indicating that the Honggong pluton formed in the Early Cretaceous. The Honggong pluton has a clear ferroan alkalic (A-type) granite geochemical signature with, for example, high total alkali contents and FeOt/(FeOt + MgO) values. The Sr–Nd–Hf isotopic compositions suggest that there was juvenile material in the magma source. Geochemical evidence indicates that the pluton was derived through extensive fractionation of melts that contained both asthenospheric mantle and Mesoproterozoic crustal components. These rare granites in southern China were emplaced during five episodes at 235–225, 190, 165–155, 100–90 and 140–120 Ma. The age of the Honggong pluton suggests that localized extension in southwestern Zhejiang Province began as early as ~138 Ma and continued to 126 Ma. This Early Cretaceous extensional event was triggered by localized rollback of the subducting Pacific Plate.
Organic agriculture continues to expand in the USA and in the European Union (EU), particularly in Italy, which had 48,650 organic farms in 2014 compared with 19,474 in the USA. Additionally, EU support for organic research is nearly double than that of the USA. Along with increased support for organic research, the EU organic community has achieved recognition at the European Commission policy level for a dedicated innovation platform, advocating the practice of farmer-first models for participatory research. The US land-grant universities have a long history of on-farm research, primarily through the Extension Service, but the need exists for more inclusive, second-loop, co-research with organic farmers. A survey was conducted of organic farmers and researchers in Italy and in the USA to ascertain the extent of participatory organic research activities and experiences, and explore the vision each group had for the future of co-innovation between organic farmers and researchers. Results indicated that, despite the higher level of organic research support in the EU, the percentage of researchers involved in on-farm/participatory organic research was equivalent in Italy and the USA, presumably due to the more recent emphasis in Italian/EU agricultural research agendas on the importance of farmer knowledge and participation in organic research. Overall, 60% of surveyed organic researchers in both countries cited involvement in on-farm/participatory organic research, with ‘farming systems’ and ‘nutrient/pest management’ the main research focus in the USA, compared with ‘farming systems’ and ‘equipment’ in Italy. Both countries’ researchers expressed their vision of participatory research as helping to improve communication between researchers and farmers, to enable work on relevant research, and to allow farmers to adapt technologies to their own conditions. Organic farmers in Italy completed survey questionnaires as part of a field day activity, leading to more Italian farmers responding to the survey, compared with USA counterparts who were queried via e-mail. Organic farmers in Italy identified ‘knowledge-sharing’ as a critical value of participatory research, and were conducting on-farm research with less compensation than US farmers. The ‘lack of time’ was cited as the most important constraint limiting participatory research by Italian and US farmers, although the ‘lack of common language’ also was rated as potentially impairing full participation. Lessons shared between EU and US organic researchers as a result of this project included methods to institute policies aimed at increasing support for organic research and co-innovations with organic farming communities, and connecting experienced on-farm researchers in the US with Italian colleagues to enhance collaborative activities with organic farmers.
with an approximate unit of projections, there is a smallest ideal
such that the quotient
is stably finite. In this paper a sufficient and necessary condition for an ideal of a
-algebra with real rank zero to be this smallest ideal is obtained by using
Annual losses of cocoa in Ghana from mirids are significant; therefore, accurate timing of insecticide application is critical to enhance yields. However, cocoa farmers often lack information on the expected mirid population for each season to enable them to optimize pesticide use. This study assessed farmers' knowledge and perceptions of mirid control and their willingness to use forecasting systems informing them of the expected mirid peaks and the time of pesticide application. A total of 280 farmers were interviewed in the Eastern and Ashanti regions of Ghana with a structured open- and closed-ended questionnaire. Most farmers (87%) considered mirids the most important insect pest on cocoa, with 47% of them attributing 30–40% of annual crop losses to mirid damage. There was a wide variation in the timing of insecticide application as a result of farmers using different sources of information to guide the start of application. The majority of farmers (56%) did not have access to information about the type, frequency and timing of insecticide use. However, respondents who were members of farmer groups had better access to such information. Extension officers were the preferred channel for information transfer to farmers, with 72% of farmers preferring them to other available methods of communication. Almost all the respondents (99%) saw the need for a comprehensive forecasting system to help farmers manage cocoa mirids. The importance of the accurate timing of mirid control based on forecasted information to farmer groups and extension officers is discussed.
RIM, or “Ryegrass Integrated Management,” is a model-based software allowing users to conveniently test and compare the long-term performance and profitability of numerous ryegrass control options used in Australian cropping systems. As a user-friendly decision support system that can be used by farmers, advisers, and industry professionals, RIM can aid the delivery of key recommendations among the agricultural community for broadacre cropping systems threatened by herbicide resistance. This paper provides advanced users and future developers with the keys to modify the latest version of RIM in order to facilitate future updates, modifications, and adaptations to other situations. The various components of RIM are mapped and explained, and the key principles underlying the construction of the model are explained. The implementation of RIM into a Microsoft Excel® software format is also documented, with details on how user inputs are coded and parameterized. An overview of the biological, agronomic, and economic components of the model is provided, with emphasis on the ryegrass biological characteristics most critical for its effective management. The extreme variability of these parameters and the subsequent limits of RIM are discussed. The necessary compromises were achieved by emphasizing the primary end-use of the program as a decision support system for farmers and advisors.
The stratigraphic succession exposed in the Karaburun area (southern Black Sea coast, NW Turkey) records multiple changes in depositional and tectonic settings during Cenozoic times. It starts with the Middle–Upper Eocene Soğucak Formation of reef limestone that across a normal fault, omitting the lower part of the Lower Oligocene Ceylan Formation (deep-marine shale unit), abuts the upper part of the Ceylan Formation that is made up of two facies: (1) shallow-marine sandstone and (2) shallow-marine limestone units containing horizons of submarine slumps. Both facies are unconformably overlain by the fluvial Upper Miocene Çukurçeşme Formation. The tectonic record includes: (1) latest Eocene – Early Oligocene NE–SW extension, (2) Early Oligocene NE–SW shortening and (3) Late Miocene NW–NE extension. The earliest normal faults cutting the Soğucak and the lower part of the Ceylan formations are associated with clastic dykes injected into the deep-marine shale. These structures suggest a disruption of the Eocene carbonate platform and are also known in the neighbouring Thrace Basin. The following NE–SW shortening created the NE-vergent Karaburun Thrust that is synchronous with the shallowing and inversion of the Ceylan Basin. Rotation of the stress field is recorded by changes in clastic dyke orientation and their deformation. Compression caused multiple westerly directed submarines slides from uplifts in easterly located regions. This event is not recorded in the Thrace Basin. Finally, the Miocene tectonic activity formed NW- and NE-striking normal faults. The outlined tectonic history includes Early Oligocene extensional and compressional episodes recorded in the southern margin of the Black Sea that had hitherto not been known.
Although being the main bottlenecks for commercial poultry development in Togo,
feeding and management practices retain little attention. Indeed, there is no
proficient feed miller unit which can provide high quality feed according to the
needs of the farmers. This is due to a lack of information on nutrition and
relevant management tools or people trained as poultry farm managers. With the
aim to alleviate poverty and hunger in Togo, an inter-university project
[Catholic University of Leuven (KUL) and University of Lome (UL)] as a model for
poultry development was being run from June 2006 to May 2012. Specific
objectives of the project are 1) to provide insights and disseminate guidelines
and information on adapted methods to improve poultry production and 2) to focus
on development of new technologies in poultry production and implementation of
research on better poultry nutrition, feeding and management practices.
In 2005, the existence of glyphosate-resistance in Palmer amaranth was
confirmed at a single 250 ha field site in Macon County, Georgia. Currently,
all cotton producing counties in Georgia are infested, to some degree, with
glyphosate-resistant Palmer amaranth. In 2010 and 2011, surveys were
administered to Georgia growers and extension agents to determine how the
development of glyphosate-resistance has affected weed management in cotton.
According to respondents, the numbers of cotton acres that were treated with
paraquat, glufosinate and residual herbicides effective against Palmer
amaranth more than doubled between 2000 to 2005 and 2006 to 2010. Glyphosate
use declined between 2000 to 2005 and 2006 to 2010 although, on average, the
active ingredient was still applied to a majority of cotton acres. Although
grower herbicide input costs have more than doubled following the evolution
and spread of glyphosate resistance, chemically-based control of Palmer
amaranth is still not adequate. As a consequence, Georgia cotton growers
hand weeded 52% of the crop at an average cost of $57 per hand-weeded ha;
this represents a cost increase of at least 475% as compared to the years
prior to resistance. In addition to increased herbicide use and hand
weeding, growers in Georgia are also using mechanical, in-crop cultivation
(44% of acres), tillage for the incorporation of preplant herbicides (20% of
the acres), and post-harvest deep-turning (19% of the acres every three
years) for weed control. Current weed management systems are more diverse,
complex and expensive than those employed only a decade ago, but are
effective at controlling glyphosate-resistant Palmer amaranth in
glyphosate-resistant cotton. The success of these programs may be related to
producers improved knowledge about herbicide resistance, and the biological
attributes that make Palmer amaranth so challenging, as well as their
ability to implement their management programs in a timely manner.
Numerous specimens of Ophistognathus panamaensis were observed along the coast of Oaxaca in western Mexico and one specimen was collected by Hawaiian sling in the coral reef zones of Huatulco, Mexico in November 2012. Therefore, this paper reports for the first time the occurrence of O. panamaensis in Mexico and extends its previous distribution by 1245 km north of the Eastern Pacific equatorial zone.
Using the Dadarlat isomorphism, we give a characterization for the Kasparov product of
-algebra extensions. A certain relation between
$KK\left( A,\,Q\left( B \right) \right)$
$KK\left( A,\,Q\left( KB \right) \right)$
is also considered when
is not stable, and it is proved that
$KK\left( A,\,Q\left( B \right) \right)$
$KK\left( A,\,Q\left( KB \right) \right)$
are not isomorphic in general.
Cost-effective extension strategies are needed to promote widespread adoption of agricultural technologies in developing countries. Integrated pest management (IPM) practices, for example, can offer economic, health, and environmental benefits but remain largely underused. This study evaluates the current IPM dissemination program implemented by the Bangladesh Department of Agricultural Extension and uses a linear programming model to examine alternative strategies to improve IPM adoption. Results suggest that technology transfer programs may increase their impact by reallocating funding from intensive but costly interpersonal communication methods (i.e., farmer field schools) to less intensive methods (i.e., mass media and field days) that reach broader audiences.
The Eleonore Bay Supergroup (EBG) is a 16 km-thick shallow-water sequence of Neoproterozoic age that is preserved within the East Greenland Caledonides in several tracts, surrounded by crystalline gneisses and schistose supracrustal rocks. The apparent downward transition from non-metamorphic EBG into gneiss gave rise to the classic ‘stockwerke’ hypothesis, in which all the metamorphism was regarded as Caledonian, and differences in grade were ascribed to the ascent of a migmatite front to different levels within the orogen. Field and isotopic studies in the 1970s however revealed that the underlying gneisses and schists had undergone orogenic reworking in mid-Proterozoic time; the EBG–basement contact was then interpreted as an approximately bedding-parallel décollement with apparent lag geometry, that is with EBG cover rocks in its hangingwall.
Recent work in the northernmost EBG tract, at Ardencaple Fjord, has shed light on the problems posed by the basal relationships of the EBG, and together with regional structural and stratigraphic data leads to the following interpretation. There are two regionally important basement-cover interfaces within the East Greenland Caledonides. The earlier one is between Archaean/early Proterozoic gneisses and early Proterozoic supracrustal rocks, which were pervasively deformed in mid-Proterozoic time and form the basement to the Neoproterozoic Eleonore Bay cover sequence. This was deposited on a vast, continually subsiding shelf that is now preserved in East and NE Greenland and Svalbard, and contains Grenville detritus. EBG deposition was terminated by major extensional faulting of Vendian age; the succeeding Tillite Group is interpreted as a syn-rift sequence, presumably associated with the opening of Iapetus.
The EBG–basement contacts that are not late faults are inferred to be extensional shear zones of Vendian age. These were reactivated in compression during the Caledonian orogeny in the Silurian, with metamorphic and fabric convergence, which accounts for the apparent downward transition from sedimentary rocks through schists into gneisses. Caledonian shortening was not large; inversion of the Vendian grabens was incomplete, so that the marginal shear zones retained their lag geometry and large tracts of low grade Eleonore Bay sediments are preserved at the present erosion level, surrounded by Proterozoic basement rocks, within the Caledonian belt of East Greenland.