Production Apparatus Research Articles

Star Trek at 50, or, Star Trek beyond Star Trek

Star Trek Beyond (Lin US 2016) features (yet again) the apparent destruction of the USS Enterprise, this time at the hands of a swarm of tiny insect-like metallic drones ploughing through its hull. It is a familiar scene. The Enterprise is beaten within an inch of its life in Star Trek II: The Wrath of Khan (Meyer US 1982) - costing Spock (Leonard Nimoy) his life in the process - and is then destroyed for real in Star Trek III: The Search for Spock (Nimoy US 1984). A new Enterprise-B is practically totalled on its maiden voyage in Star Trek: Generations (Carson US 1994), a film that ends with The Next Generations (US 1987-94) beloved Enterprise-D crashing into a planet and being permanently scuttled (and in the meantime drops a bridge on Captain Kirk (William Shatner)). By that point we had already seen the explosive end of the Enterprise-C, too, in a famous episode ('Yesterday's Enterprise' (19 Feb 1990)) whose time-travel mechanics innovated a way to kill off Tasha Yar (Denise Crosby) a second time. The Enterprise-E manages to survive the TNG film franchise, but Data (Brent Spiner) does not. Captain Sisko (Avery Brooks) more or less dies at the end of Deep Space Nine (US 1993-9), a series that had already killed off series regular Jadzia Dax (Terry Farrell) while plunging the once-peaceful, once-utopian Federation into a cataclysmic, brutal war with the authoritarian Dominion. Voyager (US 1995-2001) killed off all of its principal characters multiple times in alternate timelines and other dimensions, especially Harry Kim (Garrett Wang) - and on at least two separate occasions ('Deadlock' (18 Mar 1996) and 'Course: Oblivion' (3 Mar 1999)) pseudoscientifically generated exact duplicates of the entire USS Voyager ship and crew specifically for the purpose of killing them all by the end of the episode. And the course of the prequel series Enterprise (US 2001-5) kills not just series regular Chief Engineer 'Trip' Tucker (Connor Trineer), but millions of citizens of 2153-era Florida to boot.After Enterprise-the-series died (and with it the entire TNG-era production apparatus of Star Trek) the whole Prime Universe did - abandoned to the also-ran status of tie-in novels, comics and games, while the film property moved on to a 'reboot' timeline with younger versions of The Original Series (US 1966-9) actors. The new film universe begins by killing off the Romulus-Remus double planetary system before killing Kirk's (Chris Pine) parents, Kirk himself (he got better), Captain Pike (Bruce Greenwood) (he did not), a huge portion of the population of 2259 San Francisco, and, perhaps most famously and most gratuitously, all but a tiny sliver of the entire Vulcan race. For long-time fans of the Star Trek franchise - who already had to accommodate themselves once to the death of their beloved twenty-fourth century with the end of VOY and the move to prequel series in ENT - the rebooting of the entire Trek universe into the Abramsverse felt like a death on multiple levels: not simply the now-inescapable loss of the original actors portraying those roles (most strongly tokened by the death of Leonard Nimoy early in Star Trek Beyond 's preproduction, and then echoed by the death of the actor playing the new Chekhov (Anton Yelchin) in a freak accident shortly before the film's release),1 not simply the obsolescing of the decades of characters and stories set during the original timeline, and not simply (let's just say it) by what Star Trek turning 50 says about how old some of us seem to be getting, but also the death of the ethos of optimistic, utopian futurity that had driven creative works set in the Star Trek universe since its inception in 1966.The new Star Trek universe - crafted by J.J. Abrams, who wore his lack of interest in the original Star Trek as a badge of honour during publicity for Star Trek (US 2009) - was something else entirely. Trek only in name: Roddenberry's utopia was replaced by a paranoid and militaristic Federation, scarred and traumatised by loss, seeing space as a site of horror, threat and murder rather than wonder. …

Testing students under cognitive capitalism: knowledge production of twenty-first century skills

Scholars studying the global governance of education have noted the increasingly important role corporations play in educational policy making. I contribute to this scholarship by examining the Assessment and Teaching of twenty-first century skills (ATC21S™) project, a knowledge production apparatus operating under cognitive capitalism. I analyze how ATC21S gains symbolic power and authority as it defines what counts in education through three key processes: (1) By legitimizing and disseminating new knowledge about twenty-first century skills; (2) By implementing this knowledge concretely in schools and (3) By embedding this new knowledge within a global alliance. I suggest that the knowledge produced by ATC21S in calculating and measuring twenty-first century skills contributes to the capture of living labor and its reproduction for the knowledge economy through the school system.

Compensation for a lip-tube perturbation in 4-year-olds: Articulatory, acoustic, and perceptual data analyzed in comparison with adults

The nature of the speech goal in children was investigated in a study of compensation strategies for a lip-tube perturbation. Acoustic, articulatory, and perceptual analyses of the vowels /y/ and /u/ produced by ten 4-year-old French speakers and ten adult French speakers were conducted under two conditions: normal and with a large tube inserted between the lips. Ultrasound and acoustic recordings of isolated vowels were made in the normal condition before any perturbation, for each of the trials in the perturbed condition, and in the normal condition after the perturbed trials. Data revealed that adult participants moved their tongues in the perturbed condition more than children did. The perturbation was generally at least partly compensated for during the perturbed trials in adults, but children did not show a typical learning effect. In particular, unsystematic improvements were observed during the sequence of perturbed trials, and after-effects were not clear in the articulatory domain. This suggests that children may establish associative links between multisensory phonemic representations and articulatory maneuvers, but those links may mainly rely on trial-to-trial, error-based feedback correction mechanisms rather than on the internal model of the speech production apparatus, as they are in adults.

The Role of Foreign Capital Invested in the Form of Foreign Direct Investment in the Economy of the Opolskie Voivodship in the Years 1990–2015

The article provides an assessment of the role of FDI in the regional economy based on the levels of economic efficiency: structural changes of the economy, economic stimulating activity, employment, modernization of the production apparatus and exchange with foreign countries. The following considerations seek to answer the questions to what extent has FDI become a catalyst for economic growth in the region and has it been a tool for benefiting the investors. The author drew attention to the effects generated by foreign companies in the domestic environment and their response to the global economic crisis.

Fluidized Bed Agglomeration Diagnosis Based on Wavelet Packet Entropy and Gaussian Test

Aiming at the synthesis process through the ethylene polymerization by virtue of fluidized bed reactors, this paper proposed a different approach for agglomeration monitoring and early alarming in polymerization reaction with Gaussian test of wavelet packet entropies from low-frequency audible acoustic signals. In comparison to high-frequency acoustic emission signals, audible acoustic signals can reduce the signal bandwidth, simplify the signal processing circuit, facilitate the real-time measurement, and fault detection. Compared with the approach based on regression modeling and pattern recognition, this approach can overcome the defects of false alarm and missing alarm caused by inadequate samples and weak generalization capability of diagnosis model and is easy to be implemented. Experiments in a pilot plant have verified the effectiveness of the approach, and earlier warning could be realized compared with the existing approaches on the production apparatus (material level detection and temperature measurement).

CONCEPTUAL APPROACHES TO FORMING MECHANISM OF INVESTMENT SAFETY REALIZATION

The purpose of the paper is theoretical justification of theoretical approaches while developing the mechanism of the state investment safety. The tasks of the system of the national economy investment safety are the following: developing investment potential, creating favourable investment climate, forming mechanisms of stable investment activity in the key branches of economy. At the same time, it should also be noted that the complex approach that would allow sufficiently justifying and practically solve the problems of defining indicators, factors of the investment policy and directions of its assurance in realization of the mechanism of investment policy is not sufficiently developed nowadays. This fact determines research topicality. The issue of assuring investment safety is of a special importance in Ukraine that has to assure market economy development, to overcome deformations in the economy structure, to renew products and production apparatus in the industry, to master new kinds of activities. Methodology. The survey is based on the generalization and development of views of the scientific-economic schools, uses approaches of the international agencies and recommendation and normative materials of Ukraine concerning realization of the state investment policy as a totality of interrelated levels and subsystems that allows establishing main functions of the investment safety system. Results of the survey shows that the mechanism of investment safety includes some kinds, forms and methods of organizing investment relations and investment activity, ways of their quantitative determination and establishing interdependence. The concept of investment policy is based on the complex approach and includes the blocks which are locally structured in such way that they allow forming adequate system of its indicators and conducting monitoring of their changes under the influence of the determined factors. The peculiarities and elements of realizing investment safety are determined on the basis of the suggested concept. Criteria assessment of the national economy investment safety should include assessment of: ratio of the national and foreign investments; assurance of the enlarged recreation; level of economy restructuring and re-equipping; level of accumulated resources; level of financing scientific-technical sphere. Low level of investment safety is explained by the lack of wide range of investment objects and imperfection of investment mechanisms, as well as the lack of developed investment market. Practical implications. The suggested conceptual statements concerning formation of the mechanism of realizing investment safety determine unity in the system of economic interests and participants of the investment sphere, as well as solving collisions that appear between them. The priority directions of the state policy in assuring investment safety should become the following: creating favourable macroeconomic and entrepreneurial environment, promoting development of business, protecting owners and strengthening efficiency and transparency of the use of state finances. Value/originality. The suggested conceptual principles of forming efficient mechanism of investment safety give the reason for forming an appropriate system of indicators and allow determining prospects and threads to the investment safety level in the real time.

Assessing transboundary scientific collaboration in the Great Lakes of North America

Sustainably managing the Great Lakes of North America (including ecosystem health, fisheries, tourism, and water quality) in a transboundary regulatory setting represents a significant and enduring challenge for society. Recognizing the role that scientific institutions can play in framing problems, informing responses, stimulating public debate, and monitoring the effectiveness of policy actions in diverse contexts, we assess the properties of the Great Lakes knowledge production apparatus. Using bibliometric analyses, the frequency and intensity of Great Lakes-related scientific knowledge collaboration are analyzed over the 15-year period from 2000 to 2014, focusing on organizational, institutional, and geographic characteristics. The results reveal generally robust scientific collaboration between government and academic institutions but also a remarkable USA–Canada cross-border disjuncture, the latter being a surprising trend given the transboundary nature of the social–ecological issues being faced. Our findings inform ongoing efforts to enhance transboundary governance capacity in the Great Lakes region.

히트파이프를 이용한 폴리실리콘 제조용 다중권선 변압기 설계에 관한 연구

This paper reflected the Temperature test value and compare the Computational Fluid Dynamic analysis value on particular characteristics of the multi-winding transformer's cooling apparatus equipped by heat pipe with excellent heat transfer ability on design Particularly if you look at multi-winding transformers that supply high-quality Direct current power to silicon production apparatus, heat generation due to high current supply is excessive thus, an innovative cooling apparatus is required in particular for reduced size transformer.

Futuristic Three-Dimensional Printing and Personalized Neurosurgery

Figure 1. Continuous liquid interface production apparatus. From Tumbleston JR, Shirvanyants D, Ermoshkin N, Janusziewicz R, Johnson AR, Kelly D, Chen K, Pinschmidt R, Rolland JP, Ermoshkin A, Samulski ET, DeSimone JM: Additive manufacturing. Continuous liquid interface production of 3D objects. Science 347:1349-1352, 2015. Reprinted with permission from AAAS. Disruptive technologies are rare phenomena. However, when they do come about, they have the potential to change the course of entire industries. Such is the case with the new three-dimensional (3D) printing technology from Carbon3D Inc. (Redwood City, California, USA), dubbed Continuous Liquid Interface Production (CLIP). With its innovative approach to additive manufacturing, CLIP has the potential to usurp and revolutionize 3D printing, with reverberations into several fields, including neurologic surgery. Conventional additive manufacturing, like Polyjet, Fused Deposition Modeling (FDM), Stereolithography (SLA) and Laser Sintering technology (SLS), function by adding materials layer by layer. For these techniques, two-dimensional printing is repeated over and over again until a 3D physical rendering is produced. Consequently, such a process takes several hours and in most cases results in an unfinished and “pixelated-like” end product. A post-processing interval adds further time to the process. CLIP technology, as described by Tumbleston et al., prints 3D physical models in a continuous fashion as opposed to layer by layer in conventional machines. This approach capitalizes on 2 opposing forces: ultraviolet (UV) light that promotes polymerization of resin, in contrast to oxygen (O2), which inhibits the polymerization of resin. The apparatus itself consists of a bath filled with resin, an O2-permeable and UVpermeable membrane, a build support plate, and a UV imaging unit (Figure 1). Polymerization of the intended part begins when a continuous sequence of UV images is projected through the O2permeable, UV-transparent window below the resin bath; this creates a layering, whereby directly above the window a liquid dead zone rich in O2 exists, where no polymerization occurs. Directly above the dead zone, O2 concentration decreases, and polymerization of the resin and construction of the 3D model occur, guided by the projected UV images. Simultaneously, the 3D part is elevated out of the resin bath by a continuously elevating build support plate (Video I). This process can speed up 3D printing up to 100-fold, producing a high-resolution finished or near-finished product without the layerings of 3D printing. A job that used to take hours now takes only minutes to complete. Moreover, the spectrum of

Mobile Production: Spatialized Labor, Location Professionals, and the Expanding Geography of Television Production

This article addresses the spatial challenges facing television laborers amid an increasingly expansive and conngent environment of local production incentives. Pushing away from the term runaway production and its limited engagement with local, spatialized dynamics of labor, I argue for a consideration of “mobile production,” wherein television series are capable of being executed in an increasingly wide range of locations—not necessarily Los Angeles—and capable of being moved should changes in an incentive system create the need to do so. Through personal interviews and analysis of industry discourse, this case study of location professionals considers how the mobility of production affects below-the-line local laborers. Mobile production relies on location workers more than any other job category, but the capacities of these workers are geographically specific: while they make the globalized mobile production apparatus viable, they are also the most likely to be left behind if incentive structures shift and Hollywood producers “go mobile” and move on.

Designing an optimum pulsed magnetic field by a resistance/self-inductance/capacitance discharge system and alignment of carbon nanotubes embedded in polypyrrole matrix.

In this work, an optimized pulsed magnetic field production apparatus is designed based on a RLC (Resistance/Self-inductance/Capacitance) discharge circuit. An algorithm for designing an optimum magnetic coil is presented. The coil is designed to work at room temperature. With a minor physical reinforcement, the magnetic flux density can be set up to 12 Tesla with 2 ms duration time. In our design process, the magnitude and the length of the magnetic pulse are the desired parameters. The magnetic field magnitude in the RLC circuit is maximized on the basis of the optimal design of the coil. The variables which are used in the optimization process are wire diameter and the number of coil layers. The coil design ensures the critically damped response of the RLC circuit. The electrical, mechanical, and thermal constraints are applied to the design process. A locus of probable magnetic flux density values versus wire diameter and coil layer is provided to locate the optimum coil parameters. Another locus of magnetic flux density values versus capacitance and initial voltage of the RLC circuit is extracted to locate the optimum circuit parameters. Finally, the application of high magnetic fields on carbon nanotube-PolyPyrrole (CNT-PPy) nano-composite is presented. Scanning probe microscopy technique is used to observe the orientation of CNTs after exposure to a magnetic field. The result shows alignment of CNTs in a 10.3 Tesla, 1.5 ms magnetic pulse.

Sound production in Onuxodon fowleri (Carapidae) and its amplification by the host shell.

Onuxodon species are well known for living inside pearl oysters. As in other carapids, their anatomy highlights their ability to make sounds but sound production has never been documented in Onuxodon. This paper describes sound production in Onuxodon fowleri as well as the anatomy of the sound production apparatus. Single-pulsed sounds and multiple-pulsed sounds that sometimes last more than 3 s were recorded in the field and in captivity (Makemo Island, French Polynesia). These pulses are characterized by a broadband frequency spectrum from 100 to 1000 Hz. Onuxodon fowleri is mainly characterized by its ability to modulate the pulse period, meaning that this species can produce pulsed sounds and tonal-like sounds using the same mechanism. In addition, the sound can be remarkably amplified by the shell cavity (peak gain can exceed 10 dB for some frequencies). The sonic apparatus of O. fowleri is characterized by a rocker bone in front of the swimbladder, modified vertebrae and epineurals, and two pairs of sonic muscles, one of which (primary sonic muscle) inserts on the rocker bone. The latter structure, which is absent in other carapid genera, appears to be sexually dimorphic suggesting differences in sound production in males and females. Sound production in O. fowleri could be an example of adaptation where an animal exploits features of its environment to enhance communication.

Electric field-oriented growth of carbon nanotubes and Y-branches in a needle-pulsed arc discharge unit: mechanism of the production

Carbon nano-onions, multiwall carbon nanotubes and Y-branched nanotubes are synthesised in a simple production apparatus. A pulsed plasma is generated by discharging a high voltage needle pulse between two graphite electrodes. A strong electric field is presented along anode and cathode electrodes. The pulse width is 0.3 μs. Acetone vapour, as a precursor, is introduced to the plasma through a graphite nozzle in the cathode assembly. A magnetic field, perpendicular to the plasma path, is provided. The possibility of carbon nanotube production through a short-pulsed arc discharge technique is investigated in this article. The results show that adding an electric field between electrodes prevents carbon ions’ dispersion, facilitates charge transferring between ions and electrodes, orients the growth of carbon nanotubes along the applied electric field and finally makes it possible to produce functionalised carbon nanoparticles such as Y-branch nanotubes and nanoknees. In this work, the growth mechanism of carbon nanotubes in a needle-pulsed arc-discharge reactor is discussed. And a possible explanation is provided for the synthesis of Y-branch carbon nanotubes. The products are examined by using scanning probe microscopy technique.

Synthesis of Carbon Nanotubes and Nano-onions Using Electric Field Induced Needle-Pulsed Arc Discharge Plasma

Carbon nano-onions and multi-walled carbon nanotubes (MWCNTs) are synthesized by needle-pulsed arc discharge plasma. In a simple production apparatus, a needle pulsed plasma is applied between two graphite electrodes in the presence of an electric field between anode and cathode. The possibility of carbon nanotube production by short pulsed arc discharge technique is investigated in this article. The pulse width is 0.3 μsec. Acetone vapor as carbon source is introduced to plasma. A magnetic field, perpendicular to the plasma path, is provided. The advantages of using short pulsed plasma are studied in this work. The results show that applying a DC electric field between electrodes, increases plasma tendency toward cathode, enhances the chance of plasma-hydrocarbon interaction, prevents carbon ions from dispersion and finally makes it possible to produce CNTs by low-power short pulses in an arc-discharge plasma reactor. The products are examined using SPM techniques. In this work, adding an electric field to the pulsed plasma techniques, suggests a new method to produce carbon nano particles (CNPs) by short current pulses with lifetime of below one microsecond.

Modifications in call characteristics and sonic apparatus morphology during puberty in Ophidion rochei (actinopterygii: Ophidiidae)

Juveniles, females, and males of Ophidion rochei share similar external morphology, probably because they are mainly active in the dark, which reduces the role of visual cues. Their internal sonic apparatuses, however, are complex: three pairs of sonic muscles, and highly modified vertebrae and ribs are involved in sound production. The sonic apparatus of males differs from juveniles and females in having larger swimbladder plates (modified ribs associate with the swimbladder wall) and sonic muscles, a modified swimbladder shape and a mineralized structure called the "rocker bone" in front of the swimbladder. All of these male traits appear at the onset of sexual maturation. This article investigates the relationship between morphology and sounds in male O. rochei of different sizes. Despite their small size range total length (133-170 mm TL), the five specimens showed pronounced differences in sound-production apparatus morphology, especially in terms of swimbladder shape and rocker bone development. This observation was reinforced by the positive allometry measured for the rocker bone and the internal tube of the swimbladder. The differences in morphology were related to marked differences in sound characteristics (especially frequency and pulse duration). These results suggest that male calls carry information about the degree of maturity. Deprived of most visual cues, ophidiids probably have invested in other mechanisms to recognize and distinguish among individual conspecifics and between ophidiid species. As a result, their phenotypes are externally similar but internally very different. In these taxa, the great variability of the sound production apparatus means this complex system is a main target of environmental constraints.

Les dangers de la bulle immobilière chinoise

Depuis le milieu de la decennie 2000, le secteur de l’immobilier chinois connait une vive expansion, mais la bulle ainsi formee n’est que la partie emergee de difficultes beaucoup plus profondes. Le controle de la speculation immobiliere apparait ainsi d’autant plus risque pour l’economie chinoise que cette derniere reflete aussi bien les difficultes financieres des autorites locales que des problemes de rentabilite beaucoup plus serieux rencontres par l’appareil productif.

The Mineral Character and Geomechanical Properties of the Transitional Rocks from the Mesozoic-Neogene Contact Zone in the Bełchatów Lignite Deposit

Beginning more than 30 years ago, opencast lignite mining in the "Bełchatów" area is an important source of accompanying minerals. Lignite mining in the "Bełchatów" mine yields, on average, more than 35 million tonnes per annum and requires removing more than 110 million cubic meters of overburden. Therefore the mine outside of the main mineral exploitation of lignite, leads to a large-scale economy of accompanying minerals. Part of the minerals are present in the overburden and are exposed on the slopes of the opencast mine; these minerals are selectively exploited in the event of the absence of recipients stored on anthropogenic deposits. The object of this mineralogical-geochemical study is a group of transitional rocks such as opoka-rocks, gaize and marls exposed when contact occurs between Neogene sediments and Mesozoic basement rocks in the "Bełchatów" lignite deposit. In the case of these rocks, during preliminary geological research carried out on the mine, doubt often appear as to their explicit petrographic character and hence their practical use. Advanced mineralogical methods allow mistakes in their identification to be avoided and a geomechanical study indicates possible direction of their practical use. The heterogeneous petrographic character of the examined rocks required the use of a broad research spectrum. The following microscopes were used in the framework of the mineralogical research: Polarizing Olimpus BX51 and electron (SEM) FEI Quanta 200FEG equipped with an X-ray spectrometer (EDX Genesis) and backscattered electron detector (BSE). In addition, observations were carried out using a cathodoluminescence apparatus, the Cambridge Image Technolgy Ltd CCL 8200 mk3 model, and a polarizing microscope, type Nikon Optiphot 2. Determination of the phase composition (qualitative and quantitative) was made using X-ray diffraction and utilizing the powder method of Debye-Sherrer. An X-ray diffractometer, a Philips PW 3020 X'PERT, was also used in the study. Analyses by Fourier transmission infrared spectroscopy were performed using the production apparatus BIO-RAD, model FTS 165, equipped with a package of programs for the digital processing of results. The chemical composition was determined by atomic absorption spectroscopy (AAS) using a spectrophotometer Philips PU 9100Xi Camera SX-100 and atomic emission spectroscopy with inductively coupled plasma (ICP AES) using spectrometer 40 PLASMA. The geomechanical properties were determined in accordance with the following standards: open and total porosity (PN-EN 1936:2001) compressive strength in air – dried state (PN-EN 1926:2001), bulk density and density (PN-EN 1936:2001), relative humidity (PN-EN 1925:2001); absorbability of stone material (PN-EN 13755:2002) and abrasion on the face of Boehme (PN-84/B-04111). Mineralogical-petrographic studies of the transitional rocks showed that the dominant component was SiO 2 which was presented in the form of opal type A and CT, chalcedony, quartz and microquartz. In addition, it was found that the rocks studied had been covered by secondary mineralization processes. The observations carried out showed that these rocks underwent primary silicification and decalcination processes, which contributed to the diverse petrographic nature of the rocks studied and secondarily experienced a change in their physico-mechanical properties. The silification process was the result of diagenetic processes taking place within the Neogene argillaceous rocks occurring when a sub-coal series is situated in the immediate vicinity of the bedrock. There was a release of extruded silica-rich water from the clays during the mechanical compaction process. Some amounts of silica may also be derived from plagioclase dissolution and the transformation of terrigenous material, mainly grains of potassium feldspar. The precipitation of silica from porous solutions occurred most when coinciding with the presence of carbonic acid formed by the decomposition of organic substances of vegetable origin. The studies carried out have a significant practical implication, as the transitional sediments from the "Bełchatów" lignite deposit can be used in the production of building materials. Against the background of a number of published papers on the rocks accompanying lignite seams there is a lack of the "Bełchatów" mineralogical-petrographic studies of the transitional sediments in the Mesozoic-Neogene contact zone in the "Bełchatów" lignite deposit taking into account the aspect of raw materials. This paper has been produced to fill the void in this area.

Políticas públicas y migración interna en la República Bolivariana de Venezuela contemporánea

Transformations in the production apparatus, changes in the global economy and certain political and social factors have given rise to various patterns of territorial mobility. This paper analyses trends in internal migration in the Bolivarian Republic of Venezuela from 1971 to 2001. On the basis of information from national population and housing censuses, multiregional origin-destination matrices were established identifying the direction of migration flows and traditional and emerging push and pull factors of migration. Using the human development index, migratory flows between regions of high, medium and low levels of human development were determined, therefore demonstrating the uneven distribution of production activities in the country. Lastly, the results were analysed in the context of historical and structural processes, showing the link between policy decisions, each region’s economic emergence and the dynamics of internal migration.

Chemical composition and in vitro total gas and methane production of forage species from the Mid Rift Valley grasslands of Ethiopia

AbstractThere is increasing interest in sustainable land use in the tropics to optimize animal production while also reducing methane (CH4) emissions, but information on nutritive value and CH4‐emission potential of tropical forage species is limited. Samples of 24 grasses and five other forages were collected during the main rainy season on randomly positioned quadrats in semi‐arid grassland in the Mid Rift Valley of Ethiopia. Samples were pooled by species, analysed for chemical composition and incubated with rumen fluid to determine total gas and CH4‐emission potentials using a fully automated in vitro gas production apparatus. Organic matter digestibility (OMD) and metabolizable energy (ME) contents were calculated from chemical composition and gas production data. Large variability was observed among forages for all nutritional variables considered. The grasses Eleusine multiflora, Pennisetum stramineum, Dactyloctenium aegyptium, Eragrostis aspera, Cenchrus ciliaris and Eragrostis cilianensis showed relatively high OMD (68–72%) and ME values (9·1–10·2 MJ kg−1 dry matter). Melinis repens, E. multiflora and the non‐legume forb Zaleya pentandra showed relatively low CH4 to total gas ratios; these species may have potential for use in low CH4‐emission forage diets. Acacia tortilis fruits had high content of crude protein and moderate ME values, and may be an ideal feed supplement for the grazing ruminant. Sodium content was below the recommended level for ruminants in all the forage species. Overall, the pasture stand during the main growing season was evaluated as having moderate nutritional quality.

Interspeaker variability in relative tongue size and vowel production

The tongue varies across speakers in terms of the proportion of the overall speech production apparatus that it occupies. Differences in tongue size have the potential to result in speaker-specific articulatory strategies for shaping the vocal tract area function and, in turn, individual patterns of vowel acoustics. The present study examines the interplay between relative tongue size and vowel production using real-time magnetic resonance imaging with synchronous audio. Two populations of native American English subjects are considered, one containing healthy adult speakers with no relevant pathologies, and another containing speakers who had undergone glossectomy as treatment for tongue cancer. All subjects were imaged in the midsagittal plane while reading phonetically balanced English sentences. The size of the tongue and the speech production apparatus were quantified from an overall average posture, and their ratio was correlated with the shape of the vowel space in terms of acoustics (e.g., formant frequencies), constrictions (i.e., location and degree of minimum constriction), and parameterized vocal tract cross-distance functions. Results indicate that relative tongue size can be used to explain and predict observable interspeaker differences in vowel production.