13,930 research outputs found
Collaboration within the UK Farm Industry
This paper addresses the effectiveness of the traditional models of cooperation, and analyses best practices in other commercial sectors in order to identify transferable elements. The Report of the Policy Commission on the Future of Farming and Food (2002) identified a need for farmers to cooperate and collaborate more effectively in their business activities in order to be more competitive. The Plunkett Foundation (1992) suggests that in order to play an important role in the maintenance of the rural economy the Farmer Controlled Business should adopt more imaginative approaches. Using an inductive grounded theory approach and guided interview techniques, experts in the field of business collaboration were selected using a purposive sample approach and interviewed using an iterative Delphi model. Interviewees were leading academics, government officials and managers of the most profitable and/or innovative EU based cooperatives. Having been asked to identify and evaluate the operational characteristics of traditional models of cooperation, respondents were encouraged to identify the ideal characteristics of any replacement business frameworks. A culture of "arm focus"and a lack of "global" understanding were identified as very important factors affecting cooperation. In addition to this, the intrinsic limitations of the traditional model of cooperation were recognized as an important limitation, as well as the personal characteristics and skills of the members were identified as relevant barriers. The paper concludes that addressing the problems of culture and attitude is a long-term process. Therefore the solution could come from models, where the members do not necessarily have the required vision or culture, but they are part of a bigger organization that has the needed consumer and food chain focus. The key factor is to gain recognition of the need to fundamentally address organizational structure.cooperatives, collaboration, supply food chain, organizational structure, farming, Agribusiness, Industrial Organization,
Chemical Compositions of Four Metal-poor Giants
We present the chemical compositions of four K giants CS 22877-1, CS
22166-16, CS22169-35 and BS 16085 - 0050 that have [Fe/H] in the range -2.4 to
-3.1. Metal-poor stars with [Fe/H] < -2.5 are known to exhibit considerable
star - to - star variations of many elements. This quartet confirms this
conclusion. CS 22877-1 and CS 22166-16 are carbon-rich. There is significant
spread for [/Fe] within our sample where [/Fe] is computed from
the mean of the [Mg/Fe], and [Ca/Fe] ratios. BS 16085 - 0050 is remarkably
enriched with a mean [/Fe] of 0.7 but CS 22169-35 is
-poor. The aluminium abundance also shows a significant variation over
the sample. A parallel and unsuccessful search among high-velocity late-type
stars for metal-poor stars is described.Comment: 14 pages (text), 4 tables, 3 figures, Accepted for publication in
PAS
Direct constraints on the dark matter self-interaction cross-section from the merging galaxy cluster 1E0657-56
We compare new maps of the hot gas, dark matter, and galaxies for 1E0657-56,
a cluster with a rare, high-velocity merger occurring nearly in the plane of
the sky. The X-ray observations reveal a bullet-like gas subcluster just
exiting the collision site. A prominent bow shock gives an estimate of the
subcluster velocity, 4500 km/s, which lies mostly in the plane of the sky. The
optical image shows that the gas lags behind the subcluster galaxies. The
weak-lensing mass map reveals a dark matter clump lying ahead of the
collisional gas bullet, but coincident with the effectively collisionless
galaxies. From these observations, one can directly estimate the cross-section
of the dark matter self-interaction. That the dark matter is not fluid-like is
seen directly in the X-ray -- lensing mass overlay; more quantitative limits
can be derived from three simple independent arguments. The most sensitive
constraint, sigma/m<1 cm^2/g, comes from the consistency of the subcluster
mass-to-light ratio with the main cluster (and universal) value, which rules
out a significant mass loss due to dark matter particle collisions. This limit
excludes most of the 0.5-5 cm^2/g interval proposed to explain the flat mass
profiles in galaxies. Our result is only an order-of-magnitude estimate which
involves a number of simplifying, but always conservative, assumptions;
stronger constraints may be derived using hydrodynamic simulations of this
cluster.Comment: Text clarified; some numbers changed slightly for consistency with
final version of the accompanying lensing paper. 6 pages, uses emulateapj.
ApJ in pres
Water vapor emission from IRC+10216 and other carbon-rich stars: model predictions and prospects for multitransition observations
We have modeled the emission of H2O rotational lines from the extreme C-rich
star IRC+10216. Our treatment of the excitation of H2O emissions takes into
account the excitation of H2O both through collisions, and through the pumping
of the nu2 and nu3 vibrational states by dust emission and subsequent decay to
the ground state. Regardless of the spatial distribution of the water
molecules, the H2O 1_{10}-1_{01} line at 557 GHz observed by the Submillimeter
Wave Astronomy Satellite (SWAS) is found to be pumped primarily through the
absorption of dust-emitted photons at 6 m in the nu2 band. As noted by
previous authors, the inclusion of radiative pumping lowers the ortho-H2O
abundance required to account for the 557 GHz emission, which is found to be
(0.5-1)x10^{-7} if the presence of H2O is a consequence of vaporization of
orbiting comets or Fischer-Tropsch catalysis. Predictions for other
submillimeter H2O lines that can be observed by the Herschel Space Observatory
(HSO) are reported. Multitransition HSO observations promise to reveal the
spatial distribution of the circumstellar water vapor, discriminating among the
several hypotheses that have been proposed for the origin of the H2O vapor in
the envelope of IRC+10216. We also show that, for observations with HSO, the
H2O 1_{10}-1_{01} 557 GHz line affords the greatest sensitivity in searching
for H2O in other C-rich AGB stars.Comment: 35 pages, 12 figures, to be published in The Astrophysical Journa
Exploring Beginning Latino Farmers and Ranchers' Willingness to Become Involved in Community Activities in Rural Missouri
Presentation made at Latinos in the Heartland (13th : 2015 : Columbia, Mo.) and published in the annual conference proceedings.In 2013, we conducted two workshop series, each consisting of 10 sessions, focused on how to improve financial capacity of agribusiness and to gain access to community resources. As part of the workshops, eighteen Latino farmers and ranchers in Southwest Missouri completed a survey that analyzed their disposition towards becoming involved in community activities over the upcoming six months. The willingness of the Latino farmers and ranchers to become involved in community activities was explored across five indicators: 1. to be more engaged in community leadership roles, 2. to form new connections in the community, 3. to display more tolerance when working with others, 4. to develop a community action plan, and 5. to implement a community project. A total of 140 answers to each indicator were collected from participants and were analyzed using symmetric responses, where 1 was coded as "not willing," 2 was coded as "reluctant," 3 as "neutral," 4 as "moderate willing," and 5 as "very willing." Participants' responses to each of those five indicators showed that many (46%, 43%, 51%, 53% and 48%) beginning farmers and ranchers were "very willing" to involve themselves with community projects and activities during the upcoming six months. The willingness of participants to become involved in community activities helped us to know their predisposition to integrate and assimilate into the communities where they lived. It is argued that Latino immigrants have trouble assimilating into mainstream US culture (Huntington, 2004), and those who do assimilate, belong to a cluster with the following characteristics: spatial concentration, high incomes, intermarriage, English fluency and high levels of embeddedness in Anglo-social contexts (South et al. 2005, Waters & Jimenez, 2005). The predisposition to participate in community activities is positively related with Waters and Jimenez's perception (2005) that US communities have evolved in absorbing new immigrants and continual immigrant replenishment makes assimilation less visible. Other factors influencing positive integration and assimilation may be attributed to the population size of that immigrant group in the community and the population size of the rural community where they immigrated. A multistate conference about integration of immigrants Proceedings of the 13th Annual Conference Latinos in the Heartland: Growing Together in New Destination Areas www.cambio.missouri.edu/Library/ Key words: beginning Latino farmers and ranchers, immigrant integration, rural communities
Electric-field tuning of the valley splitting in silicon corner dots
We perform an excited state spectroscopy analysis of a silicon corner dot in
a nanowire field-effect transistor to assess the electric field tunability of
the valley splitting. First, we demonstrate a back-gate-controlled transition
between a single quantum dot and a double quantum dot in parallel that allows
tuning the device in to corner dot formation. We find a linear dependence of
the valley splitting on back-gate voltage, from to with a slope of (or equivalently a slope
of with respect to the effective field). The
experimental results are backed up by tight-binding simulations that include
the effect of surface roughness, remote charges in the gate stack and discrete
dopants in the channel. Our results demonstrate a way to electrically tune the
valley splitting in silicon-on-insulator-based quantum dots, a requirement to
achieve all-electrical manipulation of silicon spin qubits.Comment: 5 pages, 3 figures. In this version: Discussion of model expanded;
Fig. 3 updated; Refs. added (15, 22, 32, 34, 35, 36, 37
Population distribution models: species distributions are better modeled using biologically relevant data partitions
<p>Abstract</p> <p>Background</p> <p>Predicting the geographic distribution of widespread species through modeling is problematic for several reasons including high rates of omission errors. One potential source of error for modeling widespread species is that subspecies and/or races of species are frequently pooled for analyses, which may mask biologically relevant spatial variation within the distribution of a single widespread species. We contrast a presence-only maximum entropy model for the widely distributed oldfield mouse (<it>Peromyscus polionotus</it>) that includes all available presence locations for this species, with two composite maximum entropy models. The composite models either subdivided the total species distribution into four geographic quadrants or by fifteen subspecies to capture spatially relevant variation in <it>P. polionotus </it>distributions.</p> <p>Results</p> <p>Despite high Area Under the ROC Curve (AUC) values for all models, the composite species distribution model of <it>P. polionotus </it>generated from individual subspecies models represented the known distribution of the species much better than did the models produced by partitioning data into geographic quadrants or modeling the whole species as a single unit.</p> <p>Conclusions</p> <p>Because the AUC values failed to describe the differences in the predictability of the three modeling strategies, we suggest using omission curves in addition to AUC values to assess model performance. Dividing the data of a widespread species into biologically relevant partitions greatly increased the performance of our distribution model; therefore, this approach may prove to be quite practical and informative for a wide range of modeling applications.</p
The 1995-1996 Decline of R Coronae Borealis - High Resolution Optical Spectroscopy
A set of high-resolution optical spectra of RCrB acquired before, during, and
after its 1995-1996 decline is discussed. All of the components reported from
earlier declines are seen. This novel dataset provides new information on these
components including several aspects not previously seen in declines of RCrB
and other RCBs. In the latter category is the discovery that the decline's
onset is marked by distortions of absorption lines of high-excitation lines,
and quickly followed by emission in these and in low excitation lines. This
'photospheric trigger' implies that dust causing the decline is formed close to
the star. These emission lines fade quickly. After 1995 November 2, low
excitation narrow (FWHM ~12 km s-1) emission lines remain. These appear to be a
permanent feature, slightly blue-shifted from the systemic velocity, and
unaffected by the decline except for a late and slight decrease of flux at
minimum light. The location of the warm, dense gas providing these lines is
uncertain. Absorption lines unaffected by overlying sharp emission are greatly
broadened, weakened, and red-shifted at the faintest magnitudes when scattered
light from the star is a greater contributor than direct light transmitted
through the fresh soot cloud. A few broad lines are seen at and near minimum
light with approxiamately constant flux: prominent among these are the He I
triplet series, Na I D, and [N II] lines. These lines are blue-shifted by about
30 km s(-1) relative to the systemic velocity with no change in velocity over
the several months for whicht he lines were seen. It is suggested that these
lines, especially the He I lines, arise from an accretion disk around an unseen
compact companion, which may be a low-mass white dwarf. If so, R CrB is similar
to the unusual post-AGB star 89 Her.Comment: 31 pages, 26 figure
Electrochemically site-selective alkoxylation of twisted 2-arylbenzoic acids via spirolactonization
The Electrochemical Cross-Dehydrogenative Coupling (ECDC) of twisted biphenyl-2-carboxylic acids with aliphatic alcohols provides 4′-alkoxyspirolactones which isomerize, under mild basic conditions, to give 4′-alkoxy-2-phenylbenzoic acids. This site-selective alkoxylation was readily adapted to 1 mmol scale and is environmentally friendly, as no terminal oxidants are needed and H2 is the only residue. The suitability of diphenic acid derivatives in this two-step protocol is noteworthy, especially for axially chiral substrates that can be functionalized with retention of the configuration and of the enantiomeric purity. We have proposed a plausible mechanism based on experimental pieces of evidence that support the single-electron oxidation of the carboxylate, formed by deprotonation of the biphenyl-2-carboxylic acids with 2,6-lutidine, and DFT calculations that suggest a very fast spirocyclization of the intermediate σ-aroyloxyl radical. Competing pathways to benzocoumarins were also examined by computational studies.This work was generously supported by the Spanish Ministerio de Ciencia, Innovación y Universidades (MICIU; grant no. CTQ2017-88171-P) and the University of Alicante (grant no. VIGROB-285/19). I. B. acknowledges the Spanish MICIU for a Juan de la Cierva-incorporación grant (no. IJCI-2017-33706)
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