An Economic Risk Analysis of No-till Management for the Rice-Soybean Rotation System used in Arkansas

Arkansas is the top domestic rice producer, representing nearly half of total U.S. rice production. Sediment is one of the major pollutants in rice producing areas of Arkansas. In order to mitigate this problem no-tillage management is often recommended. No-tillage is not well understood by farmers who believe that no-till is less profitable due to lower yields offsetting cost savings. This study evaluates the profitability and variability of no-till in the typical rice-soybean rotation used in Arkansas rice production. Crop yields, prices and prices for key production inputs (fuel and fertilizer) are simulated for the rotation, and net return distributions for rice, soybean and the two-year rotation are evaluated for no-till and conventional till using stochastic efficiency with respect to a function (SERF) analysis. The results indicate that both risk neutral and risk-averse rice producers would prefer no-till over conventional till management in the two year rice-soybean rotation, and that no-till soybeans contribute greatly to the overall profitability of the rotation.simulation, rice-soybean, no tillage-profitability, risk analysis, Environmental Economics and Policy, Farm Management, Resource /Energy Economics and Policy,

Measuring the Stochastic Monetary Benefits of Multiple Inlet Irrigation in Arkansas Rice Production

Irrigation fuel costs represent a significant portion of rice production expenses. Multiple inlet (MI) irrigation represents a water saving alternative to conventional flood irrigation. This study uses simulation to calculate the range of monetary benefits to MI in rice production. Water savings from MI relative to conventional flood irrigation along with rice yields, rice prices, and prices for key production inputs (diesel and fertilizer) are simulated, and stochastic rice net returns above variable and fixed expenses are calculated for different pump lifts with and without MI. Monetary benefits to MI are measured as the difference in net returns with and without MI. The results indicate MI monetary benefits depend greatly on pump lift and the presence or absence of a yield increase. Monetary benefits to MI increase as pump lifts become larger, and relatively small increases in yield resulting from MI irrigation can greatly enhance its payoff.cost, cumulative distribution functions, multiple inlet irrigation, net return, rice, stochastic, Farm Management,

Island Hopping as a Mode of Acculturation: The Experience of German Sojourners in the American Southwest

This study explores how members of a particular group of German sojourners—military and quasi-military personnel and their families—whose acculturative experience occurs largely within the closely-bounded confines of a military base, adjust to life in the American Southwest. I use a mixed-methods approach, including grounded theory, to interpret data produced by short questionnaires, in-depth interviews with eleven German participants, and my personal experience as a German sojourner

Phase coherence of an atomic Mott insulator

We investigate the phase coherence properties of ultracold Bose gases in optical lattices, with special emphasis on the Mott insulating phase. We show that phase coherence on short length scales persists even deep in the insulating phase, preserving a finite visibility of the interference pattern observed after free expansion. This behavior can be attributed to a coherent admixture of particle/hole pairs to the perfect Mott state for small but finite tunneling. In addition, small but reproducible ``kinks'' are seen in the visibility, in a broad range of atom numbers. We interpret them as signatures for density redistribution in the shell structure of the trapped Mott insulator

Bunches of misfit dislocations on the onset of relaxation of Si0.4_{0.4}Ge0.6_{0.6}/Si(001) epitaxial films revealed by high-resolution x-ray diffraction

The experimental x-ray diffraction patterns of a Si$_{0.4}$Ge$_{0.6}$/Si(001) epitaxial film with a low density of misfit dislocations are modeled by the Monte Carlo method. It is shown that an inhomogeneous distribution of 60$^\circ$ dislocations with dislocations arranged in bunches is needed to explain the experiment correctly. As a result of the dislocation bunching, the positions of the x-ray diffraction peaks do not correspond to the average dislocation density but reveal less than a half of the actual relaxation

Evaluation of competences at the community pharmacy settings

The General Level Framework (GLF) document provides a model to be used in evaluating and upgrading of pharmacists’ competences currently used in many countries. This study has several Objectives: To show the adaptation process of the GLF document to the Serbian pharmaceutical work practices and regulations; to illustrate the implementation of the GLF document; to evaluate and monitor the development of pharmacists’ competencies. Materials and Methods: The adaptation, analysis, validation and adjustment of the GLF document were conducted using the expert panel method. The implementation was conducted on a sample of pharmacists employed in Subotica Pharmacy chain. Later, the evaluation of the pharmacists’ competencies was performed at two observation points (at the beginning of the study and after 6 months) by the team of seven GLF members. Results and Discussion: The GLF document was reviewed by 14 members of the expert panel. During the content validation performed at the expert panel meeting, all competencies stated in the GLF document were rated according to their importance with an average grade of between 8.26 and 9.80 and thus reached a consensus regarding all 26 competencies. During the evaluation of the pharmacists’ competences, the greatest improvement after the second observation was noted in the “Patient consent” competency, followed by the “Drug history”, “The prescription is legal“, “Health needs”, “Provision of written information” and “Assessing outcomes of contributions” competencies. All the competencies in the GLF document were accepted for the implementation in the Subotica Pharmacy chain. Six of the competencies there was a significant improvement observed

A model of integrated practice in initial education of pre-school teachers

Već se duži niz godina govori o važnosti i značaju prakse studenata u osposobljavanju za poslove i zadatke koji se od njih očekuju. Uloga prakse (praktikuma) unutar institucijskog konteksta središnje je područje u kome se ostvaruje pripremanje studenata za budući profesionalni život. Međutim, iako se stalno ukazuje na neophodnost efikasnijeg i kvalitetnijeg pripremanja, dakle, obrazovanja i osposobljavanja studenata budućih vaspitača kao refleksivnih praktičara, do značajnih pomaka još uvek nije došlo. I dalje je prisutno izvesno nerazumevanje i nepoverenje u metodičke koncepcije iskustvene, problemske, grupne i saradničke nastave koje integrativni i refleksivni pristup učenju uzimaju kao načela delovanja. Predmet istraživanja koje će biti predstavljeno je razvijanje i provera novog nastavnog predmeta Integrativna praksa i utvrđivanje njegovog doprinosa u profesionalizaciji budućih vaspitača. Reč je o nastavnom predmetu organizovanom u trajanju od jednog semestra (VI semestar), koji u najkraćem možemo opisati kao pokušaj realizacije integrativnog procesa u nastavi kroz praktičnu obuku studenata. Istraživanje čini deo napora da se, s jedne strane, razviju savremeni strateški pristupi nastavi koji se odnose na integrativno učenje i obrazovanje studenata kao kreatora integrativnog pristupa u radu sa decom predškolskog uzrasta, kao istraživača realnih procesa učenja i stvaranja znanja kroz projekatski pristup u radu sa decom, i da se, sa druge strane, otkriju i istraže odlike obrazovanja budućih vaspitača za refleksivnu praksu i doprinese njihovom razvijanju kao budućih refleksivnih praktičara. Posebno nas je zanimalo da, na uzorku od 60 studenata, polaznika nastavnog predmeta Integrativna praksa, ispitamo koliko sadržaj ovog nastavnog predmeta i način organizovanja nastave doprinose razvoju studenata, budućih vaspitača kao refleksivnih praktičara. Rezultati istraživanja upućuju na nekoliko opštih zaključaka vezanih za implicitne teorije studenata - shvatanje deteta, vaspitača, nastavnika, učenja i podučavanja: Prvi - postoje dva različita viđenja (ispitivanih problema), dve različite slike – eksplicitna i implicitna, i njihovo „mešanje“, nadjačavanje u zavisnosti od korišćene tehnike. Naime, odgovori u upitniku govore o uverenjima koja su bliža savremenim naučnim saznanjima (usmerenost prema detetu i učenju, viđenje vaspitača/nastavnika kao partnera i saradnika, učenja kao razmene), dok su odgovori dati putem crteža bliži tradicionalnom pristupu (dete je najveća vrednost, objekat ljubavi, ali bespomoćno i zavisno od odraslih; vaspitač je uzor, prenosilac znanja, neko ko brine o deci, drugi roditelj; nastavnik je model, autoritet). Odgovori o učenju i podučavanju u visokom procentu imaju konstruktivističku orijenataciju i transakcijski model podučavanja. Analiza uverenja o učenju i podučavanju pokazala je da studenti visoko procenjuju važnost usmerenosti prema detetu i učenju, što ukazuje na odmak od njihovih uverenja o ulozi vaspitača, nastavnika, deteta identifikovanih u analizi crteža...The importance and relevance of students´ practice the purpose of which is to enable them to perform the activities and tasks expected of them has been a topic for discussion for many years. The role of practice (a practicum) within an institutional context is a central point at which the preparation of students for their future careers takes place. However, although the necessity for a more efficient and quality preparation, i.e. for the education of future reflexive practitioners, has been constantly emphasised, no significant progress has been achieved so far. Even now, there still exist a misunderstanding about and mistrust of methodical concepts of experiential, problem, group and collaborative teaching upon which the integrated and reflexive approach to education is based. The subject of the research which is presented here is the development and testing of the new course Integrative practice and determining its contribution to professionalisation of future pre-school teachers. It is a one-semester course (taking place during the sixth semester) which can briefly be described as an attpempt at realisation of an integrated teaching process by means of practical training of students. On the one hand, the research is a part of an effort to develop modern strategic approaches to teaching relating to integrated learning and education of students as creators of an integrated approach in a pre-school institution, as well as the researchers of real learning processes and knowledge construction through a project-based approach to working with pre-school children. On the other hand, the research aims at discovering and exploring the characteristics of education of future pre-school teachers with respect to a reflexive practice, which is to contribute to their development as future reflexive practitioners. Starting from the sample comprising sixty students – attendees of the course Integrated practice, the main aim was to explore to which extent the course contents and the manner of its organisation contribute to the development of students, i.e. to future pre-school teachers as reflexive practitioners. The results of the research point to several general conclusions relating to implicit theories of students reflecting their understanding of children, pre-school teachers, teachers, and teaching and learning processes. The first conclusion shows that there are two different viewpoints (of the examined issues), two different images – the explicit and the implicit which mix and build upon each other, depending on the applied technique. Namely, the answers in the questionnaire suggest the beliefs which are closer to modern scientific findings (which focus on children and learning, on the idea of a pre-school teacher/teacher as a partner and a collaborator, on learning as a process of exchange), while those answers which have been given in a form of drawings are closer to traditional approaches (according to which a child is the greatest value, the object of love, a helpless creature depending on the care od the adults; the pre-school teacher is a role model, a provider of knowledge, someone who takes care of children, a second parent; a teacher is a model, an authority). The answers on teaching and learning are mostly constructivist-oriented and point to a transactional model of teaching. The analysis of the standpoints regarding teaching and learning revealed that students have high regard for the importance of the orientation towards a child, which testifies to the departure from their beliefs regarding the role of a pre-school teacher and a child depicted in the analysed drawings. However, the behaviour of students is more closer to the answers given in a form of drawings (to their implicit theories)..

Retrograde p-well for 10kV-class SiC IGBTs

In this paper, we propose the use of a retrograde doping profile for the p-well for ultrahigh voltage (>10 kV) SiC IGBTs. We show that the retrograde p-well effectively addresses the punchthrough issue, whereas offering a robust control over the gate threshold voltage. Both the punchthrough elimination and the gate threshold voltage control are crucial to high-voltage vertical IGBT architectures and are determined by the limits on the doping concentration and the depth that a conventional p-well implant can have. Without any punchthrough, a 10-kV SiC IGBT consisting of retrograde p-well yields gate threshold voltages in the range of 6-7 V with a gate oxide thickness of 100 nm. Gate oxide thickness is typically restricted to 50-60 nm in SiC IGBTs if a conventional p-well with 1×10 17 cm -3 is utilized. We further show that the optimized retrograde p-well offers the most optimum switching performance. We propose that such an effective retrograde p-well, which requires low-energy shallow implants and thus key to minimize processing challenges and device development cost, is highly promising for the ultrahigh-voltage (>10 kV) SiC IGBT technology