A SYSTEM DYNAMICS MODEL OF AGRICULTURE AND RURAL DEVELOPMENT: THE TOPMARD CORE MODEL

The goal of the TOPMARD project is to develop a model of agriculture and rural development to better understand the agronomic, ecological, economic and social dimensions of rural regions. The resulting model, (Policy Model of Multifunctional Agriculture and Rural Development) was built collaboratively and hierarchically by the research teams from the 11 countries. The model features eight subsectors (Land, Agriculture, Tourism, Region, Human Resources, Non-commodities, Capital, and Quality of Life). Imbedded in the model are a complete dynamic input-output model, and an agecohort education demographic model. The model has both supply-side and demand-side drivers. Land use is the key supply-side driver. Land use, coupled with production system choices, determine agricultural and non-commodity outputs. The Quality of Life sector incorporates the coefficients from a regression analysis of migration behaviour to develop a supply-side population response to local quality of life which is added to the demand-side response to job growth.Multifunctionality, system dynamics, policy, model, rural development, Community/Rural/Urban Development, Research Methods/ Statistical Methods, Research and Development/Tech Change/Emerging Technologies,

Seasonal Abundance of Autotrophic Picoplankton in the Pagan River, a Nutrient Enriched Subestuary of the James River, Virginia

Autotrophic picoplankton had average monthly concentrations of 73.5 X 106 cells/L in the Pagan River, with summer-early fall maxima of 108 cells/L. The abundance peaks increased with rising water temperatures, declining to their least abundance in mid-winter (105 cells/L)

Student Misbehaviors, Instructor Responses, And Connected Classroom Climate: Implications for the Basic Course

The concept of connected classroom climate focuses on student-to-student communication behaviors that are paramount in creating the climate of a class, especially in the basic course. While previous studies have focused on the positive and cooperative behaviors of students and instructors that may contribute to perceptions of classroom connectedness, the role that incivilities may play in detracting from or undermining a connected classroom climate has not been investigated. This study examines perceptions of a connected classroom climate and its relationships to student misbehaviors and instructor responses. A total of 542 university students enrolled in 30 sections of the basic public speaking course completed the Connected Classroom Climate Inventory (CCCI) and scales measuring student misbehaviors and teacher responses to student misbehaviors. Results showed that student perceptions of a connected classroom climate were inversely related to both inconsiderate and harassing student misbehaviors. The results also revealed a possible relationship between classroom connectedness and the manner in which instructors respond to students when they misbehave. These findings suggest that basic course instructors need to consider how to reduce student inconsideration and harassment misbehaviors in their classes, and how to positively respond to these behaviors when they do occur so that classroom connectedness is not diminished

Connected Classroom Climate and Communication in the Basic Course: Associations with Learning

Most research on the association between classroom climate and student learning has emphasized the instructor’s role in creating a positive learning environment. However, the role students play in fostering a classroom climate that promotes learning has received less attention, particularly in the basic course. This study examined the relationship between perceptions of a connected classroom climate and students’ cognitive and affective learning involving 437 freshman and sophomore university students enrolled in the basic public speaking course. Students completed the Connected Classroom Climate Inventory (CCCI) and scales measuring affective and cognitive learning. Results showed significant relationships between student perceptions of connected classroom climate and cognitive learning, affective learning, and affective behavioral intent

Optimal refrigerator

We study a refrigerator model which consists of two $n$-level systems interacting via a pulsed external field. Each system couples to its own thermal bath at temperatures $T_h$ and $T_c$, respectively ($\theta\equiv T_c/T_h<1$). The refrigerator functions in two steps: thermally isolated interaction between the systems driven by the external field and isothermal relaxation back to equilibrium. There is a complementarity between the power of heat transfer from the cold bath and the efficiency: the latter nullifies when the former is maximized and {\it vice versa}. A reasonable compromise is achieved by optimizing the product of the heat-power and efficiency over the Hamiltonian of the two system. The efficiency is then found to be bounded from below by $\zeta_{\rm CA}=\frac{1}{\sqrt{1-\theta}}-1$ (an analogue of the Curzon-Ahlborn efficiency), besides being bound from above by the Carnot efficiency $\zeta_{\rm C} = \frac{1}{1-\theta}-1$. The lower bound is reached in the equilibrium limit $\theta\to 1$. The Carnot bound is reached (for a finite power and a finite amount of heat transferred per cycle) for $\ln n\gg 1$. If the above maximization is constrained by assuming homogeneous energy spectra for both systems, the efficiency is bounded from above by $\zeta_{\rm CA}$ and converges to it for $n\gg 1$.Comment: 12 pages, 3 figure

Connected Classroom Climate and Communication Apprehension: Correlations and Implications of the Basic Course

Although scholars have recommended increasing relational variables in the classroom such as familiarity, acquaintance level, and collaboration to help students moderate communication apprehension (CA), few, if any, academic studies have investigated the relationship between CA and a supportive climate among students in the college classroom. Self-report data were collected from 523 undergraduate students from a Midwestern university who participated in a large curriculum assessment program using the Connected Classroom Climate Inventory (CCCI) and the PRCA-24. Results showed significant relationships between student perceptions of connected-classroom climate and CA levels throughout the course

Epidemiologic Measures for Quantifying the Incidence of Concussion in National Collegiate Athletic Association Sports

Injury rates compare the relative frequency of sport-related concussions across groups. However, they may not be intuitive to policy makers, parents, or coaches in understanding the likelihood of concussion

The practical implications of using standardized estimation equations in calculating the prevalence of chronic kidney disease

BACKGROUND: Kidney Disease Outcomes Quality Initiative (KDOQI) chronic kidney disease (CKD) guidelines have focused on the utility of using the modified four-variable MDRD equation (now traceable by isotope dilution mass spectrometry IDMS) in calculating estimated glomerular filtration rates (eGFRs). This study assesses the practical implications of eGFR correction equations on the range of creatinine assays currently used in the UK and further investigates the effect of these equations on the calculated prevalence of CKD in one UK regionMETHODS: Using simulation, a range of creatinine data (30-300 micromol/l) was generated for male and female patients aged 20-100 years. The maximum differences between the IDMS and MDRD equations for all 14 UK laboratory techniques for serum creatinine measurement were explored with an average of individual eGFRs calculated according to MDRD and IDMS &lt; 60 ml/min/1.73 m(2) and 30 ml/min/1.73 m(2). Similar procedures were applied to 712,540 samples from patients &gt; or = 18 years (reflecting the five methods for serum creatinine measurement utilized in Northern Ireland) to explore, graphically, maximum differences in assays. CKD prevalence using both estimation equations was compared using an existing cohort of observed data.RESULTS: Simulated data indicates that the majority of laboratories in the UK have small differences between the IDMS and MDRD methods of eGFR measurement for stages 4 and 5 CKD (where the averaged maximum difference for all laboratory methods was 1.27 ml/min/1.73 m(2) for females and 1.59 ml/min/1.73 m(2) for males). MDRD deviated furthest from the IDMS results for the Endpoint Jaffe method: the maximum difference of 9.93 ml/min/1.73 m(2) for females and 5.42 ml/min/1.73 m(2) for males occurred at extreme ages and in those with eGFR &gt; 30 ml/min/1.73 m(2). Observed data for 93,870 patients yielded a first MDRD eGFR &lt; 60 ml/min/1.73 m(2) in 2001. 66,429 (71%) had a second test &gt; 3 months later of which 47,093 (71%) continued to have an eGFR &lt; 60 ml/min/1.73 m(2). Estimated crude prevalence was 3.97% for laboratory detected CKD in adults using the MDRD equation which fell to 3.69% when applying the IDMS equation. Over 95% of this difference in prevalence was explained by older females with stage 3 CKD (eGFR 30-59 ml/min/1.73 m(2)) close to the stage 2 CKD (eGFR 60-90 ml/min/1.73 m(2)) interface.CONCLUSIONS: Improved accuracy of eGFR is obtainable by using IDMS correction especially in the earlier stages of CKD 1-3. Our data indicates that this improved accuracy could lead to reduced prevalence estimates and potentially a decreased likelihood of onward referral to nephrology services particularly in older females.</p