PROCAMPO,the Mexican corn market,and Mexican food security

PROCAMPO (Program for Direct Assistance in Agriculture or Programa de Apoyos Directos al Campo) is an income transfer payment to Mexican farmers that compensates them for subsidies received by foreign competitors. Corn (Zea mays) has received the largest amount of PROCAMPO payments and is the primary component of Mexico’s food and feed supply. Results of a spatial and temporal model show that without PROCAMPO, Mexican annual average corn production would have been lower and corn imports would have been 40.5% higher in 2005–2007. Increased producer and consumer surplus and savings from reduced imports reveal that the benefits of PROCAMPO were higher than the program’s costs. Greater PROCAMPO support would decrease Mexican corn imports and increase domestic corn production. It is recommended that PROCAMPO payments to corn producers be continued and increased in the interest of Mexican national food security.     

The development of the child's concept of the family.

60 kindergartners and 2nd and 4th graders, and 20 university students were questioned concerning their ideas about the structure of the family. Information was gathered on which persons children consider to be members of their own families, how a typical family is conceptualized, and what criteria are used in judging whether a grouping of people represents a family. In considering their own families and in constructing typical families, no age differences were found. A nuclear family grouping was most salient in both cases, and all Ss constructed similar typical families that consisted of 2 parents and their children. Major age-related differences were apparent in the criteria adopted for classifying groupings as instances of a family. Living together, contact between members, the presence of children, single parenthood, blood or legal relationship, and same-sex vs cross-sex partners were variables that were of differing importance as criteria for the respondents in the 4 age groups. Basically, the youngest Ss relied on common residence and contact between members as the criteria for evaluating families, whereas, with increasing age, emphasis was placed on blood or legal relationship. Continuities and discontinuities in the development of the concept of the family, comparisons with the development of other concepts, and implications for the child's understanding of the process of divorce or separation are discussed. (French abstract) (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Social Support Among Veterans With Multiple Sclerosis.

Objective: To describe perceived social support and its correlates among veterans with multiple sclerosis (MS) and explore gender differences in these relationships. Study Design: Cohort study linking computerized medical records and survey questionnaire. Participants: Four hundred fifty-one veterans. Outcome Measure: Total and subscale scores from the Medical Outcomes Study Modified Social Support Survey. Results: Participants who were male, married, living with someone, and/or had a relapsing-remitting disease course reported greater social support. Married men reported higher levels of 4 of 5 types of support than married women. Higher income was associated with greater total social support for women. Conclusion: Although veterans with MS report moderate total support, the authors recommend support-enhancing interventions tailored by gender and marital status. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Influence of freezing and freezing plus acidic calcium sulfate and lactic acid addition on thermal inactivation of Escherichia coli O157:H7 in ground beef

Undercooked ground beef is a leading vehicle for acquiring Escherichia coli O157:H7 infections through consumption of foods. Studies have been performed to determine the effect of freezing and the combined effect of freezing and addition of a mixture of 20% acidic calcium sulfate (final concentration of 0.4% in ground beef) and 10% lactic acid (final concentration of 0.2% in ground beef) (ACS-LA) on the thermal sensitivity of E. coli O157:H7 in ground beef. Five strains of E. coli O157: H7 were separately inoculated into ground beef and held at 5 degrees C for up to 10 days or -20 degrees C for up to 3 weeks then heated at 57, 60, 62.8, 64.3, and 68.3 degrees C to determine rates of thermal inactivation. Results revealed that D-values (decimal reduction times) at equivalent temperatures for four of five E. coli O157:H7 strains were less in the previously frozen than in the refrigerated ground beef and that strains isolated from ground beef in 1993 and 1994 were generally more sensitive to thermal inactivation than those isolated in 1999 and 2000. Only one strain of E. coli O157:H7 was used to determine the effect of ACS-LA in previously frozen or refrigerated ground beef on rates of thermal inactivation. The addition of ACS-LA to ground beef at 20 ml/kg increased the thermal sensitivity of E. coli O157:H7 in both previously frozen and refrigerated ground beef, with greatest rates of inactivation occurring in previously frozen ground beef containing ACS-LA. D-values at 57 degrees C obtained for E. coli O157:H7 in previously refrigerated and frozen ground beef containing ACS-LA and ACS-LA diluted by half were significantly (P < 0.05) less than those obtained in ground beef with no ACS-LA added. D-values at 60 and 62.8 degrees C were consistently less in ACS-LA treated ground beef, but for most treatments the results were not significantly (P > 0.05) different than the controls. Results revealed that the addition of ACS-LA to ground beef, whether frozen or refrigerated, can reduce the temperature or time required to kill E. coli O157:H7 during heating.     

Using Remotely Sensed Imagery to Detect Urban Change: Viewing Detroit from Space

The data integration capabilities of Geographic Information Systems (GIS) are providing new opportunities for urban analysis. This article describes the work of a multidisciplinary team who used spatial data from NASA's Landsat earth observation satellite to analyze the net vegetation change between 1975 and 1992 in Detroit, Michigan. Furthermore, by integrating the satellite-derived change data with census data from 1970, 1980, and 1990, this research shows how the extensive demographic changes that occurred in Detroit over the past quarter century have resulted in physical landscape changes detectable from space. Strong correlations were found between the patterns of social, economic, and demographic data and the pattern of vegetation change seen in the satellite imagery, both for certain points in time and changes over time. These correlations suggest that the imagery reflects processes of urban growth, inner-city decline, population shifts, and change in urban form.     

Job scheduling to minimize expected weighted flowtime on uniform processors

We consider a sequencing problem in which there are n jobs to be processed nonpreemptively on m nonidentical processors. The processing time of the j-th processor is exponentially distributed with rate μ_j, where μ₁μ₂μ_m. Job i incurs a holding cost at rate c_i per unit time while still in the system, where c₁c₂c_n. We show that to minimize total expected holding costs (weighted flowtime), it is optimal to take the fastest (lowest indexed) available processor, say processor j, and assign job k to it if k>(Σ_i^j−₁μ_i)/μ_j−j k−1. After each assignment the jobs are renumbered (so that job k+1 becomes job k, etc.), and the procedure is repeated with the next fastest available processor, etc. Note that the policy does not depend on the values of the holding costs c_i. This result is a generalization of the result of Agrawala et al. (1984) for minimizing expected flowtime, i.e., minimizing total holding cost when the holding costs of all the jobs are the same. We give a simpler proof of the more general result.     

IN‐Tune: an In‐Situ non‐invasive performance tuning tool for multi‐threaded Linux on symmetric multiprocessing Pentium workstations

This paper documents the design and implementation of the IN‐Tune software tool suite, which enables a user to collect real‐time code and hardware profiling information on Intel‐based symmetric multiprocessors running the Linux operating system. IN‐Tune provides a virtually non‐invasive tool for performance analysis and tuning of programs. Unlike other analysis tools, IN‐Tune isolates data with respect to individual threads. It also utilizes performance monitoring hardware registers to permit instrumentation of individual threads as they run in‐situ, thus collecting data with appropriate considerations for a multiprocessor environment. Data can be sampled using two different mechanisms. First, the user can collect data by making calls to the system upon the occurrence of specific software events. Secondly, data can be collected at a fixed, fine grain (e.g. 1–10 microseconds) interval using either software or hardware interrupts. To allow observation of codes for which source code modification is impractical or impossible, a ‘shell’ task is created which permits monitoring without code modification. Although this work deals with Intel processors and Linux, the widespread availability of performance monitoring registers in modern processors makes this work widely applicable. Copyright © 1999 John Wiley & Sons, Ltd.     

A meta-rule approach to flexible plan recognition in dialogue

Although a number of researchers have demonstrated that reasoning on a model of the user's plans and goals is helpful in language understanding and response generation, current models of plan inference cannot handle naturally occurring dialogue. This paper argues that model building from less than ideal dialogues has a great deal in common with processing ill-formed input. It defines well-formedness constraints for information-seeking dialogues and contends that strategies for interpreting ill-formed input can be applied to the problem of modeling the user's plan during an ill-formed dialogue. It presents a meta-rule approach for hypothesizing the cause of dialogue ill-formedness, and describes meta-rules for relaxing the plan inference process and enabling the consideration of alternative hypotheses. The advantages of this approach are that it provides a unified framework for handling both well-formed and ill-formed dialogue, avoids unnatural interpretations when the dialogue is proceeding smoothly, and facilitates a nonmonotonic plan recognition system.Rhonda Eller is a Ph.D. candidate in Computer Science at the University of Delaware. She received her B.S. in Computer Science from Millersville University of Pennsylvania in 1987, and her M.S. degree in the same field from the University of Delaware. Her primary interests lie in the areas of natural language processing, plan recognition, and user modelling. This paper summarizes the current state of her thesis work on repair of an incorrectly inferred plan for a user.Sandra Carberry is an associate professor of computer science at the University of Delaware. Her research interests include discourse understanding, user modeling, planning and plan recognition, and intelligent natural language interfaces. This paper describes work that is part of an ongoing research project to develop a robust model of plan recognition.     

College students with physical disabilities: Myths and realities.

Examined (1) the affect concerning interaction between nondisabled (ND) college students and physically disabled (PD) students, (2) stereotyping by both ND and PD students, (3) aspects of the self-concepts of ND and PD students, (4) ND students' beliefs about these aspects of self-concept. 32 PD college students (aged 19–36 yrs) and 221 ND students served as Ss. Data from a battery of measures showed that ND Ss were less comfortable with PD peers than with able-bodied peers. PD Ss were equally comfortable with ND individuals and with those having the same disability as they did but were as uncomfortable as ND Ss with peers having a disability different from their own. When predicting the responses of others, ND Ss scored both able-bodied and PD peers lower on most dimensions of self-concept than the actual scores of these groups indicate. (PsycINFO Database Record (c) 2010 APA, all rights reserved)