Urban and agricultural soils: conflicts and trade-offs in the optimization of ecosystem services

On-going human population growth and changing patterns of resource consumption are increasing global demand for ecosystem services, many of which are provided by soils. Some of these ecosystem services are linearly related to the surface area of pervious soil, whereas others show non-linear relationships, making ecosystem service optimization a complex task. As limited land availability creates conflicting demands among various types of land use, a central challenge is how to weigh these conflicting interests and how to achieve the best solutions possible from a perspective of sustainable societal development. These conflicting interests become most apparent in soils that are the most heavily used by humans for specific purposes: urban soils used for green spaces, housing, and other infrastructure and agricultural soils for producing food, fibres and biofuels. We argue that, despite their seemingly divergent uses of land, agricultural and urban soils share common features with regards to interactions between ecosystem services, and that the trade-offs associated with decision-making, while scale- and context-dependent, can be surprisingly similar between the two systems. We propose that the trade-offs within land use types and their soil-related ecosystems services are often disproportional, and quantifying these will enable ecologists and soil scientists to help policy makers optimizing management decisions when confronted with demands for multiple services under limited land availability.     

Analysis of the non-native flora of Ensenada, a fast growing city in northwestern Baja California

Urbanized areas show a high proportion of non-native plants and can work as dispersal points to the surrounding areas. Ensenada is a fast growing city located in the northwestern peninsula of Baja California (Mexico). It is the southern extreme of a bi-national, coastal urban corridor that extends from Los Angeles, California south to Ensenada. This corridor is part of the biodiversity hotspot of the California Floristic Province. The aim of this study was to analyze the composition and distribution of the spontaneous flora in the city of Ensenada. We systematically sampled two differentiated urban environments, vacant lots and arroyos, in 2006 and 2007. We found a total of 158 plant species, 61% of them were non-native species. Arroyo areas showed higher non-native species richness than vacant lots (21.9 vs. 13.6 species/transect) and could be potential dispersal vectors for non-native species to natural areas outside of the city, or in the reverse direction also.     

Accuracy of approximate progressively censored reliability sampling plans for exponential models

Reliability sampling plans provide an efficient method to determine the acceptability of a product based upon the lifelengths of some test units. Usually, they depend on the producer and consumer’s quality requirements and do not admit closed form solutions. Acceptance sampling plans for one- and two-parameter exponential lifetime models, derived by approximating the operating characteristic curve, are presented in this paper. The accuracy of these approximate plans, which are explicitly expressible and valid for failure and progressive censoring, is assessed. The approximation proposed in the one-parameter case is found to be practically exact. Explicit lower and upper bounds on the smallest sample size are given in the two-parameter case. Some additional advantages are also pointed out.     

Using nursing students to enhance one college's immunization program.

In New York State, all college students who were born on or after January 1, 1957, are required to show proof of immunity against measles, mumps, and rubella (MMR) before the 1st day of classes. Colleges have established immunization programs so that those students who do not have the required proof can be given the necessary injections. Often, our health service office does not have enough staff to administer the MMR shots during the registration period, resulting in long lines of students waiting to be immunized. In this article, the authors describe how one college used nursing students to assist with and enhance its immunization program. The 45 nursing students who participated in this project administered 694 injections over a 5-day period, They received credit from the nursing department for clinical time and all of the participants agree that the project was a success.     

Extension of the pool-adjacent-violators algorithm

The pool-adjacent-violators algorithm (PAVA) is an efficient algorithm which converges in a finite number of steps. However, it has been applicable so far only in isotonic regression with the simple order. This report extends its applicability to other quadratic programming problems, including certain one-sided multivariate testing problems and concave regression problems.     

Evaluation in the Social Studies

Online role-playing games such as World Of Warcraft represent new participatory cultures in which today's students engage every day. They are appealing to players largely because of the social aspects of game play. Some features of massively multiplayer online role-playing games (MMORPGs) can be incorporated into classroom culture to create more dynamic interactions between students and improve both content instruction and civic competence.     

Ridge estimation of restricted parameters in production techniques

The problem of determining ridge estimates of the regression parameters in a two-input production function model,constrained to be non-negative,has been formulated as an exercise in quadratic programming. Relevant Kuhn-Tucker conditions have been derived and a small simulation studv has been carried out.     

On gart's test for interaction of second order

Gart (1972) ottered a Statistic on testing the hypothesis of no second-order interaction in a 2×s×t contingency table. The statistic was tn be used as an asymptotic chi-square with (s-1) (t-1) degrees of freedom. We show that this statistic suiters from the drawback that unless certain side conditions hold, the statistic would reject the null hypothesis with probability approaching one asymptotically even in the null case. Hence the statistic is not strictly valid for the hypothesis for which it was intended.     

Men,Gender, and Health: Toward an Interdisciplinary Approach

Abstract

The anatomy and physiology of the ears, nose, and sinuses are reviewed. Diseases and injuries typically associated with water sports are discussed, with emphasis on pathophysiology, treatment, and preventative measures.

“Screening for Chlamydial Infections in Women Attending Family Planning Clinics: Evaluation of Presumptive Indicators for Therapy,” JULIUS SCHACHTER, EILEEN STONER, and JEANNE MONCADA. Chlamydia trachomatis was recovered from the cervices of 9.8 percent (268/2,729) of women attending seven family planning clinics. The infection rate varied from 5.5 percent to 22.5 percent in different clinics. Chlamydial infection could be associated with younger age, nulliparity, being black and use of oral contraceptives. Most (70 percent) of the chlamydial infections were inapparent and presumptive indicators for antichlamydial therapy that are useful for symptomatic women will not make a major impact on this reservoir. It is concluded that chlamydial cultures are needed to deal with the high prevalence of these infections. (Western Journal of Medicine 1983 Mar;138:375–379.)