Effects of nutrient enrichment on freshwater macrophyte and invertebrate abundance: A meta-analysis.

External nutrient loading can cause large changes in freshwater ecosystems. Many local field and laboratory experiments have investigated ecological responses to nutrient addition. However, these findings are difficult to generalize, as the responses observed may depend on the local context and the resulting nutrient concentrations in the receiving water bodies.

Prevalence of obstructive sleep apnea at an outpatient memory clinic.

Objectives: Obstructive sleep apnea (OSA) is a common sleep disorder that has several health hazards, including cognitive dysfunction. Studies have thus far primarily focussed on the prevalence of cognitive impairment in patients diagnosed with OSA at sleep clinics. The present study aims to investigate the prevalence of OSA at an outpatient memory clinic.

Object-oriented image analysis for high content screening: detailed quantification of cells and sub cellular structures with the Cellenger software.

Background: Detailed image analysis still is a considerable bottleneck for many cellular assays, and automated solutions to the problem are desirable. However, dealing with the complexity and variability of structures in cellular images makes detailed and reliable analysis a nontrivial task.

Methods: Therefore, based on the object-oriented image analysis approach, a novel image analysis technology, a flexible and reliable system for image analysis in cellular assays was developed.

Client satisfaction with service delivery of assistive technology for outdoor mobility.

Purpose: In the decentralized Dutch service delivery system, client satisfaction levels for the provision of assistive technology (AT) for outdoor mobility for elderly and disabled persons was measured to investigate whether or not differences exist between local service delivery systems and if so, how these can be explained.

Method: In June 1999 a postal questionnaire was sent to a random sample of 973 adult users from three local authorities who had received their AT in 1998. Client satisfaction with the service delivery process was measured using seven items (alpha=0.

Specific detection of chikungunya virus using a RT-PCR/nested PCR combination.

Chikungunya (CHIK) virus is enzootic in many countries in Asia and throughout tropical Africa. In Asia the virus is transmitted from primates to humans almost exclusively by Aedes aegypti, while various aedine mosquito species are responsible for human infections in Africa. The clinical picture is characterized by a sudden onset of fever, rash and severe pain in the joints which may persist in a small proportion of cases.

Development of reverse transcription-PCR assays specific for detection of equine encephalitis viruses.

Specific and sensitive reverse transcription-PCR (RT-PCR) assays were developed for the detection of eastern, western, and Venezuelan equine encephalitis viruses (EEE, WEE, and VEE, respectively). Tests for specificity included all known alphavirus species. The EEE-specific RT-PCR amplified a 464-bp region of the E2 gene exclusively from 10 different EEE strains from South and North America with a sensitivity of about 3,000 RNA molecules.