Does habitat loss affect the communities of plants and insects equally in plant–pollinator interactions? Preliminary findings

Habitat loss is a major threat to biodiversity and ecosystem function. As habitats are lost, one factor affecting their community structures is the niche-width demand of species, which ranges from specialist to generalist. This study focused on specialist and generalist species in plant–pollinator interactions and tested the hypothesis that plant and pollinator communities become more generalized as habitat loss increases. The study was made in seven selected sites in southern Ontario, Canada, at the level of landscape that is characterized by distributed forests within intensively managed agricultural fields. We quantified both the degree of habitat loss and the degree of specialization/generalization for each of the plant and insect communities using a sampling method of hexagonal transects. Regression analysis indicated a significant relationship between the increase of habitat loss and the shift to generalization in insect, but not in plant, communities. Our results suggest that, in plant–pollinator interactions, insect communities are more sensitive and/or quicker than plant communities to respond to the effects of habitat loss.     

Patient characteristics that may predict the likelihood of the presence of mental health problems in patients attending the general outpatient clinic of a tertiary hospital in South-South Nigeria

Background A considerable number of patients seen in general outpatient clinics (GOPC) are known to suffer from psychiatric rather than physical disorders. Studies have shown that doctors working in these clinics have difficulty in making accurate ratings of mental health problems in their patients and have poor knowledge of psychiatric diagnosis. Accurate recognition of psychiatric symptoms in a patient is essential for specific diagnosis and successful management. There is a need for the use of an easy tool such as the12-item General Health Questionnaire (GHQ-12) for screening and identification of psychopathologies especially in a busy clinic setting like the GOPC. Aside from psychometric screening tools, patients' sociodemographic characteristics such as gender, age, marital status, occupation, education etc. have been found to be of value in predicting those at risk.Objectives This study seeks to correlate GHQ 'caseness' with sociodemographic factors and to compare physician diagnosis with GHQ diagnosis.Subjects and method Three-hundred and twenty-two respondents were recruited for the study by a systematic random sampling method. Using a cut off score of three on both the English and Efik translation versions of the GHQ-12, 'cases' and 'non-cases' generated were compared with the same classification as identified by the GOPC doctors. Identification rates for both groups were calculated and the coefficients determined using a two-by-two contingency table. Sociodemographic correlates were determined by statistical comparison of the classifications in both groups.Results Statistically significant differences in sociodemographic characteristics of respondents were found for age (χ(2)=48.97; P <0.05) and education (χ(2)=45.64; P=0.05) using their GHQ-12 scores, and for occupation (χ(2)=37.90; P <0.05) among those seen by the GOPC doctors. A further comparison of identified 'cases' and 'non-cases' by doctors again revealed significant difference for age (χ(2)=7.151; P <0.05). Sex as a sociodemographic characteristic showed no statistically significant difference though a greater percentage of females (57.3%) were observed as 'high scorers' as compared to their male counterparts (42.7%). The GHQ-12 identified 46.6% 'cases' while the GOPC doctors identified 6.8% among the attendees with a diagnostic sensitivity of 8% and a specificity of 94%, respectively.Conclusion Belonging to the 18-39 years age group, being employed and having less than 12 years of education were the patients' characteristics that suggested the likelihood of the presence of mental health problems.This study also revealed that despite the high proportion of psychiatric morbidity (46.6%) in the GOPC of the University of Calabar Teaching Hospital (UCTH) rate of detection by the clinic doctors was low (6.8%).It is recommended that primary care doctors should be alerted to the possibility that clinically significant psychiatric morbidity may be present in GOPC attendees. The correlation between patients' sociodemographic parameters and presence of mental health problems could be informative and should be given adequate attention during consultation.     

Depression comorbidity among patients with tuberculosis in a university teaching hospital outpatient clinic in Nigeria

Background Tuberculosis (TB) remains a leading infectious cause of morbidity and mortality throughout the world. Medication non-compliance has been recognised as one of the drawbacks in the successful management of this disease. Hence, different approaches for ensuring medication compliance have been adopted; these include the Directly Observed Therapy Short course (DOTS). TB is associated with psychiatric morbidity, particularly depressive disorder, and this has been recognised as a cause of poor compliance and a cause of increased morbidity and mortality from the disease. Despite this recognition, little attention is paid to the identification of depression among TB patients, particularly in the DOTS clinics that most of these patients attend. This study was designed to determine the prevalence of depression in patients with TB attending the DOTS outpatient clinic in a university teaching hospital in Nigeria, and to find out the factors that may be associated with this.Method All consenting TB patients attending the clinic completed a socio-demographic questionnaire and nine-item Patient Health Questionnaire (PHQ-9) designed to screen for depression, especially in outpatient and primary care settings.Results Sixty-five patients participated in the study of whom 41 (63.1%) were males. The mean age of the respondents was 35.1 ± 14.4 (range 15-70 years). Eighteen (27.7%) of the patients had depression, comprising 14 (21.5%) with mild depression and four (6.2%) with moderate depression. Socio-demographic factors (age groups, P=0.024; and financial status, P=0.02) and a clinical factor (persistent cough, P=0.04) were significantly associated with depression.Conclusion Measures to reduce depression among patients with TB should include effective symptom control, particularly of coughing, and measures to improve the financial status of this group of patients. Financial empowerment of patients may reduce depression in them, improve the compliance rate to anti-TB medication, and could furthermore bring an improvement to their quality of life.     

One-year mortality after a first visit to a cardiology outpatient clinic: a useful performance indicator?

Purpose In 2003 the Dutch Health Care Inspectorate introduced performance indicators to monitor and compare quality of care in Dutch hospitals. In 2007, the new performance indicator ‘one-year mortality after a first visit to a cardiology outpatient clinic’ was introduced. We set out to evaluate this new indicator in three Dutch teaching hospitals. Methods Using electronic medical records, information was collected retrospectively of patients aged ≥70 years who visited the cardiology outpatient clinic of Medical Centre Alkmaar, Meander Medical Centre Amersfoort and Deventer Hospital between 1 January 2006 and 31 January 2006. Diagnoses were based on the diagnosis treatment combination (DBC) coding system. Results 547 patients (mean age 78.0 years, 53% men) were included, 35 (6.4%) of whom had died after one year. Cardiovascular disease was the most frequent cause of death (22/35, 62.9%). The oneyear mortality among the three hospitals varied from 5.0 to 7.3% (NS). Conclusion One-year mortality after the first visit to a cardiology outpatient clinic amounted to 6.4% in patients aged ≥70 years and did not differ significantly between the three Dutch teaching hospitals. The administrative load to obtain the necessary information was considerable. One-year mortality should be regarded as an ‘outcome’ parameter rather than a ‘performance’ indicator. (Neth Heart J 2009;17:52-5.)     

Meta-analysis of survey data to assess trends of prairie butterflies in Minnesota, USA during 1979–2005

During 1993–1996, two teams (Schlicht, Swengels) surveyed the same Minnesota prairies, but without any coordination of sites, routes, methods, dates, and results between teams. In 27 instances, both teams surveyed the same site in the same year between 30 June and 18 July. For the 18 most frequently recorded species, abundance indices (individuals/h per site) significantly covaried between teams for 11 (61%) species, including 2/3 prairie specialists tested. No species significantly correlated negatively, 17/18 species had positive correlations, and the preponderance of positive correlations was significant. Swengel indices per hour (two surveyors; unlimited-width transect) averaged 2.42 times Schlicht indices (one surveyor; fixed-width transect). These results demonstrate that transect surveys by different teams at the same sites but not the same routes produce similar rankings of species abundance among sites. This approach to population monitoring (transect surveys during the season that covers the most specialist species at once, not necessarily with fixed routes but recording all species seen) might also be appropriate in other regions with high habitat loss and low human population density. Abundance indices from surveys by seven teams spanning 1979–2005 were calculated for evaluating population trends. For the five analyzable specialist species, 25/30 population trend tests of a species at a site had a negative direction, a highly significant skewing (P < 0.0001). By contrast, five “common” (most frequently recorded non-specialist) species had an even distribution of negative and positive trends. While adjacent sites had similarly timed decline thresholds (last year when a higher rate or any individual was recorded vs. first year when all subsequent indices were lower or zero) within species, these thresholds were not synchronized among sites in different counties. All sites analyzed in this study were preserves managed primarily with fire. While the ecosystem (or vegetative) approach to reserve selection has been validated in other studies to be effective at capturing populations of associated specialist butterflies, butterfly declines after reserve designation will likely continue unless the ecosystem approach to reserve management includes specific consideration of individual butterfly species’ required resources and management tolerances.     

Food preference and performance of the larvae of a specialist herbivore: variation among and within host-plant populations

Specialist herbivores are suggested to be unaffected by or attracted to the defense compounds of their host-plants, and can even prefer higher levels of certain chemicals. Abrostola asclepiadis is a specialist herbivore whose larvae feed on the leaves of Vincetoxicum hirundinaria, which contains toxic alkaloids and is unpalatable to most generalist herbivores. The food choice, leaf consumption and growth of A. asclepiadis larvae were studied to determine whether there is variation among and within host-plant populations in their suitability for this specialist herbivore. There was significant variation in food preference and leaf consumption among host-plant populations, but no differences were found in larval growth and feeding on different host-plant populations. A. asclepiadis larvae preferred host-plant populations with higher alkaloid concentrations, but did not consume more leaf material from plants originating from such populations in a no-choice experiment. There was also some variation in food preference of larvae among host-plant individuals belonging to the same population, suggesting that there was variability in leaf chemistry also within populations. Such variation in larval preference among host-plant genotypes and populations may create potential for coevolutionary dynamics in a spatial mosaic.     

塑造妇幼保健院智慧门诊的设想与探索

基于“云”“大”“物”“移”“智”信息技术，提出了妇幼保健智慧门诊的设想，对以信息集成平台为基础，由五大业务应用系统组成的智慧门诊信息系统构架进行了阐述，讨论了在预约挂号、就诊检查、诊间结算、充值缴费、结果的单次门诊就诊闭环中优化流程、提高效率、改善就医体验等方面的方法。     

Experimental infections of the monogenean Gyrodactylus turnbulli indicate that it is not a strict specialist

Parasites represent a threat to endangered fish species, particularly when the parasite can host switch and the new host is vulnerable. If the parasite is highly host specific then successful host switching should be a rare occurrence; however, the host range of many parasites which are assumed to be specialists has never been tested. This includes the monogenean Gyrodactylus turnbulli, a well-studied ectoparasite found caudally on its known host, the guppy, Poecilia reticulata. In this study, we monitored parasite establishment and reproduction on a range of poeciliids and more distantly related fish. Individually maintained fish were experimentally infected with a single parasite and monitored daily to establish whether G. turnbulli could survive and reproduce on other fish species. Gyrodactylus turnbulli can infect a wider range of hosts than previously considered, highlighting the fact that host specificity can never be assumed unless experimentally tested. Our findings also have significant implications for parasite transmission to novel hosts and provide further insight into the evolutionary origins of this ubiquitous group of fish pathogens. Previous molecular evidence indicates that host switching is the key mechanism for speciation within the genus Gyrodactylus. Until recently, most Gyrodactylus spp. were assumed to be narrowly host specific. However, our findings suggest that even so-called specialist species, such as G. turnbulli, may represent a threat to vulnerable fish stocks. In view of the potential importance of host switching under artificial conditions, we propose to describe this as 'artificial ecological transfer' as opposed to 'natural ecological transfer', host switching under natural conditions.     

A resolution of the paradox of enrichment

Theoretical studies have shown a paradoxical destabilizing response of predator-prey ecosystems to enrichment, but there is the gap between the intuitive view of nature and this theoretical prediction. We studied a minimal predator-prey system (a two predator-two prey system) in which the paradox of enrichment pattern can vanish; the destabilization with enrichment is reversed, leading to stabilization (a decrease in the amplitude of oscillation of population densities). For resolution of the paradox, two conditions must be met: (1) the same prey species must be preferred as a dietary item by both predator species, creating the potential for high exploitative competition between the predator species, and (2), while both predators are assumed to select their diet in accordance with optimal diet utilization theory, one predator must be a specialist and the other a generalist. In this system, the presence of a less profitable prey species can cause the increase in population oscillation amplitudes associated with increasing enrichment to be suppressed via the optimal diet utilization of the generalist predator. The resulting stabilization is explained by the mitigating effect of the less profitable prey showing better population growth with increasing enrichment on the destabilization underlying the specialist predator and prey relation, thus resolving the paradox of enrichment.