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1.
Sci Rep ; 8(1): 14284, 2018 09 24.
Article in English | MEDLINE | ID: mdl-30250047

ABSTRACT

Using a temporal-dynamic calibrated Ecosim food web model, we assess the effects of future changes on marine resources and ecosystem conditions of the Israeli Mediterranean continental shelf. This region has been intensely invaded by Indo-Pacific species. The region is exposed to extreme environmental conditions, is subjected to high rates of climate change and has experienced intense fishing pressure. We test the impacts of a new set of fishing regulations currently being implemented, a continued increase in sea temperatures following IPCC projections, and a continued increase in alien species biomass. We first investigate the impacts of the stressors separately, and then we combine them to evaluate their cumulative effects. Our results show overall potential future benefits of fishing effort reductions, and detrimental impacts of increasing sea temperature and increasing biomass of alien species. Cumulative scenarios suggest that the beneficial effects of fisheries reduction may be dampened by the impact of increasing sea temperature and alien species when acting together. These results illustrate the importance of including stressors other than fisheries, such as climate change and biological invasions, in an ecosystem-based management approach. These results support the need for reducing local and regional stressors, such as fishing and biological invasions, in order to promote resilience to sea warming.


Subject(s)
Aquatic Organisms/physiology , Climate Change , Ecosystem , Fisheries , Introduced Species , Oceans and Seas , Biomass , Mediterranean Region , Statistics, Nonparametric
2.
Sci Rep ; 7(1): 13438, 2017 10 18.
Article in English | MEDLINE | ID: mdl-29044134

ABSTRACT

An integrated ecosystem model including fishing and the impact of rising temperatures, relative to species' thermal ranges, was used to assess the cumulative effect of future climate change and sustainable levels of fishing pressure on selected target species. Historically, important stocks of cod and whiting showed declining trends caused by high fisheries exploitation and strong top-down control by their main predators (grey seals and saithe). In a no-change climate scenario these stocks recovered under sustainable management scenarios due to the cumulative effect of reduced fishing and predation mortalities cascading through the food-web. However, rising temperature jeopardised boreal stenothermal species: causing severe declines in grey seals, cod, herring and haddock, while eurythermal species were not affected. The positive effect of a higher optimum temperature for whiting, in parallel with declines of its predators such as seals and cod, resulted in a strong increase for this stock under rising temperature scenarios, indicating a possible change in the contribution of stocks to the overall catch by the end of the century. These results highlight the importance of including environmental change in the ecosystem approach to achieve sustainable fisheries management.


Subject(s)
Biomass , Fisheries , Global Warming , Animals , Behavior, Animal , Biodiversity , Fishes/physiology , Oceans and Seas
3.
Proc Biol Sci ; 283(1844)2016 12 14.
Article in English | MEDLINE | ID: mdl-27928038

ABSTRACT

The determinants of the structure, functioning and resilience of pelagic ecosystems across most of the polar regions are not well known. Improved understanding is essential for assessing the value of biodiversity and predicting the effects of change (including in biodiversity) on these ecosystems and the services they maintain. Here we focus on the trophic interactions that underpin ecosystem structure, developing comparative analyses of how polar pelagic food webs vary in relation to the environment. We highlight that there is not a singular, generic Arctic or Antarctic pelagic food web, and, although there are characteristic pathways of energy flow dominated by a small number of species, alternative routes are important for maintaining energy transfer and resilience. These more complex routes cannot, however, provide the same rate of energy flow to highest trophic-level species. Food-web structure may be similar in different regions, but the individual species that dominate mid-trophic levels vary across polar regions. The characteristics (traits) of these species are also different and these differences influence a range of food-web processes. Low functional redundancy at key trophic levels makes these ecosystems particularly sensitive to change. To develop models for projecting responses of polar ecosystems to future environmental change, we propose a conceptual framework that links the life histories of pelagic species and the structure of polar food webs.


Subject(s)
Ecosystem , Food Chain , Antarctic Regions , Arctic Regions , Biodiversity , Climate Change , Oceans and Seas
5.
SADJ ; 66(9): 420-2, 424-5, 2011 Oct.
Article in English | MEDLINE | ID: mdl-23193872

ABSTRACT

AIM: This study investigates the nature, frequency, and outcome of complaints relating to misconduct laid against oral healthcare professionals (OHPs), charged with misconduct in South Africa. METHODS: Records of the Health Professions Council of South Africa (2004-2009) were analysed and classified using the ethical rules as a reference. "Clinically-related complaints" and "fraud" were added as extra categories. The nature and outcome of the complaints and the penalties were quantified, and the detailed nature of the complaints was qualitatively reported. RESULTS: Two percent of the registered dentists and 5.5% of the registered dental therapists were charged with misconduct. Clinically related complaints (59%) and fraud (29%) were most prevalent amongst the accused dentists. Fraud (46%), clinically related complaints (19%), advertising (15%), infection control (8%), and creating expectations that could not be met (8%) were the most common complaints against dental therapists. CONCLUSIONS: Substandard dental treatment and fraud were the main reasons for patient dissatisfaction that led to OHPs being charged with misconduct. Both these undesirable practices may be financially motivated. OHPs should take cognisance of these statistics and should adjust their professional approach accordingly in order to reflect acceptable ethical behaviour.


Subject(s)
Dental Auxiliaries/statistics & numerical data , Dentists/statistics & numerical data , Professional Misconduct/statistics & numerical data , Advertising/statistics & numerical data , Dental Auxiliaries/ethics , Dental Care/statistics & numerical data , Dentist-Patient Relations/ethics , Dentists/ethics , Ethics, Dental , Fraud/statistics & numerical data , Humans , Infection Control, Dental/statistics & numerical data , Malpractice/statistics & numerical data , Retrospective Studies , South Africa
6.
Allergy ; 64(5): 754-61, 2009 May.
Article in English | MEDLINE | ID: mdl-19220213

ABSTRACT

BACKGROUND: False-negative responses to specific inhalation challenge (SIC) with occupational agents may occur. We explored whether assessing changes in sputum cell counts would help improve the identification of bronchial reactivity to occupational agents during SICs. METHODS: The predictive value of the changes in sputum cell counts after a negative FEV(1) response to a first challenge exposure to an occupational agent was determined using the changes in airway calibre observed during repeated challenges as the 'gold standard'. The study included 68 subjects investigated for work-related asthma in a tertiary centre. After a control day, the subjects were challenged with the suspected occupational agent(s) for up to 2 h. All subjects who did not show an asthmatic reaction were re-challenged on the following day. Additional challenges were proposed to those who demonstrated a > or = 2% increase in sputum eosinophils or an increase in nonspecific bronchial hyperresponsiveness to histamine after the second challenge day. RESULTS: Six of the 35 subjects without changes in FEV(1) on the first challenge developed an asthmatic reaction on subsequent challenges. ROC analysis revealed that a >3% increase in sputum eosinophils at the end of the first challenge day was the most accurate parameter for predicting the development of an asthmatic response on subsequent challenges with a sensitivity of 67% and a specificity of 97%. CONCLUSIONS: An increase in sputum eosinophils is an early marker of specific bronchial reactivity to occupational agents, which may help to identify subjects who will develop an asthmatic reaction only after repeated exposure.


Subject(s)
Asthma/diagnosis , Eosinophilia/diagnosis , Eosinophils/immunology , Occupational Diseases/diagnosis , Occupational Exposure , Sputum/immunology , Adult , Allergens/immunology , Asthma/immunology , Biomarkers , Bronchial Provocation Tests , Eosinophilia/immunology , Female , Humans , Leukocyte Count , Male , Middle Aged , Occupational Diseases/immunology , Respiratory Function Tests , Spirometry , Sputum/cytology
8.
Acta Clin Belg ; 51(3): 135-43, 1996.
Article in English | MEDLINE | ID: mdl-8766212

ABSTRACT

The article presents the clinical profile of 72 patients with somatization seen by a psychiatric team at the request of somaticians in a emergency service in St Luc hospital (Brussels-Belgium). These include 37.5% of mood disorders, 11% of psychotic disorders and 20% of serious anxiety disorders. The psychiatric antecedents of these patients are very poor. Only the combined intervention of the somatician and the psychiatrist can improve the compliance and the level of psychiatric care which is very low.


Subject(s)
Emergencies , Psychophysiologic Disorders/psychology , Adult , Aged , Crisis Intervention , Demography , Female , Humans , Male , Middle Aged , Psychophysiologic Disorders/classification , Psychophysiologic Disorders/therapy
9.
J Appl Physiol (1985) ; 66(6): 2857-65, 1989 Jun.
Article in English | MEDLINE | ID: mdl-2745351

ABSTRACT

The relationship between exercise-induced focal muscle fiber degeneration and changes in capillary morphology was investigated in male Wistar rats. Untrained animals ran on a treadmill for 1 h at submaximal intensity and were killed 0, 6, or 24 h after running. Nonexercised rats served as controls. In situ perfused soleus muscles were prepared for electron microscopy. Micrographed cross sections were quantitatively analyzed for parameters indicative of capillary blood flow or transcapillary exchange. Capillary lumina were ovally rather than circularly shaped, and no indications for obstruction of blood flow at the capillary level were found. Endothelial cells and their organelles had a normal appearance in all groups. However, immediately after exercise, capillaries showed a decreased thickness of their endothelium and basal membrane, probably caused by dehydration. Six hours after exercise, muscle fibers were swollen (28% increase in cross-sectional area), resulting in a slightly increased diffusion distance. This fiber swelling was not associated with an increase in muscle water content, a finding for which no explanation could be found. Twenty-four hours after the animals ran, capillaries located near degenerated muscle fibers had an increased cross-sectional luminal area and an increased luminal circumference. This effect decreased gradually with increasing distance from the degenerated fiber area. The present morphometric results do not support the hypothesis that changes in capillary morphology primarily contribute to exercise-induced focal muscle fiber degeneration.


Subject(s)
Muscles/anatomy & histology , Physical Exertion , Animals , Capillaries/anatomy & histology , Capillaries/ultrastructure , Male , Microscopy, Electron , Muscles/blood supply , Muscles/pathology , Muscles/ultrastructure , Rats , Rats, Inbred Strains
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