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Long Term Effects (long + term_effects)
Selected AbstractsLong term effects of cormorant predation on fish communities and fishery in a freshwater lakeECOGRAPHY, Issue 2 2001Henri Engström Cormorant impact upon natural fish populations has long been debated but little studied because of the requirements of sound data that are often hard to fill. In this study I have monitored fish community composition/abundance before and after a cormorant colony was established in a high productive lake, Ymsen, of south-central Sweden. Data on fish abundance before cormorant establishment enabled me to control for changes in fish densities prior to cormorant colonisation. To control for possible changes in fish populations caused by factors other than cormorant predation (i.e. large-scale regional changes due to climate) data were compared with a control lake, Garnsviken, with no cormorants. Since Lake Ymsen also harbour an important commercial fishery, cormorant impact upon fishery yields was evaluated. The most important fish species in the diet of the cormorants were ruffe (75% by number), roach (11%) and perch (10%). Except for perch, commercially important fish made up a very small fraction of the cormorant diet. Eel, the most important fish for the fishery, was absent in the cormorant diet, pikeperch constituted 0.2% and pike 1.5%. Estimated fish outtake by the cormorants was 12.8 kg ha,1 yr,1 compared to 8.6 kg ha,1 yr,1 for the fishery. Despite considerable fish withdrawal by the cormorants, fish populations did not seem to change in numbers or biomass. The present study indicates that cormorant impact upon fish populations in Lake Ymsen was small and probably in no case has led to declines of neither commercial nor of non-commercial fish species. Still, the number of breeding cormorants in Lake Ymsen, in relation to foraging area, is among the highest known for Swedish lakes. [source] Local alendronate increases fixation of implants inserted with bone compaction: 12-week canine studyJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 4 2007Thomas Jakobsen Abstract Bone compaction has been shown to increase initial implant fixation. Furthermore, bone compaction creates a peri-implant zone of autograft that exerts osteoconductive properties. We have previously shown that locally applied bisphosphonate (alendronate) at 4-week observation can preserve the autograft generated by bone compaction. We now investigate whether the increased amount of autograft, seen at 4 weeks, can increase implant osseointegration and biomechanical fixation. Porous-coated titanium implants were bilaterally inserted with bone compaction into the proximal part of tibia of 10 dogs. On the right side, local bisphosphonate was injected into the bone cavity prior to bone compaction immediately prior to implant insertion. On the left side, saline was used as control. Observation period was 12 weeks. Locally applied bisphosphonate significantly increased biomechanical implant fixation (approximately twofold), bone-to-implant contact (1.2-fold), and peri-implant bone volume fraction (2.3-fold). This study indicates that local alendronate treatment can increase early implant osseointegration and biomechanical fixation of implants inserted by use of bone compaction. Long term effects remain unknown. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:432,441, 2007 [source] Long term effects of exercise training on physical activity level and quality of life in elderly coronary patients , A three- to six-year follow-upPHYSIOTHERAPY RESEARCH INTERNATIONAL, Issue 1 2003Camilla Hage Abstract Background and Purpose Physical activity and exercise as part of cardiac rehabilitation after an acute coronary event improves exercise capacity and quality of life in most patients. The aim of the present study was to evaluate physical activity level, health-related quality of life (HRQL) and perceived health three to six years after an acute myocardial infarction or an episode of unstable angina pectoris in elderly patients and compare this to earlier follow-up examination data. Method Study design: three to six years (mean 4.4 years) after randomization a questionnaire about physical activity level, HRQL and perceived health was mailed to all subjects alive (n = 93) (response rate 96 Results Since the one-year follow-up examination eight subjects had died: five in the intervention group and three in the control group. At randomization, the level of physical activity level was similar in the two groups. Those in the intervention group improved their level of physical activity significantly over time (p = 0.05) in contrast to the control group. Measurements of HRQL showed no statistical difference between the groups by use of the EuroQol instrument. However, a small advantage for the intervention group measured over time was noted. Conclusion It is important to include elderly patients in cardiac rehabilitation programmes after an acute coronary event, since even a short period of supervised exercise training has the potential to positively influence physical activity level for as long as three to six years. Copyright © 2003 Whurr Publishers Ltd. [source] The Evolution of Research in Family and Consumer Sciences: Food, Nutrition, and HealthFAMILY & CONSUMER SCIENCES RESEARCH JOURNAL, Issue 2 2001Eleanor D. SchlenkerArticle first published online: 2 JUL 200 Changing perspectives in food, nutrition, and health are bringing new research opportunities. Knowledge that nutrients and other food substances prevent chronic disease expanded the study of dietary requirements beyond merely obviating deficiency. Government policy makers mandate food guidance programs to enable consumers to choose foods that are culturally appropriate yet support health. Intervention strategies leading to suitable food behavior are needed to address the rising health costs associated with aging and chronic diseases. Functional foods carrying added health benefits have gripped the attention of food producers and consumers, yet much is to be learned regarding long term effects. FCS professionals are uniquely qualified to study not only the theoretical bases of these issues but also their impact on the physical and psychosocial well-being of families. Research methods and applications must be incorporated at all academic levels to prepare FCS professionals to meet the research opportunities and challenges ahead. [source] Toxicology and health risks of hydroquinone in skin lightening formulationsJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 7 2006TJ Kooyers ABSTRACT Background, Hydroquinone has been used for decades as a skin lightening agent. As a result of concerns about mid-term effects like leukomelanoderma en confetti and exogenous ochronosis, its use in cosmetics has been banned since January 2001. Objective, Until recently no attention was paid to potential long-term side-effects, despite the fact that there are indications that these may exist. It was decided that a clearer picture of these potential long term effects was needed. Methods, A literature search was conducted with an emphasis on the biochemistry and toxicology of hydroquinone, benzene and related molecules. Results, It appeared that since 1996 an enormous amount of articles have been published on the carcinogenicity of hydroquinone, benzene and related molecules. The literature search on hydroquinone as a skin lightening agent suggests that possible long-term effects like carcinogenesis may be expected. Conclusion, The risks of long-term effects (cancer) of topically applied hydroquinone may no longer be ignored. Based on recent evidence of the potential risks, which are higher than has been assumed up until now, we plead that the use of hydroquinone as a skin lightening agent will be stopped completely. [source] The Effect of Adolescent Neighborhood Poverty on Adult EmploymentJOURNAL OF URBAN AFFAIRS, Issue 4 2004Steven R. Holloway Urban poverty grew more spatially concentrated during the 1970s and 1980s as industrial economies dramatically restructured. Some policies attempted to address the problems of impoverished neighborhoods by stimulating in-situ economic development, while others sought to geographically disperse the poor. Poverty grew less concentrated during the 1990s because of robust national economic growth and dispersal-oriented federal policies. Before celebrating, however, the long term effects of growing up in poor neighborhoods need to be considered. We used National Longitudinal Survey of Youth (NLSY) data, geocoded to census tracts, to examine the effects of neighborhood poverty rates encountered during adolescence on adult employment. Living in poor neighborhoods during adolescence carries a long-term labor market disadvantage, caused at least in part by the limited ability to accumulate early work experience. Males appear to be more sensitive to these neighborhood effects than females. [source] Pulpal effects of enamel ablation with a microsecond pulsed ,,=,9.3-µm CO2 laserLASERS IN SURGERY AND MEDICINE, Issue 4 2009Michal Staninec DDS Abstract Background and Objectives In vitro studies have shown that CO2 lasers operating at the highly absorbed 9.3 and 9.6-µm wavelengths with a pulse duration in the range of 10,20-microsecond are well suited for the efficient ablation of enamel and dentin with minimal peripheral thermal damage. Even though these CO2 lasers are highly promising, they have yet to receive FDA approval. Clinical studies are necessary to determine if excessive heat deposition in the tooth may have any detrimental pulpal effects, particularly at higher ablative fluencies. The purpose of this study was to evaluate the pulpal safety of laser irradiation of tooth occlusal surfaces under the conditions required for small conservative preparations confined to enamel. Study Design/Materials and Methods Test subjects requiring removal of third molar teeth were recruited and teeth scheduled for extraction were irradiated using a pulsed CO2 laser at a wavelength of 9.3 µm operating at 25 or 50 Hz using a incident fluence of 20 J/cm2 for a total of 3,000 laser pulses (36 J) for both rates with water cooling. Two control groups were used, one with no treatment and one with a small cut made with a conventional high-speed hand-piece. No anesthetic was used for any of the procedures and tooth vitality was evaluated prior to treatment by heat, cold and electrical testing. Short term effects were observed on teeth extracted within 72 hours after treatment and long term effects were observed on teeth extracted 90 days after treatment. The pulps of the teeth were fixed with formalin immediately after extraction and subjected to histological examination. Additionally, micro-thermocouple measurements were used to estimate the potential temperature rise in the pulp chamber of extracted teeth employing the same irradiation conditions used in vivo. Results Pulpal thermocouple measurements showed the internal temperature rise in the tooth was within safe limits, 3.3±1.4°C without water cooling versus 1.7±1.6°C with water-cooling, n,=,25, P<0.05. None of the control or treatment groups showed any deleterious effects on pulpal tissues and none of the 29 test-subjects felt pain or discomfort after the procedure. Only two test-subjects felt discomfort from "cold sensitivity" during the procedure caused by the water-spray. Conclusion It appears that this CO2 laser can ablate enamel safely without harming the pulp under the rate of energy deposition employed in this study. Lasers Surg. Med. 41:256,263, 2009. © 2009 Wiley-Liss, Inc. [source] Influence of chronic alcohol abuse and ensuing forced abstinence on static subjective accommodation function in humansOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 3 2001Hugh Campbell Summary Purpose. Acute alcohol ingestion can change accommodation, but the long term effects of sustained alcohol consumption on accommodative function have not been studied in detail. This study was thus undertaken on individuals with a history of alcohol abuse. Methods. Thirty-seven male individuals aged 25,56 years (average 40 years) from an alcohol rehabilitation centre in Inverness, Scotland, were assessed on admission and after a week of forced abstinence. The results were compared to a paired age-matched set of control male subjects. The static amplitude of accommodation was measured by an RAF rule, and the pupil size measured with a pupil gauge. Results. On admission, the group mean measured amplitude of accommodation was 4.7±2.2 D (mean±SD). These values for the alcoholics were lower than age-matched controls (of5.9±2.9 D). The slope of the age-dependent decline in RAF rule accommodation measures was significantly smaller for the alcoholics compared to controls (at 0.215±0.027 D/year versus0.332±0.015 D/year, respectively; p <0.001), with the younger alcoholics showing a greater impairment. Following abstinence, there was no measurable change in accommodation measured, indicating the lower amplitude in the alcoholics was not attributable to circulatory alcohol levels. The resting pupil diameter in the alcoholics was4.37±0.63 mm compared to the controls of3.97±0.75 mm, with a higher incidence of small pupils (,3 mm) in the controls. Conclusions. The results indicate that chronic alcohol use can adversely affect subjective static accommodation, especially in younger alcoholics, as well as cause slight mydriasis. [source] Concepts of Death Among Professional Alpine Climbers: Continuing Risk Behaviors in the Face of DeathANTHROPOLOGY OF CONSCIOUSNESS, Issue 1-2 2000Paul E. James II Alpine climbing in the US has increased in popularity since the 1970s and despite the high objective risk involved it has continued to find new devotees. For professionals involved in this sport, the risks are encountered through near-death experiences and the real deaths of close friends. This essay uses interviews with climbers in the state of Washington, discussing their experiences with death, and uses written accounts. First, I discuss the many risks involved in climbing and how these risks are perceived and accepted by climbers. Next, 1 look at the immediate reaction to alpine deaths, and finally, to the long term effects on the lives and climbing practices of this group. Despite repeated confrontations with death, all informants continue exposing themselves to these risks. Every year more and more acquaintances die while the ideas and values that these climbers hold allow them to resist the fear of their own death and continue to climb. Keywords: death, risk-taking, sports. [source] Occupational exposures to high frequency electromagnetic fields in the intermediate range (,>300 Hz,10 MHz)BIOELECTROMAGNETICS, Issue 8 2002Birgitta Floderus Abstract The aim of this study was to identify work situations with electromagnetic fields of 300 Hz,10 MHz and to characterize the occupational exposure. Work place investigations included descriptions of the work environment and physical measurements. We estimated electric (E) and magnetic (H) fields by spot measurements in air, by logged exposure data, and when possible, we recorded induced currents in limbs. The instruments used were Wandel and Golterman EFA-3, NARDA 8718, Holaday HI-3702. The exposure sources comprised five induction furnaces, seven induction heaters, one surface treatment equipment, four units of electronic article surveillance (EAS), and medical devices for surgery and muscle stimulation. The induction furnaces operated at 480 Hz,7 kHz, and the maximum values of logged data varied between 512,2093 V/m (E field) and 10.5,87.3 A/m (H field). The induction heaters (3.8 kHz,1.25 MHz) also showed high maximum exposure values of both E and H fields. Three EAS units, an electromagnetic plate at a library, a luggage control unit, and an antitheft gate, showed E fields reaching 658,1069 V/m. The H fields were comparatively lower, except for the antitheft gate (5 and 7.5 kHz) showing a maximum value of 27.2 A/m (recorded during repair). Induced currents of 5,13 mA were measured for the medical devices. The study improves the basis for an exposure assessment for epidemiological studies of long term effects of exposures to high frequency electromagnetic fields. Bioelectromagnetics 23:568,577, 2002. © 2002 Wiley-Liss, Inc. [source] | ||||||||||||||||