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And Water (and + water)
Kinds of And Water Terms modified by And Water Selected AbstractsTreatment technologies for mercury in soil, waste, and waterREMEDIATION, Issue 1 2007Martha Otto Mercury occurs naturally in the environment and can be found in elemental (metallic), inorganic, and organic forms. Modern uses for mercury include chemical manufacturing, thermometers, and lighting (mercury vapor and fluorescent lamps). The chemical and allied products industry group is responsible for the largest quantity of mercury used in the United States. Mercury, particularly the organic methylmercury form, is a potent neurotoxin capable of impairing neurological development in fetuses and young children and of damaging the central nervous system of adults. Mercury regulations span multiple federal and state environmental statutes, as well as multiple agency jurisdictions. In August 2007, the U.S. Environmental Protection Agency's (US EPA's) Office of Superfund Remediation and Technology Innovation (OSRTI) published a report titled "Treatment Technologies for Mercury in Soil, Waste, and Water." The report identifies eight treatment technologies and 57 projects, 50 of which provide performance data. This information can help managers at sites with mercury-contaminated media and generators of mercury-contaminated waste and wastewater to identify proven and effective mercury treatment technologies; screen technologies based on application-specific goals, characteristics, and costs; and apply experiences from sites with similar treatment challenges. This article provides a synopsis of the US EPA report, which is available at http://clu-in.org/542R07003. © 2007 Wiley Periodicals, Inc., [source] Resource variability, aggregation and direct density dependence in an open context: the local regulation of an African elephant populationJOURNAL OF ANIMAL ECOLOGY, Issue 1 2008Simon Chamaillé-Jammes Summary 1An emerging perspective in the study of density dependence is the importance of the spatial and temporal heterogeneity of resources. Although this is well understood in temperate ungulates, few studies have been conducted in tropical environments where both food and water are limiting resources. 2We studied the regulation of one of the world's largest elephant populations in Hwange National Park, Zimbabwe. The study period started in 1986 when the population was released from culling. Using census data we investigated changes in elephant abundance with respect to rainfall and density across the entire park and across waterholes. 3The population more than doubled since culling stopped. The population increased continuously during the first 6 years, and then fluctuated widely at about 30 000 individuals. Immigration processes must have been involved in the increase of the population size. 4Population growth rates were negatively related to previous population density by a convex relationship, and negatively related to the ratio of previous population density on annual rainfall by a linear relationship. However, only this latter model (i.e. assuming a fluctuating carrying capacity related to annual rainfall) produced realistic dynamics. Overall, population decreased during dry years when the elephant density was high. 5During dry years there were fewer waterholes retaining water during the dry season and consequently elephant numbers at waterholes increased, while their aggregation level across waterholes decreased. On the long-run elephant numbers increased only at the less crowded waterholes. 6We suggest that the interaction between population size and the available foraging range determined by the number of active waterholes during the dry season controls the park population. 7Our results emphasize the need to understand how key-resource areas cause resource-based aggregation, which ultimately influences the strength of density dependence. More specifically, this study suggests that climate variability strongly affects local elephant population dynamics through changes in surface-water availability. Finally, as dispersal is likely to be an important driver of the dynamics of this population, our results support views that a metapopulation framework should be endorsed for elephant management in open contexts. [source] Tufted ducks Aythya fuligula do not control buoyancy during divingJOURNAL OF AVIAN BIOLOGY, Issue 3 2005Lewis G. Halsey Work against buoyancy during submergence is a large component of the energy costs for shallow diving ducks. For penguins, buoyancy is less of a problem, however they still seem to trade-off levels of oxygen stores against the costs and benefits of buoyant force during descent and ascent. This trade-off is presumably achieved by increasing air sac volume and hence pre-dive buoyancy (Bpre) when diving deeper. Tufted ducks, Aythya fuligula, almost always dive with nearly full oxygen stores so these cannot be increased. However, the high natural buoyancy of tufted ducks guarantees a passive ascent, so they might be expected to decrease Bpre before particularly deep, long dives to reduce the energy costs of diving. Body heat lost to the water can also be a cause of substantial energy expenditure during a dive, both through dissipation to the ambient environment and through the heating of ingested food and water. Thus dive depth (dd), duration and food type can influence how much heat energy is lost during a dive. The present study investigated the relationship between certain physiological and behavioural adjustments by tufted ducks to dd and food type. Changes in Bpre, deep body temperature (Tb) and dive time budgeting of four ducks were measured when diving to two different depths (1.5 and 5.7 m), and for two types of food (mussels and mealworms). The hypothesis was that in tufted ducks, Bpre decreases as dd increases. The ducks did not change Bpre in response to different diving depths, and thus the hypothesis was rejected. Tb was largely unaffected by dives to either depth. However, diving behaviour changed at the greater dd, including an increase in dive duration and vertical descent speed. Behaviour also changed depending on the food type, including an increase in foraging duration and vertical descent speed when mussels were present. Behavioural changes seem to represent the major adjustment made by tufted ducks in response to changes in their diving environment. [source] Prevalence and associated factors of pneumonia in patients with vegetative state in TaiwanJOURNAL OF CLINICAL NURSING, Issue 7 2008Li-Chan Lin PhD Aims., The aim of this study was to investigate the prevalence rate and influencing factors of pneumonia associated with long-term tube feeding in special care units for patients with persistent vegetative states (PVS) in Taiwan. Background., Pneumonia is a significant cause of morbidity, hospitalization and mortality in the nursing home population. Tube feeding has been found as a risk factor for the occurrence of pneumonia. Methods., Two hundred sixty subjects were chosen from three hospital-based special care units for patients with PVS and 10 nursing facilities for persons in PVS in Taiwan. All subjects, who were diagnosed with PVS, received either financial aid for institutional care or were means-tested from The Bureau of Social Welfare of cities and counties in Taiwan. Data were collected through chart review and observations. Results., The prevalence rate of pneumonia in nursing facilities for patients with PVS was 14·2%. The prevalence rate of tube-feeding in nursing facilities for PVS was 91·2%. The mean duration of tube-feeding was 73·21 SD 55·33 months. A total of 90·4% was fed with a nasogastric (NG) tube. Having a lower intake of food and fluids daily and having been institutionalized for a shorter period were three dominant factors associated with the occurrence of pneumonia. Conclusion., Research findings reveal that the incidence of pneumonia is higher in patients who do not receive adequate food and water. Continuing in-service training to improve caregivers' knowledge and skill in providing care to patients in PVS and monitoring their skills in feeding is needed to decrease the occurrence of pneumonia in this population. Relevance to clinical practice., Staff needs to be taught to monitor laboratory data and signs and symptoms of malnutrition and hydration deficit, and also be alert to early indicators of pneumonia in patients with PVS. [source] INDIVIDUAL AND COMBINED CYTOTOXIC EFFECTS OF THE MAJOR FOUR AFLATOXINS IN DIFFERENT IN VITRO STABILIZED SYSTEMSJOURNAL OF FOOD BIOCHEMISTRY, Issue 5 2010CORNELIA BRAICU ABSTRACT The present study aims to investigate the cytotoxic effect of the major aflatoxins (B1, B2, G2 and G2) and also aflatoxin combination, using a simple, rapid and cheap cytotoxicity test like MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay in three in vitro models (human umbilical vein endothelial cells [HUVEC], human lung fibroblasts [HFL] and A2780 cell line) and to extrapolate the data to in vivo situation using a prediction model. A difference in cell sensitivity has been observed for B1 and B1 + B2, in the following order A2789 > HFL > HUVEC, while for B2, G1, G2, Mix (B1 + B2 + G1 + G2) the order was HFL > A2789 > HUVEC when comparing the IC50 (half maximal inhibitory concentration) values. We confirm that in vitro cytotoxicity test MTT assay is able to predict in vivo toxicity, at least for aflatoxins using the prediction model. The values of LD50 (lethal dose 50%) calculated from experiments are different for each cell line. This fact may indicate that some species are more resistant than other and target organs are not necessarily those predicted, because the A2780 ovarian cancer cells seem to be more sensitive to B1 than cells of endothelial or fibroblasts origin. PRACTICAL APPLICATIONS This study is in concordance with the international tendency that refined the current techniques to lessen pain or distress, to reduce the number of animals necessary for a particular test or to replace animals with non-whole-animal models, such as in vitro cell cultures. The practical application of such methodologies may help solve the economic problem related to very expensive in vivo toxicology studies and implement preventive methods based on the calculated data and known mechanism of action of individual or combined toxins easily studied in vitro. The nature of coexistence of many types of mycotoxins in complex environmental samples, such as food and water, has been reported worldwide. How these mycotoxins might affect human health in combination is largely unknown. This study had, as a goal, to test the toxicity of the four aflatoxins and aflatoxin combination on human cells. Due to the lack of aflatoxins mixture data regarding the human cytotoxicity, the aim of this study was to specify, evaluate and predict the combined effects of mycotoxin mixtures. [source] Opioids in the Hypothalamic Paraventricular Nucleus Stimulate Ethanol IntakeALCOHOLISM, Issue 2 2010Jessica R. Barson Background:, Specialized hypothalamic systems that increase food intake might also increase ethanol intake. To test this possibility, morphine and receptor-specific opioid agonists were microinjected in the paraventricular nucleus (PVN) of rats that had learned to drink ethanol. To cross-validate the results, naloxone methiodide (m-naloxone), an opioid antagonist, was microinjected with the expectation that it would have the opposite effect of morphine and the specific opioid agonists. Methods:, Sprague,Dawley rats were trained, without sugar, to drink 4 or 7% ethanol and were then implanted with chronic brain cannulas aimed at the PVN. After recovery, those drinking 7% ethanol, with food and water available, were injected with 2 doses each of morphine or m-naloxone. To test for receptor specificity, 2 doses each of the ,-receptor agonist [d -Ala2,N -Me-Phe4,Gly5 -ol]-Enkephalin (DAMGO), ,-receptor agonist d -Ala-Gly-Phe-Met-NH2 (DALA), or ,-receptor agonist U-50,488H were injected. DAMGO was also tested in rats drinking 4% ethanol without food or water available. As an anatomical control for drug reflux, injections were made 2 mm dorsal to the PVN. Results:, A main result was a significant increase in ethanol intake induced by PVN injection of morphine. The opposite effect was produced by m-naloxone. The effects of morphine and m-naloxone were exclusively on intake of ethanol, even though food and water were freely available. In the analysis with specific receptor agonists, PVN injection of the ,-agonist DALA significantly increased 7% ethanol intake without affecting food or water intake. This is in contrast to the ,-agonist U-50,488H, which decreased ethanol intake, and the ,-agonist DAMGO, which had no effect on ethanol intake in the presence or absence of food and water. In the anatomical control location 2 mm dorsal to the PVN, no drug caused any significant changes in ethanol, food, or water intake, providing evidence that the active site was close to the cannula tip. Conclusions:, The ,-opioid receptor agonist in the PVN increased ethanol intake in strong preference over food and water, while the ,-opioid agonist suppressed ethanol intake. Prior studies show that learning to drink ethanol stimulates PVN expression and production of the peptides enkephalin and dynorphin, which are endogenous agonists for the ,- and ,-receptors, respectively. These results suggest that enkephalin via the ,-opioid system can function locally within a positive feedback circuit to cause ethanol intake to escalate and ultimately contribute to the abuse of ethanol. This is in contrast to dynorphin via the ,-opioid system, which may act to counter this escalation. Naltrexone therapy for alcoholism may act, in part, by blocking the enkephalin-triggered positive feedback cycle. [source] Patterns of Ethanol Intake in Preadolescent, Adolescent, and Adult Wistar Rats Under Acquisition, Maintenance, and Relapse-Like ConditionsALCOHOLISM, Issue 4 2009David García-Burgos Background:, Animal behavioral models of voluntary ethanol consumption represent a valuable tool to investigate the relationship between age and propensity to consume alcohol using an experimental methodology. Although adolescence has been considered as a critical age, few are the studies that consider the preadolescence age. This study examines the ethanol consumption/preference and the propensity to show an alcohol deprivation effect (ADE) after a short voluntary ethanol exposure from a developmental perspective. Methods:, Three groups of heterogeneous Wistar rats of both sexes with ad libitum food and water were exposed for 10 days to 3 ethanol solutions at 3 different ontogenetic periods: preadolescence (PN19), adolescence (PN28), and adulthood (PN90). Ethanol intake (including circadian rhythm), ethanol preference, water and food consumption, and ADE were measured. Results:, During the exposure, the 3 groups differed in their ethanol intake; the greatest amount of alcohol (g/kg) was consumed by the preadolescent rats while the adolescents showed a progressive decrease in alcohol consumption as they approached the lowest adult levels by the end of the assessed period. The pattern of ethanol consumption was not fully explained in terms of hyperphagia and/or hyperdipsia at early ages, and showed a wholly circadian rhythm in adolescent rats. After an abstinence period of 7 days, adult rats showed an ADE measured both as an increment in ethanol consumption and preference, whereas adolescent rats only showed an increment in ethanol preference. Preadolescent rats decreased their consumption and their preference remained unchanged. Conclusions:, In summary, using a short period of ethanol exposure and a brief deprivation period the results revealed a direct relationship between chronological age and propensity to consume alcohol, being the adolescence a transition period from the infant to the adult pattern of alcohol consumption. Preadolescent animals showed the highest ethanol consumption level. The ADE was only found in adult animals for both alcohol consumption and preference, whereas adolescents showed an ADE only for preference. No effect of sex was detected in any phase of the experiment. [source] The ,1 -Adrenergic Receptor Antagonist, Prazosin, Reduces Alcohol Drinking in Alcohol-Preferring (P) RatsALCOHOLISM, Issue 2 2009Dennis D. Rasmussen Background:, Preliminary evidence suggest that noradrenergic signaling may play a role in mediating alcohol drinking behavior in both humans and rats. Accordingly, we tested the hypothesis that blockade of ,1 -adrenergic receptors will suppress alcohol drinking in rats selectively bred for alcohol preference (P line). Methods:, Adult male P rats were given 24-hour access to food and water and scheduled access to a 15% (v/v) alcohol solution for 2 hours daily. Rats were injected IP with the ,1 -adrenergic receptor antagonist, prazosin (0, 0.5, 1.0, 1.5, or 2.0 mg/kg body weight), once a day at 15 minutes prior to onset of the daily 2-hour 2-bottle choice, alcohol versus water, access period for 2 consecutive days and then 3 weeks later for 5 consecutive days. Results:, Prazosin significantly reduced (p < 0.01) alcohol intake during the initial 2 daily administrations, and this reduction of alcohol intake was maintained for 5 consecutive days by daily prazosin treatment in the subsequent more prolonged trial (p < 0.05). The prazosin-induced reduction of alcohol intake was not dependent upon drug-induced motor impairment since increases in water drinking (p < 0.05) were exhibited during the 2-hour access periods during both 2- and 5-day prazosin treatment. Conclusions:, The results indicate that the noradrenergic system plays a role in mediating alcohol drinking in rats of the P line and suggest that prazosin,a safe, well-characterized, and well-tolerated drug,may be an effective pharmacotherapeutic agent for the treatment of alcohol use disorders. [source] Proteomic Analysis Demonstrates Adolescent Vulnerability to Lasting Hippocampal Changes Following Chronic Alcohol ConsumptionALCOHOLISM, Issue 1 2009Garth A. Hargreaves Background:, Excessive teenage alcohol consumption is of great concern because alcohol may adversely alter the developmental trajectory of the brain. The aim of the present study was to assess whether chronic intermittent alcohol intake during the adolescent period alters hippocampal protein expression to a greater extent than during adulthood. Methods:, Adolescent [postnatal day (PND) 27] and adult (PND 55) male Wistar rats were given 8 hours daily access to beer (4.44% ethanol v/v) in addition to ad libitum food and water for 4 weeks. From a large subject pool, subgroups of adolescent and adult rats were selected that displayed equivalent alcohol intake (average of 6.1 g/kg/day ethanol). The 4 weeks of alcohol access were followed by a 2-week alcohol-free washout period after which the hippocampus was analyzed using 2-DE proteomics. Results:, Beer consumption by the adult group resulted in modest hippocampal changes relative to alcohol naïve adult controls. The only changes observed were an up-regulation of citrate synthase (a precursor to the Krebs cycle) and fatty acid binding protein (which facilitates fatty acid metabolism). In contrast, adolescent rats consuming alcohol showed more widespread hippocampal changes relative to adolescent controls. These included an increase in cytoskeletal protein T-complex protein 1 subunit epsilon (TCP-1) and a decrease in the expression of 10 other proteins, including glyceraldehyde-3-phosphate dehydrogenase (GAPDH), triose phosphate isomerise, alpha-enolase, and phosphoglycerate kinase 1 (all involved in glycolysis); glutamate dehydrogenase 1 (an important regulator of glutamate); methylmalonate-semialdehyde dehydrogenase (involved in aldehyde detoxification); ubiquitin carboxyl-terminal hydrolase isozyme L1 (a regulator of protein degradation); and synapsin 2 (involved in synaptogenesis and neurotransmitter release). Conclusions:, These results suggest the adolescent hippocampus is more vulnerable to lasting proteomic changes following repeated alcohol exposure. The proteins most affected include those related to glycolysis, glutamate metabolism, neurodegeneration, synaptic function, and cytoskeletal structure. [source] Beyond Bland: a critique of the BMA guidance on withholding and withdrawing medical treatmentLEGAL STUDIES, Issue 1 2000John Keownz MA (Cantab) D Phil (Oxon) In Bland1 the House of Lords held it lawful to withdraw tube-feeding from a patient in a ,persistent vegetative state' (pvs), even with intent to kill him. The British Medical Association (BMA) recently published guidance on the withholding and withdrawal of ,medical treatment', so defined as to include food and water delivered by tube. The guidance endorses the withholding/withdrawal of tube-delivered food and water not only from patients in pvs but also from other non-terminally ill patients, such as those with severe dementia or serious stroke. The underlying justification appears (as in Bland) to be that such lives lack worth. This article offers three major criticisms of the guidance. First, its argument that tube-feeding is medical treatment rather than basic care is weak. Secondly, its reasons for not treating or tube-feeding undermine the BMA's longstanding opposition to active euthanasia and active assisted suicide. Thirdly, it relies heavily on legal precedent at the expense of ethical reasoning. [source] Management of flood victims: Chainat Province, central ThailandNURSING & HEALTH SCIENCES, Issue 1 2010Anchaleeporn Wisitwong rn Abstract This article focuses on the processes of flood management and the experiences of flood victims in Chainat Province, central Thailand, so as to develop knowledge about the future handling of such disasters. A phenomenological qualitative approach was used to describe the processes of providing assistance to flood victims. In-depth interviews and observation were used to collect the data. Criterion sampling was used to select 23 participants. Content analysis of the data revealed that some flood victims could predict flooding based on prior experiences, so they prepared themselves. The data revealed six themes that demonstrated that those who could not predict how floods would impact on them were unprepared and suffered losses and disruption to their daily life. Damaged routes meant people could not go to work, resulting in the loss of income. There was a lack of sanitary appliances and clean drinking water, people were sick, and experienced stress. At the community level, people helped one another, making sandbags and building walls as a defense against water. They formed support groups to enable the processing of stressful experiences. However, later, the water became stagnant and contaminated, creating an offensive smell. The government provided assistance to cut off electricity services, food and water, toilets and health services, and water drainage. In the recovery phase, the victims needed money for investment, employment opportunities, books for children, extra time to pay off loans, reconnection of electricity, surveys of damage, and pensions to deal with damage and recovery. [source] Adult female crickets, Gryllus texensis, maintain reproductive output after repeated immune challengesPHYSIOLOGICAL ENTOMOLOGY, Issue 2 2007KELLY L. SHOEMAKER Abstract Both immunity and reproduction are thought to be energetically costly and therefore likely to make trade-offs with one another. To assess whether increasing immune system activity results in a decline in egg production, the immune system in the cricket Gryllus texensis is activated over a period of 12 days with regular injections of lipopolysaccharide (LPS) derived from Serratia marcescens, and the number of eggs laid during this time counted. Egg quality is also assessed by measuring total protein of eggs laid, fertilization and hatching success, and the weight of individual eggs laid after the series of injections. Indirect evidence suggests that LPS induces an immune response in G. texensis. However, the number of eggs produced is not affected. There is also no effect of repeated LPS injections on female weight, egg protein content, or fertilization and hatching success. Taken together, these results suggest that with food and water provided ad libitum, females can protect many aspects of fitness in the face of increased immune system activity. However, there is some evidence to suggest that large (100 ,g) doses of LPS lead to reduced female longevity, and also in egg weight that could affect offspring success. Although the possibility exists that the decline in lifespan and egg weight after high-dose injections reflects a trade-off between reproduction and immune investment, another possibility is that these doses yield nonspecific effects, or that the high-dose induces an overwhelming immune response that leads to self-damage. [source] Effects of maternal age on reproductive traits and fitness components of the offspring in the bruchid beetle, Callosobruchus chinensis (Coleoptera: Bruchidae)PHYSIOLOGICAL ENTOMOLOGY, Issue 4 2002Shin-Ichi Yanagi Abstract. In many insect species, the size and number of eggs decrease with maternal age. Thus, both the size and number of eggs must be considered to know the exact cost of reproduction with maternal age. The resource depletion hypothesis was examined in the bruchid beetle Callosobruchus chinensis. The hypothesis explains why the egg size decreases with maternal age based on the decline of the female's reproductive capacity. A decrease was found in reproductive effort (= egg size × the number of eggs) and the fitness component of offspring with maternal age. The effects of the female's nutritional status on the relationship between maternal age and the reproductive effort of females with and without food and water were also examined. The results indicate that the decrease in size and number of eggs with maternal age can be explained by the resource depletion hypothesis in C. chinensis. [source] Rhetoric, Realism and Benefit-SharingTHE JOURNAL OF WORLD INTELLECTUAL PROPERTY, Issue 6 2004Use of Traditional Knowledge of Hoodia Species in the Development of an Appetite Suppressant "This is the real ghaap of the natives, who use it as a substitute for food and water. The sweet sap reminds one of licorice and when on one occasion thirst compelled me to follow the example of my Hottentot guide, it saved further suffering and removed the pangs of hunger so efficiently that I could not eat anything for a day after having reached the camp." Marloth (1855,1931) [source] Photic and non-photic entrainment on daily rhythm of locomotor activity in goatsANIMAL SCIENCE JOURNAL, Issue 1 2010Claudia GIANNETTO ABSTRACT We studied the photic (L/D cycle) and non-photic (restricted feeding) entrainment on the patterns of daily rhythm of total locomotor activity in goats. Six female Maltese goats were subjected to three different artificial L/D cycles: 12/12 L/D, 12/12 D/L and constant light. During the 12/12 L/D and 12/12 D/L, food and water were available ad libitum. During constant light, animals were subjected to a restricted feeding treatment. Total activity was recorded by means of an actigraphy-based data logger (Actiwatch-Mini®). Our results showed that goats exhibited clear daily rhythms of activity in 12/12 L/D cycle, 12/12 D/L cycle and constant light, although they showed FAA prior the feeding time during the restricted feeding treatment. Goats were diurnal, with activity consistently beginning promptly following the onset of light. Even when the L/D cycle was delayed by 12 h on some days, to the daily rhythm was re-established. During the constant light period, the onset of activity was linked to the time of food administration. Our study evidences two factors for the rhythm of total locomotor activity in goats: light stimuli (photic) and food access (non photic), strongly coupled to permit organisms the adaptive temporal coordination of behaviour with stable and unstable environmental periodicities. [source] Physiological responses of young cross-bred calves immediately after long-haul road transportation and after one week of habituationANIMAL SCIENCE JOURNAL, Issue 6 2009Katsuji UETAKE ABATRACT We investigated 10 suckling cross-bred calves (Japanese Black (Wagyu) × Holstein) and collected data on the physiological stress responses of the young calves to long-haul road transportation. All calves were male and 21,47 days of age. The calves were obtained at a livestock market and were transported from the market to the university in a commercial livestock vehicle. The total haul distance and time were 306.9 km and 7 h, respectively. The calves were deprived of food and water during transportation. Blood samples, electrocardiograms, and rectal temperatures were collected immediately after transportation and after one week of habituation at the university. Serum pH was significantly lower (P < 0.01), while serum triiodothyronine, aspartate aminotransferase, non-esterified fatty acids (all P < 0.05), and heart rate (P < 0.01) were significantly higher immediately after transportation. The concentrations of blood lactic acid (P = 0.08) and serum alanine aminotransferase (P = 0.06) tended to be higher after transportation. These physiological responses suggest that the stress caused by long-haul transportation causes significant effects on liver function in young calves. [source] Global Mapping of Ecosystem Disservices: The Unspoken Reality that Nature Sometimes Kills usBIOTROPICA, Issue 5 2010Robert R. Dunn ABSTRACT Increasingly, we view nature through a utilitarian lens that leads us to attempt to measure and manage the services that species, habitats and ecosystems provide. Surprisingly, we have tended to consider only the positive values of ecosystems, their ecosystem services. In addition to providing our food and water, Nature also kills us, primarily through disease. If we are to effectively manage the terrestrial Earth, we need to also manage species, habitats and ecosystems so as to minimize such ,ecosystem disservices'. I consider what we know about the spatial pattern of one disservice, pathogen prevalence and how changes in habitat influence it. I consider the effects of habitat changes on pathogen prevalence and, consequently, ecosystem disservices. In the end, we need to weigh both the costs and the benefits of particular ecosystems, habitats and species , to consider the bad with the good. Doing so requires that we learn much more about the biota than we currently know. [source] ,Finding a Life' Among Undocumented Congolese Refugee Children in TanzaniaCHILDREN & SOCIETY, Issue 4 2010Gillian Mann The majority of undocumented Congolese refugee children living in Dar es Salaam, Tanzania, experience extreme poverty and social exclusion, harassment and discrimination. Their fear of deportation, forcible removal to refugee camps and imprisonment is coupled with a strong feeling that they are unwelcome in Tanzania. These realities require that most children devote a huge amount of their energy to survival, both literally, in terms of physical needs such as food and water, and figuratively, in terms of maintaining their sense of self-worth, dignity and purpose. This article is based on extensive fieldwork with more than 100 young people aged 7,18 years. I explore the ways children cope with the challenges posed by the conditions of everyday life and the strategies they employ in their quest to ,find a life', or make a future for themselves. I argue that by imagining a future, they are fighting against not only what war has done to them and their families but also against the very fact of being a refugee. [source] Time Of Day And Access To Food Alter Water Intake In Rats After Water DeprivationCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 9 2001Kooi K Ang SUMMARY 1. Drinking behaviour after water deprivation is one of the standard tests used to study thirst in humans and animals. Diurnal cycle and food availability are known to influence water intake, but have not been considered in previous studies of thirst after water deprivation. In the present study, we examined the effects of diurnal variation and food availability on water intake after 24 h water deprivation in rats. 2. All rats cycled through four treatments in varying order. These treatments were: (i) 24 h water deprivation with free access to food from 1900 h one day to 1900 h the next day, followed by free access to both food and water (Night-with-Food); (ii) 24 h water deprivation with free access to food from from 1900 h one day to 1900 h the next day, followed by free access to water but not food (Night-without-Food); (iii) 24 h water deprivation with free access to food from 0700 h one day to 0700 h the next day, followed by free access to both food and water (Day-with-Food); or (iv) 24 h water deprivation with free access to food from 0700 h one day to 0700 h the next day, followed by free access to water but not food (Day- without-Food). The amount of water consumed during the first 6 h, post-24 h water deprivation, was examined under each condition. 3. There was a significant diurnal effect (P < 0.001) and a significant food availability effect (P = 0.007) on the water consumed in the 6 h period after water deprivation. Most water was consumed by the Night-with-Food group and the least amount of water was consumed by the Day-without-Food group. These effects persisted after correction for water intake during 6 h periods from 0700 and 1900 h with and without food but without previous water deprivation. The diurnal and food availability effects on water consumption were independent (P = 0.5). 4. The coefficient of variability for each group suggests that the most sensitive measurements of water intake are obtained during the day in the absence of food. 5. We conclude that both the time of day and access to food independently alter water intake in rats subjected to a previous 24 h water deprivation. Our study also supports the validity of performing water intake measurements in thirst studies in rats during the day. [source] | ||||||||||||||||