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31.
Objective
In Ethiopia, coverage of key health services is low, and community based services have been implemented to improve access to key services. This study aims to describe and assess the level and the distribution of health outcomes and coverage for key services in Ethiopia, and their association with socioeconomic and geographic determinants.Methods
Data were obtained from the 2000, 2005 and 2011 Ethiopian Demographic and Health Surveys. As indicators of access to health care, the following variables were included: Under-five and neonatal deaths, skilled birth attendance, coverage of vaccinations, oral rehydration therapy for diarrhoea, and antibiotics for suspected pneumonia. For each of the indicators in 2011, inequality was described by estimating their concentration index and a geographic Gini index. For further assessment of the inequalities, the concentration indices were decomposed. An index of health achievement, integrating mean coverage and the distribution of coverage, was estimated. Changes from 2000 to 2011 in coverage, inequality and health achievement were assessed.Results
Significant pro-rich inequalities were found for all indicators except treatment for suspected pneumonia in 2011. The geographic Gini index showed significant regional inequality for most indicators. The decomposition of the 2011 concentration indices revealed that the factor contributing the most to the observed inequalities was different levels of wealth. The mean of all indicators improved from 2000 to 2011, and the health achievement index improved for most indicators. The socioeconomic inequalities seem to increase from 2000 to 2011 for under-five and neonatal deaths, whereas they are stable or decreasing for the other indicators.Conclusion
There is an unequal socioeconomic and geographic distribution of health and access to key services in Ethiopia. Although the health achievement indices improved for most indicators from 2000 to 2011, socioeconomic determinants need to be addressed in order to achieve better and more fairly distributed health. 相似文献32.
Contrasting effects of summer and winter warming on body mass explain population dynamics in a food‐limited Arctic herbivore 下载免费PDF全文
Steve D. Albon R. Justin. Irvine Odd Halvorsen Rolf Langvatn Leif E. Loe Erik Ropstad Vebjørn Veiberg René van der Wal Eirin M. Bjørkvoll Elizabeth I. Duff Brage B. Hansen Aline M. Lee Torkild Tveraa Audun Stien 《Global Change Biology》2017,23(4):1374-1389
The cumulative effects of climate warming on herbivore vital rates and population dynamics are hard to predict, given that the expected effects differ between seasons. In the Arctic, warmer summers enhance plant growth which should lead to heavier and more fertile individuals in the autumn. Conversely, warm spells in winter with rainfall (rain‐on‐snow) can cause ‘icing’, restricting access to forage, resulting in starvation, lower survival and fecundity. As body condition is a ‘barometer’ of energy demands relative to energy intake, we explored the causes and consequences of variation in body mass of wild female Svalbard reindeer (Rangifer tarandus platyrhynchus) from 1994 to 2015, a period of marked climate warming. Late winter (April) body mass explained 88% of the between‐year variation in population growth rate, because it strongly influenced reproductive loss, and hence subsequent fecundity (92%), as well as survival (94%) and recruitment (93%). Autumn (October) body mass affected ovulation rates but did not affect fecundity. April body mass showed no long‐term trend (coefficient of variation, CV = 8.8%) and was higher following warm autumn (October) weather, reflecting delays in winter onset, but most strongly, and negatively, related to ‘rain‐on‐snow’ events. October body mass (CV = 2.5%) increased over the study due to higher plant productivity in the increasingly warm summers. Density‐dependent mass change suggested competition for resources in both winter and summer but was less pronounced in recent years, despite an increasing population size. While continued climate warming is expected to increase the carrying capacity of the high Arctic tundra, it is also likely to cause more frequent icing events. Our analyses suggest that these contrasting effects may cause larger seasonal fluctuations in body mass and vital rates. Overall our findings provide an important ‘missing’ mechanistic link in the current understanding of the population biology of a keystone species in a rapidly warming Arctic. 相似文献
33.
Veiberg V Mysterud A Bjørkvoll E Langvatn R Loe LE Irvine RJ Bonenfant C Couweleers F Stenseth NC 《The Journal of animal ecology》2007,76(6):1139-1148
Ruminants depend on efficient physical degradation of forage through chewing to increase the surface area of the food particles presented to the microflora. Fossil evidence suggests that increased molar height is an adaptation for wear tolerance in dry ecosystems with sparse vegetation, but no study has shown selection pressure for hypsodonty in contemporary ruminants. We explored the relationships between particle size in rumen, tooth wear (scanned molar occlusal topography), age and body mass of female Svalbard reindeer living in an arctic desert at 78 degrees latitude on Svalbard. We predicted that (H1) if the rumen particle size is determined mainly by constraints due to tooth wear, and if tooth wear is mainly a function of age, average particle size in rumen should increase with age. From allometric relations it is known that larger individuals can survive on a lower-quality diet, we therefore predicted (H2) larger particle sizes with increases in (ln) body mass, irrespective of age and wear. Lastly, if there is a trade-off between growth and tooth wear in dry ecosystems (a selection pressure for hypsodonty), we predicted (H3) that teeth of heavier animals should be more worn than those of lighter animals of the same age. The proportion of small particles (<1.0 mm) decreased rapidly with increasing age (consistent with H1). Heavier females within an age class had more worn teeth (consistent with H3) than lighter ones. A close-to-isometric relationship between particle size and body mass suggested that heavier animals partly compensated for reduced tooth efficiency by chewing more. We provide the first evidence of a trade-off between fast early growth and wear (a somatic cost) of a senescence-related trait--the structure and height of the molar--in a wild ruminant inhabiting an arctic desert where selection pressure for increased tooth height is expected. This suggests that foraging conditions are more extreme than the environment in which the species originally evolved. 相似文献
34.
35.
David G.I. Kingston Mannava M. Rao Terence D. Spittler Roger C. Pettersen David L. Cullen 《Phytochemistry》1975,14(9):2033-2037
The common western shrub Flourensia cernua has yielded the eremophilane sesquiterpene flourensic acid and a new aromadendrane sesquiterpene flourensadiol. The toxic component(s) of the plant were found in a petrol-soluble fraction. 相似文献
36.
Berg M Parbel A Pettersen H Fenyö D Björkesten L 《Journal of experimental botany》2006,57(7):1509-1514
Traditional analysis of liquid chromatography-mass spectrometry (LC-MS) data, typically performed by reviewing chromatograms and the corresponding mass spectra, is both time-consuming and difficult. Detailed data analysis is therefore often omitted in proteomics applications. When analysing multiple proteomics samples, it is usually only the final list of identified proteins that is reviewed. This may lead to unnecessarily complex or even contradictory results because the content of the list of identified proteins depends heavily on the conditions for triggering the collection of tandem mass spectra. Small changes in the signal intensity of a peptide in different LC-MS experiments can lead to the collection of a tandem mass spectrum in one experiment but not in another. Also, the quality of the tandem mass spectrometry experiments can vary, leading to successful identification in some cases but not in others. Using a novel image analysis approach, it is possible to achieve repeat analysis with a very high reproducibility by matching peptides across different LC-MS experiments using the retention time and parent mass over charge (m/z). It is also easy to confirm the final result visually. This approach has been investigated by using tryptic digests of integral membrane proteins from organelle-enriched fractions from Arabidopsis thaliana and it has been demonstrated that very highly reproducible, consistent, and reliable LC-MS data interpretation can be made. 相似文献
37.
Carpino PA Lefker BA Toler SM Pan LC Hadcock JR Murray MC Cook ER DiBrino JN DeNinno SL Chidsey-Frink KL Hada WA Inthavongsay J Lewis SK Mangano FM Mullins MA Nickerson DF Ng O Pirie CM Ragan JA Rose CR Tess DA Wright AS Yu L Zawistoski MP Pettersen JC DaSilva-Jardine PA Wilson TC Thompson DD 《Bioorganic & medicinal chemistry letters》2002,12(22):3279-3282
New tert-butyl, picolyl and fluorinated analogues of capromorelin (3), a short-acting growth hormone secretagogue (GHS), were prepared as part of a program to identify long-acting GHSs that increase 24-h plasma IGF-1 levels. Compounds 4c and 4d (ACD LogD values >or=2.9) displayed extended plasma elimination half-lives in dogs, primarily due to high volumes of distribution, but showed weak GH secretagogue activities in rats (ED(50)s>10 mg/kg). A less lipophilic derivative 4 (ACD LogD=1.6) exhibited a shorter canine half-life, but stimulated GH secretion in two animal species. Repeat oral dosing of 4 in dogs for 29 days (6 mg/kg) resulted in a significant down-regulation of the post dose GH response and a 60 and 40% increase in IGF-1 levels relative to pre-dose levels at the 8- and 24-h post dose time points. Compound 4 (CP-464709-18) has been selected as a development candidate for the treatment of frailty. 相似文献
38.
T Furre E S Bergstrand E Pedersen M Koritzinsky D R Olsen E O Hole E O Pettersen 《Radiation research》1999,152(1):76-82
Previous studies on human cervical cancer cells (NHIK 3025) have indicated that the cells, when X-irradiated in suspension, appeared to be more radiosensitive than when they were irradiated attached to glass dishes. However, this result depends on dosimetry, which is difficult in the situation where cells are attached to glass dishes due to backscattering electrons at the glass-liquid interface. Recently developed dosimetry that is based on detection of radiation-induced stable radicals in alanine and uses ESR spectroscopy offers a possibility for more relevant dosimetry at the glass-liquid interface than the previous estimates of doses based on Fricke dosimetry. Thin alanine films (>/=10 microm) were used to measure dose at the interface by irradiating the films while they were placed tightly against the bottom of dishes and covered with 1 mm of wax simulating the medium above cells. Fricke dosimetry was also performed, with different depths of Fricke solution in the dishes, to elucidate the contribution to the dose delivered by backscattering electrons at the glass-liquid interface. A dose rate of 1.9 Gy/min was measured with a thin layer (0.2-0.3 mm) of Fricke solution in petri dishes made of glass. However, this estimate appears to be too high, due to a contribution to dose by short-ranged electrons generated when the X rays passed through a steel lid 4.5 cm above the dishes. Dosimetry using alanine films resulted in dose rates of 1.15 and 0.87 Gy/min at the interfaces of glass-liquid and plastic- liquid, respectively. Hence there is a significant contribution to dose from backscattering electrons on dishes made of glass. The reason for our previous observation of a difference in radiosensitivity between cells irradiated in suspension and cells irradiated attached to glass appears to be a lack of accurate dosimetry at the glass-liquid interface. 相似文献
39.
40.
Daisuke Ojima Roger J. Pettersen Judith Wolkers Helge K. Johnsen Even H. Jrgensen 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2009,153(4):378-385
In a comparative experiment the effect of cortisol and growth hormone (GH) on the hypo-osmoregulatory ability of a landlocked and an anadromous strain of Arctic charr (Salvelinus alpinus) was investigated. Cortisol and GH were implanted either alone or in combination, and the fish were exposed to a 24 h seawater challenge test (SWT) on days 14 and 28 after implantation. Hypo-osmoregulatory ability, measured as plasma osmolality and chloride concentration after the SWTs, was better in the anadromous than in the landlocked strain, irrespective of treatment. However, cortisol provided a strong stimulation of hypo-osmoregualtory ability in both strains, and this stimulation seemed to be potentiated by GH in an additive manner. Improved hypo-osmoregulatory ability in GH + cortisol treated anadromous Arctic charr was accompanied by increased gill Na+, K+-ATPase activity and Na+–K+–2Cl− cotransporter protein abundance, but no changes in gill Na+,K+-ATPase α1a and α1b mRNA levels. For landlocked charr the improved hypo-osmoregulatory ability in GH +cortisol treated fish was accompanied only with an increase in gill Na+–K+–2Cl− cotransporter protein abundance. Hormone treatment caused an improvement of hypo-osmoregulatory ability that was of approximately the same magnitude in the landlocked as in the anadromous Arctic charr. This suggests that the lack of spontaneous development of hypo-osmoregulatory ability often seen in landlocked populations of Arctic charr may depend, at least partly, on a lack of the hormonal activation seen in anadromous populations. 相似文献