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61.
Responding to different questions generated by biodiversity and ecosystem services policy or management requires different forms of knowledge (e.g. scientific, experiential) and knowledge synthesis. Additionally, synthesis methods need to be appropriate to policy context (e.g. question types, budget, timeframe, output type, required scientific rigour). In this paper we present a range of different methods that could potentially be used to conduct a knowledge synthesis in response to questions arising from knowledge needs of decision makers on biodiversity and ecosystem services policy and management. Through a series of workshops attended by natural and social scientists and decision makers we compiled a range of question types, different policy contexts and potential methodological approaches to knowledge synthesis. Methods are derived from both natural and social sciences fields and reflect the range of question and study types that may be relevant for syntheses. Knowledge can be available either in qualitative or quantitative form and in some cases also mixed. All methods have their strengths and weaknesses and we discuss a sample of these to illustrate the need for diversity and importance of appropriate selection. To summarize this collection, we present a table that identifies potential methods matched to different combinations of question types and policy contexts, aimed at assisting teams undertaking knowledge syntheses to select appropriate methods.  相似文献   
62.
Under the changing climate, asymmetric warming pattern would be more likely during day and night time, instead of symmetric one. Concurrently, the growth responses and water use of plants may be different compared with those estimated based on symmetric warming. In this work, it was compared with the effects of symmetric (ETs) and asymmetric (ETa) elevation of temperature alone, and in interaction with elevated carbon dioxide concentration (EC), on the grain yield (GY) and evapotranspiration in winter wheat (Triticum aestivum L.) based on pot experiment in the North China Plain (NCP). The experiment was carried out in six enclosed‐top chambers with following climate treatments: (1) ambient temperature and ambient CO2 (CON), (2) ambient temperature and elevated CO2 (EC), (3) elevated temperature and ambient CO2 (ETs; ETa), and (4) elevated temperature and elevated CO2 (ECETs, ECETa). In symmetric warming, temperature was increased by 3°C and in asymmetric one by 3.5°C during night and 2.5°C during daytime, respectively. As a result, GY was in ETa and ETs 15.6 (P < 0.05) and 10.3% (P < 0.05) lower than that in CON. In ECETs and ECETa treatments, GY was 14.9 (P < 0.05) and 9.1% (P < 0.05) higher than that in CON. Opposite to GY, evapotranspiration was 7.8 (P < 0.05) and 17.9% (P < 0.05) higher in ETa and ETs treatments and 7.2 (P < 0.05) and 2.1% (P > 0.05) lower in ECETs and ECETa treatments compared with CON. Thus, GY of wheat could be expected to increase under the changing climate with concurrent elevation of CO2 and temperature as a result of increased WUE under the elevated CO2. However, the gain would be lower under ETa than that estimated based on ETs due to higher evapotranspiration.  相似文献   
63.

Background  

During the course of a bacterial infection, the rapid identification of the causative agent(s) is necessary for the determination of effective treatment options. We have developed a method based on a modified broad-range PCR and an oligonucleotide microarray for the simultaneous detection and identification of 12 bacterial pathogens at the species level. The broad-range PCR primer mixture was designed using conserved regions of the bacterial topoisomerase genes gyrB and parE. The primer design allowed the use of a novel DNA amplification method, which produced labeled, single-stranded DNA suitable for microarray hybridization. The probes on the microarray were designed from the alignments of species- or genus-specific variable regions of the gyrB and parE genes flanked by the primers. We included mecA-specific primers and probes in the same assay to indicate the presence of methicillin resistance in the bacterial species. The feasibility of this assay in routine diagnostic testing was evaluated using 146 blood culture positive and 40 blood culture negative samples.  相似文献   
64.
The seabuckthorn carpenter moth, Holcocerus hippophaecolus, which has a generation time of four years, is recently becoming one of the major pests of the seabuckthorn (Hippophae rhamnoides) in Inner Mongolia, Liaoning, Shanxi, Ningxia and Shaanxi of China (Hua et al., 1990). The larvae of the H. hippophaecolus mainly damage the stems and roots of the seabuckthorn, and the mature larvae pupate in the soil. The spatial distribution of the pupae was analyzed by using biostatistics and geostatistics in order to effectively control the insect and further study the spatial distribution of the population. Results show that most of the pupae (90%) had an eclosion time span from early June to the end of July. The sex ratio of the pupae was nearly 1:1 in the woodland samples. In addition, 24.3% of the 971 trees investigated had pupae and it ranged from 0 to 4 per tree within a distance of 1.3 m from the base of the stem. 90% of the pupae were aggregated within a distance of 1 m from the base of the stem. The pupae show intense spatial aggregation in the sampled woodland which had an 11.1 m spatial dependence and a 90.7% intensity in the local spatial continuity. Moreover, the population presented an intensive spotted distribution and many aggregated spots were found in the woodlands. As for the relationship between grid size and variogram of the pupae, the variations in the range, the intensity of local spatial continuity and the sill were all very low or non-existent when the grid size was 5 m, 6 m or 7 m. Whereas, the value of the decisive coefficient was the biggest when the grid size was 5 m making it the ideal grid size.  相似文献   
65.
杨萍  邓合黎  漆波  刘琼 《生态学报》2005,25(3):543-554
研究于 1998~ 2 0 0 3年在库区 10个区县 ,35个调查点进行。研究时 ,库区蝴蝶的生活环境被划分为 80个小生境 ,设置样带6 6 1条 ;调查期间获得 (Sampled)蝴蝶 331种 ,10 780只个体。报道三峡库区蝴蝶群落的部分参数 :2 5 3种蝴蝶的小生境占有率低于 10 % ,占有 4 0 %以上小生境的蝴蝶只有 7种 ;在 6 0条以上样带都获得的蝴蝶有 16种 ,而在 10条以下样带内获得的蝴蝶 2 19种 ,占总数的 6 6 .2 % ;优势种 2 1个 (6 .3% ) ,常见种 12 5个 (37.8% ) ,少见种 10 3个 (31.1% ) ,罕见种 82个 (2 4 .8% ) ;相对多度高于 1%的种类 2 2个 ,仅占总数的 6 .6 % ;个体数分布的规律接近对数级数法则。三峡库区蝶类现在的分布反映了库区生境破碎化的结果 ,意味着适宜的生境斑块周围分布不适宜生境 ,种群受到面积、隔离、边缘等多种效应的影响 ,形成了现有的物种多样性及其空间格局  相似文献   
66.
67.

Objective

To investigate associations between morbidity and global life satisfaction in postmenopausal women taking into account type and number of diseases.

Materials and Methods

A total of 11,084 women (age range 57–66 years) from a population-based cohort of Finnish women (OSTPRE Study) responded to a postal enquiry in 1999. Life satisfaction was measured with a 4-item scale. Self-reported diseases diagnosed by a physician and categorized according to ICD-10 main classes were used as a measure of morbidity. Enquiry data on health and lifestyle were used as covariates in the multivariate logistic models.

Results

Morbidity was strongly associated with life dissatisfaction. Every additional disease increased the risk of life dissatisfaction by 21.1% (p < .001). The risk of dissatisfaction was strongest among women with mental disorders (OR = 5.26; 95%CI 3.84–7.20) and neurological disorders (OR = 3.62; 95%CI 2.60–5.02) compared to the healthy (each p < .001). Smoking, physical inactivity and marital status were also associated with life dissatisfaction (each p < .001) but their introduction to the multivariate model did not attenuate the pattern of associations.

Conclusions

Morbidity and life dissatisfaction have a disease-specific and dose-dependent relationship. Even if women with mental and neurological disorders have the highest risk for life dissatisfaction, monitoring life satisfaction among aging women regardless of disorders should be undertaken in order to intervene the joint adverse effects of poor health and poor well-being.  相似文献   
68.
Summary Larvae of Panolis flammea and Bupalus piniarius were reared in the laboratory on needles of Scots pine affected by industrial air pollutants in Finland. Needles were collected at different distances from a distinctive source of emission along two 9-km-long transects, and from independent control plots. The elemental composition of the needles used as larval food was analysed. Pupal weight, length and width were negatively correlated wiht the distance from the source of emission. The elemental composition of the pine needles explained 24–53% of the variation in pupal weight. Most of the explained variation was assoicated with the concentration of heavy meals in the pine needles.  相似文献   
69.
OBJECTIVE--To investigate the effect of overweight on premature mortality and work disability in young and middle aged Finns. DESIGN--Prospective cohort study based on data collected in the multiphasic health examinations by the Social Insurance Institution of Finland from 1966 to 1972 and follow up until 1982. SETTING--34 Communities throughout Finland. SUBJECTS--12,053 Women and 19,076 men who were employed and aged 25-64 at baseline. MAIN OUTCOME MEASURES--Mortality and work disability pensions from all and specified causes. RESULTS--Body mass index was a weak predictor of death but a strong predictor of early work disability, which increased linearly with body mass index. After adjustment for age, geographical region, occupation, and smoking the relative risks of work disability for women and men with a body mass index greater than or equal to 30 kg/m2 were, respectively, 2.0 (95% confidence interval 1.8 to 2.3) and 1.5 (1.3 to 1.7) when compared with those of subjects with body mass index less than 22.5 kg/m2. The increased risks were due to an excess of cardiovascular and musculoskeletal diseases but not of mental diseases. One fourth of all disability pensions from cardiovascular and musculoskeletal causes in women and half as many in men could be attributed to overweight (body mass index greater than 25 kg/m2) alone. CONCLUSIONS--Though modest overweight has little impact on mortality it predicts severe functional impairment. A considerable proportion of work disability pensions could probably be prevented by efficient weight control.  相似文献   
70.
The combined stress of high temperature and high relative air humidity is one of the most serious agrometeorological disasters that restricts the production capacity of protected agriculture. However, there is little information about the precise interaction between them on tomato fruit quality. The objectives of this study were to explore the effects of the combined stress of high temperature and relative humidity on the sugar and acid metabolism and fruit quality of tomato fruits, and to determine the best relative air humidity for fruit quality under high temperature environments. Four temperature treatments (32°C, 35°C, 38°C, 41°C), three relative air humidity (50%, 70%, 90%) and four duration (3, 6, 9, 12 d) orthogonal experiments were conducted, with 28°C, 50% as control. The results showed that under high temperature and relative air humidity, the activity of sucrose metabolizing enzymes in young tomato fruits changed, which reduced fruits soluble sugar content; in addition, enzyme activities involved phosphopyruvate carboxylase (PEPC), mitochondria aconitase (MDH) and citrate synthetase (CS) increased which increased the content of organic acids (especially malic acid). Eventually, vitamin C, total sugar and sugar-acid ratio decreased significantly, while the titratable acid increased, resulting in a decrease in fruit flavor quality and nutritional quality in ripe fruit. Specifically, a temperature of 32°C and a relative air humidity of 70% were the best cultivation conditions for tomato reproductive growth period under high temperature. Our results indicating that fruit quality reduced under high temperature at the flowering stage, while increasing the relative air humidity to 70% could alleviate this negative effect. Our results are benefit to better understand the interaction between microclimate parameters under specific climatic conditions in the greenhouse environment and their impact on tomato flavor quality.  相似文献   
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