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1.
Persistence and efficacy of bifenthrin (25 and 50 g ai ha−1), fipronil (50 and 100 g ai ha−1) and indoxacarb (70 and 140 g ai ha−1) has been studied in okra fruits. The initial deposits varied from 0.259–0.382 μg g−1 at low and 0.461–0.688 μg g−1 at high rate of application. The residues persisted upto 10 days with half-life of 1.32–1.58 days for bifenthrin, 0.65–1.12 days for fipronil and 0.58–1.02 days for indoxacarb. Based on ADI, the suggested waiting period was 1 day for bifenthrin and indoxacarb and 3 days for fipronil. All the insecticides were found effective against leafhopper and shoot and fruit borer.  相似文献   

2.
In natural environment with ambient air, ginkgo trees emitted volatile organic compounds 0.18 μg g−1 h−1 in July, and 0.92 μg g−1 h−1 in September. Isoprene and limonene were the most abundant detected compounds. In September, α-pinene accounted for 22.5% of the total. Elevated CO2 concentration in OTCs increased isoprene emission significantly in July (p < 0.05) and September (p < 0.05), while the total monoterpenes emission was enhanced in July and decreased in September by elevated CO2. Exposed to elevated O3 increased the isoprene and monoterpenes emissions in July and September, and the total volatile organic compounds emission rates were 0.48 μg g−1 h−1 (in July) and 2.24 μg g−1 h−1 (in September), respectively. The combination of elevated CO2 and O3 did not have any effect on biogenic volatile organic compounds emissions, except increases of isoprene and Δ3-carene in September. Foundation item: The National Natural Science Foundation of China (No. 90411019).  相似文献   

3.
Uptake rates for dissolved nitrogen (DN) by a marine alga (Oocystis borgei) were examined in a 15N tracer experiment. Maximal uptake rates for all forms of DN were observed at temperatures between 25 and 30°C and at algal concentrations between 3.22 × 108 and 4.78 × 10cell L−1. Light intensity required to achieve the maximal uptake rate was 45 μmol m−2 s−1 for dissolved inorganic nitrogen (DIN = NO3 , NO2 , NH4 +) and methionine, and 126 μmol m−2 s−1 for urea. Salinity required to achieve the maximal uptake rate was 12.85 ppt for DIN, 19.89 ppt for urea and 26.2 ppt for methionine.  相似文献   

4.
Intermittent preventive treatment in pregnancy with sulphadoxine−pyrimethamine (IPTp-SP) is one of the main strategies for protecting pregnant women, fetus, and their new-born against adverse effects of P. falciparum infection. The development of the drug resistance linked to mutations in P. falciparum dihydrofolate reductase gene (pfdhfr) and P. falciparum dihydropteroate synthase gene (pfdhps), is currently threatening the IPTp-SP approach. This study determined the prevalence of pfdhfr and pfdhps mutations in isolates obtained from pregnant women with asymptomatic P. falciparum infection in Nigerian. Additionally, P. falciparum genetic diversity and multiplicity of infection (MOI) was assessed by genotyping the P. falciparum merozoite surface Protein 1 and 2 (pfmsp-1 and pfmsp-2) genes. The pfdhfr and pfdhps were genotyped by direct sequencing, and the pfmsp-1 and pfmsp-2 fragment analysis by polymerase chain reaction was used to determine P. falciparum genetic diversity. Of the 406 pregnant women recruited, 123 had P. falciparum infection by PCR, and of these, 52 were successfully genotyped for pfdhfr and 42 for pfdhps genes. The pfdhfr triple-mutant parasites (N51I, C59R, and S108N) or the IRN haplotype were predominant (98%), whereas pfdhfr mutations C50R and I164L did not occur. For pfdhps gene, the prevalence of A437G, A581G, A436A, and A613S mutations were 98, 71, 55, and 36%, respectively. Nineteen (44%) isolates with quintuple mutations (CIRNI- SGKGA) had the highest combined pfdhfr-pfdhps haplotype. Isolates with sextuple mutants; CIRNI- AGKAS and CIRNI- AGKGA had a prevalence of 29 and 14%, respectively. High genetic diversity (7 pfmsp-1 alleles and 10 pfmsp-2 alleles) and monoclonal infection rate (76%) was observed. This study demonstrated a continuous high prevalence of pfdhfr mutation and an increase in pfdhps mutations associated with SP-resistance in southwest Nigeria. Continuous surveillance of IPTp-SP effectiveness and consideration of alternative IPTp strategies is recommended.  相似文献   

5.
  • ○ 1.1 Definitions of ‘ethnic groups’ and ‘ethnicity’
  • ○ 1.2 Demographics and characteristics of minority ethnic groups in the UK
    • – Countries of origin
    • – Age/sex distribution and life expectancy
    • – Geographical distribution and size of household
    • – Religious beliefs
    • – Education and employment patterns
    • Key points
  • 2 Overview of the health profile and dietary habits of minority ethnic groups in the UK
    • ○ 2.1 Available surveys
    • ○ 2.2 Overview of the health profiles among adults from minority ethnic groups
      • – Overall health
      • – Cardiovascular disease (CVD)
      • – Coronary heart disease (CHD)
      • – Stroke
      • – Type 2 diabetes
      • – Obesity
    • ○ 2.3 Possible causes of increased disease risk among minority ethnic groups
    • ○ 2.4 Smoking, drinking and physical activity habits
    • ○ 2.5 Dietary habits and nutritional status
    • ○ 2.6 Overview of the health profiles and dietary and health behaviour patterns of children from minority ethnic groups
      • – Overall health
      • – Diet and health behaviour patterns
    • ○ 2.7 Gaps in data availability
      • – Income and socio‐economic status
      • – Food availability and access
      • – Awareness of healthy eating
      • – Religious beliefs
      • – Food beliefs
      • – Time and cooking skills
      • – Generation and gender
      • Key points
    • 4 Traditional diets of minority ethnic groups
      • ○ 4.1 Overview of traditional diets of minority ethic groups
        • – South Asians
        • – African‐Caribbeans
        • – Chinese
      • ○ 4.2 Dietary acculturation
      • ○ 4.3 Nutritional composition of ethnic‐style cuisine
        • ○ 5.1 Effective nutritional interventions
        • ○ 5.2 Health promotion interventions to prevent problems associated with fasting
        • ○ 5.3 Priorities for nutritional interventions and health promotion
        • ○ 5.4 Using behaviour change models
        • ○ 5.5 Current community initiatives
        • ○ 5.6 Catering for institutionalised individuals
        • ○ 5.7 Recommendations for future research, policy and practice
            相似文献   

  • 6.
    Relative metal-ligand complex stability is predicted by evaluating the relationships between physicochemical properties of metal ions and their experimental biotic and abiotic binding constants, K. Linear regression analysis showed that the softness index (σp) and the covalent index (χ2mr) were especially useful in model construction for rainbow trout (Oncorhynchus mykiss), fathead minnows (Pimephales promelas) and crustaceansaquatic (Daphnia magna) based on RMSE and F-ratio criterion (Fobserved/Fcritical of ≥4). The absolute value of the log of the first hydrolysis constant |log KOH| correlated best with log K values for barley (R2=0.74, p=0.02) and earthworm (R2=0.82, p=0.01). In contrast, the ionic index Z2/r explained most of the variability of log K values for the two clays kaolinite and montmorillonite, while |log KOH| was a better predictor of the generic NICA-Donnan parameters for HA and FA (0.67<R2<0.80, 0.002<p<0.01). This implies dissimilarity of the nature of the binding sites on biotic and chemical ligands and the different binding mechanisms between metal and ligands.  相似文献   

    7.
    Potatoes (Solanum tuberosum L.) from the high Tiber valley area (TVA; Tuscany, Italy), have been sampled and analyzed for selected mineral content (Na, Mg, K, Ca, and Mn, Fe, Cu and Zn) and vitamin C, the year 2012; some samples from 2011 and 2013 crops were also collected and analyzed. The varieties were Daytona (DAY), Kennebec (KEN), Sifra (SIF) and Volare (VOL). Control samples consisted of mixed commercial varieties from the local market, namely C1, C2 and C3. The low content of sodium, especially for KEN (46 ± 3 mg/kg FD (freeze dry), year 2012) and SIF (47 ± 3) (VOL (55 ± 3) and DAY (61 ± 3) have a little higher values) is worth of note and in agreement with the scarce concentration of Na in the soil (291 ± 12 mg/kg DM). Magnesium was abundant in KEN (1434 ± 75 mg/kg FD, year 2012) and VOL (1334 ± 70). The content of K for DAY and KEN (13,147 ± 900 and 13,185 ± 900 mg/kg FD) was higher than for VOL and SIF; whereas Ca was in the range 340 ± 16–490 ± 28 mg/kg FD. The contents of Cu and Zn were higher in KEN (8.1 ± 0.3 and 25 ± 1 mg/kg FD) when compared to the other varieties and controls. The content of vitamin C is high for KEN and SIF and decreased significantly upon cooking (50% for KEN).  相似文献   

    8.
    Following single application of Nativo 75 WG (trifloxystrobin 25 % + tebuconazole 50 %) on wheat crop @ 300 and 600 g ha−1, resulting in active application of trifloxystrobin @ 75.0 and 150.0 g a.i. ha−1 and tebuconazole @ 150 and 300 g a.i. ha−1, the average initial deposits of trifloxystrobin on wheat leaves were 5.54 and 8.30 mg kg−1, and that of tebuconazole were 14.66 and 27.94 mg kg−1, respectively. Half-life values for trifloxystrobin were observed to be 2.80 and 2.51 days whereas those for tebuconazole were found to be 2.46 and 1.85 days at recommended and double the recommended dosages, respectively. The residues of trifloxystrobin and tebuconazole dissipated to the extent of >89 % at both the dosages after 7 days. Wheat grain samples at harvest having pre harvest interval of 140 days did not show the presence of trifloxystrobin and tebuconazole at their determination limit of 0.01 mg kg−1.  相似文献   

    9.
    The total nitrogen (TN) and water-soluble nitrogenous ions were determined by using CHN Elemental Analyzer and ion chromatography method, respectively, from November 24, 1998 to February 12, 1999 in Beijing. The average concentrations of TN, NH4 + and NO3 were 10.62 μg N m−3, 6.67 μg m−3 and 10.01 μg m−3, respectively. The total inorganic nitrogen (IN) calculated from NH4 + and NO3 was 7.45 μg N m−3, accounting for 70% of TN, i.e., 30% of TN existed as organic nitrogen form (ON). The correlation between ON and other pollution tracers showed that, coal combustion, biomass burning, soil humic matter and secondary formation were the important sources of ON in particulate matter in Beijing.  相似文献   

    10.
    Edwardsiella ictaluri causes enteric septicemia in fish. Recently, we reported construction of E. ictaluri mutants with single and double gene deletions in tricarboxylic acid cycle (TCA) and one-carbon (C-1) metabolism. Here, we report the tissue persistence, virulence, and vaccine efficacy of TCA cycle (EiΔsdhC, EiΔfrdA, and EiΔmdh), C-1 metabolism (EiΔgcvP and EiΔglyA), and combination mutants (EiΔfrdAΔsdhC, EiΔgcvPΔsdhC, EiΔmdhΔsdhC, and EiΔgcvPΔglyA) in channel catfish. The tissue persistence study showed that EiΔsdhC, EiΔfrdA, EiΔfrdAΔsdhC, and EiΔgcvPΔsdhC were able to invade catfish and persist until 11 days post-infection. Vaccination of catfish fingerlings with all nine mutants provided significant (P < 0.05) protection against subsequent challenge with the virulent parental strain. Vaccinated catfish fingerlings had 100% survival when subsequently challenged by immersion with wild-type E. ictaluri except for EiΔgcvPΔglyA and EiΔgcvP. Mutant EiΔgcvPΔsdhC was found to be very good at protecting catfish fry, as evidenced by 10-fold higher survival compared to non-vaccinated fish.  相似文献   

    11.
    Concentrations of metals were determined in the gills, liver, kidney, heart and muscle in Capoeta umbla caught from six stations from the Munzur River system. Metal concentrations in the tissues tended to vary significantly among stations (p < 0.05). Liver (Cu, 10.10 ± 0.23–23.03 ± 9.37 ppm; Zn, 14.67 ± 3.01–21.82 ± 2.39 ppm; Cd, 18.04 ± 4.56–52.69 ± 10.65 ppb and Fe, 28.87 ± 6.78–115.11 ± 34.87 ppm) and kidney (Cu, 1.80 ± 0.25–3.70 ± 0.62 ppm; Zn, 20.81 ± 0.37–29.36 ± 0.70 ppm; Cd, 132.06 ± 5.29–639.51 ± 20.14 ppb and Fe, 24.40 ± 1.98–59.39 ± 1.97 ppm) tissues showed higher metal concentrations than other tissues. It seems that metal contamination in the river is too high for the health of fish and the people who eat them. The geographical locations of catch, season, nature of diet, and the size of fish used for analyses might lead to different metal concentration in the same fish species.  相似文献   

    12.
    Nitrate-rich food can increase nitric oxide production and improve vascular and brain functions. This study examines the feasibility of a randomised controlled trial (RCT) testing the effects of prolonged consumption of different doses of dietary nitrate (NO3) in the form of beetroot juice (BJ) in overweight and obese older participants. A single-blind, four-arm parallel pilot RCT was conducted in 62 overweight and obese (30.4 ± 4 kg/m2) older participants (mean ± standard deviation (SD), 66 ± 4 years). Participants were randomized to: (1) high-NO3 (HN: 2 × 70 mL BJ/day) (2) medium-NO3 (MN: 70 mL BJ/day), (3) low-NO3 (LN: 70 mL BJ on alternate days) or (4) Placebo (PL: 70 mL of NO3-depleted BJ on alternate days), for 13 weeks. Compliance was checked by a daily log of consumed BJ, NO3 intake, and by measuring NO3 and NO2 concentrations in plasma, saliva, and urine samples. Fifty participants completed the study. Self-reported compliance to the interventions was >90%. There were significant positive linear relationships between NO3 dose and the increase in plasma and urinary NO3 concentration (R2 = 0.71, p < 0.001 and R2 = 0.46 p < 0.001, respectively), but relationships between NO3 dose and changes in salivary NO3 and NO2 were non-linear (R2 = 0.35, p = 0.002 and R2 = 0.23, p = 0.007, respectively). The results confirm the feasibility of prolonged BJ supplementation in older overweight and obese adults.  相似文献   

    13.
    This paper reviews the role of the HBSC study in Scotland and suggests that the HBSC study has growing status and relevance in Scotland for a number of reasons as it continues to provide insights for politicians, policy makers, education professionals and health promotion practitioners. The paper will set out the historical background to the HBSC study and the associated research and health promoting school developments in Scotland. It will explore the factors that have been important in its influential role in contributing to health promotion policy developments in the education and health sectors in Scotland. It is suggested that this role has been shaped by:
    –  The changing political context and the developing political will to improve Scotland’s health.
    –  The close practical links between the HBSC study and the national agency for health promotion.
    –  The growing credibility of the study in the education sector in Scotland as well as the health sector.
    –  The growing evidence of the study’s influence through:
    –  references to the study in government reports;
    –  representation of HBSC researchers on government policy and strategy committees;
    –  deputy chief medical Officer being on HBSC committee;
    –  increased use of HBSC outputs in schools and education authorities;
    –  linked developments in the health promoting schools movement in Scotland.
    –  The development of a training and capacity building resource for teachers which draws extensively on data from the HBSC study.
    –  The continuity of the study over nineteen years resulting in a unique and valued data set.
    –  The development of good communication strategies which has resulted in high awareness of the data in the education and health sectors and the Scottish media.
    –  The growing understanding that HBSC is an important international study and that Scotland has played a significant role in co-ordinating the international dimension of the study and the close links between Scotland and the European Regional Office of The World Health Organization (WHO).
      相似文献   

    14.
    Objectives Infant birth weight is influenced by modifiable maternal pre-pregnancy behaviors and characteristics. We evaluated the relationship among pre-pregnancy body mass index (BMI), gestational weight gain, and infant birth weight, in a prospective cohort study. Methods Women were enrolled at ≤20 weeks gestation, completed in-person interviews and had their medical records reviewed after delivery. Infant birth weight was first analyzed as a continuous variable, and then grouped into Low birth weight (LBW) (<2,500 g), normal birth weight (2,500–3,999 g), and macrosomia (≥4,000 g) in categorical analysis. Pre-pregnancy BMI and gestational weight gain were categorized based on Institute of Medicine BMI groups and gestational weight gain guidelines. Associations among infant birth weight and pre-pregnancy BMI, gestational weight gain, and other factors were evaluated using multivariate regression. Risk ratios were estimated using generalized linear modeling procedures. Results Pre-pregnancy BMI was independently and positively associated with infant birth weight (β = 44.7, P = 0.001) after adjusting for confounders, in a quadratic model. Gestational weight gain was positively associated with infant birth weight (β = 19.5, P < 0.001). Lower infant birth weight was associated with preterm birth (β = −965.4, P < 0.001), nulliparity (β = −48.6, P = 0.015), and female babies (β = −168.7, P < 0.001). Less than median gestational weight gain was associated with twice the risk of LBW (RR = 2.04, 95% CI 1.34–3.11). Risk of macrosomia increased with increasing pre-pregnancy BMI and gestational weight gain (P for linear trend <0.001). Conclusions These findings support the need to balance pre-pregnancy weight and gestational weight gain against the risk of LBW and macrosomia among lean and obese women, respectively.  相似文献   

    15.
    The existence of children living at high altitude suffering from lead (Pb) poisoning prompted us to investigate the long term effects of this pollutant on growth and bone biology in growing rats maintained at simulated high altitude (SHA). Pb and hypoxia (HX) significantly reduced body weight (−9.4 % and −24 %; p < 0.01) and length (−3 % and −8 %; p < 0.01); decreased femoral ultimate load (−16 % and −40 %; p < 0.01) and femoral energy absorption capacity (−18 % and −74 %; p < 0.01). Oral pathologic alterations were observed in experimental groups. Our findings revealed growth retardation and damages on femoral and mandibular bones that predispose to fractures.  相似文献   

    16.
    The effect of bread consumption on overall food intake is poorly understood. The aim of this study was to measure postprandial food intake after a set breakfast containing three different breads. Ten males and 10 females aged 20.1–44.8 years, BMI 18.4–24.8 kg/m2, consumed two slices of White Bread, Bürgen® Wholemeal and Seeds Bread or Lupin Bread (all 1300 kJ) with 10 g margarine and 30 g strawberry jam. Fullness and hunger responses and were measured before and during the test breakfasts. Glucose and insulin responses (incremental area under each two-hour curve (iAUC)) were calculated. Food intake was measured and energy and nutrient intake determined at a buffet meal two hours later. Subjects consumed significantly less energy after the Bürgen® Bread meal compared to the White Bread meal (2548 ± 218 vs. 3040 ± 328 kJ, Bürgen® Bread vs. White Bread, P < 0.05). There were higher fullness responses for the Lupin Bread (P < 0.01), and the Bürgen® Bread (P < 0.05) compared with the White Bread. Lupin Bread and Bürgen® Bread produced smaller postprandial glucose responses (79 ± 7, 74 ± 4, 120 ± 10 mmol/L min iAUC, Lupin, Bürgen® and White Bread respectively, P < 0.01). Differences in insulin responses were also observed (6145 ± 1048, 6471 ± 976, 9674 ± 1431 pmol/L min iAUC, Lupin, Bürgen® and White Bread respectively, P < 0.01). Equal-energy portions of three different commercially available breads differed in their short-term satiation capacity. Further studies are needed to demonstrate any potential benefit for weight management.  相似文献   

    17.
    Background: Glyphosate (GLY) is the most heavily used herbicide in the world. Despite nearly ubiquitous exposure, few studies have examined prenatal GLY exposure and potentially adverse pregnancy outcomes. Preterm birth (PTB) is a risk factor for neonatal mortality and adverse health effects in childhood.Objectives: We examined prenatal exposure to GLY and a highly persistent environmental degradate of GLY, aminomethylphosphonic acid (AMPA), and odds of PTB in a nested case–control study within the ongoing Puerto Rico Testsite for Exploring Contamination Threats (PROTECT) pregnancy cohort in northern Puerto Rico.Methods: GLY and AMPA in urine samples collected at 18±2 (Visit 1) and 26±2 (Visit 3) wk gestation (53 cases/194 randomly selected controls) were measured using gas chromatography tandem mass spectrometry. Multivariable logistic regression was used to estimate associations with PTB (delivery <37wk completed gestation).Results: Detection rates in controls were 77.4% and 77.5% for GLY and 52.8% and 47.7% for AMPA, and geometric means (geometric standard deviations) were 0.44 (2.50) and 0.41 (2.56)μg/L for GLY and 0.25 (3.06) and 0.20 (2.87)μg/L for AMPA, for Visits 1 and 3, respectively. PTB was significantly associated with specific gravity–corrected urinary GLY and AMPA at Visit 3, whereas associations with levels at Visit 1 and the Visits 1–3 average were largely null or inconsistent. Adjusted odds ratios (ORs) for an interquartile range increase in exposure at Visit 3 were 1.35 (95% CI: 0.99, 1.83) and 1.67 (95% CI: 1.26, 2.20) for GLY and AMPA, respectively. ORs for Visit 1 and the visit average were closer to the null.Discussion: Urine GLY and AMPA levels in samples collected near the 26th week of pregnancy were associated with increased odds of PTB in this modestly sized nested case–control study. Given the widespread use of GLY, multiple potential sources of AMPA, and AMPA’s persistence in the environment, as well as the potential for long-term adverse health effects in preterm infants, further investigation in other populations is warranted. https://doi.org/10.1289/EHP7295  相似文献   

    18.
    19.
    Novel series of bicyclic pyrrolo[1,2-c]pyrimidines 3ag, 5, 6a, b, and 7a, b, tricyclic pyrimido[5,4-e]pyrrolo[1,2-c]pyrimidines 8ac, 9ag, 13ac, 17, 18a, b, 19, 20a,b and 21 and tetracyclic condensed pyrimidines 14, 22 and 23 were synthesized through different chemical reactions. Structures of all synthesized pyrimidine derivatives were supported by spectral and elemental analyses. Analgesic activity evaluation was carried out using acetic acid-induced writhing assay, and all compounds exerted comparable activity to indomethacin. The anti-inflammatory activity evaluation was performed using carrageenan-induced paw edema in rats, the potency of the bicyclic derivatives 3af and 7b revealed comparable activity to indomethacin without gastric ulceration. The tricyclic derivatives 13a and 20a exerted good activity, however, they induced gastric ulcers while 13b and 13c showed moderate activity without ulceration. In case of tetracyclic derivatives, compound 14 exhibited the highest potency and safety profile.  相似文献   

    20.
    We identified dish-based dietary patterns for breakfast, lunch, and dinner and assessed the diet quality of each pattern. Dietary data were obtained from 392 Japanese adults aged 20–69 years in 2013, using a 4 d dietary record. K-means cluster analysis was conducted based on the amount of each dish group, separately for breakfasts (n = 1462), lunches (n = 1504), and dinners (n = 1500). The diet quality of each dietary pattern was assessed using the Healthy Eating Index 2015 (HEI-2015) and Nutrient-Rich Food Index 9.3 (NRF9.3). The extracted dietary patterns were as follows: ‘bread-based’ and ‘rice-based’ for breakfast; ‘bread’, ‘rice-based’, ‘ramen’, ‘udon/soba’, and ‘sushi/rice bowl dishes’ for lunch; and ‘miscellaneous’, ‘meat dish and beer’, and ‘hot pot dishes’ for dinner. For breakfast, the HEI-2015 and NRF9.3 total scores were higher in the ‘rice-based’ pattern than the ‘bread-based’ pattern. For lunch, the HEI-2015 and NRF9.3 total scores were relatively high in the ‘rice-based’ pattern and low in the ‘ramen’ pattern. For dinner, the HEI-2015 total score was the highest in the ‘meat dish and beer’ pattern, and the NRF9.3 total score was higher in the ‘hot pot dishes’ than the ‘miscellaneous’ pattern. These results suggested that breakfast, lunch, and dinner have distinctive dietary patterns with different diet qualities.  相似文献   

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