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OBJECTIVE: Malnutrition is responsible globally for 60% of deaths among children under 5 years and is often attributed to suboptimal feeding practices. In response, the World Health Organization recommends exclusive breast-feeding for the first 6 months of life. The objective of this study was to determine if an association exists between the early introduction of water and complementary foods (CFs) and the nutritional status of children in northern Senegal. DESIGN/SETTING/SUBJECTS: A cross-sectional study of 374 children in the Podor Health District between the ages of 6 and 23 months was conducted. Knowledge and behaviours of mothers regarding introduction of water and CFs were assessed via individual interviews. RESULTS: Water was introduced to about 85% of the children in the first 3 months of life and 62% were fed CFs before 6 months. Overall, 16% had clinically significant wasting (weight-for-length Z-score (WHZ) less than - 2) and 20% had stunting (height-for-age Z-score (HAZ) less than - 2). There was no significant association between wasting or stunting and introduction of water before 3 months (WHZ: odds ratio = 0.99, 95% confidence interval 0.46-2.14, P = 0.97; HAZ: 0.68, 0.34-1.36, P = 0.3) or introduction of CFs before 6 months (WHZ: 0.81, 0.46-1.42, P = 0.5; HAZ: 0.79, 0.46-1.35, P = 0.4). A significant association was found between wasting and male sex, age, living in Guede community, drinking river/pond water and large family size, while stunting was associated with age and drinking tap water. CONCLUSION: The results of the present study suggest that early introduction of water and CFs is frequent and is not associated with increased risk for malnutrition among children from this region of northern Senegal, but the possibility of reverse causality cannot be excluded.  相似文献   
23.

The widespread use of pesticides along with the simplification of the landscape has had undesirable effects on agroecosystems, such as the loss of biodiversity and the associated ecosystem service biological control. How current production systems can be remodelled to allow for a re-establishment of biological pest control, while preserving productivity, is a major challenge. Here, we tested whether a combination of tools could augment or synergize biological control of insect pests in apple (Malus domestica), comprised of a tortricid pest complex, a geometrid pest complex and the rosy apple aphid. The tools aimed at disrupting mating behaviour of multiple pest species (multispecies mating disruption, “Disrupt”, MMD), attracting natural enemies (a blend of herbivory-induced volatiles, “Attract”, A), or providing refuge and rewards for a diverse insect community (perennial flower strip, “Reward”, R) over a 3-year period. Suction samples were consistently richer in generalist predators but not in parasitoids when multiple tools including MMD?+?A?+?R or MMD?+?A were employed. In addition, lepidopteran pest levels were significantly lower in these plots than in MMD or MMD?+?R at the end of the 3-year experiment. This was, however, not reflected in survival of artificially established aphid colonies. Our data indicates that multiple, complementary tools can greatly enhance natural enemy level, but also that long-term implementation is needed to fully realize the augmentatory or synergistic potential of complementary components and restore biological control as an ecosystem service of practical relevance.

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24.
A 7-year-old dog was presented with a history of an open lesion on the right thoracic wall, discharging honey-like fluid and small stones. Ultrasonography and computed tomographic fistulography identified a cholecystocutaneous fistula; cholecystectomy was curative. Veterinarians should consider this disease in patients with long-term discharging lesions on the right thoracic or abdominal wall.  相似文献   
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This paper deals with the determination of the pore-size distribution of untreated and thermally modified twin samples of Norway spruce (Picea abies (L.) Karst.) and sycamore maple (Acer pseudoplatanus L.) by means of mercury intrusion porosimetry. The investigations considered oven-dried and at 22 °C and 95 % relative humidity-conditioned samples. A special sample holder and a novel method for evacuation were developed for the measurements. This was necessary both to ensure that samples were positioned at a defined distance and the conditioned samples did not dry in an uncontrolled manner. The results clearly show that the climatic state influences the results. Thermal modification greatly alters the pore-size distribution of spruce. This can be largely attributed to the formation of intercellular spaces in the middle lamella as a result of cell-wall compression due to thermal modification. The alteration of the pore structure of maple due to thermal modification is not as pronounced as that of spruce.  相似文献   
27.
  1. The protection of ecosystems with high diversity, such as coral reefs, is not an approach that guarantees their conservation. Thus, maintaining connectivity among coral populations over the long term is a strategy that should be adopted in order to protect diversity and ecological processes. Although coral reefs in Colombia are highly diverse, the population genetics baseline data of keystone species such as Orbicella faveolata are limited.
  2. To provide current information about the connectivity between populations of O. faveolata in the Colombian Caribbean, the genetic diversity and distribution of O. faveolata was evaluated with analysis of molecular variance (AMOVA), principal components, and migration estimations using 113 genets distributed in six populations. Also, a genetic structure analysis that included the available data for the Caribbean population was conducted, seeking to understand how the Colombian populations relate to the broader region.
  3. According to the global fixation index (FST) for the Colombian Caribbean, there was no genetic structure (FST = 0.002). Discriminant analysis of principal components (DAPC) showed that Corales del Rosario Archipelago (CR), Este de Isla Fuerte (EIF), San Bernardo Archipelago (SB), and Varadero Reef (VR) were grouped with Oeste de Isla Fuerte (OIF), with Bushnell (BS) representing the most divergent cluster. Migration analysis showed relatively high migration from VR to CR and SB, highlighting the importance of VR as a genetic reservoir for the region. Structure analysis showed that the Colombian population presented a specific genetic identity (FST = 0.254), suggesting that the Colombian Caribbean population could be a peripheral population that contributes significantly to genetic variation and is connected through a complex connectivity process.
  4. In conclusion, the estimated genetic connectivity reflects the influence of sea surface dynamics over the interpopulation exchange dynamics and the role of protected and nonprotected coral reef in the Colombian Caribbean. Thus, the Colombian Caribbean population of O. faveolata could be relevant to the conservation of genetic diversity on a larger scale.
  相似文献   
28.
The Prymnesiophycea Pavlova lutheriwas produced using a traditional technique (batch mode in carboys) and by an innovative technique (semi-continuous mode in alveolarphotobioreactor). Two experimental feedingtrials were carried out with Pacific oyster(Crassostrea gigas) larvae with freshand preserved (4 °C and 1 °C)P. lutheri concentrates used inmonospecific and bispecific diets, incombination with fresh Chaetoceroscalcitrans forma pumilum. Nodifferences in terms of gross composition andlarval performance were noticed between thefresh algae biomass produced by the twotechniques. The low temperatures allowedpreservation of the nutritionalcharacteristics of the P. lutheri freshculture for the time period considered (27days). The P. lutheri concentratespreserved at 4 °C or 1 °C didnot differ substantially in terms ofnutritional value. Larvae fed a monospecificdiet of P. lutheri, both fresh andpreserved, exhibited a modest growth rate (<2.1 µm day–1), in some cases notsignificantly different from that observed inthe unfed larvae (the control), and a lowsurvival rate. In contrast, when Chaetoceros calcitrans forma pumilumwas used as a monospecific diet, good growthperformance (>4.5 µm day–1) and ahigh survival rate (>86%) were observed inlarvae. A substitution of 50% (trial 1) or80% (trial 2) of fresh C. calcitransforma pumilum with the preserved P. lutheri concentrates did not adverselyaffect growth rate or survival of C.gigas larvae.  相似文献   
29.
A greenhouse rhizobox experiment was carried out to quantify the incorporation of 13C- and 15N-labelled rhizodeposits into different soil pools, especially into the rhizosphere microbial biomass, with increasing distances to the root surface of Lolium perenne. Five layers were analysed over 0-4.2 mm distance to an artificial root surface. C and N derived from rhizodeposition were 4.2% of total C and 2.8% of total N in soil at 0-1.0 mm distance and decreased rapidly with increasing distance. Microbial biomass C and N increased significantly towards the roots. At 0-1.0 mm distance microbial biomass C and N accounted for 66% and 29% of C and N derived from rhizodeposition, respectively. These percentages declined with increasing distance to the roots, but were still traceable up to 4.2 mm distance. Only small amounts of root released C and N were found in the 0.05 M K2SO4-extractable fraction. Extractable C and N derived from rhizodeposition varied around means of 4% of total C and N derived from rhizodeposition and increased only marginally with increasing distance to the roots. C derived from rhizodeposition in the non-extractable soil organic matter increased from 65 to 89% of total C derived from rhizodeposition at 0-3.4 mm distance. Conversely, microbial biomass C derived from rhizodeposition decreased from 33 to 4%. N derived from rhizodeposition in the non-extractable soil organic matter increased from 61 to 79% of total N derived from rhizodeposition at 0-2.6 mm distance, followed by a decline to roughly 55% in the two outer layers. Microbial biomass N decreased from 37 to 16% at 0-2.6 mm distance, followed by an increase to roughly 41% in the two outer layers. The C/N ratio of total C and N derived from rhizodeposition as well as that of extractable C and N derived from rhizodeposition increased with increasing distance to the roots to values above 30. In contrast, the C/N ratio of incorporated rhizodeposition C and N into the microbial biomass decreased to values less than 5 at 2.6-4.2 mm distance. The data indicate differential microbial response to C and N derived from rhizodeposition at a high spatial resolution from the root surface. The turnover of C and N derived from rhizodeposition in the rhizosphere as a function of the distance to the root surface is discussed.  相似文献   
30.
Cv. Star Ruby grapefruit (Citrus paradisi Macf.) were subjected to a 3-min dip in water at room temperature (20 degrees C) or at 50 degrees C with or without 25, 50, or 100 mg/L azoxystrobin (AZX). Then, the fruits were subjected to cold quarantine at 2 degrees C and 90-95% relative humidity (RH) for 3 weeks and then stored for 5 weeks at 8 degrees C and approximately 85% RH and for another 2 weeks at 20 degrees C and 80% RH to simulate a 2-week marketing period (SMP). No AZX residues were detected in the albedo and pulp following treatments at 20 or 50 degrees C, the total amount of residues being recovered from the flavedo tissue. There was a relationship between the AZX uptake in fruit and the amount of fungicide employed at 20 or 50 degrees C. When AZX was applied to the fruit at 25 mg/L at 20 degrees C, the residue level averaged 0.11 mg/kg (active ingredient, whole fruit basis). This residue concentration increased by 50 and 75% when the application rate increased from 25 to 50 or 100 mg/L, respectively. A similar pattern of accumulation was detected in fruit subjected to treatments at 50 degrees C. However, treatments at 50 degrees C produced residue levels higher than the treatments at 20 degrees C, with increases ranging from 63 to 84%, for the same concentration. Storage conditions did not affect the amount of AZX residues in the fruit. Treatment at 50 or 100 mg/L at 20 degrees C reduced the incidence of moderate to severe chilling injury (CI). Water dips at 50 degrees C reduced the incidence and severity of CI to a very low extent, with no additional advantages when hot water was used in combination with AZX. Treatments with 50 or 100 mg/L of AZX at 20 degrees C produced beneficial effects in decay control similar to those of 25 mg/L AZX at 50 degrees C or hot water alone. Better results were achieved with 50 or 100 AZX at 50 degrees C, providing complete control of decay during cold storage and with negligible decay after SMP. It was concluded that when AZX was applied at 50 degrees C, low doses of fungicide and minimal residue levels in fruit were required to control the postharvest decay of grapefruit. This treatment does not impair fruit quality and offers very interesting prospects for large scale application, due to the reduced potential toxicity of AZX to nontarget organisms and to the environment.  相似文献   
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