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1.
The ZeroFly® Storage Bag is a woven polypropylene bag (PP) that has deltamethrin incorporated in its fibers, and represents a novel approach to reducing stored-product insect pest-related postharvest losses. Fabric samples from ZeroFly bags, polypropylene (PP) bags, jute bags, malathion-treated PP bags, malathion-treated jute bags and GrainPro bags were affixed to the bottom of 9-cm Petri dishes and 20 adults of either Sitophilus oryzae (L.) or Tribolium castaneum (Herbst) were introduced to determine contact sensitivity of insects exposed to ZeroFly bag fabric. Knockdown, mortality and number of progeny were recorded for different exposure periods (24, 48 or 72 h) and oviposition periods (7, 14 or 21 d). Additionally, mini bags were made from ZeroFly bags, PP bags, laminated PP bags and jute bags, and used to determine ability of adult S. oryzae, T. castaneum and Rhyzopertha dominica (F.) to chew through the bags and efficacy of ZeroFly bags at preventing insect infestations from outside and to contain infestations within bags. Knockdown assessment for ZeroFly bag fabric showed that time required to knockdown 99% of S. oryzae and T. castaneum was <3 h. For 72-h exposure to ZeroFly bag fabric, mortalities for S. oryzae and T. castaneum were 76.7 and 62.2%, respectively; mortality was ≤6% in other fabrics. ZeroFly bag fabric also significantly suppressed progeny production by S. oryzae and T. castaneum for all exposure periods. No insects from the three species tested were able to chew through miniature ZeroFly bags, indicating the bag fabric will prevent entry or exit of insects.  相似文献   

2.
The deltamethrin incorporated polypropylene (PP) bag, ZeroFly® Storage Bag, is a new technology to reduce postharvest losses caused by stored-product insect pests. Maize was pre-fumigated and used for the following treatments: ZeroFly bags filled with untreated maize, PP bags filled with maize treated with Betallic Super (80 g pirimiphos-methyl and 15 g permethrin per liter as an emulsifiable concentrate (EC)), and PP bags filled with untreated maize (control). The experiment was conducted from February–August 2015, at four sites in different locations of the Middle Belt of Ghana. Moisture content (MC), number of live and dead insects, insect damaged kernels (IDK) and maize weight loss data were collected monthly. ZeroFly bags and Betallic treatment significantly reduced insect damage compared to the control treatment. ZeroFly bags were able to keep IDK levels below 5% for 4 months, but the levels increased to 5.2 and 10.2% by 5 and 6 months of storage, respectively. In the control, IDK increased significantly over time and reached 32% after 6 months. The ZeroFly bag was effective against Sitophilus, Tribolium and Cryptolestes species for 4 months. Mean weight loss of ≤3.68% was recorded in ZeroFly bags during 6 months of storage whereas 11.88% weight loss occurred in the PP bags by 6 months of storage. Based on our results, ZeroFly bags were found to have potential for use in the reduction of postharvest grain losses in bagged grains. Maize may still have been infested during bagging hence ZeroFly bags were effective for storage for only 4 months. However, greater benefits of using ZeroFly bags are realized if insect-free grains or legumes are stored in bags.  相似文献   

3.
4.
SEM and UV-microscopic investigation of glue lines in Parallam® PSL   总被引:1,自引:0,他引:1  
? PSL were investigated using scanning electron- and UV-microscopy. In the SEM it was found that resin penetrates predominantly through cut open tracheids and rays. Bordered pits block the flow of resin from cell to cell whereas simple pits are only a minor obstacle. UV-absorbance spectra of cells from the glue line area indicated the presence of phenol-formaldehyde resin in the wood cell wall. Compared to the pattern of absorbance of pure cell wall substance, spectra of cells embedded in the glue showed significant differences which were attributed to the penetration of phenol-formaldehyde resin during the process of gluing.
? PSL wurden mit dem Rasterelektronenmikroskop und dem UV-Mikroskop untersucht. Im REM zeigte sich, da? Leim vor allem in angeschnittene Tracheiden und in Holzstrahlen eindringt. Ein Flie?en durch Hoftüpfel konnte nicht nachgewiesen werden, wohingegen einfache Tüpfel ein geringeres Hindernis darstellen. UV-Absorptionsspektren von Holzzellen aus dem Leimfugenbereich deuteten auf das Vorhandensein von Phenol-Formaldehydharz in der Zellwand hin. Die Spektren dieser Zellen wiesen im Vergleich zum Absorptionsverhalten der reinen Zellwandsubstanz deutliche Unterschiede auf, die auf das Eindringen von Phenol-Formaldehydharz w?hrend des Verleimvorganges schlie?en lie?en.
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5.
In the present study, Carifend® an alpha-cypermethrin-coated net, was evaluated for the control of Lasioderma serricorne and Ephestia elutella in semi-field and field tests in two storage facilities. In the semi-field tests, three Carifend® Multi-Cubicles (CMCs), within which one carton box filled with tobacco was placed, were suspended in three separate rooms. Two MoBe traps were placed, one inside and one outside of each CMC. Three additional tobacco quantities in similar carton boxes, with a MoBe trap on them, were placed in three separate adjacent rooms and served as controls. In each room, 50 L. serricorne and 50 E. elutella adults were released outside of each tobacco quantity and the traps were inspected at weekly intervals for 3 weeks. A similar approach was followed in the field test conducted in a commercial tobacco storage facility. However, no insects were released and the test was based on the naturally-occurring immigrations of populations of E. elutella and L. serricorne from outside the facility or from unprotected tobacco. In semi-field tests, significantly more adults were captured in the first week in the control traps compared to counts from CMCs, either inside or outside. However, differences were significant only in the case of E. elutella. Only one single L. serricorne individual was found in the traps that had been placed inside CMCs, whereas no adult E. elutella were detected inside CMCs. In the field-test, traps that had been placed inside the CMCs captured only 3 and 1 adults of E. elutella and L. serricorne, respectively, during the entire survey period. Results of this study show that Carifend® is highly effective for the control of both species on stored tobacco, and could be further successfully utilized as an alternative method over the use of traditional insecticidal treatments (such as repeated fumigations of phosphine gas) on tobacco.  相似文献   

6.
For purposes of wood preservation, stabilization and fire protection, the penetration ability of bio-inspired environmentally friendly Sebosil® nanosols in axial direction of the pine tracheids were investigated using macroscopic evaluations and EDX microanalysis.  相似文献   

7.
α-Lactalbumin (α-La) and lysozyme (LZM) each contain four disulfide bonds but no free SH group, whereas myoglobin (Mb) possesses no disulfide bond or free SH group. In this work, the pressure-induced gelation of α-La, LZM and Mb in the absence and in the presence of β-lactoglobulin (β-Lg) was studied. Solutions of α-La, LZM and Mb (1–24%, w/v) did not form a gel when subjected to a pressure of 800 MPa and circular dichroism analysis revealed that both α-La and LZM are pressure-resistant proteins. In the presence of β-Lg (5%, w/v), however, a pressure-induced gel formed for α-La and LZM (each 15%, w/v) but not for Mb (15%, w/v). One- and two-dimensional SDS-PAGE demonstrated the disulfide cross-linking of proteins was responsible for the gelation. Although α-La and LZM are homologous and have the same disulfide bond arrangement, the texture and appearance of the gels formed from α-La/β-Lg and LZM/β-Lg were markedly different even when induced under the same experimental conditions. Microscopic analysis indicated that phase separation occurs during the gelation of LZM/β-Lg but not during the gelation of α-La/β-Lg. NMR relaxation measurement revealed that the association of water molecules with the protein matrix in the α-La/β-Lg gel is tighter compared to that in the LZM/β-Lg gel. These results indicate that the gel-forming ability of a globular protein under high pressure is related to the primary structure of the protein, and that the gel properties depend on the cross-linking reaction and on the phase behavior of protein dispersion under high pressure.  相似文献   

8.
This study aimed to (1) quantify carotenoids in leafy vegetables and plants of nutritional and medicinal importance, (2) evaluate retinol equivalent (RE) of provitamin-A carotenoids and (3) determine efficacy of β-carotene from Chenopodium album and to compare with retinol formed on feeding to retinol-deficient rats for 3 weeks. β-Carotene and lutein contents (mg/100 g dry weight) ranged from 1.5 to 120 and 11.7 to 185 (leafy greens) and 0.4 to 34.7 and 11.8 to 679 (medicinal plants) whereas, α-carotene ranged from 0.3 to 35.6 (leafy greens) and 0.1 to 15.7 (medicinal plants). RE values (mg%) ranged from 0.4 to 20 and 0.42 to 5.8 in leafy greens and medicinal plants. Efficacy of β-carotene (2400 μg/kg diet) from C. album in retinol-deficient rats revealed a 93.6% rise in plasma retinol levels from 0.53 to 8.4 μM. The plants analysed are a good source of retinol precursors and biologically active lutein; therefore can be exploited to meet carotenoid requirements.  相似文献   

9.
The addition of orange-fleshed sweet potato (OFSP) to the food environment is an effective nutrition-sensitive agricultural approach to improve vitamin A intakes. However, the adoption of this biofortified crop merits further study. The objective of our research was to understand factors that affect Mozambican farmers’ adoption and retention of OFSP varieties, with a specific interest in the retention of planting material. Field research was conducted in three provinces of Mozambique during 2015. Provinces with different OFSP intervention histories were selected to allow for the identification of site-specific factors and the impact of variable approaches over time. Qualitative inquiry was used to assess participants’ progress through the five stages of the Innovation-Decision process in the Diffusion of Innovations Theory. Ninety-five producers, consumers, and market stakeholders of OFSP participated in semi-structured in-depth interviews and focus groups. Results indicate that diverse factors influenced the adoption and retention of OFSP, including organoleptic qualities, taste preferences, access to planting material, agronomic traits, environmental conditions, lack of capital for inputs and labor, unstable markets, and limited sharing of information and planting material across farmer networks. Current OFSP varieties were acceptable to Mozambican farmers and consumers, but there are several remaining challenges to reaching a critical mass such as lack of access to planting material, perceptions of superior drought tolerance of white-fleshed sweet potato (WFSP), and the belief that OFSP requires additional effort to cultivate (e.g. weed removal, measuring space between plants). Key recommendations which may be considered in future planning for OFSP interventions in Mozambique and other countries include enabling decentralized vine multipliers to provide vines to community members at no cost, continued focus on breeding and distribution of more drought tolerant varieties of OFSP, and training on the similarities in agronomic practices required for producing and preserving OFSP and WFSP.  相似文献   

10.
Aflatoxins are important mycotoxins that represent a serious risk for human and animal health. These mycotoxins are mainly produced by Aspergillus flavus and Aspergillus parasiticus, two closely related species with different array of aflatoxins. In this work, two specific quantitative PCR (qPCR) assays were developed to detect and quantify both species in wheat flour using primers based on the multicopy ITS2 rDNA target sequence. The species specificity of the assays was tested in a wide range of strains of these species and others colonizing the same commodities. The sensitivity of the assay was estimated in 2.5 pg/reaction in both species. Discrimination capacity for detection and relative quantification of A. flavus and A. parasiticus DNA were analyzed using samples with DNA mixtures containing also other fungal species at different ratios. Both qPCR assays could detect spore concentrations equal or higher than 106 spores/g in flour samples without prior incubation. These assays are valuable tools to improve diagnosis at an early stage and in all critical control points of food chain integrated in HACCP strategies.  相似文献   

11.
Further development of theory and instruments to support measurement of emotional responses to consumer products has been called for. This research contributes by exploring how psychological traits linked to individual differences in perception of emotion affect responses on the 39-item EsSense Profile® (rating version). Two trait inventories were studied – emotional intensity (EIS-R) and private body consciousness (PBC). Results from four consumer studies (n~1500) suggested that the impact on EsSense Profile® responses was bigger when data were collected online and in response to food words than in laboratory (CLT) settings when actual foods were tasted. For example, in online responses to a product concept describing a snack bar with appetite control benefits, people with higher scores on the positive sub-scale on the EIS-R inventory scored positive EsSense Profile® words higher than those with lower scores on this sub-scale. A similar result was found for private body consciousness. In a second online study, those people with higher PBC scores rated the emotional words higher than those people with lower PBC scores. Conversely, in laboratory CLT settings, two studies found fewer effects linked to these traits on EsSense Profile® responses elicited as participants consumed chocolate and apples. Numerous gender effects on EsSense Profile® responses were established, and it is suggested that aspects of participants’ emotional psychologies be measured if researchers are interested in how emotional responses to consumer products differ between men and women. In some instances, participants’ product use frequency and trait food neophobia scores were found to affect EsSense Profile® responses. Replication with other surveys eliciting food-related emotional responses is recommended.  相似文献   

12.
Although high concentrations of zinc and manganese were found in mandibles of insect larvae that bore into seeds, these metals were not detected in mandibles of insect larvae that attack previously damaged seeds. Metals were present in the larval mandibles of a lepidopteran, the Angoumois grain moth (Sitotroga cerealella), and eight coleopterans, the lesser grain borer (Rhyzopertha dominica), cigarette beetle (Lasioderma serricorne), drugstore beetle (Stegobium paniceum), spider beetle (Gibbium aequinoctiale), warehouse beetle (Trogoderma variabile), cadelle (Tenebroides mauritanicus), larger black flour beetle (Cynaeus angustus), and cowpea weevil (Callosobruchus maculatus). Larvae of these species can chew into seeds. Larvae of six other coleopterans, the varied carpet beetle (Anthrenus verbasci), sawtoothed grain beetle (Oryzaephilus surinamensis), rusty grain beetle (Cryptolestes ferrugineus), red flour beetle (Tribolium castaneum), longheaded flour beetle (Latheticus oryzae), and granary weevil (Sitophilus granarius) have little if any ability to chew into seeds, and did not have metal in their mandibles. Larvae of the granary weevil hatch and feed within seeds that were penetrated previously during egg deposition by adults. However, newly hatched larvae of the cowpea weevil and the Angoumois grain moth have to bore through the seed coat before they begin feeding, and they have mandibles with high concentrations of zinc. These data support the hypothesis that deposition of zinc and/or manganese in larval mandibles enhances the larva's ability to penetrate seeds.  相似文献   

13.
Texture properties are very important quality parameters of Appenzeller® cheese. The Appenzeller® Cheese Makers Association defines optimal texture quality as being characterised by a softness that lasts at least three months. During winter production, texture-related problems are sporadically encountered. In the present study, ten Appenzeller® cheese loaves with optimal texture properties aged for 90 days and ten loaves with dry and firm texture of the same age were selected and characterised through a uniaxial compression test and with physicochemical and biochemical methods. All cheeses had been produced in the same week during winter (January) in different cheese factories and ripened for three months. The aim of the study was to determine the main factors responsible for classification into the two groups based on univariate and multivariate statistical analysis tools. The three main parameters influencing the force at 33% deformation in this study were calcium, water, and free amino acids.  相似文献   

14.
Delvotest® T was evaluated for its capability at detecting residues of 27 antibiotics in raw cow’s milk and in some dairy ingredients (skimmed and full-cream milk powders). The kit was used as a screening tool for the qualitative determination of antibiotics from different families in a single test. Results delivered by such a method are expressed as ‘positive’ or ‘negative’, referring to the claimed screening target concentration (STC). Validation was conducted according to the European Community Reference Laboratories’ (CRLs) residues guidelines of 20 January 2010 and performed by two laboratories, one located in Europe and the other in Asia. Five criteria were evaluated including detection capability at STC, false-positive (FP) rate, false-negative (FN) rate, robustness and cross-reactivity using visual reading and Delvoscan®. STCs were set at or below the corresponding maximum residue limit (MRL), as fixed by European Regulation EC No. 37/2010. Four antibiotics (nafcillin, oxytetracycline, tetracycline and rifaximin) out of 27 had a false-negative rate ranging from 1.7% to 4.9%; however, it was still compliant with the CRLs’ requirements. Globally, Delvotest T can be recommended for the analysis of the surveyed antibiotics in raw cow’s milk, skimmed and full-cream milk powders. Additional compounds were tested such as sulfamethazine, spiramycin and erythromycin; however, detection at the corresponding MRL was not achievable and these compounds were removed from the validation. Other drugs from the sulfonamide, aminoglycoside or macrolide families not detected by the test at the MRL were not evaluated in this study. Regarding the reliability of this rapid test to milk-based preparations, additional experiments should be performed on a larger range of compounds and samples to validate the Delvotest T in such matrices.  相似文献   

15.

Purpose

To assess the repeatability and reproducibility of Visante? OCT and Oculus Pentacam HR® in measuring central (CCT) and topographic corneal thickness (TCT) along the principle meridians in keratoconus (KC) corneae.

Method

Twenty participants diagnosed with KC were recruited. There were two study visits. On the first study visit, two repeated corneal thickness measurements were obtained with each instrument. Measurements were repeated at least 48hrs later in the same order. TCT were recorded in the 90, 180, 45 and 135 meridians at 1mm intervals across 8mm chord.

Results

Mean CCT for Visante? OCT was 484.97 ± 43.14 μm (range: 484.84–486.09) and Oculus Pentacam HR® was 478.86 ± 45.31 μm (range: 477.20–480.53). No significant difference in TCT between the two visits (p = 0.54) and measurements (p = 0.63) for Visante? OCT. For Oculus Pentacam HR®, no significant difference was found for each visit (p = 0.18) but differences existed in the measurements outside of the central region (p = 0.001). Tukey post-hoc analysis shows the differences (p ? 0.05) were found in the +1 and +4 (supero-temporal) locations in the 135 meridian. Significant differences were found comparing the two instruments, (p < 0.05). Bland Altman plots were used to demonstrate the differences between the two instruments and indicate their limits of agreement.

Conclusion

Both instruments gave repeatable measurements as no significant differences were found in most locations in all meridians. Comparing the two instruments, they were not reproducible in all locations.  相似文献   

16.
The electrical resistance of jute needle-punched non-woven fabric has been studied. Statistical model using central composite rotatable experimental design is developed for electrical resistance depending on the three important parameters of needled non-woven fabric, i.e. punch density, depth of needle penetration and mass per unit area. From this model and its contour diagrams, the effects of different parameters can be understood on electrical resistance of those fabrics. Prediction of electrical resistance can be made knowing the values of independent parameters. The correlation coefficients between observed and predicted values are found to be significant in all the cases. As depth of needle penetration increases for a particular punch density, electrical resistance increases and after reaching to maximum, it decreases having optimum at about 140 punches/cm2 and 12?mm depth of needle penetration. With the increase of area density, resistance decreases. As punch density increases for a particular area density, resistance increases for high needle penetration.  相似文献   

17.
The effects of the weight fraction (concentration) and silica particle size on steady and dynamic rheological responses of shear thickening fluids (STFs) and the quasi-static (QS) penetration resistance of Twaron®/STF composites have been investigated. The STFs have been made by mechanically dispersing 12 or 60 nm silica particles in polyethylene glycol with molecular weight of 400 gr/mol at three different concentrations. Rheological results indicate that with the increase in the concentration of silica in the STF, the critical shear rate (onset of shear thickening) diminish, the initial, critical, and ultimate viscosities increase and the slope of the shear thinning and shear thickening regions tend to be more steeper. Regarding STFs with larger particle sizes, critical shear rate, the initial, critical, and ultimate viscosities as well as the viscoelastic modules diminish. Addressing the Twaron®/STF composite, the increase in STF concentration and reduction in the silica particles size contribute to considerable increase in the puncture characteristics. The most noticeable puncture characteristics turn out in the case of 35 wt. % STF/Twaron® composites containing 12 nm particles in which the maximum bearable load and the maximum absorption energy are nearly 3.6 and 2.3 times larger than those of the neat Twaron®.  相似文献   

18.
19.
Elastic recovery is one of the most important mechanical properties especially of clothing applications. This property is more and more significant when the textile structure contains elastane filament and has significant elasticity. In this study, we investigate the effect of the Dorlastan® draft and yarn count on the elastic recovery of cotton-covered Dorlastan® core spun yarns. These yarns are used as weft yarns in denim fabrics. Dorlastan® core spun yarns with different counts 100, 50, and 25 tex, with different elastane drawings and with the same twist factor are used. Our test results revealed that the Dorlastan® ratio and yarn count are important factors in influencing the elastic recovery.  相似文献   

20.
The Explorer® 2.0 tube test is a microbial inhibition test for the screening of antimicrobial residues in food samples. The new e-Reader® device coupled to Explorer® 2.0 operates by incubation at a selected temperature, determination of the endpoint of the assay and interpretation to generate results. This system was validated for muscle samples according to the European Commission Decision 2002/657/EC. Sensitivity towards 25 substances from several groups of antimicrobials was investigated in a first step. Detection capabilities for six substances representing the six major antimicrobial groups were also determined in bovine muscle. The detection capabilities for amoxicillin (10 µg l?1), cefalexin (200 µg l?1), doxycyclin (100 µg l?1), sulfamethazine (100 µg l?1), tylosin (100 µg l?1) and neomycin (200 µg l?1) were in all cases at or below the maximum residue limit (MRL). Specificity and applicability of the test were demonstrated with muscle samples from four animal species (bovine, porcine, ovine and poultry) and results were found to be satisfactory. Ruggedness was evaluated on negative and spiked samples with sulfamethazine as a representative antimicrobial. Neither false-positives nor false-negatives were detected when varying the sample volume, the time of pre-incubation, the temperature of incubation and the batch of the test. These results prove that Explorer® 2.0 coupled to e-Reader® is a valuable tool for the screening of a broad range of antimicrobials in muscle. This new methodology simplifies the analysis and increases the accuracy of interpretation of the test results since the endpoint of the assay is automatically determined and results are interpreted objectively.  相似文献   

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