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In this article, we try to better understand the relationship between learning and crisis through the analysis of recurrent crises. Our study focused on two successive and similar crises experienced by the same organization, namely two hostile takeover bids a French bank (Société Générale) had to cope with in 1988 and 1999. From a literature review within the fields of organizational learning and management crisis, we proposed an analytical grid making it possible to get a better understanding of crisis‐induced lesson‐drawing processes. We then used that grid to analyse and compare the learning processes implemented during the two crises under study. This comparison leads us to suggest that lack of organizational learning is one factor that accounts for crisis recurrence. Conversely, proactive crisis management behaviour – resulting from double‐loop learning – seems to be the most fruitful behaviour to adopt in order to prevent a recurrent crisis and produce long‐term effects in the organization.  相似文献   
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Levels of eight dietary elements were assessed by ICP-AES in virgin edible and beauty argan oil samples prepared from four remote locations of the argan forest, and over a three-year period. The data showed sufficiently little variability to assess that all argan oil samples present, in terms of dietary elements, a similar composition, independently from the tree location within the argan forest. Therefore, adulteration detection by trace element analysis in edible and beauty argan oil is a method that can be generalised.  相似文献   
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Current subsidies to residential water users in Oman are estimated at USD 314 million/y. This study estimates the demand function for residential water in Muscat, Oman, for households living in villas. A two-stage least squares econometric model with lagged average water price was used with socio-economic variables. Price elasticity for residential water in Muscat was estimated as –2.10. This high price elasticity is explained by the large proportion of water used for outdoor purposes. This study indicates that it may be possible to manage water demand in Muscat through modifying the price of water and reforming subsidies for residential water.  相似文献   
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Mycotoxins are secondary metabolites produced by filamentous fungi detected in food, such are grapes. OTA was evaluated in ten handle musts from different Tunisian vineyard. This mycotoxin was found at levels 1.1 mug/L to 4.3 mug/L. A survey was conducted to assess the contamination of the Tunisian vineyard with pathogenic fungal species, in particular those responsible of the OTA production. The results were evaluated for the first time in parcels cultivated in the North, in the Centre and in the South of the country. Italia Muscate and Superior Seedless varieties were concerned at three developmental stages of the berry, setting, veraison and maturity. Carigon variety was used as positive control for musts contaminating by OTA. The main fungal species isolated were Aspergillus spp. (33.32%), Botrytis cinerea (23.32%), Alternaria spp. (12.80%), Cladosporium spp. (10.59%) and Penicillium spp. (8.3%). The isolates of the Aspergillus genus were identified as Aspergillus niger aggregate (77%), Aspergillus carbonarius (15%) and Aspergillus flavus (8%). Their presence was characterized by a significant decrease in the Centre during the veraison and a slight increase in the North and the South during the maturity stage. Furthermore, when comparing Superior Seedless and Italia Muscate cultivated in the same area, the aspergilli were particularly less abundant at the setting stage in the case of Superior Seedless. There is no correlation between the OTA amount in musts and the contamination by Aspergillus species in different vineyards and for grape varieties studied.  相似文献   
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Color Doppler ultrasound (CDUS) seems to be an effective imaging technique for the diagnosis of renal vascular diseases. It is already the modality of choice for the detection of acute renal vein thrombosis and nonocclusive intrarenal vascular disorders including iatrogenic arteriovenous fistula and false aneurysm, particularly in patients with impaired renal function that precludes the use of iodinated contrast agents. Although proximal Doppler interrogation remains an important step in diagnosing renal artery (RA) stenosis, useful hemodynamic information can be obtained from the distal arterial bed. When CDUS fails in identifying proximal RAs, normal waveform velocity and morphology obtained from intrarenal arteries enable one to rule out RA occlusion and most of the severe stenoses (> or = 80%). Such information, which is not subject to a significant risk of technical failure, seems to be particularly useful in studying patients with acute renal failure of suspected vascular origin. Despite the extreme variability in reported performance between studies, CDUS has seemed to be a valuable tool compared with other noninvasive modalities in the diagnosis of RA stenosis. Whereas a CDUS-based strategy is already accepted in numerous specialized centers, a thorough evaluation of diagnostic criteria and extensive training of operators will allow CDUS to be widely accepted for the screening of patients at high risk for renovascular hypertension.  相似文献   
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The waste of inedible parts of pineapple, particularly in tropical countries, contributes to environmental burden. This study aimed to utilize pineapple stem waste as a source of starch-based pharmaceutical excipient. The starch was isolated from pineapple stem waste using a simple process without applying harsh chemicals. The isolated starch (PSS) was then physically modified through gelatinization and spray drying to improve its physical properties. Starch characteristics were identified by FTIR, TGA, and XRD analysis. The SEM imaging showed morphological change with reduced surface roughness due to physical modification of the starch. Decreased crystallinity of modified starch (MPS) was confirmed by our XRD results: the peaks of A-type crystalline at 2θ of 13°, 15°, 18°, and 23° were present in PSS, yet mostly absent in MPS. Thermogravimetric analysis showed that MPS behaved differently from PSS and the degradation events occurred at lower temperature. When the starch was spray-dried without prior gelatinization process, the physicochemical characteristics of spray-dried starch resembled untreated starch. Moisture content in PSS (10.66%) decreased after gelatinization to 7.3%. Potential use of MPS was demonstrated by its powder flowability (Student’s t test, p?<?0.05), swelling capacity (Student’s t test, p?<?0.05), and compaction profile. In summary, our findings demonstrated that modified pineapple starch showed better physical characteristics and quite promising as a tablet binder and disintegrant.  相似文献   
9.
The efficiency of a synthesized interfacial modifier agent, acrylic acid grafted polypropylene (AAgPP) in glass fibre reinforced nylon 6/polypropylene (GFRN6/PP) blends has been studied. Scanning electron microscopy clearly shows that the dispersed phase particle size decreases when AAgPP content increases (12‐fold decrease in diameter) resulting in a more stable morphology. The established emulsification curve for this system emphasizes the efficiency of the synthesised AAgPP as a potential interfacial modifier for GFRN6/PP blends. AAgPP at 7.5 wt% is to be considered as the critical concentration for our blend; such a concentration corresponds to maximum interaction between the matrix and the dispersed phase. Strong interactions between the blend components have been observed. The effect of increasing the compatibility agent content on Izod impact, tensile strength, tensile modulus and elongation at yield has also been investigated, and a bell‐shaped trend observed with a maximum at 7.5 wt% AAgPP content. A 25 % increase in impact strength for the unnotched specimen, a twofold increase in tensile strength and a fourfold increase in tensile modulus are obtained. At 7.5 wt% AAgPP, a tough–brittle fracture transition is observed with a 2.5 µm particle size diameter. © 2000 Society of Chemical Industry.  相似文献   
10.
The protein solubility of some citrus seeds flours as well as physico-chemical characteristics were determined by gel filtration, polyacrylamide gel electrophoresis (PAGE), polyacrylamide gel electrophoresis in the presence of sodium dodecylsulphate (SDS-PAGE), and UV-spectrum. The highest solubility was in 0.1 M NaOH followed by both 0.1 M KCl and NaCl, respectively. The lowest solubility was in water. The protein solubility showed a minium with shift towards the acidic side in presence of 0.1 M and 0.5 M NaCl. The PAGE pattern showed two major protein fractions for citron, orange and mandarin seeds. SDS-PAGE proved presence of 3 major polypeptide chains in all seeds proteins. The apparent molecular weight was 37 304, 23 516 and 16 740 daltons, respectively. Also, the major protein fraction in all samples was globulin. The polypeptide chains were 4 for both albumins and globulins, 3 and 2 for prolamins and glutelins, respectively. Gel filtration revealed four peaks in all samples. The major peaks were eluted at 79 and 160 ml. All peaks were principally free from nucleic acids except peak No. 4.  相似文献   
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