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81.
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The increasing number of women in the work force has forced some companies to take a critical look at their maternity policies. Direct costs for these policies are hard to measure. But, demographic, social and legislative pressures may force companies that haven't addressed this issue to do so in the '90s.  相似文献   
83.
Pacific Presbyterian Medical Center has chalked up an impressive string of successes. What's ahead? A $20 million cancer center.  相似文献   
84.
The aim of the paper is to investigate certain aspects of the post‐adoption behaviour of dryland cotton farmers in the Ubombo and Hlabisa magisterial districts of KwaZulu. Particular attention is paid to the socio‐economic determinants of the success (returns per hectare) of the household cotton enterprise.

Multi‐stage sampling methods were used to draw a random sample of fifty cotton‐farming households from each of the two study districts. The data were collected by interview survey and analysed using principal components and regression techniques.

Results suggest that the success of the household enterprise in both areas is largely determined by the socio‐economic environment under which the producer operates. The most important success‐determining factors are those relating to the human capital endowments and economic status of the household.  相似文献   

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Listen and learn     
After making a solicitation, a lot can be gained by listening to a donor's questions. Do not simply answer the question. Consider why they asked it in the first place.  相似文献   
88.
This paper presents the results of the concentrations (μg/L) and fluxes (g/ha) of priority substances in stormwater from three watersheds with different land use patterns (namely, residential, urban dense, high urban density). Samples were collected at the outlet of these watersheds. Thirteen chemical groups were investigated corresponding to 88 individual substances before treatment. Results showed that stormwater discharges contained 55 substances, among them some metals, organotins, PAHs, PCBs, alkylphenols, pesticides, phthalates, cholorophenols and volatile organic compounds. Therefore, stormwater was highly contaminated. However, this contamination was often comparable from site to site, since no significant difference of the pollutant load was observed between the land use patterns.  相似文献   
89.
The aim of this work was to study the accumulation and fractionation of P in the inlet and outlet sediment of a constructed wetland for the wastewater treatment of a metallurgic plant in Argentina. It was important to predict whether P could be released into the water again by changing environmental conditions or retained over time. P-fractionation was performed using a sequential extraction method. Sediment cores were sliced at depths of: 0-3; 3-7 and 7-10 cm. Sediment showed high pH values and anoxic conditions. In the inlet area, P was principally bound to the carbonate fraction, whereas in the outlet area, it was mainly bound in the residual fraction. This behavior was justified by the effluent composition, which is rich in Ca2+ and Fe3+ and presents high values of pH and conductivity. These conditions favor CaCO3 and Fe(OOH)n precipitation and the subsequent sorption of P to their surface. The sediment active layer involved in the exchange reactions was the superficial one (0-3 cm). The wetland is highly efficient in P retention. P was retained by sediment in fractions that will not release it to the water while chemical and environmental conditions of the system are maintained.  相似文献   
90.
This study aimed at enhancing knowledge on the fate of diclofenac (DF), together with its main human metabolite 4'-hydroxydiclofenac (4'OHDF), during wastewater treatment by using a laboratory-scale membrane bioreactor (MBR). The reactor was fed continuously with non-radiolabelled diclofenac for a one month period prior to a single pulse of a 14C-radiolabelled solution of DF and 4'OHDF. The solution spike contained approximately 25% 4'OHDF and 65% DF, which corresponds to the ratio observed in municipal sewage, as well as traces of two other metabolites. The radioactivity was monitored for a total of twelve days in the various output streams. The calculation of the complete mass balance in the system demonstrated that the major part of the radioactivity left the reactor with the permeate (88.7%), while 2.1% was recovered in the excess sludge. Negligible amounts were recovered in the off-gas traps and on the membranes. Chromatographic analyses of effluent samples, by means of HPLC-MS coupled in parallel to a radiodetector, displayed a different pattern than the one of the spiked solution. It showed the occurrence of three additional metabolites.  相似文献   
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